Accident Labahn Hitch Hiker XC ,
ASN logo
ASN Wikibase Occurrence # 218872
 
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information. If you feel this information is incomplete or incorrect, you can submit corrected information.

Date:Friday 24 June 1988
Time:16:05
Type:Labahn Hitch Hiker XC
Owner/operator:Private
Registration:
MSN:
Fatalities:Fatalities: 1 / Occupants: 1
Aircraft damage: Destroyed
Category:Accident
Location:3.5km SSE of Officer, VIC -   Australia
Phase: Manoeuvring (airshow, firefighting, ag.ops.)
Nature:Test
Departure airport:Beaconsfield, VIC
Destination airport:Beaconsfield, VIC
Investigating agency: BASI
Confidence Rating: Accident investigation report completed and information captured
Narrative:
While flying at about 500 feet above ground level the aircraft evidently experienced severe vibration, and the inboard half of the right aileron was torn from the wing. The pilot attempted to deploy the parachute system, but the rigging lines wrapped around the propeller shaft. As a result, the parachute canopy did not open, but trailed between the propeller and the tail plane. The aircraft subsequently stalled and spiralled to the ground. When impact occurred, the complete left aileron was seen still falling. It was found 60 metres short of the aircraft impact site and the right aileron was found 148 metres short of the impact site. There is no known technical data available for this prototype aircraft, on which the control surfaces were not mass balanced. The pilot had experienced probable in-flight flutter on an earlier, different ultralight which he had designed and built. He had eliminated the problem by mass balancing the ailerons. An airspeed of about 80 knots could be considered critical for the initiation of flutter of unbalanced control surfaces on ultralight aircraft. From measurements and numbers recorded by the pilot on his map, it was concluded that the aircraft had probably been travelling in excess of this speed. Control surface flutter may have also been induced if some element of the control system had failed or had not been assembled or maintained to minimize flexibility and mechanical tolerances. A detailed inspection of the wreckage has determined that the control rod support lugs on the right aileron control horn may have failed along the weld line. There may also have been torsional flexibility of the aileron and the wing, which could have led to flutter at high speed.

Accident investigation:
cover
  
Investigating agency: BASI
Report number: 
Status: Investigation completed
Duration:
Download report: Final report

Sources:

https://www.atsb.gov.au/publications/investigation_reports/1988/aair/aair198801417/
https://www.atsb.gov.au/media/26843/aair198801417.pdf

Revision history:

Date/timeContributorUpdates
01-Dec-2018 23:32 Pineapple Added

Corrections or additions? ... Edit this accident description

The Aviation Safety Network is an exclusive service provided by:
Quick Links:

CONNECT WITH US: FSF on social media FSF Facebook FSF Twitter FSF Youtube FSF LinkedIn FSF Instagram

©2024 Flight Safety Foundation

1920 Ballenger Av, 4th Fl.
Alexandria, Virginia 22314
www.FlightSafety.org