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DG Flugzeugbau GmbH

Flight Manual LS 8-18 Emergency

Procedures

3.7.8 Emergency Landing on Water

During a water landing test with landing gear retracted, the sailplane used submarined completely.
As submarining may be possible also with gear extended, the following procedure is
recommended:

(a)

in downwind leg of your landing pattern

(1)

extend landing gear

(2)

open parachute harness

(b)

Touch down with gear extended and speed as low as possible.

(c)

At touch-down point use left arm to protect face against possible canopy fracture.

(d)

After touch down undo parachute and seat belt harnesses.

(e)

Leaving the cockpit under water, when the canopy has not fractured, is perhaps possible only
after the forward fuselage is almost completely full of water.

3.7.9 Flight in the Vicinity of Thunder Storms

Due to lightning flash, carbon fibre structures have been destroyed again and again. Therefore,
flights and especially winch launches

in the vicinity of thunder storms

should be avoided, as in

important structures of the LS8-18 carbon fibres are used.

Edition: July 1999

LBA-appr. Revision - 0

Page 3-6

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Summary of Contents for LS 8-18

Page 1: ...is sailplane is to be operated in compliance with information and limitations contained herein In order that the manufacturer can continue to provide essential service information any change of ownership should be notified to the manufacturer immediately The translation of this manual has received our most careful attention However in any case of doubt or ambiguity the original German text must be...

Page 2: ...nd margin and the revision No and the date will be shown on the bottom left hand of the page Rev No Pages affected Description Date LBA Approval 1 0 2 0 3 1 1 2 3 2 4 2 5 2 6 2 8 3 4 4 2 4 3 4 4 4 5 4 8 4 9 4 12 5 3 6 1 6 2 8 3 TN8011 removal of tail fin battery may be used for trimming Dec 2001 25 01 2002 Rev No Pages affected Description Date EASA Approval 2 0 2 0 3 4 7 4 13 4 14 7 2 TN8019 whee...

Page 3: ...3 Dec 2001 2 4 Dec 2001 2 5 Dec 2001 7 7 1 July 1999 2 6 Dec 2001 7 2 February 2011 2 7 July 1999 7 3 July 1999 2 8 Dec 2001 7 4 July 1999 7 5 July 1999 7 6 July 1999 3 3 1 July 1999 3 2 July 1999 3 3 July 1999 8 8 1 July 1999 3 4 Dec 2001 8 2 July 1999 3 5 July 1999 8 3 Dec 2001 3 6 July 1999 8 4 July 1999 8 5 July 1999 8 6 July 1999 4 4 1 July 1999 4 2 Dec 2001 4 3 September 2011 9 9 1 July 1999...

Page 4: ...on approved 2 Limitations approved 3 Emergency Procedures approved 4 Normal Procedures approved 5 Performance partly approved 6 Weight and Balance non approved 7 Description of Systems non approved 8 Handling Servicing and Maintenance non approved 9 Supplements non approved Edition July 1999 Revision 0 Page 0 4 ...

Page 5: ... Basis This type of sailplane has been approved by Luftfahrt Bundesamt LBA Braunschweig in accordance with JAR 22 dated 28 October 1985 Change 5 with the exemption of JAR 22 49 b 2 ii stalling speed with air brakes extended at maximum all up weight for the 15 m version The LBA Type Certificate No 402 for LS 8 18 was issued on 20 Jan 2000 Category of Airworthiness Utility This Flight Manual constit...

Page 6: ...duced using the latest technology of industrial fibre design Glass Aramid and Carbon fibres It is designed for competition flights high performance combined with excellent handling characteristics Wing span 15m 49 21ft 18m 59 6ft Length 6 66m 21 84ft 6 66m 21 84ft Height 1 33m 4 36ft 1 33m 4 36ft MAC 0 700m 2 3ft 0 634m 2 08ft Wing area 10 5 m 113 0sq ft 11 4 m 122 9sq ft Wing aspect ratio 21 43 2...

