David Learmount/COPENHAGEN

ASSERTIVE ACTION, by cabin crew, could greatly increase passengers' chances of survival after a crash-landing, new research has shown.

Assertively applied emergency-evacuation drills can accelerate airline-passenger emergency-evacuation markedly, the study demonstrates, whereas, non-assertive cabin crew make little difference to egress rates.

The findings come in a study entitled Cabin Staff Behaviour in Emergency Evacuations by Professor Helen Muir of Cranfield University, in the UK. It follows the latest phase of a cabin-safety research programme for the UK Civil Aviation Authority and US Federal Aviation Administration.

The report observes that, although there has been a "dramatic" reduction in airline accident rates over the last 20 years, there has been "a less dramatic reduction in the fatality rate of those on board". It adds: "The forces involved in non-survivable accidents are usually of such magnitude that no change to cabin-safety regulations would be likely to enhance survival rates. Thus, any programme of cabin-safety research should address those factors which will enable the probability of surviving a technically survivable accident to be improved."

Muir's study addresses the "procedural" aspects of emergency evacuation, and employs the now-established "competitive" technique to engender "passenger" behaviour similar to that, which would occur in an emergency. Volunteer passengers were paid a bonus for being among the first 75% to leave a Boeing 737-200 cabin simulator.

A series of evacuations, using one door only, showed the following average times for the first 75% of passengers to leave:

with two assertive cabin crew: 57.97s;

with one assertive cabin crew: 63.2s;

with two non-assertive cabin crew: 76.59s;

with no cabin crew: 79.68s.

Assertive cabin-crew behaviour included "calling passengers to exits and actively pushing them through exits as rapidly as possible in a highly active, but non-aggressive, manner".

Operating a new incentive technique, which Muir calls "collaborative", in which all of the "passengers" were offered a bonus, if they all successfully evacuated the cabin simulator within 90s, produced a similar ranking of results, for two and one assertive cabin crew but, with non-assertive crew, the evacuation took even longer than with no crew at all.

Source: Flight International