ASK 21 Instructions For Continued Airworthness

User Manual: ASK-21 Instructions for Continued Airworthness

Open the PDF directly: View PDF .
Page Count: 87

nsH 2t

Flight Manual

lnstructions For Continued

Airworth iness

Repair Manual

ALEXANDER SCHLEICHER SEGELF'LUGZEUGBAU

D-36163 Poppenhausen (L.lasserkuppe) Germany

--- Phone 06658 - 890

AIRWORTHINESS

SCHLEICHER ASK2I

fhis Manual is FAA approved for U.S. registered

gliders and is required by FAA Type Certiflcate

Data Sheet No. c 4? EU 1.10,83

Resistrationt I. A.Z.I.G. B

Factory Serial Number: 2.1..9. .3. .7 .

Owner:

l-. German edltion of Instructions for Continued Air-

,,/orthlness are-approved under S12(1)2 Luft Gerpo

Publ ished: l{arch 9, 1.983

Approval of translation has been done by best know-

ledge and Judgement. In any case the original text

ln Gerhan language ls authoritative.

ASK 21 Maintenance Manual (us-version)

Record of Revisions

lssue: March 9, 1983

Revision:

Rev

No.

Page (s)

Affected Date of

Revision Date of

lnsertion Ref. /

Signature

45 20.12.83 03.01.84 Juw

11 09.03.84 18.03.84 Juw

2.49 16.05.84 08.06.84 Juw

'15

2, 58, 59 08.06.84 23.06.84 Juw

2,3, 43, 45, 45a,45b, 60 03.11.87 23.11.87 Juw

24 04.05.92 19.10.92 Juw

corre

ction

2,41 26.04.99 Juw

45d, 45e, 45f 25.07.O3 19.09.03 mm

Ml (alternative rim for main

wheel) 01.06.10 23.08.10 mg

Pase 1

Instructlons For Contlnucd Alnrorthlness SCHLEICHER ASK 21 5

Lower chord = ar17 m = 3rB4 ft

Airfoi1 Wortmann FX 71-L-L50,/30.

Rudder

33 % of vertical tail unit chord

)

Alcd = 0,45 m- - 4186 sqft

Chord (middle) = 0,33 m = 1'08 ft

Horizontal tail unit

Span

Area

Aspect ratio

Area

Span

Heigh t

= 3,1 m = 10116 ft

= a,92 m2 - 2o,64 sqft

= 5'05

= 0,35 m- - 3177 sqft

= 1,35 m = 4.43 tl

= 0113 m = 0,43 ft

Elevator

Area = 0,576m2 = 6t 19 sqft

30r1 % of horizontal tail unit chord

Airbra\es

Schempp-Hirth type, on upper wing on1y.

W eiqhts

Max all up weight = 600 daN = 1320 1bs

Empty weight, app. = 370 daN = 814 lbs

Weight of non lift

producing parts = 410 daN = 902 lbs

Max wj-ng loading = 33t4 daNm2 = 6184 lbssqft

Max load of occupants, luggage, etc. :

see load table in the Flight Manual.

March 9, 1983

Instructlons For Contlnucd Alraorthlncss SCHLEICHER ASK 21 6

II. DESCRIPTION OF AIRCRAFT AND COMPONENTS

Ai rcra ft

The A,SK 21 is a two-seater midwing with T-tail, airbrakes,

fi-xed shock absorbing main wheel and a nose whee1.

The structure is made in a highly developped fiberglass

technology. On certain crilical areas carbon fibers are

us ed.

Winq

Double T spar made of fiberglass roving flanges and fi-

berglass cloth webs. The skin consists of a 9mm Conticell

core with fiberglass on both sides.

Easy wing assembly by longue and fork connection, fixed

by two 356 bo1ts. Two shear bolts at the fuselage which

fi-t the bushings in the wing center rib, absorb the shear

loads to the fuselage. The rear shear bolts are secured

by an automatic safety device.

Fuse I aqe

The fuselage is designed as a honeycomb (tubus core) con-

struction throughout which means considerable increase of

strength compared to non sandwich she1Is.

2-piece canopy, forward hinged in front and rearward hinged

in back; adjustable back rests.

Tai I pL ane

T-tail consisting of the same construction as the wing.

Control Surfaces

Sandwich construction wi-th Rohacell foam core.

IfI. DESCR]P?ION OF A/C ASSEMBLY & EQUIPMENT

III.1 CONTROL SYSTEMS

Genera_L

Except for the rudder which is operated by cables r

March 9, 1983

InEtructlns For [ontinud Airyorthinrrs Schhicher ASK 21

(l,

vtc

t, :;

idg

-E ..-

tg-

L:= o,

gtsE

#+ E

oz<t=

E-

lrl ,<

Ifi

Controt Systems \l//

'\ \\r',

\I&\

\" -\t-\

\\\\j\

lij r--r 1 {'}!:-l

lnstructions For Gontinued Airworthiness SCHLEICHER ASK 21

1.2 PAGES INCLUDED

Cover page March 9, 1983

1 March 9, 1983

2 July 8,2003

3 May 4,1992

4 March 9, 1983

5 March 9, 1983

6 March 9, 1983

7 March 9, 1983

8 Dec. 20,1983

I Dec. 20,1983

10 March 9,1983

11 Dec. 20,1983

12 March 9, 1983

13 March 9, 1983

14 March 9, 1983

15 March 9, 1983

16 March 9, 1983

17 March 9, 1983

18 March 9, 1983

19 March 9,1983

20 March g, 1983

21 Marcfi 9, 1983

22 March 9, 1983

23 March 9, 1983

24 March 9, 1983

25 May 4,1992

26 Marcn 9, 1983

27 May 4,1992

28 March 9, 1983

29 March 9, 1983

30 March 9,1983

31 March 9,1983

32 March 9,1983

33 March 9,1983

34 May 4,1992

35 May 4,1932

36 Marct 9, 1983

37 March 9,1983

38 March 9,1983

39 March 9,1983

45a

45b

45c

45e

March 9, 1983

April 26, 1999

March 9, 1983

Oct. 16,1987

March 9, 1983

Oct. 16,1987

May 4,1992

March 9, '1983

March 9, 1983

Dec. 20,1983

March 9, 1983

May 25,1984

July 8, 2003

May 4,1992

March 9, 1983

Correction: 08.07.2003 / Juw

Inslructions For Continued Airworthiness Schteicher ASK 21

the whole control system ls actuated by pushrods. The lons

pushrods are 16 0 x 1,A lll|Il alufllinlulll wlth ball bearlng sup-

ports, The cockplt controls and the shorter oushrods are

welded steel. The control system levers are rllllled duraluml-

nlum or welded steel,

Elevator control system

Both control stlcks are bullt as 2-armed levers and feature

universal Jolnts, The control sttcks are linked together by

a maln steel tube torslon rod at the bottom, Thts torston rod

features at its front and rear end an adJustable stop for

both control stlcks, Another bent steel tube torslon rod leads

from the rear control silck to a combtned elevator/aileron

rocker arm. From there a short alumlnium pushrod leads to a

180" duralumlnium bellcrank whlch ts llnked uo by a lons alu-

lnlnlum pushrod whlch runs throush 4 suoport bearings; the

support bearlngs consist of a flberglass bracket with 3 ball

bearlngs. Vla a 90" duralumlnlum bellcrank, the contr0l for-

ces are lead upwards 1nt0 the fin uslng a ftberglass plastic

pushrod, Here connects a 180' duraluminium bellcrank to a short

alumlnium pushrod which In turn connects to a t412,41IH0TELLIER

jolnt l,,hich ooerates the elevator,

Elevator l.ll th automailc connecilon I

Instead of the alullllniulll pushrod, an actuating pushrod 1s ln-

stalled, rlhlch ts suiported wlth a paraltel rocker,

Tr 1lI}

The trltll ls sprlng susoended and conslsts of 2 trlrrl levers,

I connectlng pushrotl and the 2 trlrll sprlngs with slotted gate

sheet metal, The trlm levers are connected to the control silcks

liith a knurled nut at the control stick bearlng bolt, A frictlon

brake ls tlghtened wtth thls knurled nut at the control silck

December 20, 1 983 TN n0.11

Insfructions For Continued Airyorthiness Schleicher ASK 21

bearing bolt, The braklns force should be dlstributed evenly

between the front and rear brake, The brake should be tighten-

ed so strons that even wlth extremely opposed posltions of

stlck and trim lever, the trltn l{l1l not move, The trim con-

nectlng pushrod features a stop at lts front and rear end.

The sprlngs lllth the adjustlng plate between them, are sus-

oended lnto the 2 rings of the front control shaft. The ad-

Justlng plate ltself 15 mounted to the bolt of the trlrn con-

necting pushrod; here the trim ntay be adjusted.

The trlm should be adjusted such that illth 1 pllot and the trtm

set full forward, a trln,ll1led speed of 150-160 km/h (81*86,3 kts.;

93,2-99,4 mph) is reached; then the trlm lever ls ln a sliSht-

ly forward Dosltlon when the stlck ls free and ln tts center

DoSitlon (elevator connected),

To adjust the trim roughly to a trtmmed speed of max, 160 km/h

(86,3 kts; 99,4 mph)r

1 , Connect elevator,

(Thls 1s inappllcable when your gllder features the auto-

matlc elevator connectlon) .

2. Adjust the trlm spring such that the silck ls set to the

above-mentloned relatlve posltion to the trlril lever. Frlc-

tlon must be balanced by "feellng for" the center posiilon.

Trirll lndlcator

In addltton to the vislble posltlon of the trirn lever itself,

the trirll features a triIIl indtcator, The trlm tndlcatton should

be in the center Dosltlon when the trlm lever ls vertical to

the Sllder's longltudlnal axls. It can be adjusted by openlng

the clamp at the trlm connecting oushrod and by disolacing the

Bowden cable, Then rettghten the clamp.

December 20, 1 983 IN n0.11

Instructlons For Contlnucd Alrsorthlneas SCHLEICHER ASK 21 13

Aileron control svstem

A short aluminum pushrod leads from the horizontal

aileron control system lever at Lhe rear elevator,/

aileron control system torslon rod upwards to a 90o

duraluminum bellcrank in the fuselage. By a HOTELLIER

joint (M12.41) follows from here the long aluminum

pushrod in the wing. This pushrod is supported alto*

gether seven times in each three ball bearings. For

the compensation of the bellcrank travels short steel-

tube pushrods are articulated by balI bearings {14c6}

at both ends of the long pushrod. The inner short

pushrod features the HOTELLfER connection with the ad-

justing screw. At the 90o duraluminum bellcrank the

aileron pushrod acluates the aileron through a HIRSCH-

MANN-UNIBAL adjustable head (SMx CP6).

The stops for the aileron are positioned ln the push-

rod box in front of the rear stick. These are two p1y-

wood blocks glued into the pushrod box and cut out such

that they stop laterally the travel of the front tor-

sion shaft.

March 9, 1983

Instructions For Continued Airyorthiness Schhicher ASK 21 lt.

;

(l,

J"larch 9, 1983

InBtructlons For Contlnucd Alnrorthine8s SCHLEICHER AsK 21 15

R}dder control svstem

The rudder is actuated by cable (3129 LN 9374).

Both fronL and rear pedals are adjustable. The rudder

cables are running from a fixed point through S-type

pedal loops to an adjusling plate in the rear cockpit.

Here are joined togelher the cables from the front

and rear pedals. From the adjusting plate the cables

run through nylon tubes to the rudder-actuating lever.

At the adjusting plate slight inaccuracies in

the cable length may be adjusted and also the pedal in-

clination. The cables are held taut by springs at the

pedals; at the rear pedals this spring serves simul-

taneously for holding down the adjusting stop.

