in 1989, twa decided to replace its fleet of boeing 727 series 100 aircraft with the former ozark airlines dc-9s. this decision was based on the economics of operating three-crew airplanes (727s) with three engines, versus operating two-crew airplanes (dc-9s) with two engines. both airplanes had about the same passenger and cargo capacity, so it was decided to replace the boeing fleet. to prepare for this transition, twa positioned several million dollars worth of spare parts for the dc-9s in germany. this was a requirement dictated by the german government. if twa wanted to use dc-9s in the service of the german population, then twa had to provide readily available spare parts for its fleet. the airline also sent its senior dc-9 pilots (known as check airmen) to europe to observe the operations in preparation for the changeover of the crews that was to follow. shortly before the dc-9 airplanes began arriving in germany, however, the entire plan was cancelled because the leasing contracts that carl icahn had created for the former ozark dc-9s specifically forbade any operations outside the continental limits of the united states.