N186BA

HISTORY OF FLIGHT

On June 23, 1999, at 1446 hours Pacific daylight time, a Cessna 402A, N186BA, collided with two school buses while making a forced landing near the Van Nuys, California, airport. The forced landing was precipitated by a total loss of power in both engines while on a VFR approach for landing at the airport. The aircraft sustained substantial damage; however, the certificated commercial pilot, the sole occupant onboard, was not injured. A bus driver and 12 students received minor injuries. There were no injuries to the remaining second bus driver or 36 students. Sunshine Air, Inc., was operating the aircraft as a positioning flight under 14 CFR Part 91 when the accident occurred. The flight originated from the Laughlin/Bullhead International Airport in Bullhead City, Arizona, about 1328 mountain standard time. Visual meteorological conditions prevailed at the time, and no flight plan was filed.

The pilot reported that as he approached the Van Nuys airport, he had initiated his descent from 8,500 feet msl, and had lowered 15 degrees of flaps. At the time, he said the fuel gauges read: left main 7 gallons; right main 15 gallons; left auxiliary 2 gallons, and right auxiliary 5 gallons.

He reported his position to Van Nuys tower controller as being over Newhall Pass at 1440:58. He was subsequently cleared for a straight-in visual flight rules (VFR) approach to runway 16R and told to report over the San Fernando reservoir. He was cleared to land at 1442:00, and advised that winds were from 150 degrees at 10 knots.

As his descent continued to 3,000 feet msl, his left engine lost all power. He switched the fuel selector from the left main to the left auxiliary tank with auxiliary fuel pump on; however, the engine did not regain power. He then switched back to the left main tank.

Next the right engine lost all power about 1 minute after the first occurrence. Now descending through 2,000 feet msl, the pilot did not believe that he had time to attempt to diagnose the problem. At 1446:05, he declared an emergency over the tower frequency, saying that he had "lost an engine" and that "we're going down on the uh street."

The pilot planned an approach to Hayvenhurst Avenue and subsequently made an off-airport emergency landing on the city surface street about 2,200 feet northwest of the north perimeter airport fence.

After touching down about 600 feet north of the intersection with Parthenia Street at an estimated airspeed of 90 mph, the aircraft rolled south until it approached a traffic signal that had just turned red. At the same time, two school buses were simultaneously approaching each other from east and west on Parthenia Street, with a traffic signal that had just turned green.

As the school buses entered the intersection, both wing tips collided with the front of each bus as the airplane passed between them. Both main tanks (tip tanks) separated from the airplane and came to rest within the intersection. The pilot was able to brake the airplane to a stop about 1,500 feet south of the intersection. He reported to the tower controller that he was down at 1446:34, and then secured the cockpit before he deplaned.

At 0930, prior to his departure from Van Nuys, the pilot had requested that both his main tanks be topped off, and that 10 gallons be added to each auxiliary tank. He observed the refueling process and visually checked the fuel levels. The Peterson Aviation fueling log showed that a total of 89.5 gallons had been dispensed during the refueling operation. The exact amount of fuel on board at takeoff remains unknown.

According to the pilot, he had relied on a preplanned or "canned" flight plan and weight and balance form for the flight, which were, according to him, on file with the dispatcher. When the itinerary changed due to a perceived mechanical discrepancy, the pilot said he did not recompute the requirements for the flight.

After his initial departure from Van Nuys, en route to Grand Canyon, Arizona, the pilot noted a high cylinder head temperature reading (above red line) for his left engine. At the time there was no corresponding rise in left engine oil temperature observed. As a result of the single instrument reading, he made a precautionary landing in Bullhead City about 1215 mountain standard time.

He next contacted the dispatcher, who informed him that another aircraft would be dispatched from Van Nuys to take the passengers on to their destination. The airplane owner then instructed the pilot to reposition the aircraft back to the Van Nuys airport. The pilot reported that he did not add any fuel during his turn around at the Laughlin/Bullhead airport, which was more than halfway to his original destination.