For the adjustment of the cables at the adjustment plate

the rear seat must be removed.

The stop forthe rudder is located in the back of the

rudder.

The rudder lever strikes a stop at the bearing bracket.

llarch 9, 1983

lnstructions For Continued Airworthiness Schleicher ASK 21

1.3 CONTENTS

l. General

1.1 Log of revisions

1.2 Pages included

1.3 Contents

1.4 Technical Data

ll. Description of aircraft and components

lll. Description of a/c assembly and equipment

lll.1 Control systems

lll.2 Landing gear

lll.3 Radio equipment

lll.4 Oxygen equipment

lll.5 Pressure ports & connections for the instruments

lV. Rigging data

V. Airworthiness Limitation Section

Vl. Weights and C.G. positions

Vl.l Weight and balance sheet

Vl.2 C.G. found at the last weight and balance procedure

Vl.3 lnstallation of ballast in the tail

Vl.4 Weights & tailheavy static balance of control surfaces

Vll. Check Lists

Vlll, Periodical inspections

lX. Lubrication Scheme

X. Placards and markings

Xl. Repairs

Xll. Modifications

Xlll. Description of symbolic placards

XlV. Appendix

XlV.1 Equipment List

XlV.2 Maintenance lnstructions

TN24 dated O4.O5.92 (Juw) 3

Insfructions For Continued

elevator connection

Schleicher ASK 21

I elevator

automat ic

TN no.11

up to Seriol no. 21 205

Aileron control

Becember 20, 1963

)

Instructions For Continued Airrorthiness Schteicher ASK Z1 1b

Front Pedqts

l'iarch 9, 1983

Instructions Por Contlnucd Alraorthlna6r SCHLEICHER ASK 21 tt

T.4 TECHNICAL D,{TA

Wing

Airfoil Wortmann FX SO2 196

FX 60 -126

Span b = 17,00

Area F = 1,7,95

Aspect ratio = 1617

Li = 1'50

tt = or5o

Angle of incidence at root

Dihedral (wing center line)

sweep! iner wlng leading edge,

( i-nner wing )

(wingtip )

m = 55,70 ft

*2 = 192,96 sqft

- 4,92 tL

- L167 fL

- . ro

= +4o

s traight.

- 9,18 ft

= L2s03 sqft

= 0,79 ft

n Ea cr

- wrJL tL

= 8'35 m

= 0:71 m

= 1100 m)

= 1"2,33 m-

Iil

Ai 1 erons

Span

Area (both)

Inner chord

Outer chord

bn = 2'80 m

1, L2 mZ

= 4,24 m

= 0116 m

Fusel aqe

Length (rudder included)

Cockpit width (inner)

Cockpit height

Fuse).age wetted area

vertical tail unit

Hei.ght above fuselage

Area

Aspect ratio

Upper chord

= 27 r4O tt

- 2,33 ft

= 3116 lL

= 132,55 sqft

center line

= 1,37 m

,^-_2

= 1'J)/m

= 1,383

= 0,80 m

4149 fL

14,59 sqft

2162 tt

March 9, 1983

Instructions For Continued Airworthiness Schteicher ASK Z1

Trim lever

Stick reqr

(/c

SticNr ossembty ond

Trimlsystem

Morch 9,1983

Instructions For Continued Airyorthiness Schleicher ASK 21 17

March 9, 1983

Instructlons Por Contlnucd Alryorthlncss SCHLEICHER AsK 21 18

Airbrakes

The airbrakes are actuated by pushrods. On the left

cockpit wall runs a connecting rod with a handle each

for the front and rear cockpit. In the front cockpit

the rod is running in a nylon guide, in the rear cock-

pit it is supported by a duraluminum rocker arm. From

this arm another pushrod - placed under the arm - con-

, ^^o

tinues to a 90" duraluminum bellcrank and runs below

the rear spar tunnel wa1l.

The back of the spar tunnel wa11 features two rocker

arms and the pushrod which produces the counterclock-

wise travel of the actuating levers. By a HOTELLIER

joint (M12.41) the pushrods 1n the wing are connected

to the actuating levers. They run through three ball

bearing guides and lead to the ai-rbrake toggle joint

A short pushrod leads to the inner airbrake lever which

on the other hand is connected to the outer airbrake lever

by a pushrod so that synchronous movement is guaranteed.

Stop of the airbrake control: Brake cylinder.

Plarch 9, 19t3

Instructions For Continued Airuorthiness Schteicher ASK 21 19

..It

c7r

tt,

March 9, 1983

Instructions For Continued Airvorthiness Schteicher ASK 21 2A

.tt

-ts1

LJI

-ol

,a EI

// l, I

)$l

Plarch 9, 1983

Instructlons For Contlnucd Alruorthlnaas SCHLEICHER ASK 21 21

I11.2 LAND]NG GEAR

The landing gear consists of the shock absorbing main

wheel 5.00-5 and the non shock absorbing nose wheel

4.00-4. The trailing boom main wheel uses two hollow-

type rubber shock absorbers (type KE 1ZO/95 core A

with mounting member, quality R"K 55).

The rim is a Cleveland wheel 4078 (B), 5.00-5 Type fIIl

Brake: Cleveland brake assy 30-9.

Main brake cylinder: Master cylinder aO-ZO.

Tank for brake fluid: Below rear seat pan on LH sj-de.

Main wheel: Tire with tube 5,00-5,

6p1y rating.

Nose wheel: fire with tube 4.00-4,

4p1y rating.

?ire pressure

Mai.n wheel

Nose wheel 2,7 bar = 38 psi.

2,0 bar = 28 psi.

To fill up the brake

Brake fluid: ESSO UNIVIS J-13 or

AEROSHELL FLUID 4 I

You absolutely have to observe that only brake fluid

on a mineral oil basis is used.

Car brake fluid on ester basis will destroy gaskets

and tubes in a very short time.

March 9, 1983

Instructlons For Contlnucd Alr1orthlnc8s SCHLEICHER ASK 21 22

FOR TAILWHEEL OPTION ONLY

III.2 LANDING GEAR

?he landing gear consists of the shock absorbing main

wheel 5.00-5 and the non shock absorbing nose wheel

4.00-4. The traili-ng boom main wheel uses two hol1ow-

type rubber shock absorbers (type KE 1,20/95 core A

with mounting member, quality RTK 55).

?he rim ls a Cleveland wheel 4O7B (B), 5.000-5 Type III.

Brake: Cleveland brake assy 30-9.

Main brake cylinder: Master cylinder 1A-2A.

Tank for brake fluid: Below rear seat pan on LH side.

Main wheel: Tire with tube 5.000-5,

6ply rating.

Nose wheel: Tire with tube 4.000-4,

4p1y rating.

Tail wheel: Tire with tube 210 x 65.

Tire pressure

Main wheel

Nose wheel

Tail wheel

2r7 bar = 38 psi.

2,0 bar = 28 psi.

2r5 bar = 35 psi.

To fill up the brake

Brake fluid: ESSO UNIVIS J-13 or

AEROSHELL FLUID 4 !

You absolutely have to observe that only brake fluid

on a mineral oi1 basis is used.

Car brake fluid on ester basis will destroy gaskets

and tubes in a very short time.

Iqarch 9, 1983

Instructlons Por Contlnucd Alrrrorthlncs8 SCHLEICHER ASK 21 ?3

Fillinq up the brake

Brake fluid must be fil1ed up from bottom to top in

order to avoid air bubbles. For a simple fill up device

you need i,nstrument flexible tubing of about 2 m length

(=6,56 ft) and a funnel filled with approx. 1/4 I of

brake fluid at the upper end. The brake cylinder uses a

fill up nipple at its bottom. The lower end of the hosc

must be slipped onto the nipple. Wiren loosening the he-

xagonal head screw by one turn, a valve opens the nipple.

Hold up the funnel as high as possible so that the

brake fluid may run in with pressure. You absolutely have

to take care that no air bubbles get into Lhe system.

Therefore, always sufficient fluid must be also in the

funnel. Fill up untif the fluid in the storage tank

stands at 2/3- Now retighten the nipple and remove the

fill up device. Reattach the dust shield cap !

For the refilling of brake fluid the sma1l plastic

tank is taken out of its support. Open it and refilI the

brake fluid !

If the brake system has been emptled already to such an

extent that air has penetrated between master cylinder

and operating cylinder, fill,ing up must be done again from

bottom to top.

Air in the brake system will cause an extension of the

actuating travel at the airbrake 1ever. In consideration

of the flexibility of the flexi,ble pipes etc. one may as-

sume that there is no air in the system, if the flexible

travel does not exceed 50 mm = 1197 in for an actuating

force of 20 kg = 44 lbs at the ai-rbrake Lever.

I,'larch 9, i9S3

Instrutions For Continued Airvorthiness Schlcicher ASK 21 2l+

Bmke System

Supp_ty_lsd

Fitt up :lqbe

-------

h_pg$urelube

-ti!!-trp-rtpple Bteeder vatvp

Scews

brske

ryllr

for

pads

Instructions For Continued Airworthiness Schleicher ASK 21

lnspection and Feplacement of Brake Lininos

The linings must be renewed at the minimum residual thickness of

2.54 mm = O. 10 in !

The brake disc must be renewed at the minimum residual thickness of

4.242 mm = 0.167 in !

Reference: WHEEL and BRAKE ASSEMBLIES CATALOG, Component Mainte-

nance Manual, Appendix A, Fits and Clearances, A-1. Brake Lining

Wear Limits, A-2, Brake Disc Minimum Thickness, from Messrs. Parker

Hannifin Corporation, Avon, OH. USA.

1. Bemove wheel fairing.

2. Loosen the two 114" screws which are safetied by wire. Do not

unscrew the brake line hose!

3. Take out the brake shoes with linings, The linings must be re-

newed before they have been worn down as far as the rivets as

otherwise the brake disc will be damaged and the braking effec-

tiveness unacceptably reduced. To rivet the new linings in

place it is best to use a riveting tool designed for the pur-

pose. Alternatively, however, a hammer, centerpunch, and round

punch of not less than O 6 mm at the tip may be used.

4. Now replace brake shoes and tighten the two 114" screws and

secure them with locking wire,

5. Remount wheel fairing.

Brake linings and rivets to suit can be obtained from Messrs.

Schleicher. Orders must specify brake linings suitable for the

Cleveland 30-9 brake assy.

Tail Skid

Watch the wear of the tail skid metal plate and either reinforce it

in time by welding on sheet metal, or replace it by a new one. Re-

move the tail skid plate for the welding job.

The rubber tail skid is designed so that it will shear away from

the fuselage with strong lateral forces. lt may be glued on again

or be repaired using contact glue (Pattex). You must apply plasti-

cised fabric adhesive tape over the gap (glue joint) between skid

and fuselage in order to prevent long grass from being caught.

TN24 dated 04.05.92 (Juw) 25

fnstructions For Contlnued Alrsorthlness SCHLEICHER ASK 21 26

Tailskld

Check wear and elther reinforce in time the tall plate

by welding on sheet steel. or replace it by a ne$ one.

Remove the tallskid plate for the weldlng job.

The rubber tailskid is designed so that tt will shear

away from the fuselage with strong lateral forces. It

may be glued on again or be repaired by use of contact

glue. It is important to seal the glue seam between

rubber and fuselage vJith tape in order to prevent that

long grass will be peeled off or will cut into the seam.

Reinforcement of the taitskid ptote

Iaitskid ptote

Rein ment to be

sert nerd countersunk heod screws M6x 20

[[

B tN 963

March 9, 1963

lnstructions For Continued Airworthiness Schleicher ASK 21

l[.3. Radio Equiment

The front instrument panel is provided for the installation of the

radio. For installing the radio the mounting accessories and cable

harness supplied by the radio manufacturer should be used. Regard-

ing the layout of the instrument panel you have to consider that

the radio must be clearly visible and easily accessible to the

pilot in the flying position.

