IT SHOULD NOT HAPPEN TO YOU
COMANCHE ACCIDENTS, 4.2003, AND A CASE
by Omri Talmon
COMANCHE ACCIDENTS, 4.2003
4.1 Date: 04/29/2003. Acft: PA-24-250. Descr: ACFT LANDED GEAR UP ON RUNWAY 24, OTHER CIRCUMSTANCES ARE UNKNOWN. Damage: Minor. One occupant, no injuries.
Accident occurred APR-14-96 at SANTA PAULA, CA. Aircraft: Piper PA-24-250.
Injuries: 2 Uninjured.
The pilot planned to fly from Van Nuys to Santa Paula to purchase fuel at a discount. He indicated that upon takeoff a total of 44 gallons of fuel were in the four fuel tanks. According to the pilot, during the flight no mechanical problems were experienced. Approaching Santa Paula, the engine lost all power, and the pilot made a forced landing. The airplane collided with rough terrain within 1 mile of the runway. Recovery personal picked up the airplane and reported finding between 7 and 8 gallons of fuel upon draining the wings from the fuselage belly sump drain. The engine was subsequently test run, and no discrepancies or malfunctions were observed. According to the Piper Aircraft Corp., the nominal 75 percent engine power fuel consumption rate is about 14 gallons per hour.
fuel starvation due to the pilot's failure to monitor fuel tank quantities and to assure that the fuel tank selector was positioned to a tank containing adequate fuel.
On April 14, 1996, at 1200 hours Pacific daylight time, a Piper PA-24-250, operated by the pilot, experienced a total loss of engine power approaching the Santa Paula Airport, Santa Paula, California. The pilot made a forced landing in rough terrain west of runway 04. The airplane was substantially damaged. Neither the private pilot nor the passenger was injured. Visual meteorological conditions prevailed, and no flight plan was filed. The flight originated from Van Nuys, California, at 1100.
According to the Federal Aviation Administration coordinator (FAA), the purpose of the flight was, in part, to purchase fuel at a discount. During the flight, no mechanical problems with the airplane were reported by the pilot. While turning onto the base leg, between 700 and 800 feet above ground level, the engine suddenly lost power. The pilot made a forced landing and collided with a knoll short of the runway.
Recovery personnel picked up the airplane and transported it to Rays Aircraft, at the Santa Paula Airport. They reported to the FAA that between 7 and 8 gallons of fuel were found upon draining the wings from the fuselage belly sump drain.
In the pilot's completed accident report, he reported having 44 gallons of fuel onboard upon takeoff from the Van Nuys Airport. On April 23, 1996, the National Transportation Safety Board requested that the pilot provide copies of documents showing the quantity of fuel onboard during the accident flight. During a May 9, 1996, telephone conversation with the pilot, the Safety Board was informed that no documents were available.
On May 14, 1996, the engine, with its attached airframe, was secured to a test bed. A temporary fuel supply line was attached, and the engine was started using the starter motor. Due to safety concerns, the engine was only run-up to partial power. According to the FAA certificated mechanic who conducted the test, normal engine temperatures and pressures were developed, and no discrepancies or malfunctions were observed.
According to the Piper Aircraft Corporation, when operating a PA-24-250 Commanche with a Lycoming O-540 engine, the nominal 75 percent power fuel consumption rate is about 14 gallons per hour.
Flown for one hour, the aircraft consumed some 15 gallons of fuel. Added to the 7 to 8 gallons recovered from the aircraft after the accident, it totals 23-24 gallons. The pilot reported having 44 gallons on board before starting. There is a discrepancy here. The NTSB report does not tell us the amount and type of damage so we cannot know if fuel was lost after the accident through a ruptured fuel cell or fuel line.
In any event, at the time of the accident, there was fuel on board, and the fuel starvation is most probably due to mismanagement of the fuel.
As already written a great number of times, Comanches have at least two fuel tanks with no "both" position on the fuel selector, and many of them have four or six tanks, not to mention the exceptions (like Karl Hipp's plane described under Comanches In The 21st Century, which sports ten tanks in the wings and nacelles). All this requires some paperwork and accounting to keep track of the fuel FOR EACH AND EVERY FLIGHT, even the shortest one. It should also be mentioned that the operations manual, practice, and good sense demand that the fullest tank be selected prior to landing. This accident further demonstrates why this is a sensible idea.
There are three of them: Fuel management, fuel management, and fuel management.
Then, let's not forget the landing gear.
Never let an airplane take you somewhere your brain didn't get to five minutes earlier.