N421AG

HISTORY OF FLIGHT

On June 15, 1994, about 1434 hours Pacific daylight time, a Cessna 421C, N421AG, crashed during a forced landing, about 1 1/2 miles northeast of the McClellan-Palomar Airport, Carlsbad, California. The airplane was being operated as a visual flight rules (VFR) cross-country business flight to Las Vegas, Nevada, when the accident occurred. The airplane, operated by the pilot, was destroyed. The certificated commercial pilot and one pilot-rated passenger received fatal injuries. A second passenger received serious injuries. Visual meteorological conditions prevailed. The flight originated at the McClellan-Palomar airport about 1431 hours.

A Federal Aviation Administration (FAA) air traffic controller at the McClellan-Palomar airport reported that he was working the local control position and cleared the pilot for takeoff. The takeoff roll and rotation appeared normal. About 2 minutes after departure, the controller again noticed the aircraft on a right downwind and it appeared lower than the standard pattern altitude and appeared slower than normal with a slight nose up attitude. About midfield, the pilot made a radio call and stated: "...palomar golden eagle...(unintelligible)...return for landing, i've just lost an engine." The controller cleared the airplane to land on runway 24. There was no further communication from the pilot.

The airplane appeared to make a gentle right turn about 1,000 to 1,500 feet above the ground, and began a gradual descent. The landing gear appeared up and the controller observed the airplane for about 35 seconds. The pilot turned toward the airport and the airplane was observed to descend into rolling brush covered terrain northeast of the airport.

The surviving passenger reported that while he was seated in an aft-facing seat, he heard the pilot declare an emergency; however, he did not recall any dramatic engine problems. He indicated that he felt some type of bump and heard some sort of a "bang" sound. The airplane began descending and he heard a beeping sound from the cockpit that continued throughout the descent to impact. He described the sound as similar to that when the altitude alert tone sounded on previous flights. The airplane did not yaw adversely one direction or the other and he did not recall hearing any obvious change in the pitch or synchronization of the sound of the engines.

The accident occurred during the hours of daylight at latitude 33 degrees 08.56 minutes north and longitude 117 degrees 15.10 minutes west.

CREW INFORMATION

The pilot held a commercial pilot certificate with airplane single-engine land, airplane single-engine sea, airplane multiengine land, instrument airplane, and rotorcraft helicopter ratings. The most recent second-class medical certificate was issued to the pilot on March 1, 1994, and contained the restriction that his medical certificate was not valid for night flying or by color signal control.

According to the pilot's logbook, his total aeronautical experience consisted of about 3,340.2 hours, of which 1,240.2 were accrued in multiengine aircraft. In the preceding 90 and 30 days prior to the accident, the logbook lists a total of 58.6 and 22.6 hours respectively flown.

AIRCRAFT INFORMATION

The aircraft had accumulated a total time in service of 2,943.2 flight hours. Examination of the maintenance records revealed that the most recent annual inspection was accomplished on September 13, 1993, 98.1 flight hours before the accident. The airplane had received an oil change on both engines prior to the accident flight and, in addition, all of the spark plugs on the left engine were replaced. The recording hobbs meter indicated that 1.5 hours had elapsed from the oil change to the accident. The engines had accrued 2,943.2 hours of operation. A major overhaul was accomplished on the left engine on March 11, 1988, 1,140.9 hours of operation before the accident. The right engine received a major overhaul on November 11, 1992, 239.7 hours of operation before the accident.

Fueling records at Gibbs Aviation, Carlsbad airport, established that the aircraft was last fueled before the accident flight with the addition of 116.4 gallons of 100LL octane aviation fuel from truck No. 974 before the truck ran out of fuel. Truck 974 had previously provided fuel to three aircraft before being utilized to fuel the accident airplane. An additional 35 gallons were added from truck No. 971. Truck 971 provided fuel to twelve additional aircraft after fueling the accident airplane. Both fuel trucks were inspected by FAA personnel with no reported discrepancies. The airplane is equipped with fuel filler restrictor collars that preclude fueling from flared style (Jet A) fuel nozzles. Gibbs Aviation personnel reported that their Jet A fuel truck is equipped with flared fuel nozzles. FAA inspectors reported that the Jet A fuel truck was not equipped with flared fuel nozzles.

