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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 .
MD 11
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