THE THEORY that the ValuJet McDonnell Douglas DC-9-30 accident on 11 May was linked to the unauthorised freighting of oxygen-generator units has been reinforced by the investigator's discovery of pieces of the canisters embedded in a tyre from the forward cargo hold.
At the time of going to press, the US Department of Transport was preparing an order banning passenger airliners from carrying oxygen generators as cargo.
US National Transportation Safety Board (NTSB) investigators also say that the canisters may have been packed without plastic safety caps covering the canister's firing mechanisms. One possibility under investigation is that triggered canisters started a fire among airfreighted tyres, the smoke eventually working its way into the cockpit and passenger cabin.
Argument has begun about how fully charged oxygen generators, labelled as empty, came to be in the hold. ValuJet insists that an employee of SabreTech, the Miami aircraft-repair company contracted to the carrier, filled out the shipping ticket for the five sealed cardboard boxes containing the oxygen canisters, describing the units as empty.
SabreTech says that the time-expired canisters, which had been removed from the passenger emergency-oxygen system of three ValuJet MD-80s, were being returned to ValuJet without shipping instructions.
Meanwhile, ValuJet has halved its flight schedules so that detailed inspections can be made of its 51 aircraft. This action will hit the low-fare new-entrant's earnings. Peak daily departures have been reduced to 160, from 320. ValuJet does not expect to return to a full flight schedule until the end of the year.
As part of its cutback, ValuJet is to delay acceptance of a McDonnell Douglas (MDC) DC-9 which had been due for delivery in May. Three other DC-9s and two MDC MD-80s scheduled for later this year may also be delayed.
Source: Flight International