Page 7: ...tems and standard equipment The limitations included in this section and in section 9 have been approved by LBA Luftfahrt Bundesamt Braunschweig The LS 8 18 sailplane has been designed and approved according to JAR 22 requirements Factors of safety relation of ultimate loads to permissible maximum loads occurring during operation are 1 5 only Thus ultimate loads will be reached when exceeding perm...

Page 8: ...ot exceed this speed except in calm air and then only with caution Examples of rough air are lee wave rotor thunderclouds dust devils and turbulence when crossing mountain ridges in strong winds VA Manoeuvring speed 190 103 118 Do not make full or abrupt control movement above this speed because under certain conditions the sailplane may be overstressed by full control movement VW Maximum winch la...

Page 9: ...d line 280 km h 151 Kt 174 mph Maximum speed for all not restricted operations Yellow 90 km h triangle 49 Kt 56 mph Recommended minimum approach speed at maximum weight without water ballast For an example of airspeed indicator colour marking see below Airspeed Indicator diameter 80 mm 3 15 in This type of marking is not possible with 57 mm 2 24 in diameter green yellow red red altitude related VN...

Page 10: ...y installed instruments canopy and main pins Cockpit load Pilot parachute equipment for instance tail fin battery in baggage compartment Horizontal tail Water ballast and battery in tail fin do not count for non lifting parts but for maximum all up weight Wing water ballast depending on loading conditions max 190 kg 419 lbs Warning Wing water ballast must always be compensated by tail fin water ba...

Page 11: ... compensate C G displacement due to wing water ballast surplus may be used to compensate pilot weight above Minimum Cockpit Load Maximum amounts see pages 4 11 12 2 6 Approved manoeuvres Category of Airworthiness The LS 8 18 sailplane is certified in the U Utility category according to JAR 22 Aerobatic flight not approved 2 7 Manoeuvring load factors At 190 km h 103Kt 118 mph 5 3 g positive to 2 6...

Page 12: ...ckpit load Pilot plus parachute no baggage no temporary equipment See entry on page 6 1 2 for club use and normally without tail tank no trim ballast 70 kg 154 lbs with 3 trim weights 55 kg 121 lbs 1 Trim weight 2 5kg 5 5lbs corresponds to 5 kg 11 lbs of Cockpit load If the sailplane does not fly in a club it may be trimmed for a higher minimum cockpit load See instructions in Maintenance Manual c...

Page 13: ...d Operating placards Flight Manual LS8 18 Additionally for cloud flying Airspeed Indicator recommended scale 50 300 km h with 1 turn only 27 162 Kt 30 186 mph Turn and bank indicator Compass compensated in sailplane Variometer recommended range at least 10 m s 2000 ft min 20 Kt 2 11 Aero tow Winch launch and Auto tow Maximum approved winch launch speed 140 km h 76 Kt 87 mph also valid for Auto tow...

Page 14: ...t Load min ______kg lbs Up to 2000 6500 280 174 151 Minimum Cockpit Load with Up to 3000 9800 266 165 144 empty tail tank Up to 4000 13100 253 157 137 and without tail battery min ______kg lbs Up to 6000 19700 227 141 122 Minimum Cockpit Loads for all combinations Up to 8000 26200 202 126 109 of tail tank and tail battery see Flight Manual Up to 10000 32800 179 111 97 pages 6 1 2 Up to 12000 39400...

Page 15: ...Section 3 provides checklist and amplified procedures for coping with emergencies that may occur Emergencies caused by sailplane malfunction are extremely rare if proper pre flight inspections and maintenance are practised However should an emergency arise the basic guidelines described in this section should be considered and applies as necessary to correct the problem 3 2 Emergency Canopy Jettis...

Page 16: ...s considerably Termination Stick forward to neutral Stalling speed at maximum weight 525 kg 1157 lbs straight flight and air brakes retracted 83 km h 45 Kt 52 mph with 15 m 49 ft wingspan 80 km h 43 Kt 50 mph with 18 m 59 ft wingspan air brakes extended 87 km h 47 Kt 54 mph with 15 m 49 ft wingspan 85 km h 46 Kt 53 mph with 18 m 59 ft wingspan When during stalled flight the angle of incidence is i...

