WASHINGTON — The US Air Force F-16D fleet is nearly back up and flying after a cockpit crack grounded the jets last year, with minimal disruption to pilot training.
The Air Force grounded 82 F-16D fighters last August following the discovery of "canopy sill longeron cracks" found between the front and rear pilot seats — part of the frame of the aircraft that surrounds the cockpit area of the jet. When the canopy is lowered, it rests on the longeron.
The F-16D is a twin-seat variant, often used for training pilots. The Air Force has 157 F-16Ds in its inventory, including Air Education & Training Command (AETC), the Air National Guard (ANG) and Air Force Reserve Command (ARFC).
When the cracks were discovered, officials were concerned that a major invasive procedure would be needed to repair the damage. Instead, Air Force experts and engineers from Lockheed Martin, the prime contractor on the jet, found a solution involving the attachment of steel and aluminum straps to the front fuselage area.
A Lockheed spokesman said repairs have been ongoing and the last three jets should be fully repaired within weeks.
"The US Air Force and Lockheed Martin analyzed the F-16D longeron cracks issue late last year and developed repair procedures for the affected aircraft," Lockheed spokesman John Losinger told Defense News. "Canopy sill longeron repairs should be completed on all 82 USAF/ANG/ARFC F-16Ds this month."
The largest collection of cracked jets was with AETC, where 60 F-16Ds were grounded. A spokesman for AETC said all the jest have been repaired, with most back flying by mid-January.
When the cracks were first discovered, there was concern in Air Education and Training Command (AETC) that flight training for F-16 pilots could be delayed 8 to 12 weeks. However, the spokesman, 1st Lt. Jose Davis, said the training impact "was not as severe as originally forecasted."
"Through the collaborative effort between operations and maintenance personnel from affected active duty, Air Force Reserve Command, and Air National Guard F-16 units, AETC was able to mitigate associated impact on training," Davis wrote in an email. "Those efforts encompassed the development of a revised initial qualification/requalification syllabi using resources available to include loaner aircraft from the Reserve and National Guard, training syllabi waivers, and timely and efficient repair processes by the System Program Office."
As a result of the cracks, the Air Force recommended that international partners who fly the F-16B dual-cockpit design inspect their fleets.
However, neither the US Air Force nor Lockheed appear to keep track of which countries found cracks in their jets and how many have been repaired. Turkey, Israel, Belgium, the Netherlands, Pakistan, Denmark and Norway are among operators of the F-16B.