Aviation Accident Summaries

Aviation Accident Summary LAX94FA256

LONG BEACH, CA, USA

Aircraft #1

N344FM

FOUGA CM 170

Analysis

A FORMER FRENCH AIRFORCE FOUGA CM 170 JET TRAINER LOST POWER IN BOTH ENGINES AND COLLIDED WITH TERRAIN AFTER TAKEOFF ABOUT 2,000 FEET FROM THE DEPARTURE END OF THE RUNWAY. THE PILOT REPORTED A LANDING GEAR PROBLEM AND REQUESTED CLEARANCE TO RETURN TO THE AIRPORT. WITNESSES REPORTED HEARING THE AIRPLANES'S JET ENGINES 'SPOOL DOWN' DURING THE TAKEOFF CLIMB ABOUT 600 FEET ABOVE THE GROUND (AGL). THE AIRPLANE DESCENDED TO ABOUT 300 FEET AGL WHEN THE LEFT WING DIPPED, FOLLOWED BY THE RIGHT WING DROPPING RAPIDLY. ANOTHER PILOT WHO WITNESSED THE ACCIDENT STATED THE AIRPLANE APPEARED TO STALL. THE AIRPLANE THEN DESCENDED UNCONTROLLED, COLLIDING WITH TERRAIN OFF THE AIRPORT BOUNDARY. THE AIRPLANE HAD BEEN RECENTLY IMPORTED TO THE UNITED STATES DISASSEMBLED AND DEFUELED. THE DESIGN OF THE AIRCRAFT FUEL SYSTEM DOES NOT ACCOMMODATE PREFLIGHT FUEL SAMPLING FROM THE RUBBER BLADDER FUEL CELLS IN THE FUSELAGE. WATER AND SMALL PARTICLES WERE OBSERVED IN A FUEL SAMPLE DRAINED FROM THE FUEL LINES AFTER THE ACCIDENT. THE PILOT'S LANDING GEAR WARNING LIGHT ILLUMINATES ANY TIME ENGINE RPM DROPS BELOW 18,000 RPM AND ANY ONE OF THE THREE LANDING GEAR IS RETRACTED.

