Ramon Lopez/WASHINGTON DC
COVERS USED to protect aircraft static vents during maintenance should incorporate conspicuous warning flags, the US National Transportation Safety Board (NTSB) has recommended.
This is a reaction to reports from the Peruvian authorities that an Aero Peru Boeing 757 crashed because its static vents had been taped over. The vents provide altimeters, airspeed indicators and air-data computers with the ambient air pressure.
When wreckage recovery started following the 2 October accident, three of the aircraft's static ports, were found to be covered with tape. All 70 passengers and crew perished when the aircraft crashed into the sea at night in poor visibility (Flight International, 13-19 November, P12).
Data from the cockpit-voice and flight-data recorders reveal that airspeed and altitude indications were incorrect once the aircraft began to climb.
The NTSB says that, while the aircraft was being polished immediately before the fatal flight, maintenance personnel taped over the static ports, and comments: "The circumstances of this accident raise concerns about the practice of applying tape to static ports, and the potential for catastrophic results."
McDonnell Douglas and Airbus Industrie provide bright, flagged, protective static-vent covers, and the NTSB recommends that the US Federal Aviation Administration should require amendment of all aircraft-maintenance manuals to include the use of similar equipment.
The February Birgenair 757 accident off the Dominican Republic has been officially attributed to a blockage in the pitot-tube airspeed sensor, contaminated because the protective cover was left off for a long period while the aircraft was on the ground.
Source: Flight International