Page 17: ...m 300 ft Note According to actual aileron deflection and C G position more or less pronounced floating around the pitch axis occurs during spinning 3 6 Spiral Dive Recovery Spiral dive may occur when the sailplane terminates spinning on its own and not by pilots action Then Rudder opposite to dive rotation Aileron opposite to angle of bank Elevator pull cautiously Warning During dive out be alert ...

Page 18: ...d during descent in rough air wave flights a speed of 190 km h 103 Kt 118 mph green ASI range upper limit should not be exceeded because of possible severe turbulence 3 7 2 Rain During Rain a expect considerable decrease of performance b increase approach to landing speed by at least 10 km h 5 Kt 6 mph above normal approach speed because 1 stall speed increases 2 effectivity of controls decreases ...

Page 19: ...diately and land in front of winch Caution Water ballast discharge is recommended before each landing Landing with maximum all up weight is not recommended In this case at least 25 Litres 6 6 US gallons 5 5 UK gallons corresponding to 15 seconds of discharge time should be dumped prior to landing 3 7 6 Emergency Landing with Landing Gear Retracted Emergency landings with landing gear retracted are...

Page 20: ... c At touch down point use left arm to protect face against possible canopy fracture d After touch down undo parachute and seat belt harnesses e Leaving the cockpit under water when the canopy has not fractured is perhaps possible only after the forward fuselage is almost completely full of water 3 7 9 Flight in the Vicinity of Thunder Storms Due to lightning flash carbon fibre structures have bee...

Page 21: ... 5 10 1 Vertical Tail Fin Tank Loading Procedure 4 9 4 5 10 2 Wing Tank Loading Procedure 4 10 4 5 10 3 Loading Plan for Water Ballast 4 10 4 5 10 4 Maximum Wing Water Ballast Table 4 11 4 5 10 5 Maximum Tail Fin Water Ballast Table 4 12 4 5 10 6 Dumping of Water Ballast 4 13 4 5 11 Winch Launch Auto Tow 4 13 4 5 12 Aero tow 4 14 4 5 13 Free Flight 4 14 4 5 14 High Altitude Flight 4 15 4 5 15 Side...

Page 22: ...ely when bushings are lined up correctly 9 Secure main pins by placing handles behind spring loaded pegs 10 Insert battery into that place which was defined during last C G weighing and calculation of cockpit load ranges see Data Placard in cockpit or entry on page 6 1 2 Connect to system and check operation The battery must be equipped with an appropriate main fuse 11 Check forward horizontal tai...

Page 23: ...g With wings positioned vertical in trailers with hinged cover the air brakes may open and be damaged when closing the lid Note To avoid damage due to water after de rigging the water drain plug at the root rib forward edge should be removed and discharge openings on wing under side kept open for ventilation use valve opener 4 3 Daily Inspection The Daily Inspection according to the following diag...

Page 24: ...re marks cracks b Total energy port at upper end of vertical tail fin leading edge free from clogging c Pitot pressure port below total energy port at vertical tail fin leading edge free from clogging d Charged vertical tail fin battery connected when this battery location was chosen for trimming of pilot weight see entries on page 6 1 2 e Check vertical tail tank valve for proper opening place ta...

Page 25: ...ment panel for function indication of surrounding air temperature g Check for non existence of foreign matter Warning When parking remember that under a certain sun angle from the rear into the opened canopy this may result in fire hazard due to convex lens effect 4 4 Pre flight Check 1 Daily inspection performed 2 Control system functions checked using a helper 3 Vertical tail fin tank valve open...

Page 26: ...ons 8 Check tail dolly removed 9 Fasten seat belt harness 10 Connect parachute static line 11 Lock air brakes 12 Check trim position 13 Check release system 14 Lock canopy 4 5 2 Adjustment of Rudder Pedals a Possible in flight or on the ground b Release pressure on pedals and unlock pawl by pulling black pedal handle c Forward adjustment 1 push pedals forward with feet 2 lock into desired position...

