The V-22 Osprey tiltrotor aircraft underwent climatic testing at the McKinley Climatic Laboratory, Eglin Air Force Base, Florida in 1992. The combination of a revolutionary aircraft configuration and a specialized test facility required the development of new test techniques. The installation of the V-22 in the facility, test operations and results, instrumentation, and data acquisition and processing are described. The results of the climatic testing provided information for the Engineering and Manufacturing Development phase of the V-22 program. The presentation concludes with lessons learned from the V-22 climatic testing that are applicable to climatic testing of the F-35B Lightning II.