As to the clear visibility, however, priority must be given to the

flight control instruments. A suggestion for instruments layout is

given on the drawing for the instrument panels.

The Becker radio may be installed both horizontally or vertically.

The loudspeaker may be fitted below the rear instrument panel cover

on the LH side.

The swan neck (boom) microphone is mounted on the RH cockpit wall.

A support for a dryfit battery i.12V, 6.4Ah) is provided in the bag-

gage compartment of the left wingroot,

lll.4 Oxygen Equipment

Suitable bottle fixing brackets for two 4 liter oxygen bottles of

dia, 1OO mm are available as an optional accessory from Messrs.

SCHLEICHER,

When fitting the oxygen bottle(s), ensure that it is properly in-

stalled and securely anchored.

NOTE: Fitting of oxygen equipment causes only a minimal

change in the empty-mass C.G. position ! However,

it is necessary to re-weigh the glider and rede-

termine the empty mass C.G.

When flying at greater heights while using the oxygen system, it

should be borne in mind that any particular system may only be suit-

able for a limited altitude range. The makers' instructions should

be complied with.

TN24 dated 04.O5.92 (Juw) 27

Instructkms For Contintpd Airuorttriness Schhicher ASK 2l Zg

mirophorns on the RH cockpit uall

\ \V

\\)^

Inslallation of boom

.tf

-ts

lrt I

Microphone

neor to thc Ventitotion

Instructlons For Contlnucd Alrsorthlncss SCHLEICHER ASK 21 29

II1.5 PRESSURE PORTS & CONNEC?TONS FOR ?HE INSTRUMENTS

(see drawing on page )

Airspeed indicator: total pressure.

Altimeter: static pressure or without

any connection.

Variometer

fotal energy probe

Dynamlc pressure (pitot tube)

Static pressure

Colors of flexible tubinq

Pitot pressure: green

Statlc pressure! transparent

Capaclty fLasks: blue

fotal energy probe: red.

March 9, 1983

Instructions For tontinued Airworthiness Schhicher ASK 21 30

hessure Ports And Connections For TtE Instruments

tI-

tc,

6reen

mic pressure tPitoil

' r-: ?, '-ta

lnstructions For Continued Airworthiness Schleicher ASK 21

tf,

Instructlons For Contlnucd Alrrorthlnegs SCHLEICHER ASK 21 32

V. A I R W O R T H T N E S S L T M I T A I O N S E C T I O N

The Airworthiness Limltation section is FAA approved for

U.S. registered gliders in accardance with the provisions

of 14 CFR section 21t 29.

In addj.tion, this section es required by FAA Type

Certificate Data sheet

No. G 17EU and it specities maintenance requred under

14 CFR sections 43.16 and 91.163. unless an alternative

programm has been FAA approved.

LBA-approved on:

March 9, 1983

Instructtons For Contlnucd Alrvorthlneas SCHLEICHER AsK 21 33

Log of revisions

Revi s ions

No.

Pages

affected Description LBA approval,

s i gnature Date

March 9, 1983

lnstructions For Continued Airworthiness Schleicher ASK 21

NOTE: Damage to wing, fuselage, tail unit, and controls surfaces

must be repaired prior to the next flight.

Repairs beyond the scope of the REPAIR MANUAL issued by

Messrs. Schleicher must be carried out only by FAA-certifi-

cated aircraft repairers rated for composite aircraft struc-

ture work and only in accordance with Schleicher repair

methods approved by FAA.

V.1 lnsoection Procedures to extend Service Life

Proceed in accordance with Chapter Vlll.1.

V.2. Comoonents With Limited Service Life

Tow Belease Couolings

The Tost tow release couplings, factory fitted,

i.e. the C.G. Safety Tow Release "Europa G 72", or "G 73", or

"G 88" respectively, and

the front Nose Tow Release "E 72", or "E 75", or "E 85" respective-

ly,

have a limited service life (TBO) and must be returned to TOST for

re-inspection in regular intervals. The service life is stated in

the appertaining Manufacturer's Authorized Release Certificate.

The instructions given in the TOST "Operating Manual" or in the "Op-

erating and Maintenance lnstructions" for the tow release couplings

must be observed!

lnstruments

The flight monitoring instruments are

ice life limitations. As a general

should be complied with.

not normally subiect to serv-

rule, the makers' instructions

TN24 dated 04.05,92 (Juw) 34

lnstructions For Continued Airworthiness Schleicher ASK 21

Oxvoen Eouioment

For oxygen systems fitted, the relevant section of the appertaining

Manufacturer's lnspection Release Cenificate states the overhaul

time limit. Over and beyond this, the oxygen bottles must be re-in-

spected by a technical inspection institute every five years in ac-

cordance with pressure vessel regulations,

Soecial Servicino Procedures

At regular intervals of 6 years the brake line hose of the hydrau-

lic wheel brake must be replaced. Should this hose be found to be

in good condition, it need not be replaced, on condition that its

condition is checked at least every 10O flying hours.

TN24 dated O4.05,92 (Juw) 35

Instructlons For Continucd Ainorthlneas SCHLEICHER ASK 21 36

VI WEIGHTS AND C.G. POSITIONS

You will find the min. and max. C.G. Limits with re-

gard to the gllder empty weight on the Weight And

Balance Sheet ( see pages 48 EM)

Min. pilol weight front seat

Max. pilot k,eight both seats

70 kg

110 kg each.

Pilot welght always means plIot + parachute. If the

empty weight C.G. posltions are within the permisslble

range, Lt is assured that also the in flight C.G. is

within the permissible range provided that the load li-

mitations (pilot weights) have been observed.

The max. all up weight of 600 kg = 1"32O lbs must not

be exceeded. In the case that the empty weight comes

to more than 380 kg = 838 lbs, the max. permisslble

piloL weights have to be reduced accordlngly.

Weiqhts of non lift produclnq menbers

The weight of the non lift producing members Is com-

posed of pllotsr weights, fuselage, tail units, and

equipmenL, - wlthout the weight of the wings.

The weight 11mit of 4.10 kq = 902 Ibs for the non

llft produclng members must not be exceeded.

After repairs, repaintlngts or the lnstallation of ad-

dltlonal equlpmenL, at the latest however every 4 yearst

the empty weight and the C.G. positlons must be reestab-

I 1shed.

lvlarch 9. 1983

lnstructions For [ontinued Airuorthiness Schtticher ASK 21 37

VI.1

lrleiqht ond Balonce Sheet

Lnggoge

Dotum Poini Wing Leading Edge t8.Pl y=0,1'm

fr-l

hh(p t00:52 lnrizontal

6z'L,

rn =@'Lt

mox 90 kg Reor

+110 kg Froni

With pitot C.6. srm= 1185mm/46,65in

before dotun ooi

t{ith pilot C.6. arm

rt?50mrn I t+9,21in

= 80nm / 3, 15 in

befum &twr poini

-----r'S Eil$fr lBhf t,hSI

Instructlons For Contlnuad Alrworthlnc8s SCHLEICHER ASK 21 38

VT.z C.G. POSI?IONS AT ?HE LAST WEIGHT & BALANCE

lo.

tr{ -i ({

o, ll/|l

t{OC

,"lJ O

JJ UfI

(6 Orr

c ou

gro (u

.rlco

nr{ O

see also EM. page 48

>.c x

(du (6

.dO

tutr

ulFl O

q!d .

ru r{\ c

ooor..{

&AllE

I .lJ

>5 X

(6.c (!

o.U E

JJr

r0d

C'U

utc

r{ ut

+J9

C'lc-{ .

O(6\c

r{ o or*{

[qdJl E

..tJ ?

.c Ic 'r{

(rrc\

-{.-r g

{D.C E

3 tu-

$.a

O.U +r

E.d

tlUg

+rO

OJJ U

-cc

(l,} orto

.,u q{ d

.6Cr(0

o 3.q

March 9, 1983

Instructions For Contlnucd Alrrorthlnegs SCIILEICHER ASK 21 39

Weight, empty weight C.G. and payload have to be certi-

fied by an inspector on page 48 of the Fllght Manual and

on page 38 of the InstructiorFFor Continued Airworthlness.

VI.3 INSTALLATION OF BALLAST IN THE TAIL

It may be necessary to

order to get the empty

range.

install ballast in the tail in

welght C.G. within the permlsslble

The amount of the lead ballast which is required ls

establlshed eit,her by calculation or by a weight and

balance procedure.

Sultable cast lead plates are aval.Iable with the

company Schlelcher.

Remove the rudder.

By use of a knife remove the tailskid very carefully.

Grind off glue residues and other impurities.

From below drill a hole of 8 mm (0r3 in) in diameter:

centrically to the lead plate. The long slde of the

lead plate must be placed next to the vertical tail

unlt spar so that the plate will not turn.

Shorten the M8 screws, screw them on and safety with

a selflocking nut. Awasher must be added on each

side.

7. Reglue the rubber skid with contact cement.

8. After the hardenlng smooth the tail.skid/fuselage gap

and tape it in order to prevent the peeling off or

catching of long grass.

9. Refit the rudder and safety duly with castellated nut

and cotter pi.n.

March 9, 1983

Instructio*s For Continued Airuorihiness Schleicher ASK 2't &0

Instafiotion of baltast in the toit

Wosher O9,t+ 125-1,5

locking nut I'18

Screv M

lnstructions For Continued Ainvorthiness ASK 21 41

VI.4 WEIGHTS & TAILHEAVY STATIC BALANCE OF

CONTROL SURFACES

After repairs or repaintings the weight of the control

surfaces and their tailheavy static balance must be

checked. For this job the control surfaces have to be

removed. For the determination of the tailheavy static

balance M = P " r the control surfaces must be seated

in the fulcrum with as little friction as possible. lf nec-

essary, suspend them in their bearings with thread.

To measure P at the trailing edge it is best to use a

spring balance of 1 kg scale to which a small piece of

tape is attached. lf necessary, a letter balance will do,

too.

lf weights or tailheavy static balance moments are not

within the approved tolerances, you should contact the

company Schleicher.

Tolerances in weight and tailheavy static balance of

control surfaces and tolerances in play (backlash) of

control systems (controls fixed):

Weight tolerance

kg / lbs ailheavy static balanct

tolerance

cm*ko / in*lbs

Tolerance in play

(backlash)

Deoree/mm/in

Rudder 1.75-2.59/3.86-5.71 17 ,1 - 22.3 t 14.84 - 19.35 0.672"/3.88/0.15

Elevator 3.15-4.1/6,95-9,04 1 3.9 - 18.4 / 12.06 - 15.96 a.g2 l 2.84 t0.11

Aileron 2.85 -3,75 t6.28 - 8.27 17.4 - 22.91 15,10 - 19.87 0.8M'/3.01/0.12

March 9, 1983

Correction: 26.04.1999 / Juw

Instructions fur Continued Airuorthiness Schteicher ASK Z1 Q

Taitheavy stotic batonce meosurement of controts.

M = P- r (&N.cm )

Oeterminotion of P by use of o spring klonce or a lefier bo[once .

Instructions For Continued Airworthiness Schteicher ASK 21 43

V:1. CHECK I,ISTS

Ple ltieht Ckt

1. lhi.rr pbs safetr.ed ?

2. Rear }firg attachmnt ptns: is the safety ioclr nisibie alove

the piD ?

3. lkizsrtal tail udt pins safetied ? I3 the slEjng retamer

eD$€ed ?

4. Elevator $shrod ccffrected ? Safetied T:itb a smw dip ?

this is not aplicable fc Eliders fitdch us€ tbe autcoatic

el€vatc cwectien !