Page 27: ...rsonal adjustment Warning Moving aileron with stick fully back the stick must not open the safety harness Warning When the backrest is removed for huge pilots then 1 the guide tube must also be removed it may obstruct an emergency exit 2 Additionally an adjustable headrest according to drawing 3BR 101 must be installed 4 5 5 Retractable Landing Gear a Extension or retraction permitted over whole a...

Page 28: ... with insufficient weight 3 trim weights can be fitted to a threaded rod in front of rudder pedals and secured by knurled nut 1 trim weight of 2 45 kg 5 5 lbs compensates 5 kg 11 lbs of pilot weight When removing the tail fin battery Standard weight 2 5 to 2 7 kg 5 5 to 6 lbs Minimum Cockpit Load decreases by 10 kg 22 lbs see page 6 1 2 Balancing of heavy pilots who want to fly with rearward C G p...

Page 29: ...ward b Insert tail fin tank adapter to filling funnel tube and connect to dumping outlet just inside lower right rudder cut out with rudder deflected to the left c Fill tail fin tank via funnel in relation to intended wing water amount see table page 4 12 d Markings correspond to 0 5 Litres 0 13 US gallons 0 11 Imp gallons steps equivalent to 0 5 kg 1 1 lbs e Use water level in funnel tube relativ...

Page 30: ...roper valve sealing and avoid clogging of overflow pipes and draining orifices i Fill the other wing as outlined above Warning When amount of water ballast in wings is not equal this may favour ground loop tendencies during take off j After filling ballast and before take off the following must be checked 1 Not even minor leaks at wing system allowed 2 Tail tank valve opens simultaneously with or ...

Page 31: ... 139 135 130 125 120 110 159 154 149 144 139 135 130 125 120 115 Cockpit Load Pilot Empty Mass parachute equipment lbs lbs 551 562 573 584 595 606 617 628 639 650 154 419 419 412 403 392 381 370 359 351 340 165 419 412 403 392 381 370 359 351 340 328 176 412 403 392 381 370 359 351 340 328 317 187 403 392 381 370 359 351 340 328 317 306 198 392 381 370 359 351 340 328 317 306 298 209 381 370 359 3...

Page 32: ... see 162 5 174 5 6 5 169 181 pages 6 1 2 175 0 187 0 7 0 182 194 187 5 190 0 7 5 195 197 5 see further directions page 4 9 Wing Water Mass Specified Tail tank Water Mass Total Water Mass lbs lbs lbs 55 1 81 6 2 2 57 3 83 8 82 7 109 1 3 3 86 0 112 4 Remaining volume of tail tank can be used for trimming of heavy pilots as follows For 22 lbs of pilot mass over 110 2 136 7 4 4 114 6 141 1 137 8 164 2...

Page 33: ... Warning Check thermometer regularly during flight Dump water at 5 Centigrade 41 F ballast water in wing shell and tail tank should never freeze solid See also page 3 4 4 5 11 Winch Launch or Auto Tow a Trim slightly nose heavy Trim position indicator in front of neutral mark b Adjust backrest properly See page 4 7 and tighten seat belt harness to avoid sliding backwards during acceleration and st...

Page 34: ...n Without water ballast 65 67 km h 35 36 Kt 40 42 mph With maximum water 79 81 km h 43 44 Kt 49 50 mph Circling flight Thermalling Trim stick forces to zero Best Glide Angle between 95 to 105 km h 51 to 57 Kt 59 to 65 mph High speed flight Reduce stick forces by trimming Avoid abrupt manoeuvres and check speed indication regularly to avoid exceeding limit values Warning Observe air speed limits ve...

Page 35: ...51 Kt 174 mph Example Indicated airspeed of 227 km h 122 Kt 141 mph at 6000 m 19700 ft altitude above MSL corresponds to 280 km h 151 Kt 174 mph true airspeed 4 5 15 Side slip 1 Side slip can be recommended for landing only with a small amount of air brake extension as low speed side slip is not possible because of nose heavy moment of fully extended air brakes 2 Side slip speed range up to VA 190...

