canopy - Schempp-Hirth Flugzeugbau GmbH

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
WARTUNGSHANDBUCH / MAINTENANCE MANUAL
0.1 Erfassung der Berichtigungen / Record of Revisions
Lfd.Nr.
Rev.No.
Benennung
Reference
Seite
Page
Datum
Date
20 Technische Mitteilung Nr. 396-16
Optionale Verwendung der Segelflugzeug-
Rümpfe nach dem
ÄB-Nr. 396-15 (Duo x) oder
ÄB-Nr. 396-16 (Duo xL)
Werk-Nr. 1 bis 533 und 535 bis 541
Technical Note No. 396-16
Optional use of fuselages according to
MB-No. 396-15 (Duo x) or
MB-No. 396-16 (Duo xL)
SN 1 through 533 and 535 through 541
0.2.1
0.2.2
0.2.3
1.1
1.2.3
2.1.2
3.1.2
3.2.2
5.4.1.1
5.4.1.2
6.2.2
6.4.2
6.4.3
6.6.1
6.6.2
6.7
7.1*)
7.2.1*)
7.2.2*)
7.2.3*)
7.2.4*)
7.2.5*)
8.2
8.3*)
8.5
Diagramm 3*)
Diagramm 4
Rep.1
Rep. 2
Rep. 3
Rep. 4
*) nur bei Verwendung
des „xL“-
Rumpfes nach dem
(ÄB-Nr. 396-16)
only use for „xL“
fuselage
(MB-No. 396-16)
Februar
2008
MB: Modification Bulletin – Änderungsblatt
TN: Technical Note – Technische Mitteilung
0.1.5

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
1. Description of components and systems
Further descriptions and assembly are provided on sections 1.4, 1.5, 4.2 and
7 of the Flight Manual.
1.1 Airframe
The “Duo Discus ” is a two-seat sailplane for advanced training and crosscountry
flying, constructed from fiber reinforced plastic (FRP), featuring a
T-tail (with fixed horizontal stabilizer and elevator).
Wing
The wing shells are a glass and carbon fiber/foam-sandwich with spar
flanges made from carbon fiber rovings and shear webs constructed as a
glass fiber/foam-sandwich.
Fuselage
This is a pure carbon fiber (CFRP) lay-up with a aramid fiber reinforcement in
the cockpit area for high energy absorbtion.
Horizontal tailplane
The horizontal tailplane consists of a fixed stabilizer with elevator.
The stabilizer is a GFRP/CFRP/foam-sandwich, the elevator halves are a
pure carbon fiber lay-up.
Vertical tail
Both fin and rudder are constructed as a glass fiber/foam-sandwich.
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-15 (x / xL) 1.1

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
Undercarriage with wheel brake
Steel push-pull tubes connect the u/c operating handles in the cockpit (which
are guided in a gate) to the actuating arm on the rear pivot shaft of the u/c
assembly. A gas strut on the u/c assists in retracting the wheel.
For “wheel up”, the travel of the u/c operating tube in the cockpit is restricted
by the actuating arm resting against the steel tube center frame; for “wheel
down”, the extension stop is the overcentering of the rear u/c struts.
Additionally the travel of the u/c operating tube in the cockpit is restricted by
the gate guiding the front operating handle.
The hydraulic main wheel disc brake is actuated by steel cables (running in a
bowden conduit), connecting the stick mounted brake handles to the wheel
brake master cylinder.
A view of the undercarriage is provided in diagram 4.
Water ballast system(s)
For a description of the water ballast system(s) refer to section 7.9 of the
Flight Manual.
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-15 (x / xL) 1.2.3

