From Khartoum to London: 20 hours of terror aboard Sudan Air flight 150

It was more than 20 hours after his aircraft had been hijacked that Captain Abdel Hamid Hidiribi stepped out into the warmth of a sunny English afternoon, squinted and kneeled to kiss the ground.

His 186 passengers were safe, his aircraft was in one piece and, although emotionally drained, his crew of 12 had walked out unscathed. He got down to his knees and pressed his lips to the tarmac. Then he did it again.

To those watching the drama of Sudan Airways flight SUD 150, originally bound for the Jordanian capital, Amman, from Khartoum in Sudan, it was the signal to heave a collective sigh of relief. Britain's first hijack crisis in 14 years had been resolved peacefully.

The outcome could have been very different. A Jordanian embassy official who had travelled to Stansted to support the 13 Jordanian passengers and one crew member and who talked to them, said later: "The hijackers were quite aggressive at first. One man stood up with a knife just before the plane reached the Red Sea.

"He was tackled by someone else but then another hijacker stood up and said he had a grenade. In the early part of the hijacking they were a little violent. There was no food or water for people. And they would not let them go to the toilet. But once they realised they were going to England they relaxed. They saved the last of the water for children."

The official said the Iraqis described themselves as dissidents who were being forced to leave Sudan and return to Iraq. They are expected to seek political asylum.

The crew were threatened by at least six Iraqi hijackers 20 minutes after take-off from Khartoum on Monday night. The men, thought to have had handguns, demanded to be flown to Cyprus, which first denied them access, then bowed to their demands when the pilot warned of a shortage of fuel.

After refuelling, they gave Heathrow as their final destination. Although the Government's policy is not to allow hijacked aircraft to land in Britain, permission was given - possibly by Michael Howard, the Home Secretary. The Chief Constable of Essex, John Burrow, conceded that he had spoken to Mr Howard at the beginning of the crisis and at its conclusion, although he would say only that the decision was "governmental".

"The plane was headed for Heathrow but then it had to be diverted because of fog," Mr Burrow said. "We only knew at 4am that it was definitely coming here." Airport authorities and police insisted last night that the decision to let the plane land at Stansted was based solely on the weather, and not on the fact that it is regarded as Britain's "designated airport" with special facilities for hijackings.

For hours, radio and television had predicted that London's third airport would be the destination. Yet many staff were given only minutes to put their well-oiled routines into action.

At 4.28am, as the Airbus 310 emerged from the mistshrouding the airport, more than 500 police, many armed, were being deployed. Runways were closed for two hours, roads were blocked, negotiators were brought in and bomb disposal units were deployed.

But, once on the ground, the hijackers displayed no signs of hostility. Mr Burrow said negotiations, conducted from the control tower, began within an hour. Never, he said, were the passengers assaulted and at no time did the hijackers threaten to blow up the plane.

By 5.25am, the starboard front door of the aircraft was opened and, through the darkness, figures could be seen moving inside. At 6.15am, the hijackers allowed steps to be rolled up to the exit and, within 15 minutes, the first 10 hostages were released.

"The only demands made were for representatives of the Red Cross and [the Office of] the United Nations High Commissioner for Refugees to be present, together with a Mr Sadiq Sadah, a leader of the Iraqi Community Association," Mr Burrow said.

While police were despatched to find Mr Sadah, more hostages continued to be released by mutual consent, each walking gingerly past two sets of armed police, situated less than 50 yards from the plane. By 10.25am, only 39 remained on board. Three were taken to hospital but not, according to police, with ailments caused by the hijackers.

By noon, when Mr Sadah arrived - his suitability as a negotiator having been assessed by police - it was almost over.

"When we told them that Mr Sadah was in the tower, they agreed to surrender," said Mr Burrow. After letting their captives go, the Iraqis sent out their families. Each, some only children, put their hands in the air or on their heads. Then came the hijackers and crew.