1991 Gulf War Boeing KC-135 accident. On February 6, 1991, a USAF Boeing KC-135 military aircraft, operating as U.S. Air Force Flight WHALE 05, took off from Prince Abdullah Air Base, Jeddah, Saudi Arabia, while en route on a Gulf War refueling mission. the aircraft lost engines 1 and 2 while flying over the Saudi Arabian desert and to counteract the plane's descent, the pilots began to dump fuel from the aircraft. During the landing in Jeddah, due to the damage of the engines to the hydraulic system, most of the descent was done without autopilot. The aircraft, not having thrust reversers, overshot the landing strip, and finally the four occupants on board landed safely at the air base.

Background

Aircraft 
The aircraft involved was a Boeing KC-135E, it was manufactured by Boeing in 1959 with serial number 17758. It was powered by four Pratt & Whitney TF33-PW-102 engines.

Crew 
The crew consisted of:
 Aircraft Commander Lieutenant Colonel Kevin Sweeney
 Pilot Greg Mermis
 Navigator Steve Stucky
 Boom Operator Jay Selanders

Accident 
WHALE 05 was scheduled for take off from Jeddah at 17:24 local time and climb to 25,000 feet (7,600 m) for aerial refueling. Another Boeing KC-135 took off at around the same time and was supposed to fly the same route. The co-pilot, who was the pilot-in-command, ascended to the planned altitude of 25,000 feet (7,600 m). After climbing, autopilot was engaged, and the aircraft was about one nautical mile behind the other KC-135. 

Approximately 45 minutes after takeoff, WHALE 05 encountered forward wake turbulence and suddenly banked more than 90 degrees to the left, and within a few seconds it banked more than 90 degrees to the right. The captain activated the speed brakes and restored the aircraft to a near horizontal position. During the sequence of events, the first and second left wing engines detached from the left wing. After recovery, fire alarms on the two left side engines were activated. The captain ordered the boom operator to look at the engines, who reported that there was no fire but that the engines were gone. As the aircraft had only been airborn for a short time, it still held almost 31,000 gallons of fuel. In addition, the hydraulic reception, fuel pumps, and landing gear were damaged when the engines fell, and fuel was spilling from the left wing.

To maintain altitude and the speed of fuel discharge, the captain declared "Mayday" and decided to return to Jeddah. The aircraft returned to level flight at 16,000 feet (4,900 m). The pilot soon arrived at Price Abdullah Air Base one hour and 15 minutes later. Since the hydraulic system had been damaged, the landing gear was deployed manually. The pilots requested to land on runway 34L because it was the longest runway and had an instrument landing system (ILS) approach. Upon landing, the pilot deployed a third engine thrust reverser, but immediately discontinued its use due to difficulty in directional control. Although several tires were damaged, the aircraft landed and came to a stop at about 300 m (1,000 ft) from the end of the runway.

Investigation 

At first, speculation made it that since it was a tanker plane in the Gulf War, it was thought to be intentional, although that did not make sense with what was found with the wing and engines of the plane that were recovered. The plane's thrust reversers were in place, so it was thought that this had removed them from the plane, although this was not the case. The plane had turned 110 degrees to the right and then to the left very quickly, it was discovered that another KC-135 was a few miles away, which led to the discovery that it was a powerful wake turbulence producing heavy G forces that caused the accident, although he did not regret not taking one more turn, since this could have caused the two right engines to also come off.

The second plane, taking off before the first, had changed the designated order. The wake turbulence of the second plane when passing it caused the G forces to move the plane with oscillation, making it stable again thanks to the coordination of the team and the skill of the captain. The pilots and crew were credited for knowing what to do in the situation. The Boeing KC-135 was later repaired and returned to military service, being able to fly for another 13 years. It is currently stored at the 309th Aerospace Maintenance and Regeneration Group.

Dramatization 
The accident was featured in the seventh episode of the twenty-first season of the Canadian show Mayday: Air Disasters, titled "Mission Disaster."

See also 

 Trans-Air Service Flight 671 - A Boeing 707 that suffered a dual engine separation on 31 March 1992, landing safely, a year after this accident.
 China Airlines Flight 358 - On 29 December 1991, this Boeing 747 experienced a dual engine separation, killing all five crew members, in the same year of this accident.
 El Al Flight 1862 -  On 4 October 1992, 47 people were killed when the flight suffered a duel engine separation, leading to a loss of control and accident, killing all 4 crew and 43 people on the ground.

References 

Aviation accidents and incidents involving the Boeing KC-135 Stratotanker
Aviation accidents and incidents in 1991
Gulf War
1991 in Saudi Arabia
Aviation accidents and incidents caused by in-flight structural failure
Aviation accidents and incidents involving in-flight engine separations