ROBINS AIR FORCE BASE, Ga. —

In 2007 an F-15 split apart in the skies over Missouri. The investigation determined a cracked longeron was the cause of accident. Since that time, the 402nd Aircraft Maintenance Group F-15 Sustainment Programs Office with the Warner Robins Air Logistics Complex at Robins Air Force Base, Georgia, has been inspecting and replacing the longerons to keep our pilots safe and the F-15 C/D Eagle aircraft flying.

“A longeron is the load bearing portion of the aircraft,” said Kahn Wahl, 561st Aircraft Maintenance Squadron flight chief. “They run lengthwise in the structure; and, together with stringers, they form the longitudinal frame for the wings and fuselage that is an integral part of the F-15’s structure.”

With possible loss of aircraft and life, the F-15’s were inspected.

“The longerons had the beginning signs of fatigue and cracking,” said Wahl “An in-depth review of what is absolutely necessary to keep the C/D model safe was decided. The Longeron Replacement Program will focus only on the six longerons and the number one stringer.”

According to Wahl, these components were chosen because a failed longeron is catastrophic and a stringer one failure could hinder pilot ejection.

All the Air Force F-15 C/D models will have to have the longerons replaced.

“There are currently eight aircraft grounded at Robins awaiting LRP,” he said, “and another 15 across the fleet that are grounded or flying on a waiver to receive the modification.”

The 402nd AMXG, F-15 SPO determined it would take 90 days to complete the work for each aircraft.

Wahl said, the plan is for F-15 program depot maintenance to modify the remainder of the F-15 C/D model fleet by 2024.

The 561st AMXS and 558th AMXS are both working together to complete the F-15 C/D LRP.

Wahl said, “The team work has been outstanding. The knowledge and expertise is growing at a fast rate, and there are no obstacles this team cannot overcome.”

The LRP and PDM’s being performed by the members of the 402nd AXMG will provide cost savings to the Air Force.

According to Wahl, it will sustain the number of flight worthy aircraft available to the Air Force and warfighter for additional 20 years and, most importantly, protect human life.

“Having flight-worthy aircraft helps the Air Force pilots train and deploy,” Wahl said. “This is what we do and will do better than anyone else”