Air Accident Investigation Branch Wants More Training For Sport
Pilots
Since 1989, there have been as many
as 265 gyroplanes flying in the United Kingdom. Also since 1989,
there have been 15 fatal gyroplane accidents in the UK. That works
out to a fatal accident rate of 27.1 for every 100,000 hours of
flight time. So says the British Air Accident Investigation Branch.
The fatal accident rate for all other forms of aviation in Britain
is 1.1 per 100,000 flight hours.
Now, AAIB has issued a report critical of gyroplane technology
and the training of gyro pilots. The report, which focused on the
July 29th, 2003 crash of a modified Ponsford Bensen B8MR, in which
44-year old Ian Broderick Pitt-Steele of, Gardyn Croft, Taverham,
on his first unsupervised solo flight in a gyroplane, plunged more
than 250 feet to his death.
Porpoising
AAIB investigators wrote:
On the morning of 29 June... G-BIGU appeared to takeoff from
Runway 02 and fly a short distance to the north before turning back
towards the airfield. The aircraft was seen to fly along the runway
in each direction and some witnesses were aware of G-BIGU gently
"porpoising" as it flew along.
Estimates of the height of the gyroplane during this time varied
between 10 and 20 feet above the runway and also between 400 and
500 feet but displaced to one side of the runway. With the
variation in height estimates from the witnesses, who were both
pilots, it was possible that this "porpoising" occurred at
different times. None of the witnesses were concerned by the
maneuvers. One witness, who saw the last moments of flight, was
standing by the airfield hangar looking towards the east. He saw
G-BIGU in a downwind position for Runway 20 at about 250 to 300
feet AGL and at an estimated speed of about 45 kt.
The gyroplane appeared to be stable and in level flight when the
witness heard a single "bang" and saw an immediate change in
attitude. The aircraft pitched nose down and fell vertically to the
ground. This witness also commented that he had heard a "broken"
radio transmission sometime prior to the accident sequence; with no
other club aircraft flying, he assumed that the pilot of G-BIGU had
made this transmission.

The Cause
In its synopsis, the AAIB wrote:
[The accident] resulted from the rotor blades striking the
rudder, which rendered the gyroplane uncontrollable. Witness
accounts indicated that G-BIGU was flying straight and level at a
reasonable speed just before this event, although there were
reports of possible 'over-controlling' during the flight. The
specific reason for the rotor blades striking the rudder could not
be determined but a pilot induced oscillation appeared to be the
probable cause.
An examination of the aircraft, and subsequent computer
modelling by the University of Glasgow indicated that the aircraft
could have had poor longitudinal stability characteristics. The
investigation also highlighted the poor safety record of gyroplanes
in general compared to other types of recreational aircraft.
Accordingly, recommendations have been made concerning the approval
of gyroplanes and the training and licensing of gyroplane
pilots.
The test flight of G-BIGU that was carried out on behalf of the
Popular Flying Association did not appear to have been flown in
accordance with the interpretive material of the stability
requirements of British Civil Airworthiness Regulations Section T.
The flight test report did not include any data to support the
opinion that the aircraft met the dynamic stability criteria of
section T. The format of the form used for the flight test report
was poor in that it did not include fields for recording the data
required by British Civil Airworthiness Regulations Section T.

Technical Problems?
The AAIB was highly critical of the procedure by which the
aircraft itself was certified as airworthy:
The test flight of G-BIGU that was carried out on behalf of the
Popular Flying Association did not appear to have been flown in
accordance with the interpretive material of the stability
requirements of British Civil Airworthiness Regulations Section T.
The flight test report did not include any data to support the
opinion that the aircraft met the dynamic stability criteria of
section T. The format of the form used for the flight test report
was poor in that it did not include fields for recording the data
required by British Civil Airworthiness Regulations Section T.
AAIB recommendations include:
- Better gyroplane pilot training, especially in type and
especially in flight
- Differentiating between hours spent "wheel balancing" (a
maneuver whereby the pilot lifts the nose of the gyroplane off the
ground as he moves down the runway, but does not actually take
off)
- Ensuring gyroplane test pilots are trained to evaluate aircraft
performance
Finally, on the issue of flight
certification for gyroplanes, the AAIB concluded:
The Popular Flying Association also endorsed the recommendations
and stated: "We are now working with the CAA Projects Department
and Flight Department to develop a new gyroplane flight test
schedule specifically to investigate ultralight gyroplanes against
the Section T handling requirements, and to train selected
experienced gyroplane pilots in the test methods and reporting
procedures. We are of course working with the CAA on the
re-evaluation of existing types of gyroplanes against Section T
handling requirements which we see as a very positive step towards
addressing the high accident rate on this class of aircraft".