5. Ailerm pslrcds conn€cted ? Saretied ritb a slrim clip ?

Do mt forget tle sight csrtrol throt8h the ac!€ss hole

ccn€r I

6. .lirba]re trlsirrds cqmected ? Saietied rith a sgj-w clip ?

Do rpt iorget the sidrt ourtroi tlrrcrrgh tb aacess hole

ccroer !

7. drcck for foreign objects !

lt!€oql$ I

Ilitl alf. UIII&IEn qtd*rel€ase jairts G ulst be ahle to

t.rd tb brr !d!d by feeury ttu(r[h th slot jr tb hll

sntet. .lxt tb gQer f,lq[ffit d tb satetv l"* bf lllsh.

r.u it cn to dce !

Prc lble trf fuI

1, Paractlute ccnmtei to harrless ?

2. Sale* harness fasteued ?

3. Ai*rales locked ?

4- nria neutral ?

5. llti"Eter curr€ct1y set ?

6. C&cpies closed ard l6}ed ? Rear Cancpy I I

7. Eor flidlts vith mly file occlsant rmve the rear badr

rest I I

8. I€are yos tes l& tle pedal toe-straps I flelEri flatterr

tbe stres ! Htg€r of jamiry the p€dals :

1lHrlo.20 tlated october 15, i987

Instructions Por Contlnucd Alrrorthlncss SCHLEICHER ASK 21 LL

VIIl. PER]ODICAL INSPECTJONS

fhe following maintenance checks have to be caried

out periodically, however, imperatively at the latest

annually :

1. Check the whole glider - outside and inside where

accessible - for cracks, holes, dents and brhite

spots in the fiberglass.

The attachment hinges and pins must be checked for

corrosion, tool marks and play. If the front shear

pins of the wing,/fuselage junctlon show too much

Iateral play due to ground loopings, thin metal

washers must be added on these pins. The spar plns

must show some play, otherwise the wings possibly

cannot be rlgged at a1l with different temperatures.

Besides here the bearing pressure is so low that

there is no danger of wearout.

On the other hand the rear pins of the wing/fuselage

junction require more attentlon. In the case of

play (backlash) at these pins they have to be re-

placed in time agalnst oversize pins. The play at

these pins always should be within the tolerances

H7 / s6.

Good preventive nalntenance will increase eonslderably

the service life of all plns and fittings. Always

clean and relubricate the plns prior to every rigg-

ing. Do not misalign the pins t

Check aI1 metal parts for corroslon and, if necessa-

ry, repaint them. As primlng a zlnc-chromate prime

has to be used.

Make sure that there i.s no

attachment and in the tail

(see also above polnt 2).

4. play in the wing/fuselage

unitlfuselage attachments

ljarch 9, 1983

Instructions For Continued Airuorthiness Schleicher ASK 21 I+5

Check tbat there is no play in the fuselage/ring aDd fuse-

lage/tailplane connections (see also above Point 2.!.

The corditioD of all accessible beari.ngs. fittings, joints,

stops in the control linlages, and especi.ally the control

cables anA tosing hook cables, nust be checkecl.

The plastic tubes inside the S-shaped rudder pedal tubes

nust be checled for proper and tight fit !

The controls. iucluding the airbrakes, ilust be subjected to

aa op€rational test. and their control deflections nea-

sured.

7. If any coDtrol is not free-novinq over its entire range of

novenent, then the cause is to be established and e1i-

ninated.

8. Tbe condition of the nain landing Eear and tailskid (foam

skitl rith vear plate or pneunatic tailrheel respectivel.y)

incLudiDg tire, brake liniags, and rubber shock absorber

Bust be checked. See also that there is sufficient brate

fluid i-n the tark.

9. The toving hooks nust be inspected according to the nanufac-

turer's "operati.ons and maintenance instructions".

10. The pressure openingis (pitot antl statie pressure ports) on

the tusel.age, including their flexible lines, are to be

checked for b}octages and leaks.

Condition and function - if app1i.cable. naxj.[um permissible

operational tine - of all instrunents, VBF-Iransceiver

unit, and other equipnent are to b€ checked :

Tbe ritrg bendiag frequency is to be neasured and conpared

trith the stated value in the latest inspection report. For

this test the fuselage $ust be ri.gidly supported oB tro sup-

ports, in oriler to obtaiD conparable values; for the posi-

tion of the supDorts see the Survey Draring on page 29.

13. Check that the equipnent aDd iDstrunentation are in accord-

ance rith the Equiphent Inventory (Section XIV, AP?ENDIX of

this nanual).

14. lfter repairs or alterations to the equipnent the ner enpty

reight and tbe C.G. positloD are to be found by calculation

or yeighing, and are to be recoraleal in a sunnary of

lleights.

11.

L2.

Til-ilo.20 dated October 16, 1987

lnstructions fur Continued Airuorthiness Schleicher ASK 21 ,+5 a

1. SecuriBg

Past experj.ence shoreii that the quick-release connectors in

the airbrale, aileron anal particularly in the el"evator coa-

trol 1i[kages were incorrectly asseu]Led or that their as-

senbly ras even cospletely forgotten (as of serial no.

21205 the arrcraft was then supplied rith an autonatic ele-

vator connection). A sticler (fig.1) fixed to the fin and

the access hole cover, serve to renind the pilot of the cor-

rect assenbly. All quich-release connectors nust be secured

in addj.tiou by raeans of a spring clip (Fig.2), flitb the o1d-

er type of connectors the check hole nust be drilled to ap-

prox. 1,2 nn g for this purpose.

Fig. I

Fig. ?

* Spri.ng clip no.50030?71 can be ordered fron Alexander

Schleicher or fron the coepany A.$trth, P,o.Box L26L, D-713,8

Kflnzelsau.

(?hi.s part is also identical rith the foRD bralre securing

spring clip).

Tl{-!{o.20 dated October 16. 198?

lnstructions For Continued Airworthiness Schleicher ASK 21

2. Inspection

As experience accumulated in Australia has shown, the condition

of the L'HoTELLIER quick-release connectors must be checked on

every annual inspection of the aircraft, especially when it has

been operated freguently and from sandy airfields.

must not

inl; check this exceed O.15 mm

by using a wire

The tight seat ol

ed as loose ball

the thread area.

the

ends

the above diameter!

causrng of the

smallest diameters B to

not differ by more than

ball ends inside the fittings must be check-

are likely to break under bending loads in

Gap generated by an unscrewed and incor-

or owing to over-

lever part.

rectly refitted ball end

loading / wear out of the

NOTE: The Technical Note "Technical Data No. 1M.10.01A, lssue B

01i89", by the manufacturer L'HOTELLIER must be observedt

greatest and

found must

mm (0.O04 inl.

TN24 dated 04.O5.92 (Juw) 45b

lnstructions For Continued Airworthiness Schleicher ASK 21

lnspecting the taoino of the conilol surrace gaps

For aerodynamic reasons the control surface gaps between wing and

aileron and between stabilizer and elevator respectively are

taped where the control surface hinges are located.

Should this adhesive tape come off or be damaged, this may lead

to flutter! Therefore the sealing adhesive tape must be inspected

in regular intervals and where necessary replaced.

lf the adhesive tape needs to be removed for maintenance, or re-

pair purposes, or because of aging please observe the following:

as a replacement you must use onlv the Tesa tape no.46451, white,

25 or 38 mm wide, made by Beiersdorf AG, Hamburg.

Where other types of adhesive tape have been used, flutter cases

have been repeatedly reported!

Where a plastic fairing tape (elastic lipseal) has been fixed at

the control surface gaps, you have to observe MAINTENANCE INSTRUC-

TION C,

TN24 dated 04.05.92 (Juw) 45c

lnstructions For Continued Airworthiness Schleicher ASK 21 45d

vilr.1 INSPECTION PROGRAM TO EXTEND SERVICE LIFE

lntroduction

Fatigue tests on GRP/CFRP wings and GRP/CFRP wing

spars have shown that a service life expectancy of at

least 18000 hours may be achieved for these compo-

nents. However, as this test program did not examine an

entire aircraft made of CFRP and GRP, this service life of

18000 hours can be achieved only if the long-term air-

worthiness of each individual glider is demonstrated in a

special multi-stage inspection program (over and above

the mandatory annual C of A inspections).

Time Limits

1st Stage:

When the sailplane has reached a service life of 3000

and 6000 hours respectively, tests must be carried out in

accordance with the lnspection Program for the ASK 21,

lssue 2 dated 28.04.92, as laid down by Messrs. Schlei-

cher.

lf the results of these tests are positive, or if any defects

discovered have been correctly repaired, the service life

of the sailplane will be increased after the 6000 hours-

inspection by 3000 hours, i.e. to a total of 9000 hours.

2nd Stage:

When a service life of 9000 flight hours has been

reached the above lnspection Program must be re-

peated. lf the results are again positive, or any defects

found have been correctly repaired, the service life may

be increased to a totalof 12000 flying hours.

Rev.Nr. / Date SiS.

TN 29 25.07.03 Juw

Author

Kaiser

Date

March 83

lnstructions For Continued Ainrrrorthiness Schleicher ASK 21 45e

3rd Stage:

Before reaching a service life of 12000 flight hours an

inspection in accordance with TN no.29 must be accom-

plished. Depending on the results of this inspection, as

well as on the history of the aircraft and the evidence of

the percentage of aerobatics being below 12.5 o/o as

compared to the totalflight time, Messrs. Schleicher will

decide on a release to service for up to 15000 hours.

The lnspection Program must then again be repeated

and on the condition that the results are again positive, or

any defects found have been correctly repaired, the air-

craft may be approved for increase of service life up to

18000 hours.

It will be decided at a later date whether an extension of

service life beyond 18000 hours may become possible. A

research program which is intended to clear the precon-

ditions of this aim, has already been started with the

BMVBW (Federal Ministry of Transport).

lnspection Proqram

Please contact SCHLEICHER in order to obtain the ln-

spection Program for the ASK 21, lssue 2

dated 28.04.92, or any later issue effective.

The inspections must be carried out only by the manu-

facturer, or by an appropriately licensed aircraft repairer.

The results of the inspections must be entered into the

lnspection Program which is at the same time the report

of findings, where each item must be annotated with a

comprehensive comment, as laid down.

lf the inspections were carried out by a licensed aircraft

repairer, a copy of the filled in lnspection Program (report

of findings) which must be signed by the inspector, must

be returned to SCHLEICHER for the purpose of evalua-

tion.

Rev.Nr. / Date Sig.

TN 29 25.07.03 Juw

Author Date

Kaiser March 83

lnstructions For Continued Airworthiness Schleicher ASK 21 45f

On receipt and examination of such lnspection Program

Report SCHLEICHER will issue an "Acknowledgement of

Receipt" and send this back to the operator of the sail-

plane. Only on receipt of this "Acknowledgement" the in-

spector may certify the extension of the service life as

laid down in the lnspection Program, into the logbook and

the relevant sailplane's inspections papers.

The need for annual Certificate of Ainarorthiness inspec-

tions and overhauls (for German registered gliders $ 27

(1) LuftGerPO applies*' is not affected by this rule.

*) LuftGerPO = Aeronautical Products Examination Order

Rev.Nr. / Date Sig.

TN 29 25.07.03 Juw

Author Date

Kaiser March 83

fnstructlons For Contlnucd Alrvorthlness SCHLEICHER ASK 21 l+6

Special Checks

After rouoh landinos :

Check the landing gear suspension mount at the front

maln bulkhead I

Check the wheel fork for deformation; gear box ll

Check the control shaft above the wheel for deformation!

Make sure that the rubber buffers have not come over

the support discs !

