fully refuelled the Landshut plane and the pilots started up the engines. At 12:19 on Sunday 16 October it took off, bound for Salalah and Masirah in Oman, where permission to land was once again denied and both airports were blockaded. After Riyadh also closed and blockaded its airport runways at 14:50 on 16 October (three days after the hijacking began), a course was set to Aden in South Yemen, at the limit of the plane's fuel range. Aden Approaching and overflying Aden, the flight was yet again denied permission to land, this time at Aden International Airport, and both main runways (including the apron) were blocked by military jeeps, tanks and other vehicles. The plane was running dangerously low on fuel, but the Aden airport authorities adamantly refused to clear the runways, leaving co-pilot Vietor little choice but to make an emergency landing on an unpaved sand strip roughly parallel to (in-between) both runways. The plane remained largely intact following the ground roll but when the Aden authorities told the hijackers and pilots that they needed to fly away, both pilots were concerned about the aircraft's airworthiness after its rough, hard landing on rugged, rocky and sandy terrain, deeming it unsafe to take off and fly the jetliner again until a thorough engineering inspection had been made. After the engineers claimed that everything was all right with the airframe, Mahmud consequently allowed Schumann to check the condition of the landing gear and the engines. Both engines had ingested a copious amount of sand and dirt at maximum reverse thrust and were clogged up. The landing gear had not collapsed, but its structure was weakened and its extension/retraction mechanism was damaged. Schumann did not immediately return to the plane after inspecting it, even after numerous calls by the hijackers threatening to detonate the aircraft because of his departure. The reasons for his prolonged absence remain unclear to this day. Some news reports, including interviews with Yemeni airport authorities, imply that Schumann was asking ground crews to prevent the flight from taking off and to refuse to accede to the terrorists' demands. Schumann subsequently boarded the plane to face the wrath of Mahmud, who furiously forced him to kneel on the passenger cabin floor before fatally shooting him in the head, without giving him a chance to explain himself. The hijacked plane was refuelled at 01:00 on 17 October and at