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus MAINTENANCE MANUAL
170 mm
[6.69 in.]
TAILPLANE INCIDENCE:
-2.65°
WING INCIDENCE:
1.5°
410 mm [16.14 in.]
176 mm
[6.93 in.]
AILERONS:
Up:
71 ± 5 mm
[2.80 ± 0.20 in.]
Down:
36 ± 5 mm
[1.42 ± 0.20 in.]
WING SWEEPBACK:
Negative sweepback of leading edge
on trapezoidal inboard wing section
228 ± 20 mm
[8.98 ± 0.79 in.]
RIGGING DATA AND
CONTROL SURFACE DEFLECTIONS
February 2008 MB 396-15
Revision 20 TN 396-16 (x) 2.1.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus MAINTENANCE MANUAL
170 mm
[6.69 in.]
TAILPLANE INCIDENCE:
-2.65°
WING INCIDENCE:
1.5°
410 mm [16.14 in.]
176 mm
[6.93 in.]
AILERONS:
Up:
71 ± 5 mm
[2.80 ± 0.20 in.]
Down:
36 ± 5 mm
[1.42 ± 0.20 in.]
WING SWEEPBACK:
Negative sweepback of leading edge
on trapezoidal inboard wing section
228 ± 20 mm
[8.98 ± 0.79 in.]
RIGGING DATA AND
CONTROL SURFACE DEFLECTIONS
February 2008 TN 396-12 / MB 396-15
Revision 20 TN 396-16 (x) 2.1.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
• Tow release mechanism(s)
Checks should be carried out in accordance with the
“Operating & Maintenance Instructions for the TOST tow Release Mechanism(s)”
- see also section 9 “Service Instructions”.
• Instruments
In the case of all installed instruments and equipment, the instructions of
the relevant manufacturer should be followed.
• Safety harness
At present the service time of the webbing on the restraint systems
available is limited to twelve (12) years including the time of storage.
See also the service instructions provided by the relevant manufacturer.
• Gas strut
A tension gas strut is attached to the U/C.
The rod of the gas strut must always be perfectly clean and must not be
damaged in any way whatsoever.
If oil has escaped through the seal, the gas strut must be replaced.
February 2008
Revision 20 TN-No. 396-16 (x / xL) 3.1.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
After cleaning the entire aircraft, the following checks should be made:
• Check the aircraft externally for damage such as cracks, holes, scratches,
buckling and delamination.
If the outer layer(s) of a component, constructed as a sandwich, has been
damaged, then the inner skin must be checked as well.
It is recommended to call upon expert assistance.
• All fittings which are mounted on GFRP (CFRP) structures must be
checked to confirm there has been no movement.
Check also the CFRP (GFRP) structure at the fittings for cracks, white
spots and delamination.
• Check all accessible metal parts for damage.
It is generally found, however, that if the aircraft is operated correctly, no
damage will have occured.
If repairs are necessary, then the manufacturer’s recommendations
should be followed.
• Check all accessible metal parts such as fittings, control rods (push/pull
tubes) and actuating levers for corrosion.
If necessary, remove the rust, clean thoroughly and apply a fresh corrosion
protection.
The special primer and paint for this surface protection may be obtained
from Schempp-Hirth Flugzeugbau GmbH.
• Linkage for attaching and locking the canopy
Check linkage attaching/detaching and locking/opening the canopy for
any damage.
Check guides for locking rod on canopy frame, locating pins on fuselage
and front GFRP hinge for delamination/cracks. Check rear metal hinge for
deformation.
February 2008
Revision 20 TN-No. 396-16 (x / xL) 3.2.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
5.4 Main wheel with hydraulic disc brake
Main wheel TOST:
When removing the main wheel to clean and grease it, first remove the two
bolts attaching the brake back plate to the brake cylinder, then remove brake
calliper (hydraulic pressure hose remains attached).
Disassemble the attachment bolt of the brake shield on the inner side of the
swinging arm.
Next remove cotter pin and castle nut from one side of the wheel axle and
withdraw the latter. Take out spacer on the ride side of the wheel and remove
the wheel (take care that no washers, spacers or bushings get lost).
Prior to re-assembly, clean all parts and lubricate bearings, bushings and the
axle.
Observe the instructions provided by the supplier of the wheel,
TOST company, Munich, Germany
Main wheel BERINGER
Observe the instructions provided by the supplier of the wheel,
BERINGER company, Chǎtelneuf, France.
NOTE: Do not disconnect the hydraulic pressure hose from the brake
cylinder and do not actuate the wheel brake while brake calliper is
removed from the brake disc.
The hydraulic wheel brake may be actuated by the handle provided at the
control sticks.
Front wheel-brake:
The Bowden cable is directly connected with the actuating segment of the
brake master cylinder.
Rear wheel-brake:
The Bowden cable is connected to the attachment of the brake master
cylinder. The tube of the Bowden cable fits to the actuating segment of the
brake master cylinder and actuates the actuating segment when the rear
wheel brake is applied.
Whenever a reduced effectiveness of the wheel brake is observed,
see page 5.4.1.2.
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-16 (x / xL) 5.4.1.1

