Fire danger from faulty Airbus Industrie A330/A340 auxiliary hydraulic pumps has been addressed in a US Federal Aviation Administration airworthiness directive (AD), issued on 17 February, requiring their complete removal. Airbus, however, points out that all necessary corrective actions have already been taken, explaining that the electrically driven pumps (EHPs) were unnecessary during flight, but were used by maintenance engineers.
At least two aircraft suffered nearly $30 million worth of damage from wheel-well fires started on the ground by the pumps. The devices were manufactured by UK-based Vickers, and it is possible that they were responsible for the mystery destruction by fire of a brand new parked Air France A340 in January 1994.
The lead certification authority for Airbus aircraft, the French DGAC, had previously declared compulsory an Airbus "all operators telex [AOT]" dated 8 January, 1997, requiring electrical isolation of the EHPs.
The Airbus AOT had been followed up immediately by service bulletins, and an 18 June, 1997, AD from the DGAC demanded removal of the pumps. If required, replacement with different pumps was permitted. They are often used to provide hydraulic pressure to operate the cargo hold doors. Airbus says that the approved pumps, manufactured by either Vickers or Abex, are installed on the A320.
Source: Flight International
