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Air crash investigation causes and solutions. ULM Safety Day 16 March 2013. AIR ACCIDENT INVESTIGATION UNIT (Belgium). Part of the Federal Public Service – Mobility and Transport. From the investigations , determine recommendations for the improvement of flight safety .
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Air crash investigationcausesandsolutions ULM Safety Day 16 March 2013 AAIU(be)
AIR ACCIDENT INVESTIGATION UNIT (Belgium) • Part of the Federal Public Service – Mobilityand Transport. • From the investigations, determinerecommendationsfor the improvement of flight safety. • Does NOT determineliabilities nor blame. • Independent fromDGTA / DGLV. AAIU(be)
NEW EU996/2010, Regulationon Air accident investigation • Obligationtoinvestigateallaccidentsandseriousincidentswithaircraft EXCEPT Annex II aircraft (= ULM, Historicaircraft, paramotors). • We do notinvestigateall ULM accidents, onlythoseforwhichwe (arbitrary) thinksafetyrecommendationscanbe made. AAIU(be)
NEW WEBSITE: www.mobilit.belgium.be AAIU(be)
ULM AND RESPONSIBILITY • “Certified” aviationinvolves (a lot of) formal State requirementsfor Standards, Quality Control, verifications, testing, etc.., throughout the wholeaviation chain, from the designer to the end user. • “ULM” means, in generalterms, thateach element of the chain is (more) free fromformalconstraints, but remainsresponsibleforits actions. AAIU(be)
THERE ARE LESS SAFEGUARDS IN PLACE IN THE ULM SYSTEM, AND THE AVIATION CHAIN IS CONSTITUTED BY HUMANS(GENERATORS OF HUMAN ERRORS). THEREFORE THE ULM END-USER NEEDS TO COPE WITH MORE ANOMALIES GENERATED EARLIER IN THE CHAIN TO ENSURE HIS OWN SAFETY AND OF HIS PASSENGER.. maintenance assembly Experiencefeedback design AAIU(be)
ULM AND SAFETY Thanksto the safety awareness of ULM users, and overall goodquality of modern ULM airplanes, • ULM and “CertifiedGeneral Aviation (CGA)” achieve more or less the same level of safety. • Currentfatalityrate in Belgium is 5 deads /yearforboth CGA and ULM andfatal accident causes are identical. AAIU(be)
DESIGN AAIU(be)
STORM 280GS Afterpreflight (including the draining of the fuel filter), the pilots takes off, andperforms a series of touchandgoesfor 30min. Duringclimb at 400ft agl, the engine loses power, the pilot selects a field (45° from the axis) andmakesanemergency landing. (EBCF) AAIU(be)
The inspection of the carburettorrevealsthat the mainnozzle is cloggedby a grain. The design of the fuel filter (originallymaritime) is suchthat the seal maybepositionned off center andallowcontaminantsto pass through.The carburettors have no “last chance” screen filters. However, the fuel filter bowl was heavilycontaminated. There was no maintenance programme. AAIU(be)
MANUFACTURING AAIU(be)
Rainbow CHEETAH The airplane takes off withaninstructorand a passenger foraninitiation flight. In downwind, the windscreensuddenly breaks off. The dragcreatedby the openedwindscreen is very important. The pilot is forcedto land the airplane in a reed field. AAIU(be)
The windscreen is made of one sheet of polycarbonate, bent toshapeandattachedto the structurewith rivet nuts. Contact between the structureand the windscreen is protectedby a rubber seal. During ULM assembly, the rubber seal was omitted, andreplacedby a silicon joint, giving no vibrationdampeningprotection. Cracks initiated in the windscreenbyvibration, evolved, andcaused the windscreentofail. Nevertheless, cracks in the windowwerevisible long before the windscreenfailed. AAIU(be)
MAINTENANCE AAIU(be) Photo by William Larkins
RANS Coyote (Rotax 582) The airplanetook off fromUrselairfield. After a while, the engine coughed, andstopped. The pilot made a perfect emergency landing, without engine. AAIU(be)
The engine stoppedbecause the fuel pump stopped. The fuel pump is activatedpneumatically via animpulse line leadingfrom the nipple on the crankcase to the fuel pump. The tube crackedandfailed. The owner had replacedallfuellines 3 yearsbefore, exceptthisone, which was 5 yearsoldwhenitfailed (the tube was brittleandbecameopaqueand black, instead of transparent green). The materialused was poly-urethane. Alllinesshowedevidence of ageing (cracks, color,..) AAIU(be)
HM293 Pou du Ciel It was the first flight afterrepairs made on the NLG. The landing on the MLG was smooth. When the nosewheeltouched the ground, the whole NLG forkassemblyseparated. The airplanetiltedafter a short landing run. AAIU(be)
The pilot-ownerintendedtomanufacture a new NLG leg out of 25CD4S steel. He went to a reputable retailer, andgot a bar of Stub Steel, advertisedby the shop keeper, as equivalent. Whenchecking the specifications of bothmaterial, we found out thatStub Steel was not adequate for the intendedrepair, in particular the weldingcapability. AAIU(be)
Owner’s input • The owner is responsibletomaintain the airplane in safe condition. • The ownerchooses, decides, communicates,…. • The ownermaynotbe the only user, socommunicationwith the other users may prove valuabletoidentifypotentialdangers. AAIU(be)