Check spar tongue and fork for whlte areas I

Check the wing connections at the fuseJ.age t

Check the cross tube at the front main bulkhead for com-

presslon deformations I

Determlne wing bending oscillation frequency and compare

the value with that of the last inspection report. In

case of dlfferences by more than 5 % contact the SchLeicher

factory. (See survey drawing on page of the Instruc-

tions For Continued Airworthiness for jack up points).

After oround looos :

Inspect the fuselage tall cone at the transltlon to the

fin and also the attachment of the horizontal tai.l unlt

to the fin !

Check wlng connections at the fuselage t

lnspect horizontal shear web in the fuselage (between

front and rear main bulkhead) t

March 9, i983

Instructlons For Contlnued Airyorthlne8s SCHLEICHER ASK 21 L7

rx. LUBRICA?]ON SCHEME

Bearings : the slotted-sealed ball bearings are fi1led

with a longlasting grease and are capped off. So 1t ls

unnecessary to regrease thls bearing. The 14C6 self-

-aligning bearings in the pushrods and in the duralumi-

num rocker arms are also greased and covered with felt

seals so that they likewise do not need any regreasing

for a long period of time. The same applies to the ball

bearings of the pushrod guides.

The grease nipples at the controlstick and at the land-

ing gear rocker arm should be lubricated at least an-

nua11y.

The grease nipples of the control systems are accesslble

from the top when the seat cushions are removed. The

rear seat has to be removed in order to reach the grease

nipples of the landing gear rocker arm.

?he canopy locks and especially the emergency Jettison-

ing device in the front cockpit have to be kept well lu-

bricated.

Dirty tow releases are cleaned best wlth compressed air,

brush and through movement of the kinematics. ?hen re-

grease them with a spray oll or some slmilar agent.

March 9 . 198:1

Inshuctions For Continued Airrrorthines Schleicher A S K 21

LUBRICATION SCHEME

@ Cnoo and lubrirch lu rrery rigr4"

@ 0irort.mble ond tubricotr on onnuol inpclton.

Instructions For [ontinued Ainrorthiness Schleicher ASK 21 Ug

X. PLACARDS AND MARKINGS

1, Data placard wlth welght & balance dataJ

one placard each for the front and rear seat on the

rlght cockplt wall.

2. Flre-proof type plate;

0n the risht at the spar tunnel bottom.

3, Piacard statlng the approved Alrworthlness Categoryr

on the front lnstrument panel ,

4, Max. baggage compartment loadlng;

one placard each left and rlsht on the rear cockplt

wail close t0 the baggage compartment openlng,

5, Placard on the rear lnstrument panel .

6, Placard for "Pre take off check";

0n the underslde of the front lnstrument panel cover so

that the placard is vistble when the canopy ls open.

7. Placard on left side of top of fln;

Note: Thls piacard is cancelled if your giider features

the automatic elevator c0nnectl0n.

Placard ln the access hole cover I

B, Placard for tlre pressure nose wheel: 2,0 bar.

g, Placard for tlre pressure maln wheel; 2,7 bar.

10. Ai rspeed indlcator marklng .

11. G-meter marklng.

December 24, 1983 f N no.1'l

Instructions For [ontinued Airxorthiness Schleicher ASK 21 50

Setting of plocords

0ecember ?0. 1983 TN no 11

Instructions For Continued Airnorthiness Schleicher ASK Z1 51

For talll.{heel option only

X. PLACARDS AND MARKINGS

1. Data piacard with weight & balance datar

one placard each for the front and rear seat on the

rlght cockplt |,lall.

2, FIre-proof type plate;

0n the right at the spar tunnel bottom,

3, Placard stating the approved Alrworthlness Category;

on the front lnstrument panel.

4, l'lax, baggage compartment loadlngJ

one placard each left and rlsht on the rear cockplt

wall close to the baggage compartment 0pening.

5, Placard on the rear lnstrument panel.

6, Placard for "Pre take off check";

on the underslde of the front lnstrument panel cover so

that the placard ls vlslble when the canopy is open.

7, Placard on left slde of top of fin;

Note: Thls placard 1s cancelled lf your gllder features

the automatlc elevator connectlon,

Placard ln the access hole cover !

8. Placard for tlre pressure nose wheel t 2,0 bar,

9, Placard for tlre pressure main wheel: 2,7 bar,

10. Airspeed lndicator marking.

11 . G-meter marking,

12, Placard for ttre pressure tall wheel: 2,5 bar,

December 20, 1983 TN n0.11

Instructions For [ontinued Airworihiness Schteicher ASK 21 52

Setiing of plocords

December 20, 1983 TN n0.11

Instructkns For Continued Airvorthiness Schteicher ASK 21 53

Segelftugzeugbau A. &,hlekhcr @nlr,u so n

Modcl *rp,l no.

DATA PI-ACARA

Aprond fu:

thx. slrtd br colm oir fZttEril-Ft

lihx. spocd lor rough oir | 200 kn/hl

Itax. m@ruvcring spccd Vp Lte0 tl4la)

tlox ocro lou specd i; f lso ir/i1

l,loxvinch lounch sp*d iw 17fi kz7A

WEIaHT AND BALANCE

l,lin pyload lronl seat LC

Mox. poyload front seal kg

llax. pylood reor seot kg

Boggoge in vitryrots mox. 2 xlo kg

he Takc ?ff (lteck '

1. Cootrals cosy to qarotc ?

2. Airbokcs tocked ?

3.him h llto cenler psilion ?

l.furochutc orrd sdfety harness

fostaned ?

5.Altimeter odjusted to field heigh

or to zero ?

6Rodio "ON"ond odjusted to

proper lrequency ?

7 Eoth canopics locked ?

Instructions For Continued Airuorthiness Schleicher ASK 21 54

Attentian ! Energency fuitout !

o] Pull back both canopy sidr-/oclts and push

canopy upwords.

bl Undo sofety horncss.

c ) 6ot up and bail oul.

d) Wilh manuol chulc seize releose grip and

pull out enlirely al ter | -3 sec.

A. Sc hleicher

6af Mnhqrsrn

Hodel : ASK 2,

Srnal no.' 21 XXX

nagisttotion

,lode in llrbst Gcrnany

For equipmcnt witlwut

g-mctcr ond bottom strap.

For quipment with

g-ileler ond battom strop.

Instructbns For Continued Airuorthiness Schleicher ASK 21 55

Airspeed indicqtor cotor codes

43-9? kts / 50- 112 nph

6reen orc 97 - 151 kts / 112- 174 mph

Yellow arc

6round, mat-btack

Color odes and tetter in

tuminous point.

0 -meter cotor codes

o) Positive range

Yelton orc frcm +

b) Negative range

Instructions For Continued Airuorthiness Schteicher ASK 21 56

!, i!*i

Instructions For Contlnucd Allorthlness SCHLEICHER ASK 21 57

XT. REPATRS

On principle repairs must only be

turer or by a certified (licensed)

facility.

For exceptions see repair manual.

tact the manufacturer !

xIr.

made by the manufac-

technical aviation

In case of doubt con-

z- 1\

MODIFICATTONS

Minor modification

A modification to the aircraft which has no influence

on its airworthiness and is feasable by using standard

working methods, may be done without prior notification

to the Civil Aviation Authority,if it is done in accor-

' ri $tu,e'tivil Aviation

dance with a technical note !ssued.rp

Authority. -L...1,.' I

: --",

Ma i or modi f ication :f'

A modification to the aircra{t--whi'ch-has .l-, inflr.n..

on 1ts airworthiness or requires a change of the opera-

tion instructions or of the operation limitations or is

not feasable by using standard working methods, must on-

1y be done by a certified (licensed) technical aviation

facility. The major modification must only be done in

accordance with technical documentations which were sub-

ject of a supplementary type-approval under the test re-

gulations for aircraft.

A supplementary type-approval is not necessary, if the

major modification is restricted to only some single

units. Prior to the carrying out of the major modification

the proof of the airworthiness must be furnished in ac-

cordance with the test regulations for aircraft.

March 9, L983

InstructLons For Contlnued Alrlrorthlnegs SCHLEICHER ASK 21 58

XIII. DESCRIPTION OF SYMBOLIC PLACARDS

c 0 \* Rudder pedals adjustment: grey

knob on RH slde of the console.

To adJust pedals backwards:

Take your feet off the pedals and pull pedals backwards;

then let go the grey knob and load the pedals in order

to lock them.

To adjust pedals forwards:

Pu1l grey knob and push pedals forwards with your heels;

then let go the grey knob and load the pedals in order

to lock them. Airbrakes! blue lever in the LH

arm rest; pu1l to extend airbrakes.

Trim: noseheavy.

Trim: tailheavy.

Tow release: ye1Iow knob LH below

canopy frame.

OPEN froat canopy;

Hove rbite levers LH and R[ on

canopy frane backxards.

EMERGENCY JETTISONING of front cedopy!

Pusb lever rith red fLat knob to the left

L:a\

t{ay 29,1984 ?N no. 15

Inatructions For Contlnucd Alrworthiness SCHLEICHER ASK 21 59

OPEN rear catropy

JATTISONING:

Hove rcd lcvsrs

fraoe backrards.

Ventllatlon

anVor EMERGENCY

tH and RE oa caaopy

Prior lo loke off check the

proper engogemenl of the

locks! torvord:{ocked

this placard must be fitteC in

the front and rear cockpit in

fulL view of the pil-ot.

May 25''t984 EN no.15

Instructions For [ontinued Airworthiness Schteicher ASK 21 60

XIV IPPEI]DTX

XIV.1 Equipnent Liat

llinlouq couioacut

1. Alrapcod indicetor

r. Ylatcr cv 6005 50 - ,5o kl^

b. tuL Ps oE p - )Ja k;a/h

2. Altirtrr

r. Iltrt* 4 EX 6

b. Yiatcr { FGE 10

cr WL U-12 S

,. Sefoty hunctr

Gadrtagcr Bagu v-Br/1

Schusu IJ-C/V

Bonr I-B./V front

Bogu I-A./V rear

Additional ainiaun cqulpuaat for aerobatlca :

G-actcr BA ??A L

Addltional EiriEu! rquipocnt for cloud flyiE8 :

tura & bank lndicator Apparatebau Sauting YZ*4O2/

,1.

Colpaaa : LudolPh 9K 5

- Luitol3b Pf 15

w, Bs-1

?7,L *1r/KJ

VIIP- t rauac circ r

r. Dlttrl $e 1r/25

b. Dittrl ?so 16/2,

c. Dtttcl fSG 40 S

d. Brcl,cr ^R 2@8/25

.. Bcel,qr AR eOO9./e5

f. lviosic Dittrl AIR 72O

Tt{-No.20 dated october 16, 198?

lnstructions For Gontinued Airworthiness SCHLEICHER ASK 21 60

XIV APPENDIX

XlV.l Equipment List

Minimum eouipment

1. Airspeed indicator

a. Winter GW 6005 50 to 350 km/h

50 to 350 km/tr

50 to 300 km/h

0 to 300 kmlh

50 to 300 kmlh

50 to 300 km/h

b. PZL PS 08

c. winter 6 FMS 4

d. Winter 6 FMS 421

e. Winter 6 FMS 5

f. Winter 7 FMS 4

g. Winter 7 FMS 5

2. Altimeter

a. Winter 4 HM 6

b. Winter 4 FGH 10

b. PZL W-12 s

d. Winter 4 FGH 20

3. Safety harness

a. Gadringer Bagu V-B/1

Schugu ll-CA/

Bogu l-Blr' vome

Bogu l-Aly' hinten

b. Schroth

b. G-meter

c. G-meter

d. G-meter

e. G-Meter

f, G-Meter

BM 770 L

AM 1O

BM470-2

BJ 10 - 2

G 510

GM510-2

Additional minimum equioment tor cloud flvinq

Turn & bank indicator Apparatebau Gauting WZ - 44431

Compass Ludolph FK 5

Ludolph FK 16

PZL BS.1

PZL B131KJ

VHF - transceiver

a. Dittel FSG 15/25

b. Dittel FSG 16/25

c. Dittel FSG 40 S

d. Becker AR 2008/25

e. Becker AR 2009/25

f. Avionik Dittel ATR 720

g. Dittel FSG 71 M

March 9, 1983

Correction: 08.07.2003 / Juw

Blatt1 vonl ASK 21

Maintenance lnstruction

Wheel-Rim Tost Penta, lssue I

Alexander Schleicher

GmbH & Co.

