Wear and Tear

The Air Force’s F-16 Block 40/42 aircraft are experiencing cracked bulkheads that require repair or eventual replacement. While not a safety-of-flight concern, this issue, like the F-15 longeron saga, epitomizes the challenges of operating platforms for longer than their intended services lives while having to fly them at high tempo rates through 17 years of continual overseas deployments and wars. Already 63 of USAF’s 397 F-16 Block 40/42s have been identified as having the cracks. Four F-16s were grounded initially and had their bulkheads replaced, officials at Hill AFB, Utah, told the Daily Report. The other 59 airframes have no flight restrictions imposed on them, but are being inspected every 10 flight hours to monitor the situation. USAF and Lockheed Martin, the F-16’s manufacturer, have a repair design in place that will be installed starting in May as a permanent fix for aircraft with very minor cracks. For those airframes with more pronounced cracks, the repair would only be a temporary fix, so USAF and Lockheed Martin have developed a new bulkhead that can withstand additional stresses. Installation of the repair design should be complete for all known cases by January 2009, while bulkhead replacements will continue through December 2009, the Hill officials said. By staying vigilant in monitoring the bulkheads, USAF hopes to catch future cracking early enough so that the repair will suffice and greatly reduce the need for replacing bulkheads. This point is critical since newer F-16 Block 50/52s have the same bulkhead design as the F-16 Block 40/42s and will be affected at some point in their service life with the cracks due to structural fatigue, according to the Hill officials. (For more read 341 Bulkhead)