DAVID LEARMOUNT / LONDON
Pilots may be reluctant to use emergency code says AEA
The Association of European Airlines (AEA) has told the US Federal Aviation Administration that it radically disagrees with the agency's proposal for continuous, uninterruptible transponder operations.
It says the FAA's notice of proposed rulemaking (NPRM), resulting from ideas spawned immediately following the 11September 2001 attacks on New York and Washington, is no longer needed because of other measures taken since then, and may have a negative impact on flight safety.
On 11 September the terrorists switched off the transponders on three of the four aircraft they hijacked so that civil air traffic controllers could no longer see them on radar. Within days of the event it was proposed that it should be impossible to switch the transponder off in flight. The NPRM, applying to any aircraft operating in US airspace, proposes that the hijack code 7500 should be easy to set on transponders, and once selected it should not be possible to deselect it, switch the transponder off, or disable it - for example by tripping the transponder's circuit breaker manually.
The AEA lists a number of objections to the proposal, including:
Since the proposal was conceived, airlines have invested in strengthened cockpit doors and locks and crews have been trained to deal differently with hijackers, so the need for a special transponder should be subjected to a revised cost-benefit analysis; European flightcrews oppose the idea, and "it is doubtful whether any flightcrew would activate the hijack signal knowing that this could result in his aircraft being shot down"; The AEA says that the FAA has not properly investigated the negative flight safety implications such as false alarms or inadvertent hijack signal operation followed by shoot-down; No International Civil Aviation Organisation standard or requirement for this equipment has been mandated. "The lack of harmonisation at an international level could create further negative flight safety impact, in particular for international operating airlines and flightcrews," the AEA says.The AEA also notes that both the European Civil Aviation Conference and Eurocontrol have advised alternative measures rather than the special transponder. These include procedures which optimise the sharing of civil ATC and military air defence radar information - a process which is also now in progress in the USA.
Source: Flight International