Page 36: ...low 90 km h 49 Kt 56 mph With water ballast not below 100 km h 54 Kt 62 mph Warning Minimum speed increases With air brakes extended by about 10 km h 5 Kt 6 mph In rain and with air brakes extended by about 20 km h 11 Kt 12 mph Warning Side slip with air brakes extended is not recommended for landing because nose heavy moment of air brakes allows no slow side slip 4 5 17 Flight in Rain Warning Dur...

Page 37: ...s and remove with sponge 5 Check proper emptying of integral tanks when disassembled and with wings vertical drain residual water via root rib draining valve Grease root rib drain valve plunger using Vaseline and re insert before assembly 6 Check proper dumping of tail fin water tank 7 Keep all water valves open for ventilation of wing water tanks and tail fin water tank 8 Unlock wing air brake sy...

Page 38: ...tion 5 provides approved data for airspeed calibration and stalling speeds and additional unapproved information Data in the charts has been computed from actual flight tests with the sailplane in good condition and using average piloting techniques 5 2 Approved Data 5 2 1 Airspeed Indicator System Calibration Diagram on page 5 2 shows airspeed indicator error due to position of pressure ports Pit...

Page 39: ...ter ballast at 384 kg 847 lbs mass 69 km h 37 Kt 43 mph 66 km h 36 Kt 41 mph With maximum water ballast at maximum take off mass 525 kg 1157 lbs 83 km h 45 Kt 52 mph 80 km h 43 Kt 50 mph Air brakes extended at 384 kg 847 lbs mass 73 km h 39 Kt 45 mph 71 km h 38 Kt 44 mph Air brakes extended with maximum take off mass 525 kg 1157 lbs 87 km h 47 Kt 54 mph 85 km h 46 Kt 53 mph Edition July 1999 LBA a...

Page 40: ...60 80 100 120 140 160 180 200 220 240 mph 37 50 62 75 87 99 112 124 137 149 kts 32 43 54 65 76 86 97 108 119 129 m s 0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 kts 1 2 3 4 5 6 7 8 Edition Dec 2001 Revision 1 TB 8011 Page 5 3 Polar curves of LS 8 18 with 15 18 m wingspan wing loading 33 kg m without water 6 76 lbs ft resp with max mass 525 kg 1157 lbs corresponding to 50 kg m 10 24 lbs ft at 15m or 46 kg m 9 ...

Page 41: ... Pilot and parachute Warning New entry with each new weighing or when changing equipment Entry should be calculated in accordance with chapter 2 of Maintenance Manual State dimensions used State amount of permanently fitted ballast in appropriate position or none Serial Number Minimum Cockpit Load WITH WITHOUT Tail Batterie and Tail Batterie and Empty C G Max Cockpit Tail Tank Tail Tank Permanentl...

Page 42: ... C G Max Cockpit Tail Tank Tail Tank Permanently fixed Ballast Mass Tail Tank Mass position Load full empty full empty front rear Volume Date Inspector 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m 15m 18m These Minimum Cockpit Load values may only be used when the pilot can positively exclude unintentional use of tail fin water and...

Page 43: ... Ballast System 7 4 7 5 2 Fuselage Water Ballast System 7 4 7 6 Electrical System and Operation 7 5 7 7 Pneumatic System 7 5 7 8 Various Equipment 7 6 7 8 1 Expendable Ballast Trim Weights 7 6 7 8 2 Oxygen System 7 6 7 8 3 Emergency Locator Transmitter 7 6 7 1 Introduction This section provides description of the sailplanes operating systems instrumentation and other information necessary for the ...

Page 44: ...y locking B Right canopy locking and emergency jettison C Ventilation D Tow cable release E Trim locking lever F Trim lever also indicating trim position G Air brake handle G with TN8019 executed Airbrake and wheel brake H Pedal adjustment I Landing gear K Water ballast L Rudder pedals and wheel brake feet operated L with TN8019 executed Rudder pedals Edition February 2011 Revision 2 TN8019 Page 7...

