A British light aircraft pilot was missing in Africa last night after disappearing during vintage plane race.
Retired vet Maurice Kirk, 72, from Taunton, Somerset, disappeared between Sudan and Ethiopia.
Attempts to contact him by radio failed and organisers of the Vintage Air Rally said his family have been notified.
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Kirk, a former drinking pal of the late actor Oliver Reid, was attempting to fly from Crete to Cape Town in a 1943 Piper Cub plane.
The alarm was raised when he failed to arrive at his destination in Gambella in Ethiopia after taking off yesterday from Khartoum in Sudan.
Organisers had earlier asked him to pull out of the race after he suffered engine failure on Sunday.
He was forced to make an emergency landing and though shaken up he said he planned to continue.
A post on the Facebook page of the rally organisers said last night: "Vintage Air Rally participant Maurice Kirk, with his 1943 Piper Cub aeroplane, has not arrived at his expected destination, Gambella, Ethiopia.
"Contrary to our advice to return to Khartoum, Mr. Kirk, 72, departed Ad-Damazin, Sudan at approximately 1400 local time (1100 GMT) on the three-hour flight to Gambella.
"No radio communications or satellite tracking were received at any time during the flight, and his location is unknown.
"Mr. Kirk is a very experienced pilot, and so it is believed that he has made a precautionary landing before sunset, somewhere in Ethiopia.
"The Ethiopian authorities, and his family, have been informed and search and rescue procedures will begin at first light."
After his emergency landing on Sunday Kirk, whose nickname is 'Capatain Kirk', said the experience left him "badly shaken".
He said: "Normally I would have taken this kind of event in my stride, but as I get older in years, even a minor incident like this one has shaken me up.
"But it won't wont stop me. It could be one of my last great adventures and I'm going to keep going."
He is taking part in the 8,000-mile trans Africa vintage plane rally with 14 other single-engined vintage planes.
The rally, which is being sponsored by Puma Energy, will raise money for UNICEF and Bird Life International and will attempt to cross the continent at low altitude.The race has been organised by Sam Rutherford, a former helicopter pilot in the Army Air Corps, who now runs a logistics company Preapre2go.
The teams will cross 10 countries, many beset by war and borderline famine, in a rally that will seek to recreate the 1931 Imperial Airways "Africa Route".
From Cairo, the first stop, the pilots have already flown over the Nile to Khartoum. Two helicopters and six modern aircraft, carrying spares and equipment, are flying alongside.Special fuel has been flown in to points along the route.
Kirk's narrow escape on Sunday was the latest in a series of mishaps for the pilot.
The flyer, who was once Oliver Reid's vet, was rescued after ditching in the Caribbean in an attempt to fly solo around the world in a 65-year-old plane in 2008.
He was found 75miles from the Dominican Republic by US coastguards who tracked his 'life-saving' radio beacon.
And two months later he was arrested by Texas cops after landing near former president George Bush's ranch.
Dad-of-four Mr Kirk said he wanted to thank the president for the way US coastguards rescued him after his World War Two plane ditched in the shark-infested Caribbean in February.