Factual Information

On June 15, 1994, at 1457 hours Pacific daylight time, a Fouga CM 170, N344FM, lost power and collided with terrain about 2,000 feet from the departure end of runway 30 at the Long Beach Airport, Long Beach, California. The airplane was being operated by Paradise Aero, Inc., Long Beach, California, as a ferry flight to Porterville, California. The airplane was destroyed by impact forces and postimpact fire. The certificated airline transport pilot and private pilot rated passenger were fatally injured. Visual meteorological conditions prevailed. The airplane was cleared for takeoff on runway 30 by the Long Beach air traffic control tower. After takeoff, the airplane pilot reported a landing gear problem and requested clearance to return to the airport. The airplane was then observed descending until it collided with the ground. Witnesses reported hearing the airplane jet engines "spool down" during the takeoff climb about 600 feet above the ground (agl). The airplane descended to about 300 feet agl when the left wing dipped, followed by the right wing dropping rapidly. One of the witnesses, a pilot, stated the airplane appeared to stall. The airplane then descended uncontrolled colliding with terrain off the airport boundary. CREW INFORMATION FIRST PILOT The first pilot, held an airline pilot certificate which was issued on September 28, 1991, with multiengine airplane ratings and a commercial pilot certificate with a single-engine airplane rating. The first pilot held a flight instructor certificate for single-engine airplanes issued on September 23, 1992. The Federal Aviation Administration (FAA) issued a Letter of Authorization (LOA) on November 22, 1993, allowing the first pilot to act as pilot-in-command of CM-170 Fouga Magister. The most recent first-class medical certificate was issued to the pilot on April 25, 1994, and contained no limitations. According to the first pilot's logbook, his total aeronautical experience consisted of 1,921.7 hours, of which about 81 hours were accrued in the accident airplane make and model. In the preceding 90 days before the accident, the logbook lists a total of 49.3 hours of which 21.6 hours were accrued in the accident airplane make and model. SECOND PILOT The second pilot held a private pilot certificate which was issued on January 21, 1993, with a single-engine airplane rating. The second pilot did not hold an LOA to pilot a Fouga jet. The second pilot held a third-class medical certificate issued on November 13, 1992, and contained the limitation that correcting lenses be worn while exercising the privileges of his airman certificate. According to the second pilot's logbook, his total aeronautical experience consists of about 75.5 hours, all in single-engine airplanes. The National Transportation Safety Board could not determine the reason the second pilot was being carried aboard the aircraft. AIRCRAFT INFORMATION The Fouga Magister CM 170 is an all metal, twin-engine tandem-seated military trainer. The airplane is powered by two Turbomeca Marbore II turbojet engines rated at 880 pounds of thrust each. The airplane is manufactured in France and was primarily used by the French Air Force. The airplane was imported into the United States on November 17, 1993, and delivered to Chino, California. The airplane was shipped disassembled, wings and tail surfaces removed, in 40-foot shipping containers. The airplane was defueled when it was shipped. On March 15, 1994, the operator registered the airplane and applied for an experimental airworthiness certificate. The operator indicated in his application for the airworthiness certificate the airplane would be used for exhibition purposes. On June 6, 1994, the Federal Aviation Administration, Los Angeles Manufacturing Inspection District Office, issued a special experimental airworthiness certificate, and operating limitations. The FAA operating limitations, in part, limited the operation of the airplane to a one time flight to ferry the airplane to a new base of operations in Porterville, California, where test flights could begin. The limitations also restricted the airplane to operate in a defined geographical area for at least 5 flight hours with three takeoff and landings to a full stop, and away from densely populated areas and congested airways. The limitations specifically stated, "No person may be carried in this aircraft during flight unless that person is required for the purpose of the flight." The airplane landing gear system is hydraulically actuated and receives its hydraulic pressure from a pump mounted on the left-hand engine. A landing gear warning light is mounted in the front cockpit. The light illuminates anytime one or more of the landing gear are not down and locked when both engines are reduced below 18,000 rpm. The airplane fuel system consists of five fuel tanks; two wing tip tanks, two fuselage tanks located behind the rear cockpit, and a negative "G" flight accumulator located in the empennage. Servicing of the fuel system is accomplished through three filler ports, one in each wing tip tank and one in the aft fuselage tank, by gravity. The two fuselage tanks are installed in tandem order behind the rear cockpit and are of the rubber bladder type. Fuel flows between the two tanks via an interconnect tube. A single submerged boost pump in the rear tank supplies both engines with fuel and the upper chamber of the negative "G" flight accumulator. Fuel from the wing tip tanks is transferred to the forward fuselage tank by pressurized air, which is bled from the engine downstream of the compressor. The fuel level in the fuselage tanks is regulated by a float valve which opens when there is suitable space in the fuselage tanks to receive fuel from the wing tip tanks. The aircraft flight manual, normal operating procedures section, does not specify checking the fuel quantity or quality on the external inspection checklist. The forward fuselage tank has no filler cap or drain valve. The fuel quantity and quality in the forward tank cannot be observed during preflight checks. The rear fuselage tank has a fuel filler cap making it possible to observe the fuel quantity. The rear fuselage tank has a drain plug, but no drain valve. The purpose of the plug is to drain the entire fuel system when required by maintenance procedures. It is not possible to drain a preflight fuel sample without the risk of draining all the fuel in the fuselage fuel cells. The fuel system does not incorporate any means to sample fuel for quality assurance during preflight checks. WRECKAGE AND IMPACT INFORMATION The airplane initially collided with the eastbound lanes of Cover Street. The wreckage path followed a northwesterly direction aligned with the extended centerline of runway 30 for about 245 feet. During the impact sequence, the airplane struck the rails of a north-south Union Pacific railroad and came to rest inverted against a 12-foot-high dirt bank and above a buried natural gas main. The left wing tip tank separated from the wing and was lying on Cover Street. Aluminum was found transferred to the asphalt surface of the street. The street was covered with light soot. The burn area extended from the initial impact point to the airplane fuselage point of rest. The airplane fuselage and the bottom of the wings were also covered with soot. The fuselage was split circumferentially at the area of the aft fuselage fuel cell. The cockpit area was resting about 45 degrees from inverted on the left side and had been displaced nose left consistent with impact with the dirt bank. The remainder of the fuselage, from the engine inlet to the tail, and wings were inverted. The tail was being supported in a level attitude about 1 foot off the ground by the ruddervators. Fire had consumed the airplane structure between the aft cockpit and engine inlets exposing the control cables and wiring harness. Control continuity was established for all flight controls and engine and engine system related cables. The control cables and wiring harness from the cockpit were cut after documentation to facilitate recovery of the airplane wreckage. The airplane landing gear was found retracted. The wing flaps were extended about 15 degrees. The flight spoilers were found deployed. The airplane was then recovered to the Compton Airport for further examination. During the examination, both engine fuel cutoff valves were found in a symmetrical midrange position. The fuel cutoff handles were found split with the right engine handle forward of the left about 1.5 inches. The fuselage was suspended in a hangar in a level position. Fuel was found in internal fuselage fuel lines to the engine and was drained into clean white buckets. The fuel was amber in color and exhibited an aroma of jet fuel. The fuel was observed in the bucket to be hazy and contain particles. The fuel was then transferred into a clean lexan jar and swirled to create a vortex. Visually detectable particle matter was observed while the fuel was swirled. After the swirling action stopped, water appeared as a separate layer in the corner of the jar. The engines were examined and damage to the dome on the nose of the engine precluded any determination of throttle position. Examination of the internal stationary and rotating components did not reveal any evidence of mechanical failure or preimpact heat distress. The oil in the engines bearings was coked making it difficult to turn the engine spool. There was no evidence of bearing failure noted. MEDICAL AND PATHOLOGICAL INFORMATION Post mortem examinations on the pilot and passenger were conducted by the Los Angeles County Medical Examiner's Office on June 17, 1994, with specimens retained for toxicological examination. The results of the toxicological analysis on the pilot revealed negative findings for routine drug and alcohol screens. ADDITIONAL INFORMATION WRECKAGE RELEASE The wreckage was released to the representatives of the owner on June 21, 1994.

Probable Cause and Findings

A loss of power to both engines due to fuel contamination and, the pilot-in-command's failure to maintain an adequate airspeed during the subsequent emergency, which resulted in an inadvertent stall. Factors in the accident were: 1) the manufacturer's inadequate design of the airplane's fuel system, which does not facilitate fuel sampling during preflight inspections or routine normal maintenance; 2) the lack of a fuel drain valve in the fuel system for fuel sampling purposes.

 

Source: NTSB Aviation Accident Database

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