By Leithen Francis in Singapore

Japan’s Civil Aviation Bureau (JCAB) has asked Bombardier to improve the reliability of Dash 8 Q400s and also called on the Canadian civil aviation authority to assist.

“There have been far more problems that have occurred in Japan with the Q400 than with other newly developed aircraft,” says a source at the JCAB in Tokyo. “Japanese operators have informed Bombardier about the troubles and they want to [see] improvements to the design of the Q400,” says the source, referring to Air Central, All Nippon Airways’ Air Nippon Network and Japan Airlines’ Japan Air Commuter (JAC).

“If these design changes can be accomplished then the Japanese carriers think the troubles will decrease.”

The JCAB source adds: “We have asked Bombardier to listen to the Japanese carriers’ concerns and review their designs in order to reduce the operational troubles.”

The source adds that the Japanese regulator has also “requested the TCCA [Transport Canada] co-operate and assist in this issue”.

Japanese operators have already made some improvements to the Q400 – in accordance with the aircraft manufacturer’s service bulletins – but other changes are taking longer to achieve because Bombardier has had to talk to its suppliers, adds the source.

Bombardier says that it is aware that there have been “technical issues, and is very conscious that they have caused schedule interruptions. Those issues are being addressed by a ‘Working-Together’ plan, involving our maintenance and production people and the two Japanese airlines. We’re already seeing an improvement in the dispatch reliability, and the two airlines are fully satisfied that the situation will be resolved.”

Concerns over the Q400 have already appeared in Japan’s media, with several newspapers reporting on an ANA/JAC survey into the Q400. The survey, covering the period 28 June 2003 to 20 May 2006, found there were 52 cases where Q400s had made emergency landings or had to return to departure airports. Of these cases, 49 stemmed from problems with the aircraft, and included difficulties with: the flight control system; landing gear; engine oil pumps; and hydraulic pressure systems.

Problems with the landing gear are of particular concern to the airlines, says the JCAB source, adding that there have been incidents where the landing gear has failed to deploy or retract.

JAC accounted for 19 of the 52 incidents, while Air Nippon Network and Air Central accounted for 22 and 11 respectively. ANA group had most of the incidents because it operates a larger fleet of Q400s, says the airline.

Source: Flight International