The fuel supply for both fuel trucks is from a storage tank that last received 9,000 gallons of 100LL on June 6, 1994. On the date of delivery, an American Petroleum Institute (API) specific gravity test, corrected for temperature, indicated 70.7 degrees. Following the accident, Gibbs personnel reported that API specific gravity tests on contents of the storage tank and the fuel trucks 971 and 974, corrected for temperature, were 70.1, 71.1, and 70.5 degrees, respectively.

According to the engine service manual, fuel lines from the fuel manifold carry metered fuel to each cylinder's fuel discharge nozzles. An air bleed and nozzle pressurization system consisting of tubes and sleeve fittings provides pressurized air around the fuel nozzle. The pressurized air (upper deck air) is supplied by turbocharger discharge air and aids in vaporization of the fuel.

The aircraft is equipped with auxiliary fuel pumps that have OFF, LOW, and HIGH settings. The switches are a toggle-type, lever lock design that prevents the HIGH setting from being selected unless the switch is pulled up and over a locking detent. The aircraft's flight manual supplement pertaining to the operation of the three-position switch indicted that the LOW position can be used, when required, to provide supplementary fuel pressure for all normal operations. The HIGH position is reserved for emergency operation to sustain partial engine power in the event on an engine-driven fuel pump failure. The flight manual contains a caution that states: "...If the auxiliary fuel pump switches are placed in the HIGH position with the engine-driven fuel pump(s) operating normally, total loss of engine power may occur."

The aircraft flight manual indicated that the airplane has a single-engine rate of climb of 350 feet per minute. The flight manual also contains a warning that states:"...The propeller on the inoperative engine must be feathered, landing gear retracted and wing flaps up or continued flight may be impossible."

METEOROLOGICAL INFORMATION

The closest official weather observation station is the McClellen-Palomar airport, which is located 1 1/2 nautical miles southwest of the accident site. At 1434 hours, a surface observation was reporting in part: Sky condition and ceiling, scattered clouds at 1,800 feet, estimated ceiling, 3,000 feet broken; visibility, 30 miles; wind, 210 degrees at 10 knots; altimeter, 29.97 inHg.

AERODROME AND GROUND FACILITIES

The McClellan-Palomar airport has a published elevation of 328 feet mean sea level. The airport is equipped with one hard- surfaced runway oriented on 060/240 degrees. Runway 24 is 4,700 feet long by 150 feet wide.

WRECKAGE AND IMPACT INFORMATION

National Transportation Safety Board investigators examined the airplane wreckage at the accident site on June 16 and June 17, 1994. A subsequent examination of the wreckage occurred on June 23, 1994, after the airplane was recovered to Ramona, California. Ground scars and wreckage debris were oriented on about a 100 degrees heading on about eight degree upsloping brush-covered terrain. About 120 feet after initial ground contact, the nose of the airplane struck a 20-foot-high, 45-degree upsloping ridgeline. The airplane came to rest on top of the ridgeline with the nose of the airplane oriented on about a 180-degree heading. (All heading/bearings noted in this report are oriented toward magnetic north.)

All of the airplane's major components were found at the main wreckage area. The nose and baggage compartment of the airplane were crushed and folded in an aft direction. Upward crushing of the bottom of the aircraft was evident from the nose to the instrument panel. The radar antenna separated from the airplane and was located about 20 feet forward of the fuselage.

The cockpit floor was crushed upward to the rudder pedals. The lower left side of the instrument panel was crushed and bent in a forward direction. The right side of the panel was similarly bent forward. The instrument panel glare shield was crushed downward over the top of the panel. Both of the control yokes were removed by rescue personnel by cutting of the control columns near the instrument panel. The entire windshield and overhead roof of the cockpit was removed by rescue personnel. The right wing exhibited minor leading edge aft crushing about 2 feet inboard from the tip with chordwise scratching along the underside of the wing. The left wing displayed minor leading edge wrinkling and aft crushing of the leading edge at the outboard tip. The underside of both wings and fuselage exhibited upward crushing and buckling.

The flight control surfaces remained connected to their respective attach points and flight control system cable continuity was established. The landing gear was retracted. The manufacturer reported that the flap chain travel corresponded to about a 30-degree flap setting.

The tail assembly separated from the fuselage at the rear pressure bulkhead and was only attache...