Flygplan har kraschat utanför Umeå – nio personer döda (2019-07-14)

- There was a fatigue crack on the wing strut. Because of the damage to the aircraft it was not possible to investigate the mechanism of the fatigue crack formation. It is possible that, in addition to the stress caused to the aircraft by short flights and high takeoff weights, the temperature changes caused by the exhaust gas stream as well as vibration contributed to the fatigue cracking.

- The nature of skydiving operations generated many takeoffs and landings in relation to flight hours. A significant part of the operations was flown close to the maximum takeoff weight. These factors increased the structural stress.

- The pilot’s limited flight experience on a powerful turboprop aircraft, his inadequate training as re- gards aircraft loading and its effects on the centre of gravity and airplane behaviour, the high weight of the aircraft and the aft position of the CG in the beginning of a new jump line and, possibly, the pilot’s incorrect observation of the actual visual horizon contributed to the onset of the occurrence.
During the turn to a new jump run the aircraft began to descend and very rapidly accelerated close to its maximum permissible airspeed. The pilot did not immediately realise this.

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L2014-02
Aircraft Accident Resulting in the Death of Eight Skydivers at Jämijärvi on 20 April 2014

- The structural modifications on the wing increased the loads on the aircraft and the wing struts. Their effects had not been established beforehand. The kit manufacturer was aware of the modifications. No changes to the Permit to build were applied for in writing regarding the modifications. Neither the build supervisor nor the aircraft inspectors were aware of the origin or the effects of the modifications.

As a result of the investigation the Safety Investigation Authority, Finland issued five recommendations; three to the Finnish Transport Safety Authority, one to the European Aviation Safety Agency and one to the Ministry of Social Affairs and Health.

The Finnish Transport Safety Authority should:

- When required, limit the number of occupants in experimental aircraft and their use in skydiving operations based on risk considerations.

- Ensure that the experience and training of persons that supervise and inspect experimental air- craft construction meet the requirements of construction and modification control, and

- In conjunction with the recreational aviation safety project, ensure that the Finnish Aeronautical Association prepares generic guidelines for skydiving operations, around which associations build a training programme and proficiency checks for jump pilots.

The SIAF recommends that the European Aviation Safety Agency prepare specified theoretical knowledge and flight training requirements for pilots-in-command in skydiving operations.

The SIAF repeats the recommendation to the Ministry of Social Affairs and Health which was originally issued by the Investigation Commission of the Kauhajoki School Shooting in 2008. The Ministry should take steps to ensure that the plans, resources, responsibilities, and competent leadership for the provi- sion of psychosocial support in major crises are available regardless of where the accident takes place or where the people involved come from.