Page 45: ...egral tanks inner and outer tank with related discharge valve and ventilation Ventilation of both tanks at forward lower wing root rib in front of spar through one common drain orifice A single or a double lever at right cockpit rim operates total water ballast system wing tanks and tail tank Operating the short lever alone discharges inner wing tanks and tail tank Operating the long lever automat...

Page 46: ...tem 1 Valve of inner tank 2 Ventilation tube of inner tank 3 Valve of outer tank 4 Ventilation tube of outer tank 5 Draining tube of outer tank 6 Draining valve for both tanks 7 Drive lever 8 Cable to valve of outer tank 7 5 2 Fuselage Water Ballast System Edition July 1999 Revision 0 Page 7 4 ...

Page 47: ...ittel types max 1 A quick acting for electrical variometers and turn and bank indicators Cross section of cables Battery cable min 1 mm corresponds to AN 20 cable 7 7 Pneumatic System Static and Pitot Pressure Pitot pressure port 1 at vertical tail fin below TE port Static pressure ports 2 for airspeed indicator and altimeter lower forward fuselage side statics 3 4 for variometers upper forward fu...

Page 48: ...ufacturers instructions by an adequately licences repair shop the sailplane including oxygen system must be inspected Weight and Balance Loading Instructions When using a removable oxygen unit its weight must be counted as useful load 7 8 3 Emergency Locator Transmitter ELT Permanent installation according to Maintenance Manual chapter 11 and to manufacturers instructions by an adequately licensed...

Page 49: ...e sailplane should carry its serial number 3 The serial number can be found on the type placard on the right side of the main bulkhead 4 A Maintenance Manual is issued with each sailplane 8 2 Sailplane Inspection Periods a Annual Inspection according to checklist and inspection forms provided in Maintenance Manual chapter 14 after performance of annual maintenance procedure Maintenance Manual chap...

Page 50: ...with the appropriate airplane Maintenance Manual to be sure that proper procedures are followed A Maintenance Manual is delivered with each sailplane carrying the serial number 8 3 1 Alterations or Repairs a Alterations or repairs must be accomplished by licensed personnel b Prior to any alteration the FAA should be contacted to make sure that airworthiness of the airplane is not violated c For al...

Page 51: ...pin Warning Ask the manufacturer for special advice if this has happened 8 4 Ground Handling Road Transport a Ground Towing Tow at walking speed only Use elastic cable from tow release and helper at wingtip or Use tail dolly with tow bar and sprung wheel at one outer wing Warning Towing backwards at too high speeds may yield undercarriage oscillation due to rough ground resulting in overcenter col...

Page 52: ...tail wheel Main wheel Fuselage shell in front of landing gear minimum width of support 30 cm 11 8 in Wing Right spar at inner or outer main pin hole Left forked spar at inner main pin hole At outer main pin hole only when both fork ends are supported Shell at root minimum width of support 15 cm 5 9 in Shell at outer air brake end minimum width of support 25 cm 10 in Horizontal At any place minimum...

Page 53: ...essary exposure to sunlight for instance outside parking instead of packing into the trailer Self Adhesive Tape residue should only be wiped off using white gasoline see also following recommendations from paint manufacturer For Canopy Plexiglas care never use dry cloth because of resulting static charge consequent collection of dust particles and scratching Cleanse with clear water and clean cham...

Page 54: ... These bearings should never be greased or oiled their plastic balls and aluminium alloy bearing surfaces will soon be destroyed due to collection of foreign matter These bearings are used throughout the wing control systems in the fuselage for the elevator aileron and landing gear systems Long Term Storage Preparation a Remove instrumentation and store separately b Close external pressure ports s...

Page 55: ... 9 1 9 1 Introduction This section contains the appropriate supplements necessary to safely and efficiently operate the sailplane when equipped with various optional systems and equipment not provided with the standard sailplane 9 2 List of Supplements Included Date of Insertion Document No Title of the inserted Supplement Edition July 1999 Revision 0 Page 9 1 ...

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