Civil Aviation Authority of New Zealand
23 September 2005
MEDIA RELEASE
For further information contact:
Bill Sommer
Tel: 0-4-560 9411 or 0-27-546 8216
The accident report can be viewed on the CAA web site, www.caa.govt.nz, under "Accidents & incidents - Fatal accident reports - 03/2955" or use this link: http://www.caa.govt.nz/Accident_Reports/ZK-DHA_Fatal_18Oct2003.pdf
Begins
Fatal Crash of Tiger Moth
The Civil Aviation Authority is working with the New Zealand Tiger Moth Club to produce a Good Aviation Practice booklet that will be used in conjunction with a DVD and a targeted flying training programme to highlight the problem with spinning, and give pilots tools to both avoid and recover from a spin.
These safety actions are noted in a Civil Aviation Authority accident report into the fatal crash of a Tiger Moth aircraft (ZK-DHA) at Taumarunui Aerodrome on 21 October 2003 in which both the pilot and the passenger were killed on impact.
The accident investigation determined that the aircraft was fully airworthy and pilot incapacitation was ruled out. The weather was not a factor, with calm clear conditions prevailing. The pilot in command was experienced, held a flight instructor rating, but she had relatively low experience on the aeroplane type, which has unique handling characteristics.
The pilot in command of a Tiger Moth sits in the rear cockpit. Forward visibility from this position is restricted by the aircraft structure and engine, as well as the front seat occupant. During climb, or while turning, a pilot will position the nose of the aeroplane relative to the horizon, with only occasional glances at the aeroplane instruments. If the natural horizon is obscured by high ground (which is the case when departing Taumarunui), a falsely elevated perception of the position of the horizon can be gained. This results in a higher than normal nose attitude being selected, leading to an airspeed loss. If the airspeed loss is not detected, and if there is already little margin above the stall speed, a stall and spin can ensue.
The CAA accident report concluded that an inadvertently lower than normal climb speed caused by a perceived false horizon, coupled with a low-level right turn, probably caused the aeroplane to stall and spin at an altitude too low for recovery.