Losses and Aviation Safety

Remembering Shell 77, the KC-135 that crashed in Kyrgyzstan while it was departing for combat aerial refueling mission

Shell 77 crew encountered a condition they had not realistically experienced in training, which left them with an unrecognized hazardous situation that was difficult to overcome.

On May 3, 2013, a KC-135R, call sign Shell 77, crashed in the foothills of mountains located six miles south of Chaldovar, Kyrgyz Republic. The Aircraft was assigned to the 22d Air Refueling Wing at McConnell AFB, Kan., and was flown by members of the 92d Air Refueling Wing at Fairchild AFB, WA. The crew was flying out of the 376th Air Expeditionary Wing at the Transit Center at Manas.

Cockpit section of KC-135R wreckage.

The crew was departing from the Transit Center at Manas to Afghanistan on a combat aerial refueling mission. The aircraft exploded in flight, impacted the terrain at three main locations, and burned, costing the lives of Capt Mark Tyler Voss, Capt Victoria A. “Tori” Pinckney, and TSgt Herman “Tre” Mackey III.

According to Air Mobility Command (AMC) Accident Investigation Board (AIB), immediately after takeoff, a flight control system malfunction generated directional instability, causing the aircraft’s nose to drift from side-to-side, or “rudder-hunt.” This condition, not fully diagnosed by the crew, progressed into a more dangerous oscillatory instability known as “Dutch roll.”

KC-135R Horizontal stabilizer section as found north northeast of main debris field.

The AIB identified that a poor layout of key information in the flight manual and insufficient crew training contributed to the mishap by detracting from the crew’s ability to act on critical information while troubleshooting. The AIB found the crew did not recognize the Dutch roll condition, initiated a left turn to remain on course, and used left rudder to coordinate the turn, thereby increasing the aircraft’s oscillatory instability. The ensuing severe side-to-side movements of the aircraft varied the crew member’s foot pressure on the rudder pedal, which caused inadvertent fluctuations in rudder position. These fluctuations, coupled with right rudder use while rolling out of the turn, compounded the Dutch roll severity and produced extreme airframe stress that caused the KC-135’s tail section to separate from the aircraft. The subsequent, uncontrollable descent resulted in an in-flight explosion.

A combination of factors–flight control malfunctions, insufficient crew force training, incomplete checklist response, use of rudder while in a Dutch roll condition, crew composition, and procedural guidance–all came together during the flight, resulting in this accident. The crew encountered a condition they had not realistically experienced in training, which left them with an unrecognized hazardous situation that was difficult to overcome.

KC-135R Section of rudder as found north northeast of main debris field.

“Our hearts go out to the family members and friends of these Airmen,” said Brig Gen Steve Arquiette, who led the accident investigation board. “Having attended the memorial service at Manas and later interviewing many co-workers, I know these Airmen were highly regarded and are greatly missed. The investigation team, with the help of our industry and Kyrgyz government partners, pushed through months of intense fact finding for the primary purposes of understanding what happened that day and to honor the crew’s service to our nation.”

The AMC way forward was clear–making immediate changes and improvements to checklists, to procedures, and to simulators. Specific actions included revised crew procedures for unscheduled rudder deflection and modifying KC-135 flight simulators and training syllabi to better prepare aircrews for Dutch roll and lateral flight control events. The command was also working with the airplane manufacturer and the AF Lifecycle Management Center to rewrite flight manual sections and conduct in-depth analysis of rudder system components to develop component and T.O. improvements. AMC plans to continue to refine and implement solutions to prevent any repeats of this tragedy and ensure the KC-135 remains a safe, effective, and capable aircraft for many years.

This print is available in multiple sizes from AircraftProfilePrints.com – CLICK HERE TO GET YOURS. KC-135R Stratotanker 161st Air Refueling Wing, 197th Air Refueling Squadron “Copperheads”, 63-8038 – Arizona Air National Guard – Sky Harbor ANG Base, AZ

Photo credit: U.S. Air Force

Artwork courtesy of AircraftProfilePrints.com

Dario Leone

Dario Leone is an aviation, defense and military writer. He is the Founder and Editor of “The Aviation Geek Club” one of the world’s most read military aviation blogs. His writing has appeared in The National Interest and other news media. He has reported from Europe and flown Super Puma and Cougar helicopters with the Swiss Air Force.

Recent Posts

The story of why the German Air Force and German Navy dubbed the F-104 Starfighter “Widow Maker”

The F-104 Starfighter Designed as a supersonic superiority fighter, the F-104 Starfighter was produced in… Read More

32 mins ago

Video shows C-130 Hercules “Buddy Start” (engine start utilising the propeller blast of another aircraft to effect engine starting)

The C-130 Hercules The C-130 Hercules primarily performs the tactical portion of the airlift mission.… Read More

36 mins ago

Legendary F-14 pilot Joe “Hoser” Satrapa tells the story of the gun kill on an F-15 that almost sold Tomcats to Japan

Joe “Hoser” Satrapa No dissertation on present-day section tactics, or on naval aviation in general,… Read More

1 day ago

Marine Infantry Rifleman tells why (except the VH-60 White Hawks flown by HMX-1) the USMC doesn’t use the Black Hawk Multirole Helicopter

The Black Hawk Multirole Helicopter The Black Hawk is the military's most versatile helicopter, suited… Read More

1 day ago

USAF reveals AGM-183A ARRW with live warhead in Guam during hypersonic weapon training

AGM-183A ARRW with live warhead in Guam Andersen Air Force Base (AFB) on Feb. 27,… Read More

2 days ago

Operation Tamouré: the only time a French Air Force Mirage IV strategic bomber dropped a live nuclear bomb

The Mirage IV The Suez crisis in October 1956 prompted France to look into setting… Read More

2 days ago