The Air Force retired its oldest CV-22 Osprey this week, announced Air Force Special Operations Command. The aircraft—tail No. 99021—served as an additional test asset for the 413th Flight Test Squadron at Eglin AFB, Fla., since 1999. “It’s a one-of-a-kind aircraft,” said MSgt. Joseph Levine, 413th FLTS evaluator flight engineer. “Everything you see on the operational CV-22s has gone through this aircraft first.” The CV-22 fleet and the test aircraft began to have widening differences due to changes in logistics and technology and it “finally progressed to the point [where] we can no longer modify ATA for effective CV-22 testing,” said Levine. The Osprey flew its last sortie on Oct. 31 and it will go on display at the National Museum of the US Air Force at Wright-Patterson AFB, Ohio, states the release. The 413th FLTS will now use operational Ospreys assigned to Hurlburt Field, Fla., to test new equipment, states the Nov. 5 release.