1974 Norfolk mid-air collision
This article relies largely or entirely on a single source. (March 2024) |
Accident | |
---|---|
Date | 9 August 1974 |
Summary | Piper PA-25-235 Pawnee |
Operator | ADS (Aerial) Limited |
Registration | G-ASVX |
Flight origin | Broomfield |
Crew | 1 |
Fatalities | 1 |
Survivors | 0 |
The 1974 Norfolk mid-air collision happened on 9 August 1974 at
Aircraft
The Pawnee
Accident
The Pawnee had departed earlier on 9 August 1974 from
Investigation
Both aircraft were found to have been maintained correctly and were legally authorised for the flights. Farmwork Services, who had chartered the Pawnee, had informed the local police authority about their proposed operation and type of chemical to be used. Nothing in the regulations required them to inform the military although Farmwork Services had, as usual, informed nearby RAF Marham (an operational airfield about 8 nmi (15 km) from the accident) that they would be spraying an extensive area of Norfolk between June and the end of August 1974.[2]
Investigation of the wreckage failed to determine if either had a working anti-collision light and it was only possible to determine the height of the accident by the use of eyewitness accounts. The collision occurred in good visibility at an estimated height above ground level of 300 ft (91 m). The investigation could find no evidence to suggest that either of the pilots had a medical problem or that either aircraft had any defect that would have contributed to the accident.[2]
The rules of the air state that the Pawnee should have given way to the Phantom which was closing from the right. But it was accepted that at a closing speed of about 400 kn (740 km/h) the time needed by the Pawnee pilot to assess the situation and execute a manoeuvre was minimal. It was also a requirement of the Phantom pilot to make sure that he did not collide with the Pawnee but clearly in this accident the lack of time was an element. Also the military aircraft had only just turned on to the heading and with the Pawnee 15° to his left the view may well have been obstructed by the Phantom's canopy frame.[2]
While it accepted the need for the Royal Air Force to practise low level high-speed flying the investigation report was concerned about the lack of information on the military low-flying route available to civil pilots, particularly those involved with crop spraying, pipeline, and powerline inspection.[2]
Cause
The investigation determined "The accident occurred because neither pilot saw the other aircraft in time to avoid collision. The 'see and be seen' principle was inadequate for preventing collision in the circumstances that existed. A significant feature which contributed to the accident was the absence of any system for co-ordinating military and civil low flying activities in the low flying areas and link routes."[2]
Recommendations
The accident report made seven recommendations:[2]
- That the location and vertical extent of the low flying areas and link routes should be made available.
- Private pilots should be alerted to the nature of military low flying activities and the need to avoid them.
- An advisory service be provided to enable civil pilots to co-ordinate their activities with the military.
- That civil aircraft involved in low flying activities should be painted as conspicuously as possible and fitted with high-power collision warning lights preferably strobetype. Also recommended that the military consider fitment of strobe type high-power collision warning lights to aircraft engaged in low level training.
- The military review their need for airspace for low-level high-speed operations and withdraw any areas not needed.
- That the upper limit of the military low flying link routes be limited to 1,000 ft (300 m) instead of 2,000 ft (610 m), if not possible then 1,500 ft (460 m) should be considered.
- That the rules of the air be amended to allow aircraft with the right of way to climb and if necessary pass over the other aircraft.
References
- ^ a b c "Collision over Norfolk". Flight International. 106 (3413). IPC Transport Press Ltd: 146. 15 August 1974. Archived from the original on 21 October 2012.
- ^ ISBN 0115114262, retrieved 28 September 2009