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
In case of reduced effectiveness of the wheel brake
1. Check brake pads:
If the thickness of the brake pads is less then 1.5 to 2mm replace brake pads.
Therefore both parts of the brake calliper have to be removed.
2. Check leak tightness of the hydraulic-system.
3. Check brake fluid:
a) Remove front seat pan
b) Remove cover of brake fluid-container
c) If necessary refill missing brake fluid and bleed the braking system as
described on page 5.4.2
d) Check effectiveness of the wheel brake. Afterwards reassemble the
disassembled parts
4. Readjustment of the Bowden cables:
Note:
a) The Bowden cables may be readjusted at the adjustment
point at the control stick until the gap between the
actuating segment on the brake master cylinder and the
cylinder case is about 1.0 mm (0.04 in). To do this the
wheel brake has to be relieved.
To check the readjustment pull the brake handle several
times. With relieved wheel brake:
i) the wheel can still be rotated by hand
ii)
it has still to be possible to push the brake
calliper back in direction to the wheel by hand
b) Check the function of the wheel brake after assembling
the seat pan
Normally the brake system has to be bleeded, if the fuselage is stored inverted!
If the brake handle is fixed in pulled position during the inverted storage of the
fuselage, the bleeding of the brake system usually is not necessary
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-16 (x / xL) 5.4.1.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
Datum plane:
Aircraft attitude:
Wing leading edge at root rib
Tail jacked up such that a wedge-shaped
block, 100 : 4.5, placed on the rear top
fuselage, is horizontal along its upper
edge.
Distance main wheel: a = 8 mm (0.31 in.)
Distance tail wheel:
Distance skid:
b = 5322 mm (209.53 in.)
b = 5357 mm (210.91 in.)
Empty mass c/g position:
x =
W 2
x b
W
+ a
C/G position in flight:
(just given for the case that the “c/g position in flight” is to be determined by
weighing rather than by computing it on the basis of the empty mass c/g position)
The aircraft is to be weighed fully equipped (crew with parachutes and
complete outfit incl. barograph, cushions, cameras etc.) Seat back and rudder
pedals should be correctly adjusted for this purpose.
x =
W 2 loaded
x b
W empty
+ W disposable
+ a
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-16 (x / xL) 6.2.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
Forward c/g limits: With a maximum seat load of 110 kg (242.5 lb)
on either seat and with maximum permitted water
ballast
Rearward c/g limits: With various minimum loads on the front seat
(allowance for 5.0 kg / 11.02 lb baggage already
made)
To facilitate the checking of the empty mass center of gravity, the table
below shows – at different empty mass values – the maximum permissible
load on the tail wheel, with various loads on the front seat and in
relation to the most rearward c/g position.
The actual load on the tail wheel is determined with the aircraft in
weighing attitude, i.e. main wheel on the ground and tail jacked up as
described on page 6.2.1.
If the load on the tail wheel does not exceed the corresponding value in
the table, the center of gravity is within the permitted range.
Empty mass
Load on tail wheel (or skid) with a minimum seat load of:
70 154 75 165 80 176 85 187 90 198
kg lb kg lb kg lb kg lb kg lb kg lb
410 904 39.7 87.5 41.2 90.8 42.8 94.4 44.3 97.7 45.9 101.2
420 926 40.1 88.4 41.7 91.9 43.2 95.3 44.8 98.8 46.3 102.1
430 948 40.6 89.5 42.1 92.8 43.7 96.4 45.2 99.7 46.8 103.2
440 970 41.1 90.6 42.6 93.9 44.2 97.5 45.7 100.8 47.3 104.3
450 992 41.5 91.5 43.1 95.0 44.6 98.3 46.2 101.9 47.7 105.2
460 1014 42.0 92.6 43.5 95.9 45.1 99.4 46.6 102.8 48.2 106.3
470 1036 42.4 93.5 44.0 97.0 45.5 100.3 47.1 103.9 48.6 107.2
480 1058 42.9 94.6 44.4 97.9 46.0 101.4 47.5 104.7 49.1 108.3
490 1080 43.3 95.5 44.9 99.0 46.4 102.3 48.0 105.8 49.5 109.1
500 1103 43.8 96.6 45.3 99.9 46.9 103.4 48.4 106.7 50.0 110.3
Note:
Should a tail skid be fitted (instead of a tail wheel), the above values are
to be multiplied by a factor of 0.993).
February 2008 MB-No. 396-15
Revision 20 TN-No. 396-16 (x) 6.4.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
Empty mass c/g range
in. mm
23.62 600
23.23 590
22.83 580
22.44 570
22.05 560
21.65 550
21.26 540
20.87 530
20.47 520
90kg
198lb
85kg
187lb
20.08 510
19.69 500
19.29 490
18.90 480
18.50 470
80kg
176lb
75kg
165lb
70kg
154lb
18.11 460
17.72 450
17.32 440
FOREMOST EMPTY
MASS C/G POS.
16.93 430
EMPTY MASS (kg / lb)
500
1103
kg
lb
February 2008 MB-No. 396-15
Revision 20 TN-No. 396-16 (x) 6.4.3

