Covering form of preliminary or final report
| Date of event : | 2019-10-12 |
| Incident number : | CZ-19-0973 |
| Report : | Final report |
| Place of event : | Grassland near the Mnichov village (Vrbno pod Pradědem) |
| Registration mark : | Accident |
| Weight category MTOM: : | <2250 kg |
| Type of operation : | Recreational and sport aviation |
| Plane / SFM : | Gliders |
| Type of plane / SFM : | SZD-42-2 Jantar 2B |
| Health effects of event : | The fatal injuries |
| PDF document : | 
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Description:
SUMMARY
Synopsis
On 12 October 2019, the glider pilot took off in aerotow from the Mikulovice airport making use of wave flow behind the range of the Jeseníky mountains.
After approx. 4.5 hrs of flying at high altitude, the pilot lost control of the glider whose wing structure was shortly afterwards damaged at the point of connection of both halves. The glider disintegrated in the air and subsequently crashed on the ground. The fuselage and tailplanes were completely destroyed due to the impact on the ground. Following intensive search, both wing halves and the elevator were found intact at the distance of approx. 7.1 km east of the fuselage impact place and were located 2.6 km and 2.0 km apart, respectively. The pilot’s body tissues were found in the immediate vicinity of the impact site and pilot’s substantially crushed corpse was located in the impact crater among fragments of the completely destroyed glider fuselage.
Factual Information
Before leaving Warsaw on 10 October 2019, the glider pilot registered online in the registry of pilots – participants in the wave season at LKMI starting from 1 September 2019. He then contacted his aeroclub fellow member by phone to inquire about weather and operating conditions at the Mikulovice airport where the said fellow member has been flying in the Wave Camp since 8 October 2019. The pilot arrived at LKMI on 11 October 2019 at 1 a.m. local time and, as it was not his first time there, he parked his car with a towing dolly without any problems on the airport premises, checked in and went to bed. After he woke up at 05:19, he contacted his partner via an SMS message, which was soon answered with a request for take-off assistance. 30 minutes later, he was at the place of take-off to hold the partner’s glider wing during take-off run. After that, he returned to the place where his towing dolly was parked and started preparing the glider for the flight. When his partner was landing approx. an hour later, he had already assembled the glider.
On the same day, both pilots took off from LKMI with their gliders. The pilot’s partner took off at 10:22 and the pilot at 11:24. Following a 5.5-hour and 3.5-hour flight, respectively, they landed at the airport of departure. Each one individually towed his glider from the runway to the area in front of the hangar where there are glider anchorage points. Having anchored the gliders, they went to the aeroclub’s service building where they were told that they would be accommodated in one room for capacity reasons. The pilot vacated his room and moved to the fellow member’s room. They spent nearly all the rest of the day there. They talked, among other things, about the flight during which the pilot climbed to 3,500 m MSL without experiencing any problems. He also mentioned that on the next flight on the next day, he would like to achieve 6,500 m MSL to obtain the third diamond. They had a light dinner, which they prepared for themselves, and went to bed at about 9 p.m. local time.
At 06:15, the glider pilot took off in aerotow behind Maule M-5-201C from RWY 23. According to the timekeeper’s logbook, it was the eleventh take-off in the air traffic at LKMI on 12 October 2019. After about 15 minutes of flight in aerotow, the pilot disengaged the glider from the towing aircraft and after about 4.5 hours the accidental witnesses saw individual parts of the glider falling from a very high altitude accompanied by an unusual noise.
Analyses
The glider pilot held appropriate competence and medical certificates. He had skills in piloting several types of gliders. Over the last 10 years, he was regularly flying the SZD 42-2 Jantar 2B type and was familiar with its operational characteristics. He confirmed at registration that he was familiar with the rules and updates of the Long Wave Flying Guidelines behind Jeseníky for the given wave season binding on pilots flying in long wave behind Jeseníky and taking off from LKMI. He possessed the pilot skills to conduct a long wave flight behind the range of the Jeseníky mountains, but had minimum practical experience in flying above 4,000 m MSL.
The pilot took off in aerotow and departed from LKMI to the area of expected climb in a standard manner. After disengaging the glider from the tow plane, he followed the flight in the wave flow.
The critical situation occurred probably when the pilot did not recognise in time the danger of emerging hypoxia, which affected him so much that he gradually lost the ability to pilot the glider safely. In a state of partial unconsciousness, he was unable to recognise the danger arising from the extreme increase in airspeed. The significant excess in the maximum permissible speed resulted in critical loading of the glider structure and exceeded the strength limits not only in terms of the combination of wing bending and torsion, but also due to flutter, which clearly contributed to the destruction of the elevator. After the separation of both wing halves and elevator from the fuselage, the debris of the glider was falling uncontrollably to the ground.
Considering that the glider had the tailplanes attached until impact on the ground, it is likely that the tailplanes exerted a force that caused the extreme rotation of the fuselage during the fall to the ground. The biochemical examination of the pilot’s psychosomatic condition showed that the pilot was conscious and fully aware of the critical situation for several tens of seconds before the fuselage impacted the ground, yet he did not attempt to make an emergency exit. His failure to drop the glider’s cockpit cover and subsequently leave the cockpit can be explained by the fact that the inertial forces of the extreme rotation prevented the pilot from opening the cockpit canopy locks.
The location and condition of the found wreckage clearly showed that the glider had been destroyed by a breach of structural integrity in high altitude flight and only subsequently by the forces applied during the impact on the ground. Upon investigation of the place of air accident and subsequent technical investigation of the glider wreckage on the AAII premises, no facts that would indicate that the air accident was caused by a technical defect of the glider were detected.
Conclusions/Causes
The cause of the accident was a confluence of factors where the glider pilot with little experience in flying at altitudes above 4,000 m MSL underestimated the effect of hypoxia on the human body. Probably due to inappropriate use of oxygen equipment, he got into a state in which he was gradually losing the ability to react adequately to the critical situation that arose, which led to the glider getting into a mode that resulted in the breach of structural integrity in flight.
Attached final report in PDF file is in original Czech language.