February 9, 2012: U.S. Department of Defense officials have admitted that the daring decision to start production of the new F-35 fighter before testing was completed proved to be a failure. That's because testing revealed more design problems than anticipated. As a result, it's quite likely that very expensive modifications will be needed for F-35s that have entered service. The air force has already ordered 58 F-35s to be produced before all testing is completed and planned to produce 472 F-35s this way. The Department of Defense is more concerned about the additional costs than the air force, which just wants to get the aircraft into production as quickly as possible. The air force fears that the production orders will be cut even further if the F-35 does not enter service quickly. This haste is in part due to the aging of the F-16s the F-35 is to replace. Many of these elderly fighters will soon be too old for training or combat.
To solve this problem, the air force is refurbishing several hundred of its 22 ton F-16 fighters. The F-35 began development in the 1990s and was supposed to enter service in 2011. That has since slipped to 2017, or the end of the decade, depending on who you believe. Whichever date proves accurate the air force has a problem. The average age of existing F-16s is over 20 years and the average aircraft has over 5,000 flight hours on it. Three years ago the first Block 40 F-16 passed 7,000 hours. Four years ago the first of the earliest models (a Block 25) F-16 passed 7,000 hours.
Depending on how late the F-35 is the air force will refurbish 300-600 Block 40 and 50 aircraft. The work will concentrate on extending the life of the airframe, plus some electronics upgrades. The air force does this sort of thing frequently to all aircraft models. It's called SLEP (Service Life Extension Program), and this one is special only because it concentrates on very old aircraft and is intended to keep these birds viable for another 5-10 years. By then, there should be enough F-35s in service to replace the older aircraft. If not, there will be more SLEPing to keep the air force in business.