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
6.6 Useful load
Load on the seats
a) Water ballast fin tank not installed
Note:
(*) Depending on its equipment and the installation of fixed trim ballast, the actual
minimum and/or maximum seat loads of this “Duo Discus” (to which this manual
refers) may differ from the above typical weights.
The placards in the cockpit must always show the actual weights, which are also
to be entered in the log chart – see flight manual, page 6.2.3.
Neither the maximum permitted all-up mass nor the maximum mass of the non-lifting
parts must be exceeded.
Determination of the maximum permitted load on the seats:
Flown solo:
Two occupants:
SEAT
LOAD
front
seat load
rear
seat load
LOAD ON THE SEATS
(crew incl. parachutes)
TWO PERSONS
min. max.
70* kg
154* lb
at choice
Maximum cockpit seatload
110* kg
243* lb
110* kg
243* lb
Always 110 kg (242.5 lb)
ONE PERSON
min. max.
70* kg
154* lb
110* kg
243* lb
Maximum cockpit load (load on both seats) may not be
exceeded. For seat loads below the placarded minimum
refer to Flight manual - section 6.2
The total of the loads on front and rear seat has to be lower
than the maximum cockpit seatload.
At the same time pay attention, that the load on each seat
stays below 110 kg (242.5 lb)
Maximum seat load: This is the difference between the maximum permitted mass of
the non-lifting parts (440 kg / 970 lb) and their actual mass
(refer to last weighing report).
b) Water ballast fin tank installed
Note:
SEAT
LOAD
front
seat load
rear
seat load
LOAD ON THE SEATS
(crew incl. parachutes)
TWO PERSONS
min. max.
100 **
220 kg 100 **
*
** lb 110*
243* kg 220 *
kg
** lb
( 70* kg)
lb ( 70* kg)
(154* lb)
(154* lb)
110*
at choice
243* kg
lb
Maximum cockpit seatload
ONE PERSON
min. max.
110*
243* kg
lb
Maximum cockpit load (load on both seats) may not be
exceeded. For seat loads below the placarded minimum refer
to Flight manual - section 6.2. The value shown in parenthesis
may be used after having thoroughly checked the ballast
quantity in the fin tank and the appropriate loading chart.
(*) Depending on its equipment and the installation of fixed trim ballast, the actual
minimum and/or maximum seat loads of this “Duo Discus” (to which this manual
refers) may differ from the above typical weights.
If so, the log charts and the placards must be altered accordingly.
(**) 1. For safety reasons the minimum seat load for flights with empty fin tank must
be increased by 30 kg (66 lb) so as to allow for an unnoticed filled fin tank.
2. Adding the mass of 30 kg (66 lb) is not required, however, if the pilot either
- dumps all water ballast (prior to take off)
or
- determines the ballast quantity in the fin tank and ensures that it is
compensated by an appropriate load in the wing tanks and/or on the
aft seat.
The placards in the cockpit must always show the actual weights (including those
allowing for a filled fin tank **), which are also to be entered in the log chart – see
flight manual, page 6.2.3.
Neither the maximum permitted all-up mass nor the maximum mass of the non-lifting
parts must be exceeded.
February 2008 MB-No. 396-15 / TN-No. 396-13
Revision 20 TN-No. 396-16 (x)
6.6.1

