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It was during this period that flaws in the MD-11 ' s performance became apparent. It failed to meet its targets for range and fuel burn. American Airlines in particular was unimpressed with the 19 MD-11s that it received, as was Singapore Airlines who canceled their order for 20 MD-11s and instead ordered ordered 20 Airbus A340-300s. American Airlines cited problems with the performance of the airframe and the Pratt & Whitney PW4000 engines, while Singapore Airlines stated that the MD-11 could not operate on the airline ' s long haul routes.
Pre-flight estimates indicated that the P & W-powered MD-11 was to have a 7,000 nautical miles( 13,000 km) range with 61,000 pounds( 28,000 kg) of payload. With the Phase 1 drag reduction in place then, the aircraft could only achieve its full range with 48,500 pounds( 22,000 kg) of payload, or a reduced range of 6,493 nautical miles( 12,025 km) with a full payload.
With the Phase 1 drag reduction in place then, the aircraft could only achieve its full range with 48,500 pounds( 22,000 kg) of payload, or a reduced range of 6,493 nautical miles( 12,025 km) with a full payload. In 1990, McDonnell Douglas, along with Pratt & Whitney and General Electric began a modification program known as the Performance Improvement Program( PIP) to improve the aircraft ' s weight, fuel capacity, engine performance and aerodynamics. McDonnell Douglas worked with NASA ' s Langley Research Center to study aerodynamic improvements. The PIP lasted until 1995 and recovered the range for the aircraft. However, by this point sales of the MD-11 had already been significantly impacted. In 1995, American Airlines sold their 19 MD-11s to FedEx, as the PIP program was not sufficient for the aircraft to fly the Dallas-Hong Kong route.
After McDonnell Douglas merged with Boeing in 1997 the new company decided that MD-11 production would continue, though only for the freighter variant. In 1998, Boeing announced they would end MD-11 production after filling orders on hand.
The last passenger MD-11 built was delivered to Sabena in April 1998.
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