Diplomats for the UK, Ireland and the US are working to secure the release of a group of pilots, including a maverick British aviator, grounded by Ethiopian authorities during an attempt to fly the length of Africa in vintage planes.

Maurice Kirk, the British former drinking friend of the late actor Oliver Reed, who was once arrested for landing at George W Bush’s Texas ranch, is among those stranded in Ethiopia.

A retired vet, Kirk, 71, had caused alarm when he and his 1943 Piper Cub plane disappeared earlier this week near the border of Sudan and Ethiopia, prompting a search-and-rescue operation.

Happily, he and the rest of those taking part in the Vintage Air Rally (VAR) – about 40 people in all – managed to touch down safely in Gambella, Ethiopia.

Not so happily, the party did not receive the warmest of welcomes. A statement from the VAR organisers said: “The Ethiopian authorities have elected to allocate accommodation at the airport rather than permit them to proceed to their pre-booked hotel. The reasons for this, at this time, are not 100% clear.

“There is no possibility to communicate with them but all participants, including Maurice Kirk, are safe and accounted for. The UK Foreign and Commonwealth Office is aware, is talking with other embassies, and is negotiating on their behalf. We have no further information because of the lack of communications. More information to follow when available.”

Facebook Twitter Pinterest Maurice Kirk and his damaged vintage plane Liberty Girl in 2007. Photograph: Pat Wellenbach/AP

A Foreign Office spokesman said: “We are in contact with the local authorities regarding a group who have been prevented from leaving Gambella airport, Ethiopia.”

Where am I? I keep getting lost … I wanted to go via Gibraltar and just keep the sea on my right to Table mountain Maurice Kirk

Friends and relatives of those involved, who are from around 10 nations, have been trying to help. Terri Tolmack, a Californian businesswoman whose brother Keith is flying a Travel Air 2000 biplane, told the Guardian: “VAR reps told me that everyone has been detained, and that all cell phones and computers were confiscated. All of the embassies are working on a resolve right now.”

On Facebook, Terry Holloway, a British businessman and aviator, said: “The word from Nairobi is that the whole rally has been detained in Ethiopia, and that phones and computers confiscated, etc. One of the pilots apparently managed to call his wife in Europe before being cut off. It looks like it’s all going pear-shaped.”

The project is an extraordinary one. Husband-and-wife teams, fathers and daughters and entire families are attempting to fly more than 8,000 miles across Africa in old aircraft that were designed for short-haul flights.

They are aiming to cross 10 countries, including some beset by war, in a rally seeking to recreate the 1931 Imperial Airways “Africa Route”. The intended route takes in Cairo, the highlands of Ethiopia, Mount Kilimanjaro, the island of Zanzibar and the Victoria Falls, before ending in Cape Town, South Africa, on 17 December.

Two helicopters and six modern aircraft carrying spares and equipment are flying alongside the vintage planes. Special fuel has been flown in to various points along the route.

Facebook Twitter Pinterest Vintage Air Rally biplanes at Sitia, Crete, on 12 November. Photograph: Beatrice de Smet/Vintage Air Rally

Kirk is used to being in trouble. As long ago as 1979, he got into hot water after dropping in on a hang-gliding rally in Wiltshire in a wooden biplane. When his plane was examined, it was found to be riddled with woodworm and had a bird’s nest in one wing.

Even before his disappearance, this trip was not plain sailing. He almost crashed in France when he suffered an engine failure as he approached Cannes. “That so easily could have ended in a tangled pile of twisted aircraft and Maurice,” he said on Facebook.

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On 19 November, he posted: “Where am I? I keep getting lost which is why I really wanted to go via Gibraltar and just keep the sea on my right to Table mountain.” He has suffered a puncture and propeller failure.

Kirk did not set off with the main party but joined them en route. He was then asked to withdraw from the rally because of what the organisers called a “mismatch in expectations”. They were also concerned about the state of his plane.

He has also clearly had some great times en route. He said Dongola in Sudan “will always be a memory of what life is really all about … the fried fish fresh out of the Nile … the coffee you can your spoon up in!”

In his final posting before he vanished, he wrote: “Oh what a night at the British embassy, and access to real beer! I had the Russian ambassidor [sic] particularly interested in the state of our UK law courts and the greed behind it all.”