Duo Discus
SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
MAINTENANCE MANUAL
For establishing a "Weight & Balance Report" the following lever arms
are to be used:
Trim ballast under front instrument
panel
Trim ballast on right hand side of
front control stick mounting frame
Pilot, front seat (with parachute or
back cushion)
Pilot, rear seat (with parachute or
back cushion)
Battery at rear control stick
mounting frame
Center of gravity of:
2055 mm forward of datum
80.91 in.
1855 mm forward of datum
73.03 in.
1400 mm forward of datum
55.12 in.
290 mm forward of datum
11.42 in.
680 mm forward of datum
26.77 in.
Main wheel 8 mm aft of datum
0.31 in
Waterballast, wings 65 mm aft of datum
2.56 in.
Tail wheel 5330 mm aft of datum
209.84 in.
Tail skid 5365 mm aft of datum
211.22 in.
Water ballast, fin 5320 mm aft of datum
209.45 in.
Baggage 1000 mm aft of datum
39.37 in.
February 2008 MB-No. 396-15
Revision 20 TN-No. 396-16
6.6.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
6.7 Mass – C/G diagram
lb
kg
1543 700
MAXIMUM ALL-UP MASS
1433 650
ALL - UP MASS (kg / lb)
1378 625
1323 600
1257 570
1213 550
1135 515
FORE MOST C/G POSITION
PERMITTED
RANGE
REARMOST C/G POSITION
1102 500
1038 471
mm
in.
X (mm / in.) aft of datum
in flight
February 2008 MB 396-15
Revision 20 TN 396-16 (x) 6.7

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
MAINTENANCE MANUAL
without fin tank
LOAD ON THE SEATS
(crew incl. parachutes)
SEAT LOAD TWO PERSONS ONE PERSON
min. max. min. max.
front
seat load
rear
seat load
70* kg
154* lb
at
choice
110* kg
243* lb
110* kg
243* lb
70* kg
154* lb
110* kg
243* lb
Maximum cockpit seat load 220* kg / 485* lb
Maximum cockpit load (load on both seats) may not
be exceeded. For seat loads below the placarded
minimum refer to Flight manual - section 6.2.
(if installed)
fin tank installed
LOAD ON THE SEATS
(crew incl. parachutes)
SEAT LOAD TWO PERSONS ONE PERSON
min. max. min. max.
100* kg
100* kg
front 220* lb 110* kg 220* lb 110* kg
seat load ( 70* kg) 243* lb ( 70* kg) 243* lb
(154* lb)
(154* lb)
rear
seat load
at
choice
110* kg
243* lb
Maximum cockpit seat load 220* kg / 485* lb
Maximum cockpit load (load on both seats) may not
be exceeded. For seat loads below the placarded
minimum refer to Flight manual - section 6.2.
The value shown in parenthesis may be used after
having thoroughly checked the ballast quantity in the
fin tank and the appropriate loading chart.
Placing:
Cockpit inner skin on
the right for either seat
WHEN FLOWN SOLO, THE PLACARDED
MINIMUM FRONT SEAT LOAD MAY BE
REDUCED BY UP TO:
NUMBER OF LEAD
PLATES REQUIRED
- 05 kg (11 lb) 1
- 10 kg (22 lb) 2
- 15 kg (33 lb) 3
Cockpit inner skin on the right
(front seat only)
- 20 kg (44 lb) 4
- 25 kg (55 lb) 5
- 30 kg (66 lb) 6
LOCKING PIN FLUSH
WITH UPPER SURFACE
Locking device for outbd. wing panels
Outbd. end of main wing panels
February 2008 MB-No. 396-15 / TN-No. 396-13
Revision 20 TN-No. 396-16 (x) 8.2

