Canadair Challenger (N619TS)

1981 Challenger 600 seen here in Aerolineas Ejecutivas (ALE) FBO in Toluca, México. One of the first 23 Challengers built for FedEx, intended to be cargo haulers and distinguished by with the cargo door (opens upward, instead of downward, and the stair has to be manually extended and retracted) but after the FAA de-regulated commercial airliners for cargo, FedEx cancelled the order and Canadair got stuck with a mid-size BizJet.