The original program called for two test airframes, five flyable aircraft, and 40 engines. Both were employed making aero engines and airframes. Two of the original 747-200 airframes were originally planned to be commercial airliners. The work included overhaul of the airframes and systems, including propellers and engines. These incomplete airframes were eventually scrapped. The first 76 aircraft entered service by 2008, with a total of 98 airframes produced. Wargames had indicated that severe attrition to airframes and hulls would occur in any war. The engines and airframes in particular had low service lives. Production of parts to build the prototype and test airframes began in July 2000. Several of the airframes were retained by Junkers for further development. The Cuban Air Force took delivery of 29 ex-USAF airframes and spares. The D-2 was a variant used as a glider tug by converting older D-series airframes. Museum quality restoration to flying condition completed at Latrobe Valley Airframes and Welding, Victoria Australia. E models were conversions from existing CH-47C model airframes. Thailand was the last remaining government using first generation Harrier airframes.