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus MAINTENANCE MANUAL
Placing:
Locking of canopy
On red locking lever on the left,
provided for either seat
(if installed)
Ballast in fin tank is dumped
simultaneously with wing tanks
Operating knob for dumping
ballast from wing tanks
Front seat above guide slot for operating
knob on cockpit inner skin on the right
Air quantity
Next to operating knob protruding
from front instrument panel
push
pull
Airstream direction
Next to operating knob protruding
from front instrument panel
C A N O P Y
attachment / detachment
Canopy
attachment/detachment
Above operating handle on
cockpit inner skin on the right
for either seat
February 2008 MB 396-15
Revision 20 TN 396-16 (x) 8.5

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus T MAINTENANCE MANUAL
UNDERCARRIAGE WITH RETRACTING LINKAGE
AND HYDRAULIC DISC BRAKE
1. Front retracting linkage
2. Rear retracting linkage
3. Brake handle on front control stick
4. Brake handle on rear control stick
5. Brake master cylinder with reservoir
February 2008 MB 396-15
Revision 20 TN 396-16 (x) DIAGRAM 4

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
REPAIR INSTRUCTIONS
REPAIR INSTRUCTIONS FOR „Duo Discus “
The components of this aircraft are constructed as follows:
1. Inboard wing panels
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 8 mm (0.31 in.)
Wing tip extension
GFRP/foam-sandwich,
with HEREX C 70.55,
thickness 6 mm (0.24 in.)
2. Ailerons
Inboard: GFRP/foam-sandwich, with HEREX C 70.55,
thickness 4 mm (0.16 in.)
Outboard:
Pure GFRP/CFRP-shell
3. Fuselage
Forward section: Pure CFRP/Kevlar/GFRP-shell
Aft section:
Pure CFRP-shell
4. Fin
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 6 mm (0.24 in.)
5. Rudder
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 4 mm (0.16 in.)
6. Horizontal stabilizer
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 6 mm (0.24 in.)
7. Elevator halves
Pure CFRP-shell
February 2008
Revision 20 TN-No. 396-16 (x + xL) - 1 -

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
REPAIR INSTRUCTIONS
REPAIR INSTRUCTIONS FOR „Duo Discus “
The components of this aircraft are constructed as follows:
1. Inboard wing panels
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 8 mm (0.31 in.)
Wing tip extension
GFRP/foam-sandwich,
with HEREX C 70.55,
thickness 6 mm (0.24 in.)
with winglets
Pure GFRP/CFRP-shell
2. Ailerons
Inboard: GFRP/foam-sandwich, with HEREX C 70.55,
thickness 4 mm (0.16 in.)
Outboard:
Pure GFRP/CFRP-shell
3. Fuselage
Forward section: Pure CFRP/Kevlar/GFRP-shell
Aft section:
Pure CFRP-shell
4. Fin
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 6 mm (0.24 in.)
5. Rudder
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 4 mm (0.16 in.)
6. Horizontal stabilizer
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 6 mm (0.24 in.)
7. Elevator halves
Pure CFRP-shell
February 2008 TN-No. 396-12
Revision 20 TN-No. 396-16 (x + xL) - 1 -