Segelflugzeugbau

D - 36163 Poppenhausen

Subject Alternative rim for main wheel

Applicability: ASK 21, TCDS EASA.A.221,

variants ASK 21 and ASK21Mi, all serial numbers

Reason: The rim Tost Penta 125 - 1/i' can be installed instead of the rim specified in the

Maintenance Manual (Cleveland 40-788)

Action: For every rim model there is an appropriate set ot space bushings, which are threaded onto

the axle on both sides of the wheel. Vvhenever the rim models are exchanged, the space

bushings have to be replaced, too. Furthermore, a tyre tube with short valve must be used.

The brake calliper retains unchanged.

Material: For the Tost-rim:

Part no Pcs Denomination

210.21.0027 Space bushings for Tost Penta 12S1%'

(Left: I = 37; Right: I = 31)

210.21.0028 Clamp washerfor Tost Penta 125-17;'

Tyre tube with short valve

Part no Pcs Denomination

210.21.OOO5 Space bushing leftf. main wheel (l = 29)

210.21.0006 Space bushing right f. main wheel (l = 30)

210.21.0007 1Space ring f. main wheel (u35110 - 10)

210.21.0008 Clamp washer f. main wheel (O40110,1 - 2)

ITyre tube with short valve

Notes: none

Poppenhausen, 01.06.10

Alexander Schleicher

GmbH & Co.

i.A M-e;

(M. Greiner)

DOEIil{Srf IEA

No l 10.01

Rev:B EO8.A

.NSTRUGTIONS FOR THE MAINTENAI\ICE

L'HOTSLLIEH BALL AND ST,\TIVEL JOINTS

EI5:BORISI'S DU DOAN@|!!

LtsEE DES D8stltrt8f,rtts

IruisL'HOTEI,LEBS.A.

93, acorre Chirles De Csullc.- 94170 BOIS COLOMBES

Tdl.(1X2.42. 13.94 T6hx. 61 r l53F IJIOTAIR TeEcopic (t)47.60'0?.0?

nEv. oI"E OE.}E? DB $e $ISE A JOUR. EED. aElx.. 8EAP.

11/85

02le6

01189

o? 192

0.3194

cteatl-otr of dorunerrt

Bspreacntatl.oa of 1 .rrivsl

Adruactioa of Rtg.l illd E.lE.2

IrpdattGg of functlon of c8147

UldrtitrE follor.irg DEI229-EH

lLrD

l{.tD

t{Jb

llrD

XJD d

JI{B

JI'B

ru8

Jr,t8 r

ne#.

B.E. B.C

0.a. r.c

Q.C. C.B

0R. +1 EX.

1 BX.

1 Ef,.

TRODUGIlOt{ 1 EI(.

mtfGftL'B fouaElh tElrl*r.iltr

DOCU}{EHT THA

lils : 1O. 01 nrsrBggtrrgr{s ron r8E uellmB|escE

LrBOlggttJIEB BilLrr eI[D Sf$IEIJ ifo$fllt EO8-A

cs{PoExlror uo EoemaEuE

PACE rND. Ptct IIID. FA@ INB,. PICE I}ID. ?tcr r$D,

tIa Esox E1E2E

sUHirrI!

1 - FrEIEtf,!fiE xf,D 6A!ig!r r{A$*IEEAI|CE frSAf,lrellONs

2 - BE*IODICET CTa1EX

:.T. FREE I'OIIEilEN:8 OT EEE EAiiL U*AO lrBE AOUBIilC

2,3. Elr.& SPIEBICXTf r'lEaSUBElsN:t {S.G fig. 2}

2.3. BII.&'IEERETD gEECf,

2.{. afitVllt q[SIritr CEEqf,

2.5" r{Eif,s[ilrl.ErlI Or 18! tacrES IollEB ?eEt Pro.rEq[rEf, lf,uEE

IFsEtI8ar oF Exr'S{IVEL oll El8 EHtiL (si. fig. l}

2.5. 6 T TE I,Iffi BEII{EEI DEJTVE RO' IITD 8TTl'EE.

2.?. $|r!rg, a58I .OPEneEIOtt CEECX

RED. ;8E DAJE I (BlS4

PAGETSOM MD.:E

IrubUEOTELLIERE A.

93, evaruc ehedes Ds Grullc ' 92!7O BOIS COLOMBES

T6t.f lN2.4l. 13.94 Tdler 6Il l53F IJIOTAIE: fd&opic{l}4''69'07'$?

ffigL lffl*.*Gl,

DOCTI!{E}I!' IUil

l{e ! 10. 01 rlr8rBuclroHs roB lEE uBIUTErrnNcE I E08-A

LtEOTEIif,fER BA!Ir BHD AWMII ifOfNEA. I

tha rotrtio[ 6f thr trr'lvel iaoEad the ba!,l firat tre iiaap r*lth rs!i..tl,ng sticngh,

. dqc to 6l,Br-6u!n !ric!ton8, Co,rrcqucnlly lt l. ltrartdetory t6 lubricits the

'reLv.l/brll rE y. Thls lulttficatloa ioust bE alon€ rftBr cleaaing a,ad bef,or€

.r..Ebly, wLth a non col.d catgulating Ercrsa.

8E ! ESSO purto.e {general u6e} t

Spfly containing ollt ctraiched ]rlth Elllcon. (recomEndsd for Bs6€mb1l.si

exlto*ed to.smd ar 6gher abreslv. Eaterlals,.

ft lE mandrtory to eellfy, .ftBr eg6h ert€nblyr th€ correct locrEion of, thc.bal.l,

in the errlvel. lo do Eo, a locetlon hole l,r drilled Ln the lockca. t{hTn tbB

'-' a€Eeilbtry l,s good, th6 hole fturt bG visible e,ld rnuBt a[eble to lnsaat tha pi.r -Er

r€f, &'E 140-31, or othEr d.vl-ceE, llnhed to the. locher only.

2 - PERIODICTL CEECE

Durlng the anDual visit oJ' $g later than every 50O Slight hauss. it ir $e€6.rsery

to verJ,fy balla aad gl,iqrls as followa. !

2.1, reEr Mo r.E&! or GEs BlI.Ii r*to rEE roustlte

- Clreck that th€ bal}, ursvr f,6€ 6! frletlon lFlnt.

- Check th€ alr€uler d:lr]1.c@n!.

- Check that tlrare lg no crack" at tlre bage €f, tbc b81l

2.2. BBIIL s?EEfi,lstlt HET!IaBEI{3!U! (s.. fig. ,}

Th€ varlrt-i.on betw6a)l eeveral nr.e€u?e. of the ball dl,an€etr rrtlEt not €xeeed

0,1 m.

tblE check aLE iB to detaet en alrnordsl'ball rycer.

2.3. BM.I, EBABD CEECX

Eo th!6td darurE6 l"e acceptablc. Dt ritrg rer66embl,y ehE EEllar lruat b€

.FGrfEctly !6t on itc baEe. It la eand.toly to trtx thc ball ln p6siti('n wltb

an rdeqlratE loclLng devl,c€.

2.4. SWrEEr. Vlflrl,r eEECS

N6 defornatlon or pennlag fn ball location or l,a the loc,riag doyico scat,ir

acceptable.

2.5. lrEtstR8$Em or rE rocxEe. Lol{EB ERtu[ t8otEcrlots er:ssf, agsElilBLt or lEl

A$MI. Ol( tE Eer& (sE! .tiE. 1)

thi. proj€ctlon Eust be hiqher tban 2 fttr.

the aj.tt ot thlE requirrment is to v€rlfy tbe efflciercy of the eutonrstic

takB uI, claara$ce

Louis L'IIOTELLIER. S.A,

93, avenueClrartesDo Gaulh -92?70 BOIS COLOMBES

Tgl-(1112-"12. 13.94 T€le* 6l I 153F LIIOf,AIR Tdldeopic (Ila?.60.07.e7

RED. : BE

.FAGE r IDAIE r 0X/9,4

IHD. r E

fiorurErr muEEr! tflrf5g *tnoblE $r{,{fii:BnE rrB

BOCIIHET{tr TIIJI

No:10.01 IIIST'RUCTTO}Tq I,OB TNE UAISAE}IANCE

[reor8r,LrER Bn!I, ]fiD SUXVEI) irort{ts8 EO8.A

2..6. eEcE oF EEE lIilE aEElEEr DBIVE aoD aND SrvIgEEr

In the ca6. o! aI} .dlr3tabls. swlval, r€rLfy th.t tlte }ink betweatr

B(ivsf and drlve, rod is ttght and Droperly Eecurid by 8a r'lequ4te

lecking dalIj.ee"

2.?, SffiVEr. ASav OFBEffrrOr CEE(X

seat or IsskBr : no clan?log, diro to oxlidatiot sr otier reaton, i.E

aeerptsble.

If aft6f the6e ve?ifis6tion3. ,one of the sboYs ahtsek i.{ oue of tolstanEG? it Ir

nrrldatory to r€plac6 both ball and suj:vsl'

ne+erlhelsss it ig. r6saosl6'nded Co t€9lace thlg 8ss€dlbllr every 10 yeara or av6ry

3OO0 fligbt hoqrs.

IMPORTf,ItrI X TE

Any dsfection paru5 may be returned to Ets I.eult l'tfOIELLfER for letdmical

inve€tigat.ion.

rrc.1

FTG. 2

H-Bl<q{ ttr'

Louis L'HOTETLIER S'4.

93, avenue Ctadss Do Gaslle ' 9A?O BOIS COLOMBES

Tdl.( I )42.42. I 3. 94 T'ilex 6 I I l53F LHOTAIR Tdl€coPie ( l)47.60.07'07

RED.: BE

PAGE: 2

DATE:05/94

IND.: E

rffiffiltmffi14

Sheet:

lofl All FRP glider models

Maintenance Instruction

dated 19.06.86

Alexonder Schleicher

Segelflugzeugbau

6116 Poppenhousen

Removing play betvjeen the sockets and bolts of the wing-fuselage

transl!ron

Longitudinal play between the four sockets in the wings and

the bolts on the fuselage (Note: for the ASK 21, only the

socket/bolt connection front in the wing nose/fuselage tran-

sition) leads to disturbing cl ick-c1 ick noises when the rud-

der is operated, and can result in unpleasant tail oscilla-

tions at high speeds.

The play is eliminated by fitting metal washers of 422,5/32-

thickness according to the extent of the play. By testing,

the play must be reduced such that the wings can be assembled

still properly - this applies to a normal temperature of 20 oC.

Depending on ihe extent of the ptay, the metal t{ashers can be

fitted under one or more bolts.

The bolts are slid out of the fuselage cross tubes by fitting

a steel rod through the hole in the opposite bolt, and driving

the bolt out from the inside t'lith a hammer (see sketch below).

After fitting the metal washer(s), it should be possible to

drive the bolt back in place, using only a 500 s ( - 1 lb) ham-

mer and a few blows. If it returns too easily, then knurl the

seating area slightly untii a tight fit is obtained again.