After takeoff, he stated that he had climbed with 29.5 inches of manifold pressure and 2,450 rpm, as he always did. He stated that his cruise power setting had been 27 inches and 2,300 rpm. In his statement, he reported that the flight time from Van Nuys to Bullhead City had been 1.3 hours, with an indicated fuel flow of 18 gph per engine or 36 gph total for both engines. The pilot did not report leaning the mixtures. There are no performance charts published in the Airplane Flight Manual (AFM) for an engine that has not been leaned. According to the AFM performance charts, at the recommended cruise setting of 27 inches of manifold pressure and 2,300 rpm, the total fuel consumption should be 26.7 gph, if the airplane has been leaned properly. The maximum-allowable fuel flow is 31.83 gph at redline on the face of the gauge. His reported flight time from Bullhead City to Van Nuys on the return flight was 1.2 hours.

The pilot said that at some point, or points, during the flight he switched his fuel selector to his auxiliary tanks until the gauges read 2 and 5 gallons and then he had switched to his main tanks. He could not say how long he had been flying when he switched to the auxiliary tanks, or on which leg, or legs, this occurred.

PERSONAL INFORMATION

Sunshine Air had employed the pilot since July 1998 as a 14 CFR Part 135 charter pilot. Previously he had been employed as a flight instructor for Runway 3-7 Flight School, La Verne, California, from May 1996 until July 1998.

He attended the Professional Pilot Program at Sierra Academy of Aeronautics in Oakland, California, from March 1995 until February 1996.

He obtained his commercial pilot certificate on November 2, 1995, and his flight instructor certificate on May 5, 1996.

After being hired by Sunshine Air, he completed Aircraft Ground Training and Emergency Training (ground) on July 10, 1998.

According to the training records provided by Sunshine Air, the pilot completed his flight training and passed an Airman Competency/Proficiency Check administered by a check airman at Sunshine Air on July 17, 1998. During the check, the records showed that he satisfactorily performed landings with a simulated power plant failure as well as normal, abnormal, and emergency procedures. This was also his initial qualification in the Cessna 402A. On the following February 15, 1999, the records showed that he satisfactorily completed a similar flight check. His records further showed that he had maintained his currency consistently from July 17, 1998, until the day of the accident.

The pilot denied being tired or unrested for this, the first flight of the day, nor did the dispatch log have any record of him flying on any of the 3 days prior to the accident.

AIRCRAFT INFORMATION

Federal Aviation Administration airworthiness inspectors examined the airplane, engine, and propeller logbooks on June 23rd and 24th, 1999. They stated that the airplane was being maintained under an Approved Aircraft Inspection Program (AAIP). They reported that there were no open discrepancies, and that the records they examined, including applicable airworthiness directives (ADs), indicated that the airplane was being maintained in accordance with Federal Aviation Regulations (FARs) as was required by their operations specifications as a condition of their Part 135 certificate.

The pilot operating handbook (POH) states that the total aircraft fuel capacity is 143 gallons, which includes 51 gallons (50 gallons usable) in each main tank and 20.5 gallons in each auxiliary tank. Based on the last refueling, the airplane would have had no less than 122 gallons during its initial departure from Van Nuys.

Performance charts show that approximately 12 gallons of fuel is used during taxi, takeoff, and climb to 10,000 feet msl. According to performance charts provided by the airplane manufacturer, at the recommended cruise setting of 27 inches of manifold pressure and 2,300 rpm, the total fuel consumption should be 26.7 gph, if the airplane has been leaned properly. The maximum-allowable fuel flow is 31.83 gph at redline on the face of the gauge.

The POH also states that before starting the fuel selectors should be positioned on the right and left main fuel tanks. Before takeoff, the fuel selectors should be rechecked to make sure that they are both on the right and left main fuel tanks, and the auxiliary fuel pumps should be in the LOW position. After takeoff, climb, or low altitude cruise, the auxiliary pumps should be in the "OFF" position unless it is necessary to suppress vapor as evidenced by a "nervous" fuel flow needle. The auxiliary fuel pumps are located in the main fuel tanks and have no effect on fuel located in the auxiliary tanks.

The POH cautions that the main tanks must be selected for the first 60 minutes of flight. After 60 minutes of flight the auxiliary tanks may then be used. This is because the engine driven fuel pump supplies 150 percent of the fuel required to the metering valves for each engine. The excess 50 percent is returned to the corresponding main tank. When the fuel selector is on the auxiliary tanks, and if the main tanks have insufficient cap...