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
REPAIR INSTRUCTIONS
REPAIR INSTRUCTIONS FOR „Duo Discus “
The components of this aircraft are constructed as follows:
1. Inboard wing panels
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 8 mm (0.31 in.)
Wing tip extension
GFRP/foam-sandwich,
with HEREX C 70.55,
thickness 6 mm (0.24 in.)
with winglets
Pure GFRP/CFRP-shell
2.a Ailerons
Inboard: GFRP/foam-sandwich, with HEREX C 70.55,
thickness 4 mm (0.16 in.)
Outboard:
Pure GFRP/CFRP-shell
2.b Trailing edge flap
GFRP/foam-sandwich,
with HEREX C 70.55,
thickness 4 mm (0.16 in.)
3. Fuselage
Forward section: Pure CFRP/Kevlar/GFRP-shell
Aft section:
Pure CFRP-shell
4. Fin
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 6 mm (0.24 in.)
5. Rudder
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 4 mm (0.16 in.)
6. Horizontal stabilizer
GFRP/foam-sandwich, with HEREX C 70.55,
thickness 6 mm (0.24 in.)
7. Elevator halves
Pure CFRP-shell
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-16 (x / xL) - 1 -

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
REPAIR INSTRUCTIONS
The first stage in carrying out repairs on components constructed from fiber reinforced
plastic (FRP) is to examine the construction of the component at the location
in question and to proceed in accordance with the latest applicable issue of
the
„REPAIR INSTRUCTIONS FOR SCHEMPP-HIRTH SAILPLANES
AND POWERED SAILPLANES CONSTRUCTED FROM FIBER
REINFORCED PLASTIC“
General considerations
For repairs only the following resin systems must be used:
1. For GFRP-components
Resin Hardener Mixing proportion
by weight
L 285 286 or 287 100 : 38
LY 5052 HY 5052 100 : 38
L 335 335 or 340 100 : 38
Curing : 15 hours at 50° C (122° F)
2. For CFRP/AFRP components
Resin Hardener Mixing proportion
by weight
L 285 286 or 287 100 : 38
LY 5052 HY 5052 100 : 38
L 335 335 or 340 100 : 38
Curing : 15 hours at 55° C (131° F)
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-16 (x / xL) - 2 -

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
REPAIR INSTRUCTIONS
MATERIALS (AND SUPPLIERS) FOR THE REPAIR OF CFRP-COMPONENTS
Resin system: See page 2
Carbon fiber cloth:
(Yarn DIN 65184 CC 200 f 3000-F)
Cloth 1/1 (warp equal weft)
a) Weight 200 g/m²: e.g. Quality 98140 or 98141 from CS-Interglas AG, Ulm
Sigratex KDL 8003 from SGL Carbon Group, Meitingen
Style 450 from C. Cramer & Co., Heek-Nienborg
b) Weight 285 g/m²: e.g. Quality 98160 from CS-Interglas AG, Ulm
Style 475T from C. Cramer & Co., Heek-Nienborg
Unidirectional
carbon fiber cloth:
Weight 140 g/m²
(carbon fiber 120 g/m², glass fiber 20 g/m²), quality
e.g. Style 763 from C. Cramer & Co., Heek-Nienborg or
MDL 9001 from SGL Carbon Group, Meitingen
Carbon fiber tape: (Yarn DIN 65184)
e.g. Quality Sigratex KDU/NF6, 39-7.5
Sigratex KDU -1001, width: 75 mm (2.95 in.)
from SGL Carbon Group, Meitingen
Carbon fiber / Aramid
fiber (Kevlar) cloth: CF: Yarn DIN 65184 CC 200 f 3000-F
AF: Yarn DIN 65427
Linen cloth 1/1 (warp equals weft), weight 205 g/m²
e.g. Quality 98355 from CS-Interglas AG, Ulm
Carbon fiber rovings:
(Yarn DIN 65184 CC 800 f 12000-F)
e.g. Quality Tenax HTA 5131 800tex f 12000to
from Tenax-Fibers, Wuppertal
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-16 (x / xL) - 3 -

SCHEMPP-HIRTH FLUGZEUGBAU GmbH., KIRCHHEIM/TECK
Duo Discus
REPAIR INSTRUCTIONS
Surface coating: ● UP-Vorgelat, white, No. T 35
● UP-Hardener No. SF 10
● UP-Thinner No. SF
from Scheufler, Stuttgart
Mixing proportion by weight:
100 parts UP-Vorgelat T 35 to 10 parts hardener SF 10
February 2008 MB-No. 396-15 resp. MB-No. 396-16
Revision 20 TN-No. 396-16 (x / xL) - 4 -