Owner’s input • There are “operating manuals” and “operating manuals”. We saw: • Manufacturer’smanualsoverlycautious:An engine manufacturerdescribes Daily checks tobeperformed, includingverification of accessoriesmounting, condition of hoses, rubber couplingsforageing, cables, filters, wiring, etc… • Operating manual (althoughcomplyingwith the law) notshowingessentialsafetynotesfrom the airplane’smanufacturer. • Operating manual withextensivetext, essentially advertising the safety of the airplane. Look for the right information; Operationmanuals are no advertisement folders; youneedallfactualand pertinent information regardingyourairplane. • When the ownersubcontracts the performance of tasks, the Golden Rules are; “trust, but verify” and “Knowyoursupplier”. AAIU(be)
Maintenance • Maintenance checks are privilegedmomentsforanairplane; anexperiencedtechniciancandetectanomalies, (including “design” and “manufacturing” anomalies) beforetheybecomecritical. • Maintenance is notjustchanging engine oilandtyresfor the cheapestprice (OK, it is expensive). It’s an opportunity foradvisesandlearning. AAIU(be)
If an earthquake suddenly opened a fissure in a runway that caused an accident, investigators would find a way to blame it on pilot error. PILOTS AAIU(be)
Pilot: the most complex piece of technology in the ULM. • Licences: ATPL, CPL, PPL, ULM Pilot Authorization. Obtaining a pilot license is notanachievement; it is only the beginning. • Human Factors play a very important role in accidents (Get-Home-itis, haste, mission-itis, lack of knowledge, overconfidence, ...) AAIU(be)
Never trust a fuel gauge. Airspeed, altitude, or brains; you always need at least two. Assumption is the mother of all fuck-ups Good judgment comes from experience and experience comes from bad judgment. Aviate, Navigate, Communicate You don't know what you don't know. Never let an aircraft take you somewhere your brain didn't get to five minutes earlier Failingtoprepare is Preparingtofail You can only tie the record for flying low. AAIU(be)
AirlonySkylane During a training flight, with an instructor and a student on board, the airplane experienced engine problems. The airplane was flying at 2000 ft when the engine stopped. The instructor took over and selected a location for an emergency landing. The approach and initial touch down was uneventful. However, when the nose wheel contacted the ground, it sunk in the soft ground, causing the airplane to tip over. AAIU(be)
The engine stoppedduetofuelstarvation. The flight startedwith 2-fingers height of fuelvisible in the window-indicator. There are no quantitymarkings on the window, and the quantity of fuelremaining is notproportionalto the indication. Solution: calibration of the “instrument”, to get an information in the cockpit and … use a (calibrated) dipstick !!! AAIU(be)
RANS Coyote • The airplane was flying back toits home base, the Buzetairfield. • The airplane was seenturningsharp in final, stalling, and entering a spin. AAIU(be)
The pilot had startedtofly in 2005, bought his airplane in begin 2011. Total flight experience: 500FH Recent experience: from 29/7 till 21/10: 52FH He flew a lot since he purchased his ownplane, without regular support of aninstructor (onlyfortail-draggerconversion), andgained (reportedly) a lot of self-confidence. Wind: 040° 6kts Field orientation: 155°/335°. For reason of his own, the pilot was eagerto land immediately. The cross wind was considered a nuisance. Whenreaching base, in order toavoidovershooting the runwayaxis, the pilot made a sharp turn, at low speed usingtoomuchrudderandending in a skidded turn, eventually stalling the RH wing. AAIU(be)
Instructors are thereto help you!!!. It is eachpilot’sresponsibilitytomaintainandexpand his piloting skills. Instructor are thereto help you, andnotonlyduring basic training. Whenflyingalone, youmaynotrealizeyou’re making errors, andyou are thereforeunableto correct them. (Youdon’tknowwhatyoudon’tknow). Flyingwithaninstructor is not a waste of money; itcan save your life. P.S. THIS IS NOT AN ULM INSTRUCTOR AAIU(be)
Keep looking around. There's always something you've missed. Learn from the mistakes of others. You won't live long enough to make all of them by yourself. EXPERIENCE IS NO LIFE INSURANCE. EXPERIENCE AAIU(be)
Auster V – 8 Aug1950 - EBDT • After a normal take-off, the airplane made a lowpassabove the airfield and turned, climbing to 750ft agl. The enginewasthen set to idle, the airplanestillclimbing. The airplanewentinto a spin to the left. After 3 spin turns, the airplane came almost in a horizontal line of flight whenitcollidedwith the ground. • The pilot and the passengerdiedupon impact. • The engine and flight controlswereinspected, nothingabnormalwasfound. AAIU(be)
Captvlw “Vicky” Ortmans, DFC 5 confirmed Victories; 2 damaged Awarded DFC with effect from 18th September 1941.Has displayed great keenness and courage in pressing home his attacks. He has destroyed at least 5 enemy aircraft and damaged a further 2 Shot down a German ace without firing a shot. Sabena pilot after the war. www.vieillestiges.com AAIU(be)
QUESTIONS ? An accident investigation is conducted by non-flying experts who need six months to itemize all the mistakes made by a pilot in the sixty seconds he had to do anything. AAIU(be)