Eight people died when helicopter and small aircraft collide in air

On March 5, 2007, an aviation accident occurred in Zell am See, Salzburg, Austria. In the collision between a Type AS 332 “Super-Puma” transport helicopter and a Type DV 20 “Katana” motorized aircraft, the pilot of the small aircraft and 7 occupants of the helicopter were killed.

Fig.1 The crew of the helicopter immediately before takeoff.

At around 9.50 a.m. the private Katana small aircraft takes off from Zell am See airfield towards the east towards Lienz in East Tyrol. Lienz is west of Zell am See, and so the pilot has to make a 180° turn in the climb after takeoff. At the same time, a Super Puma transport helicopter takes off from Kaprun in the south with 7 passengers and flies north. The helicopter crosses the airspace of the Zell am See airfield. The pilot of the helicopter is informed by the management of the Zell am See airfield about the takeoff of the Katana small aircraft and makes visual contact with the small aircraft taking off to the east. Shortly afterwards, the crew lost sight of the small aircraft as it was flying in the opposite direction (east).

Fig.2 Collision sketch of the accident.

In order to reach its destination of Lienz in East Tyrol, the small aircraft turns 180° towards the west, unnoticed by the helicopter crew. The mandatory reporting point above Lake Zell will be overflown. While still climbing with limited visibility ahead, the small aircraft collided almost head-on with the helicopter at a height of approx. 800 m and both aircraft crashed over the Schmittenhöhe ski area.

Fig.3 Rescue personnel on the wreckage.

Fig.4 The wreckage.

Coming from below, the small aircraft crashes into the front right side of the helicopter at the height of the co-pilot. Both aircraft are torn into several pieces in the collision. The debris is scattered over a forest area of approximately 20 hectares. All aircraft debris and the bodies of the victims were recovered by local emergency services. The victims’ bodies were sent to the Salzburg forensic medicine department for autopsy and identification.

Fig.5 Collection of post-mortem dental data by the forensic odontologist.

Fig.6 Makeshift setup for x-raying the individual parts of the jaw with a stationary 35mm x-ray machine.

Fig.7 Taking fingerprints from the victims.

Since the personal details of the victims involved are known in this closed event, the police can begin collecting ante-mortem (AM) data such as dental status, fingerprints and DNA samples. The first AM dental data of the pilot of the Katana small aircraft is already available on the second day after the accident, and the first victim can be successfully identified based on the dental status. AM dental data is submitted for 6 of the 8 victims and they can be clearly identified from this data. The dental data for 2 victims cannot be provided because no treating dentist can be identified. One of the two victims is from France and the second victim had recently moved from the former East Germany. All 8 victims are additionally identified through fingerprints and DNA analysis.

Fig.8 High levels of destruction and injuries to the victim due to the strong forces acting on them.

Fig.9 Right maxilla, 1st quadrant.

Fig.10 Fragment of the right mandible of the 4th quadrant.

The individual locations where the victims were found are documented, numbered and recorded on site. The 8 victims are then transferred to the forensic medicine center in Salzburg and subjected to a detailed forensic medical examination with DNA analysis and toxicological examination. In addition to collecting the exact postmortem (PM) dental status, fingerprints are taken and the personal items that the opera carried with them are examined. The investigation of victims will be carried out in accordance with the Interpol DVI guidelines and the relevant DVI forms (F1 and F2) will be used for this purpose.

Fig.11 Left: cut off the front of the upper jaw with the diastema, right: the posterior part of the right and left mandibles.

Fig.12 Skull of one of the victims.

The two pilots realized too late that the aircraft were on a collision course. Due to both pilots’ limited field of vision and the fixation of their gaze on the slope structures, mutual perception only occurs at the earliest 5 s before the collision. Until 10 s before the collision, the aircraft can only be seen as dots, only then does their size change. From the perspective of both pilots, the other aircraft is below the horizon over terrain, making detection even more difficult. Statistically, a time period of 5.4 s from the first detection to the start of the aircraft’s evasive movement is determined in order to prevent the accident. This leaves only 5.4 s for perception. In this short period of time, it is not possible for both pilots to initiate the correct countermeasures. The collision is inevitable.