Poppenhausen, June 1 9, 1 986

ALEXANDER SCHLEICHER

GmbH & Co.

Ax;(,.

€ St.ihflil.. Ftud Sofriwdruck" 09 6rAt ,3

Sheet 1 of4 Maintenance lnstruction

PAINT CRACKS

Alexander Schleicher

GmbH & Co.

Segeflugzeugbau

D-36163 Poppenhausen

Subiect:

Tvpes affected:

Comoliance: 1.

Reason:

Paint cracks on fiber composite gliders.

ASW 12, ASW 15, ASW 17, ASW .I9, ASW 20, ASK 21, ASW 22

ASK 23, ASW 24, ASH 25: ALL variants and all serial no.s.

lf deep cracks which go down to the fiber composite structure, are

found on the glider, the glider must be presented each year to the

manufacturer or any other licensed aviation station, who upon ex-

amination of the glider decides whether the glider can be contin-

ued in service fol| year more or whether the repair must be done

at once (see point'Ac'tion A.").

lf hairline cracks which run only in the paint surface, are found on

the glider, the glider shall be presented at the latest after three

years annually to the manufacturer or any other licensed aviation

station, who upon examination of the glider decides whether the

glider can be continued in service for 1 year more or whether the

repair must be done at once (see point'Ac{ion B."). The 3 years

extension applies only on the condition that the maintenance and

care of the aircraft is no longer neglected during this period of

time and that the gliders are no longer stored outside;

The Flight and Maintenance Manuals for SCHLEICHER-gliders con-

tain insistent notes concerning the detrimental influence of moisture

and sun radiation on the aerodynamic paint surface quality standard.

Herewith we point out emphaticallv once aqain that every owner is

obliged to observe the flight and maintenance or operations manuals

of his glider in all points, and this refers also to the relevant notes on

the care and maintenance of the glider.

lf these notes are contravened, the result will be sooner or later - de-

pending on the climate - damage to the paint surface quality.

lnfluence of the two factors

p!g!6 and UV-radiation:

To begin with, generally an enlargement of the waviness of the finish

develops - mainly on the wing and tail unit skins - caused by penetra-

tion of moisture. On the occasion of performance measurements (ac-

complished by P.Bickle, R.Johnson and the German DFVLR/ldaflieg)

it has been demonstrated repeatedly that the larger waviness leads

already to considerable performance loss which is all distinctly no-

ticed in competitions.

Sheet: 2 of4 Maintenance lnstruction

PAINT CRACKS

Alexander Schleicher

GmbH & Co.

Segelflugzeugbau

D-36163 Popoenhausen

A competition pilot will always be anxious to preserve or restore the

performance of his glider to its full extent, but unfortunately owners of

iraining and instruction gliders are generally of the opinion that they

may accept such a performance loss with those gliders. This is regret-

tabie in the view of the manufacturer because he makes all efforts to

build and supply also these gliders with a clean aerodynamic surface.

The valuable production time used to this end is then possibly use-

lessly provided.

Owing to the UV-radiation the gel coat of the paint surfac,es grows

brittle and shrinks; at the same time the UV-light destroys paint ingre-

dients. So moisture (rain, dew) working in on long term wlll wash the

decomposed paint ingredients out off the paint. The paint starts chalk-

ing and gets hairline cracks owing to the concurrence of embrittle-

m6nt and shrinkage. Furthermore, these hairline cracks gather dirt

which through its aggressive effect and its stronger heating-up from

sun radiation further precipitates the degradation of the paint. Owing

to this the intended protective effect for the fiber composite structure

against moisture and UV-radiation is no longer granted.

Certainly a good care with hard wax can slow down the above proc-

ess distinclly, but it cannot be stopped completely. For this reason a

repainting of the aircraft will always become necessary at some point

of time.

However, we point out explicitly that paint cracks - even deep cracks -

do not represent damages to the aircraft structure if as of their first

appearance immediate correcl maintenance and care is given fur-

thermore to the aircraft.

As all the outside skin of the aircraft is dimensioned for stiffness, there

are no critical mechanical strength problems, even if some cracks

have gone down into the fiber composite structure and have already

attacked the resin matrix base.

The unknown ageing effects caused by the influence of moisture and

UV on the unprotected fiber composite structure are more dangerous.

Those paint cracks as reported from customers in USA and Australia

do not appear here in Europe or they develop so much more slowly

that a paint crack repair has never yet been carried out here at our

works. Accordingly we have no experience of our own with such re-

pairs.

ln this connection we point out expressly that for the mentioned cases

in the USA or Australia an absolute "zero" care of the gliders in ques-

tion added to the "climate" factor; besides these gliders were exposed

to the weather almost continuously and without any particular protec-

tion - very often day and night.

Sheet:3of4 Maintenance I nstruction

PAINT CRACKS

Alexander Schleieher

GmbH & Co.

Segalflugzeugbau

D-36163 Poppenhausen

Action:

Material and

drawinqs:

Weiqht (Mass)

and Balance:

To repair the paint cracks, these have to be removed generally by

sanding them down to their ground. But in doing so, the fiber compos-

ite struciure lieing under the gel coat should not be sanded on. Thus

the sanding job is difficult and, therefore, relatively expensive.

lf deep cracks are concerned which go down to or into the fiber

composite structure (it is assumed that they result from large and

rapid temperature changes as found e.g. with wave flights !), and

if a repair is decided to be necessary, the paint material has to be

sanded down to the fiber composite struclure carefully and the

area affecled must be repaired.

ln case that the resin matrix base of the fiber composite structure

is already damaged, one should consider peeling off and replac-

ing the damaged fiber composite layer. This work is possibly eas-

ier than the careful sanding job.

lf hairline cracks are con@rned which run only in the paint sur-

face (and which presumably result from bad maintenance to-

gether with continuous UV-radiation - i.e. gliders left outside with-

out any protection for a long period of time), we recommend to

remove the paint material from all areas aftacked by sanding on

them down their end and to repaint these areas. The sooner this

measure is taken, the less the work expenditure.

On the subject of rebuilding the paint system with materials available

in the USA as well as on the subject of how to rebuild the profile

(which is a must for high performance gliders which are to be flown in

competitions) R.H.Johnson, Dallas Soaring Association, has written

several articles published in SOARING magazine. We advise to con-

sider in any case the repair experience accumulated in the USA.

For Europewe suggestto spraythe sanded surfaces firstwith polyes-

ter fillers, to sand them again, and to re-spray them finally thinly with a

white paint system on a Polyurethane basis which should be aircraft-

approved.

See chapter,Action".

It is necessary to redetermine the mass and C.G. data after repaint-

ings,

After repainting of control surfaces and flaps special aftention must

be paid to their tailheavy balance moments; these data are given

in the respective Maintenance (or Operations) Manuals of the gliders.

Sheet: 4 of4 Maintenance lnstruction

PAINT CRACKS

Alexander Schleicher

GmbH & Co.

Segelflugzeugbau

D-36163 Poppenhausen

lf in the case of older glider models such data are not contained in the

manuals, then the mass of the control surfaces and their tailheavy

static balance moment must be determined gi@.lh@t_i9b, and

must be readjusted after the repainting by *,5 o/o.

Notes: 1. The action as per this Maintenance lnstruc'tion must only by ac-

complished by the manufacturer or by a technical aviation ser-

vice station holding an appropriate license.

The present Maintenance Instruction PAINT CRACKS dated

June26, 1989, supersedes the previous Maintenance Instruction

dated 15.07.87.

Poppenhausen, June 26, 1989

Alexander Schleicher

GmbH & Co.

Gerhard Waibel

The translation into English has been done by best knowledge and judgement; in any case

of doubt the German original is controlling.

Malrltananca ln3tflrcllDn AAlcrtandcrSchlolchcr

oh$a.&e.

s{ffi{Ed{bru

D -elt6Pq.nharlen

3ubfuct:

Alledro:

Comoliaaca:

Faasonl

R.-adiusting the Eirbrakos.

All ASK 21 serial no,s.

As required.

tt is impo*ani to chsck in regular intervals the look-

ing of dre alrbrakas. Each alrbrake has its own toggte

in th6 wing. For thir rBEon lt must b€ ch6c*sd that

both airbrak:s lock simultansously and secrurely.

1, This is chdcksd by connocthrg ths brakes individually

and rmr&ing tte point on th6 operdhg lever gae in

*re cockpit 6t which the linkage's daad e€nter oe,

curs. Bofi dead Boints should be within 5 rm {O.2 in}

of each other ard, in the loeked stgts, the individu-

al braks sholltl still heve 10 mm .ot frea movernent of

*re lront lever loralards h the gate. ;

2. lf you obsgrve &st the alrbrakes do irot havs an oven

trver-66nter .loclg tha toggle ovcr dead center must b6

reddiusted, This must !e done wth' the alrbake push-

rod disconneGed from t'le HOTtLllER ball qulckdiscon-

rECL

As shown in Fig.t ths shon pushrod (ll lr o ba dis-

connactsd fmm fte toggle crank (2h back off the

lock-nst (3l and scr€w out tha pushrod lll by 1/2 to

1 tum. Re-connect in the revBrse order and check

eguin as desqibsd ufidrr pdint 1,1.

g. lf tlre air&rrkos edll do not h*re srtficient dead

lock force, peel a little srt rtro toggl€ stop

block {4}. u$ng I purrfi carefully rsrnow sdne laysrs

,rorn tfie s$f hlock {4r; then sgain rssdiust the air-

bnkes as descdbed under polnts 1.1 and 2.),

,'-

N€rr, safily nut NM E, DIN 980€, if n€€ded.

Ac{ion:

Matcrial:

Poppenhausen, Marctr 23. 1987 ALEXANDER SCHIEICHEH

,., Gmbll & 9o,

w-#,\#

LW. Jurqg#.

Ths tranrlation into English has been done by best knowledge and judgernent; in

any case of doubt the German orighal is conrolling.

Makrtenance lnstltrction A AlelrnderSchbichsr

Gillt.lrOc

S.gde{EaEE6t

O - 8416 Popp6$atEsr

Fig.1

r-;+

-.1- .l

.€ EXrENst0N

\ HI6HT

t4i

-!E

9i:

gE€

-E t

iEt

irE

c'5 I

!iE

{!€

3..

t:3

!9!

i€i

r; i

EE 9

EEi

lii

c5P

eEr

.3i3

FE=

sg-c

SEEET:

1of1 tsf, 21

ilaiDteDance lD6tructiotr B

Issue I

Abrrndrr Schhichcr

GmbH E Co.

S€g.lflugz.ugbu

D-6itl6 Poppenhausen

Subisct:

lf,fectirc-:

lctio:

InstallatioE of oversize elrag Dins

All serial no.s ASK 21.

1- Derig the gliiler,

2. To be abLe to safely reaD the nen holes the safety

clips bave to be renoved at the root ribs

3. Then rig the glider ae usual atd supDort the flings by

use of ring stanils or equivalent (sar horses, trailer

dollies) such that the drag pins can be easily re-

noeed ard inserteil.

4. Tale one ilrag pin out, reaD the oversize bole antl

insert oer ilrag Din.

5. Do the sare on the otber siile.

5. D€rig the glider.

7. Eix the safety clips again at the ner drag pins.

fote: ?he folloriBg piD ilianeters are available:

11.95 ru, 12.0 En. 12.1 Dn, !2.2 nD aud 12,3

Poppenhausen, .ruly 4, 1990

}I,ET.ETIDER SCHLBICEER

GDbH E Co.

