A person familiar with Continental's operations said the airline was considering a surcharge for fuel.

A Delta spokesman said the airline was considering a big purchase but would have no announcement until later in the year.

Among the alternatives the airline has considered was to file for protection under Chapter 11 of the bankruptcy code.

If fuel prices continue at present levels, he said, the airline would consider selling assets like some international routes.

Most airlines do not consider medical tests an emergency.

Other airlines considered the proposal but expressed concerns about the pace of change and the loss of control over pricing.

The airlines are also considering ways to create a kind of frequent-flier security pass for those willing to submit to a more intense identification check.

If a child being walked past the security area runs to someone waiting, the airline considers its duty to identify the "responsible adult" fulfilled.

Even if we lowered it, the airlines would still not consider putting a stop to the practice of flying empty planes.

He also suggested the airlines should seriously consider mergers and alliances.