DEN99LA070

The pilot said that the takeoff was uneventful, and he began to level off at 1,000 feet agl to stay in the traffic pattern. He reduced the manifold pressure and began to lean the fuel mixture for cruise with the aid of the engine analyzer. After several communications with the tower, he turned the vernier mixture control further in the lean direction. The pilot said that the engine completely lost power without warning. The passenger stated that the engine fuel flow gauge 'was not indicating any fuel flow,' and the fuel mixture control was in the idle cut-off position. The pilot turned on the auxiliary fuel pump for an engine restart, but didn't move the mixture. The pilot performed a forced landing to 2 to 4 foot sand dune covered terrain. The manufacturer expanded the emergency procedure checklist, in later model T210's, to include 'mixture lean from full rich until restart occurs.' The pilot had 15 hours of flight experience in the airplane, and he had not flown it in the previous 90 days. The engine was placed on a engine run test stand, and it performed normally through its full operating range without difficulty.

On April 30, 1999, at 1313 mountain daylight time, a Cessna T210L, N59235, was destroyed during a forced landing after takeoff from Albuquerque International Airport, Albuquerque, New Mexico. The commercial pilot and his passenger received minor injuries. The airplane was being operated by the Kirtland Air Force Base Aero Club, Albuquerque, New Mexico, under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the local maintenance test flight which originated 3 minutes prior to the accident. No flight plan had been filed.

The pilot said that the purpose of the flight was to perform a post maintenance evaluation of the airplane. The passenger in the right front seat was the chief mechanic and he was riding along to document the performance results. The pilot reported that the takeoff on runway 17 was uneventful, and that he leveled off at 1,000 feet above ground level (agl) to stay in the traffic pattern. He reduced manifold pressure and began to lean the fuel mixture for cruise with the aid of the GEM 603 engine analyzer. The pilot stated that the number 2 column on the GEM 603 began to blink, indicating that the number 2 cylinder had reached peak exhaust gas temperature (EGT). The pilot then had several communication exchanges with the control tower, and he began turning the airplane northbound for a traffic pattern downwind. He put his hand back on the vernier mixture control with the intention of enriching the fuel mixture, but "rotated the mixture control one and a half turns in the lean direction instead." The pilot said that the engine "completely lost power without warning." The passenger stated that the engine fuel flow gauge "was not indicating any fuel flow," and that the fuel mixture control lever was "in the idle cut-off position."

The pilot said that he "attempted an engine restart as the manual states while looking for a place to make a forced landing." The passenger stated that the pilot turned on the auxiliary fuel pump switch, but didn't move the engine mixture control forward. The passenger further stated that he pointed to the mixture control and said to the pilot, "it's all the way out!" The pilot said that he made an intentional gear up landing due to the rough terrain (2 to 4 foot high sand dunes).

The Cessna T210L Pilot's Checklist for Engine Failure During Flight states the following:

A. Airspeed-100 MPH; B. Fuel Selector Valve and Quantity-CHECK; C. Mixture-RICH; Auxiliary Fuel Pump-ON; D. Ignition Switch-BOTH (or START if propeller is stopped).

Cessna expanded this Emergency Procedures checklist in later model T210's (with the same engine) to include:

1. Airspeed---85 KIAS, 2. Auxiliary Fuel Pump---ON, 3. Fuel Selector Valve---OPPOSITE TANK (if it contains fuel), 4. Throttle---HALF OPEN, 5. Auxiliary Fuel Pump---OFF 6. Mixture---LEAN from full rich until restart occurs, 7. Mixture---ADJUST as required, 8. Throttle---ADJUST power as required, 9. Fuel Selector Valve---AS DESIRED after fuel flow is stabilized.

Additionally, the Owner's Manual published by the airplane's manufacturer states that leaning procedure is performed by leaning the mixture back to peak exhaust gas temperature (EGT) and enrich the mixture until the EGT is on the rich side of peak by an increment of 100 degrees Fahrenheit.

The pilot indicated on the National Transportation Safety Board's Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2) that he had not flown the Cessna T210L in the previous 90 days, but he had 15.2 hours in the airplane.

The airplane's engine was removed and shipped to the manufacturer for examination. The engine was put on a test stand on December 3, 1999, and ran through its full operating range with no abnormalities noted.

On December 14, 1999, the pilot wrote a letter to the safety investigator at Kirtland Air Force Base saying the following (see attached document): 1. He did enrich the mixture control sufficient to stop the GEM lights from flashing. 2. He did lean the mixture a second time (by an unspecified amount), but not enough, he believes, to cause the engine to quit.

The Investigator-In-Charge telephoned the passenger on December 21, 1999, and was told that this was accurate information, but the mixture was leaned the second time 3 to 3 1/2 inches out to idle cut-off position (see attached document).