A-a-*dA;/,e

doerharil lfaibel-

The traDslation into EngliEh bas been done by best hDoflledge and judgenent; in

atry case of doubt the Gersan original i3 controlling.

lnrl:

l of 6Aa[ul

fitah$nilcr lnstructlon C

lsruc I

ALrrnd.r8chhicfi.r

ffixaod

s.edfFughr

D.G.i6FolD.nh$rt

&rbhEt:

Affect&ro:

Rexonl

Acdon:

Fig.l

Fixlng tur th6 first tim6 or r.plecir|g th€ daedc teirlng

top6 {elagtlc lips6al} at the control gurface geps of aiLur,

.nd horizontal and vortcrl tail.

All ASK 21, Datr Sheet no. L-339, as of scrial no"2I0O1,

optional.

Perlormanca measurements with various gtid€r8 havo Ehown thtt

dtrg cen bs crnsidorably r6&!cod by a continuous fansidon

bstwesi wing ard ell€rofi and b€tweon st blllzor and elevator

respeaively,

This continuous tromition ie achieved by m6ans ot an alasdc

[pseal whic*r i! appliad to tho winE. the stsblllzsr and the

fin rEspadively in otrder to bridge tho actual gap batwaon

wing & aileron, eEblllzer & ol€vator, and fin & rudder, due

to its curvaturs inb whlch it b pre,furmsd to ensura tight

Eoadng on fle coilrol surfaces.

h is import nt to ansrr.€ ftat t'r€ soal undern€efi thie brid*

ing lipssal is 1@ 9( aiftisht, ?ha conuol surfuce gapi ene

sealgd io addition by m6ans of a Tsf,on .soalin0/Blip tap6,

which at tre same tims Bervos to rGduce the trlction of tfie

elastic lipsel on tte ailercn and slev*tc surfaces,

Should the olastic lSpsaal corna off or bs damagad, thls may

l6ad to f,uttBrl

The addhional ailsron, elsvator & ruddof conrol fricdofl g€*-

erated is minlrnal 3nd sccegtebh,

1. lf $s €lastic llpsaal wEs nol fftted bafura to your

glkler, a step muat fkst bs rsbated in tho upp€r winq sur-

face as illua8atad in FIg.l,

IIIOTE:

Ooly tha fhlsh layer is carsfully roilrovad down ae far as

fl. outer FRP lamination without damaging tha glass layor,

Uoocr Wng Surface

StttEt I

2ofE el'lt Zr

MaiirtrBlnsc ln$rucfkt C

lasuc I

Ahrrnd.rGchhichcr

(ffillloq

S.edtpa$(l

O-BftCFoFFrrlrs

Fig.2

2, It tfu Ghsdc lipseal needs to bE r3movad only {or main-

tenanca or topair purposts, Ptoase obs€rYs the following:

For dba$sembly of d*vdor or alsron:

Th6 elaEtiq lipssal and ths ssaling/8lip tgpa m6d to ba

remowd olrlv on thg upo6r surfaca {wlr3 s $e control sur-

facs hlng68 aro locrted).

For disassembly of the ruddcr:

Hero it ls ogt necessary to rornove the elastic lipsoal at

the fin,

2.1 Tha ehstic lipseal must bo rsnovsd very caraldly so as

to svoid any d€lilninadons of fie layers . in thls area. 8*

rnov€ any adhseive regidue bY means of synthadc rssin drin'

oal8.

2.2 Accomplish any r€quired inapsEtion. maint3natlco or repair

work at the conrtd surfsces l}iemselvss and I or their

hing€s.

3. SlYin^ lar ,$a Srd ff rdlacim

iaod lolEstic liosesll

Ilstorr

All surfacas mrst be complately clean, dry snd ft€s from

dust and greassl

This ean best b€ test€d by .ticking a sslf adhssive Hp€

to ths cleaned surfaco and dren pulling lt off again to

crEck t'rat no furthsr du$t particlBs adhsrs to it.

gg.t.-dte-... nejr nlB tis pl.sstc- . Hri.ng upe- qnC.--tg $€dincl

slip tspe ioto agpropriate bngths {refer to the labb ut}'

der poiot "Materiafl.

3.t lr!0!r Wing Surface

Apply 8 12 mm wids t3mporBry pobitioning upe (11 [o.g:

12 mm Tesafilm 1041 abutting the front ed8l3 of the approx,

17 mm wid. rec€Esd s'tep IFis. 21.

.Uooer Wtng Surface

slttsts t:

3af0 A:[( ZI

Main&rffrc. lnrtrucdon C

bsuc I

Ahmnd.rschlolcher

ffi!a

Srg.&Aar&rr

D-eq6hp.rdr*rdt

Flg,3 llnngC WnS Surf.aqp

Now apply rfie sealing/dlp tape {2} l3U Scotch Tsflon Tape

30 mm wldsl sbutting the rear edgp of tha tsmporary gosidon-

ing tepe lll . 86 eareful tirat ths $alirE/sllp taps lkrs

slack ovsr Sro gap,

Set tfte ailgron to meximum iosiriw dgf,sction, so th.t latet

the Teflon s€aling/slip tapo i3 not atrstchod during narmd

full control dsaBcdonsl

Apply full ailgron asvaral timac so thst th3 aea$ng/sllp tap€

fits \llrell into th6 gep.

Then tho Tsflon seelinglslip tape (2! must bo firoly rubbad

down on to the surface.

Then remow the tsmporary positlodng tap6 11, first applied.

P6el the protecdvo backing from tho pl*ric f.irino EBip t3)

lltiylar foil, 30.15mm wide] sod firmly sttuk h on abuttiog dra

frorfi €dge ot th€ raBss6d stBp in rhe wing by ms.ffi ot hs

adhesive lilm layer [FiO.3l.

Press th6 dhesive zonsi of &e plastic fairlng sfrlp firmly

dolvn on ths swfaca using a sofr wooder bloc* l6,E: B8lssl or

i h6rd rubb€r rollar.

Findly, a prut8stive adhe3iv6 t8p€ {4, B applted ovsr dl.

sbutmeot of tlla fronr edgs af tho plestic fei ing $rip {3}

and the $ep in the wing tFn.3l, This tapa ahouH bB as $ln

and moistura.proof as possibla; an oxsmde of a suttabl€ 6p6

would be whhe Tesa lilm No.1O4, 25 mm wide.

This protociivs tepe s€rv6s to prevant th6 d€tachm3fit of frs

frort edg6 of $e p]asth fairing strip {dastic lipseat}

which mlgtrt r€suh in dangeroui f,loht chrrsclarlsdcs,

SHEEt:

4ot6 ,lD al

Mslrt nsnca lnrtrustlon C

lrsur I

Ahrrnds Scfiloaclrsr

dt6

S.g.krnrlat

o-oflgPopp.nh$f,i

3.2 Horizont tail us€r s,urfac€l

There is no racssssd 6tep 3t the gtabilieer' As shown ln Fig.4

tlE sealiog/slip t8p€ l2l I3M Scorch Teflon Tape 3O mm widsl

is stuck o$ ov€r the St bilizet-to'shvstot g8p. At *16 ramo

time fia devstor mu8t bs sBt to maximum ooshive deflecrion,

so $at latsr ths Tsflon sealinglslip tap€ is not strsdled

during nonnal,ull control defl€ctionsl

Be careful thar $€ s€aling/slip tapo ligs slack ovot tl8 gap.

Applv full elsvator sevoral times so *lst th€ saaling/elh

tap€ ffts Yv6ll into tha gap.

Thsa ths Teflon s8aling/slip

down on to $e surfaco. {21 must be firmly rubb3d

Fis.4 Horizont tail uooer surface

Pe6l the prot3stive backing from th€ plasfic strip (3)

lMylar foil, 30.15mm wHel and ffrmly stick h o'l to fi3 stabi'

lizer by rneans of its adhesive film layer [fi9.61.

Prass $€ adha3lv6 zonss of tho plsstic tairisg strip firmlY

_.-.. .{o-wn on t$r- _9!rfgce ueing. a sg.t wsgdlEt-.Qlqc.! le'gr .Balggl- or

a hard rubb€r rollsr,

The zig-zag-tape (5) ls stuck on abutdng the dge of fig

plsstlc fairin! strb l3l.

I*OTE: Tlre ftont tssth lin the directidt of ttu flightl must

not b€ flattencd by pre$ing theflr too far down into ths gke

film, otherwise fnlt artbulator sff€cl wiil bB raducadl

Ho.izoflt tall IpElg surfacc

**'o',r-o.,u,n.

TTTIEE I :eol5A:'t( Zr

irrhton$c. lnrtructlon C

llrur I

Akrnhr8chhlchcr

Oil,lrc6i

${*@r*rt

D-Gl|tPs.,rhfl.st

Fig.6

Fis.7

3.3 Wing and horiuont tail lorvor surfac6:

Removs protec.tive backing from plastk fafuing strip {6,

IMylar foll 22-15 mm widel end stick it oo to th€ wing sod

horhontel .tail lower surfacss, by mGans of hi adhssiw

fflm layor IFig.6:.

Pi€ss tho adhasive zones ol the plssdc lalrlng stlp firrF

ly down oo tho sur[8ce using a soft wooden Hock la.g:

Balsrl, or a hard rubber rullerl

Thsn th€ zio-zag-tape (51 k stuck on ahrtting tho sdge

of tfi6 phstic taidng ctrip (61, [Sse the NOTE urdor

poirlt 3,21.

Wing and horlzont tail b!&I curfece

Thera arc no recs$sd fieps at the lia. As shown ln Hg.7

rhs dastic falrtng $rip (61 lMylar foil, 22-lE mm $,601

is Eluck on over tfie rudder-fin transition at ths l€ft and

rlght sids {with its adhocive film layer on th6 fin}, thsn

pressed firmv down on the Eulfece,

Than .the zig-zao-trp€ {51 iB sfirck on abudng the edge

ot the plastic fairing strip,

3.4 Vertical tdl:

s}IEET:

SofB A5[ e't

M.*ttsn$c. lnstruc{on C

lssuo I

AbEnd.rAchhkllrtr

OrilarOq

SdfEErnbG,

D-Ofi6Popp3*n.o

!&,eI!4

( l laeq,orary BoEltloniag t.tr €

(2)saaUng/slip t.p€

31 6o6tch lfeflon l!!8. 30

tling sur- | colizontll I v€rtlcal

facas I Tail Sfca.a ltall sf,c..3

(3)P1a6tla f.lrkrE t.pe

(4rProtactLve edh€Blve tape

(5)Elg-339 g.P€

(6)Plaatlc faillng tape

Optlond in the dace of {5} aod {61:

( 7)cmbl-8tg-aag/pl.aBttc fatrlng tape I

Iu1.' f^l!- 1B-?n ffi ulda Ilzxl

1r... -l lzxlzt

lr-so -l 1-28 d

' = left 8nd tioht

The materiab r€quirsd c8n bE obained {rom Messrs. Schlehher.

Notes: This action can be 8ccomdiihsd by a compet8nt person.

ln fis ptacs of ths plastic fairing tEp,B 16l and the zig-

-zag-t p3 {5} stomlly a

ins trp€ {71 mry be glued ofl. cornbi-AE-la9/plasdc fair-

3. Ell$rtq that ths elastic_ lig.s€al is in tigftt contact with

$e SurfacEs of thg controls awn when ttsy ars fulV

dsfl*t€d.

The sscure and firm adhesion of the alastic lip must b€

ch€ekd.

Poppenhausen, May 7, 1992 ALEXAI{DEB SCHT"EICHEB

/-cmbH & Go._

W;,5-0 tr6

{Lutz-w, Jumog/

Th6 translation into English has be€n dons by best knowl€dgs end iudgsm€mi in

any casa of doubt the Gennan original is eofltmlling.

ASK 21 Instructions For Continued Airworthness

Navigation menu

Versions of this User Manual:

Views

Navigation