1968 Geneva Airport DC-8 Jet Blast Incident (N8548Y)

Incident Overview On 23 January 1968 at 1305 HEC, a Douglas DC-8-53 registered HB-IDD, operated by Swissair, was taxiing at Geneva Airport before scheduled flight SR 120 to New York. The aircraft had departed its parking position and was moving toward the runway when the captain requested a change in taxi route. ## Sequence of Events After leaving parking position No. 1, the DC-8 turned left and stopped near an area marked A on the report’s annex. The captain judged that the space between construction work and parked aircraft was too narrow for the DC-8 and contacted the control tower, which authorized runway 05. The DC-8 was stationary with its main-gear wheels in a channel and its nose wheels against a ridge of hardened snow. To move and turn left, the captain advanced the engines to about 80 percent of maximum rpm. The resulting jet blast lifted the nearby parked Luscombe HB-DUS and carried it into the Piper Twin Comanche N-8548-Y. ## Aircraft and Damage The DC-8 was a four-engine Pratt & Whitney JT3D-3B aircraft with a wingspan of 43.4 m and a maximum takeoff weight of about 142 tonnes; its weight at Geneva was about 126 tonnes. The Luscombe HB-DUS was a privately owned high-wing single-engine aircraft weighing about 350 kg. The Twin Comanche N-8548-Y was owned by Piper Aircraft International, Geneva, and was a low-wing twin-engine aircraft weighing about 1,200 kg. The Luscombe sustained damage to its wingtips, empennage, and fuselage, with repair estimated at about Fr. 5,000. The Twin Comanche sustained damage to its left propeller, left engine cowl, and left wing, with repair estimated at about Fr. 10,000. No persons were injured, and no ground damage was reported. ## Investigation Findings The DC-8 captain held a valid airline pilot license and had about 10,000 flight hours, including 3,600 on the DC-8. All three aircraft were regularly admitted to air navigation. The report stated that the parking of the three aircraft complied with applicable rules, and the Luscombe had wheel chocks. The accident occurred on the apron in front of the Grand Hangar, southeast of runway 05’s threshold, where hardened snow remained. Weather was not a factor. The report noted that the captain’s decision not to continue toward the northeast part of the apron was prudent because of obstacles, but that when he decided to head west he was closer to the parked aircraft than if he had originally proceeded to runway 05’s threshold. Relatively high thrust was needed because snow residue slowed the nose wheels and the main-gear wheels were in a channel. ## Probable Cause The accident occurred because the DC-8 captain changed his taxi route while near unsecured light aircraft and had to perform the maneuver with considerable power.