The four officers, P N Bahuguna, western regional secretary of the ATC Guild, M K Sinha, P Srinivas and Sudhanshu Gupta, moved anticipatory bail applications and appeared before Principal Sessions Judge A S Aguiar this evening.

The four officers had been dismissed by the management yesterday and warrants were issued against them by airport police under various sections of Indian Penal Code and clauses pertaining to `suppression of unlawful action against civil aviation safety' under the airport code of conduct rules.

The officers are also preparing to move Bombay High Court challenging their dismissal, maintaining that honest ATCs had been penalised by the management with ulterior motives and air traffic services rendered by ATCs at Mumbai airport were safe as anywhere else in the world.

Meanwhile, ATCs continued their work-to-rule agitationand delayed domestic and international flights for the 18th day today.

Though the situation at Mumbai airport improved marginally as most incoming flights were promptly given clearance to land, out-bound flights of all domestic operators, including Indian Airlines, were delayed for five to 25 minutes since early morning.

According to sources at Mumbai airport, though duration of delays reduced considerably, flights were being deliberately delayed by ATCs. ``It would be wrong to say the situation has returned to normalcy,'' said an airport official.

``These chaps have been restrained from continuing their agitation by city civil court and issued a contempt notice by Delhi High Court. Even sacking of their leaders has had little impact on agitating ATCs, and flight safety and lives of passengers were threatened again as flights were deliberately delayed. The situation demands sterner action. ATCs should not be allowed to blackmail the nation,'' said an airline employee.

Another airline source said itwas impossible to presume which flight would be delayed, as permission to take off was not given at the eleventh hour even after passengers had boarded the plane. Generally if the delay was caused due to a technical fault or other such reason, the new flight time would be declared well in advance or flashed on monitors at the airport.

``But in this case, while the monitor would show the flight is on time, the aircraft would not be allowed to either take off or land by ATCs, leaving both pilots and passengers at their mercy. Just imagine sitting in a stationary aircraft for over two hours, though the actual flight time to a destination would be under an hour,'' he explained.