Aviation Accident Summaries

Aviation Accident Summary LAX03FA013

Agua Dulce, CA, USA

Aircraft #1

N700US

Piper Aerostar 601

Analysis

The airplane crashed into rising terrain after departure from an uncontrolled public airport. The runway used by the pilot is 4,600 feet long and has a 1.8 percent upward gradient. The density altitude was 4,937 feet msl, and a slight quartering tailwind existed at the time. The pilot held in position, powered up the engines, and started his departure. The airplane was observed using most of the runway length before rotation and then it assumed a higher than normal pitch attitude in the initial climb. Witnesses watched the airplane turn left following the route of a canyon and into rising terrain. The reciprocal runway departs towards decreasing elevations. In the area of the crash, two witnesses reported the airplane was at a low altitude, nose high, and wallowing just before it descended into a drainage area 0.69 miles from the runway. Post accident examination of the engines revealed worn camshaft lobes and tappets, which would negatively affect the ability of the engines to produce full rated power. One engine exhibited severe rust on the entire crankshaft. The accident site was located in a canyon, and the wreckage and ground scars was confined to an area about the diameter of the wing span. Major portions of the airframe and most of the engine accessories were consumed by a post accident fire. Examination of the wreckage established that all major components of the airframe and powerplants were at the site.

Factual Information

HISTORY OF FLIGHT On October 20, 2002, about 1300 Pacific daylight time, a Piper Aerostar 601, N700US, collided with terrain after departure from Agua Dulce, California. The airplane was operated by the owner/pilot under 14 CFR Part 91. The private rated pilot, a passenger who held a student certificate, and rear seated passenger were all fatally injured. The airplane was destroyed. Visual meteorological conditions prevailed for the personal flight, and no flight plan was filed. The flight was originating and destined for Bullhead City, Arizona. According to witnesses, the airplane had landed, possibly to pickup a passenger, parked, and remained on the ground for a short period of time. Subsequently, the airplane was seen to taxi out for departure on runway 04. The pilot held in position, powered up the engines, and started his departure. The airplane was observed using most of the runway, rotate, and assume a higher than normal attitude. Witnesses watched the airplane turn left following the route of a canyon and rising terrain. In the area of the crash, two witnesses reported the airplane was low, nose high, and wallowing just before it descended into a drainage area 0.69 miles from the runway. PERSONNEL INFORMATION The pilot held a private certificate with ratings for airplane single and multiengine land and instruments limited to single engine land. The pilot's last documented third-class flight physical occurred on June 13, 2001. According to a recovered damaged flight logbook, the pilot had accrued about 685 total flight hours. The accident airplane first appeared in the pilot's logbook about March 1, 2001, about 500 hours into his total flight time. According to Federal Aviation Administration (FAA) records, on July 28, 1999, the pilot obtained a student pilot certificate with the issuance of a third-class flight physical examination. On April 19, 2000, he applied for, and received, a private pilot certificate, having accrued 265 flight hours, with 240 hours of dual flight instruction and 25 hours of solo time. On August 4, 2000, the pilot applied for an airplane multiengine rating. He was reporting 315 total hours, with 265 hours of dual flight instruction and 25 hours in multiengine type. The pilot failed the check ride and was reexamined and issued the multiengine rating on August 5, 2000. On October 17, 2001, the pilot applied for an instrument rating and was reporting 639 total hours and 517 dual flight hours. The pilot failed the check ride and was reexamined and issued the rating for single engine only on October 18, 2001. On October 20, 2001, the pilot applied for a multiengine instrument rating and was reporting a total flight time of 640 hours with 522 dual instruction on the application. The pilot failed the flight test. STUDENT PILOT PASSENGER The right front seat passenger obtained a student pilot certificate on October 10, 2001. AIRCRAFT INFORMATION An annual inspection was performed by Able Air Corporation and repairs were finalized on December 6, 2001. The airplane was signed off as unairworthy, with a list of discrepancies given to the pilot/owner. Subsequently, another maintenance organization at Long Beach, California, approved the airplane for return to service on December 12, 2001, at 14,235 total flight hours. The most recent maintenance performed on the airplane was at Lloyd's Aircraft Maintenance, Bakersfield, California. On September 25, 2002, Lloyd's invoice 9472 documents the adjusting of engine operating limits, at the request of the customer, about 29 hours since the last annual inspection. The engines's turbocharger exhaust system is designed to maintain sea level manifold pressure (MAP) to a given altitude. It does not provide MAP boost to the engines. According to the Aerostar model 601 flight manual, takeoff power is at 2,575 rpm and 29.5 inches of MAP. The pilot's home base airport manager was asked about fueling record information and an unidentified fuel truck observed at the pilot's hangar a few days before the accident. The manager stated that the pilot had made allegations to the Los Angeles Department of Weights and Measures that employees of Raytheon Aircraft Company, Van Nuys, California, were manipulating the fuel log and overcharging on fuel quantity, and consequently on price. METEOROLOGICAL INFORMATION The nearest official weather reporting site was Palmdale, California, 14 miles northeast of the accident site. At 1253, Palmdale was reporting: variable wind at 4 knots; visibility 10 miles; temperature 75 degrees Fahrenheit; dew point 37 degrees Fahrenheit; and the altimeter was 29.93 inHg. According to witnesses, the active runway was 04 as determined by the windsock and traffic. About the time of the accident airplane's departure, the wind had started to favor runway 22. A witness estimated the temperature to be about 85 degrees Fahrenheit at the time of the accident. A pilot landed on runway 04 about 15 minutes behind the accident airplane. He reported a direct headwind with the windsock deflected at 45 degrees. The witness/pilot also observed the accident departure and reported that the wind was now calm, and the engines were in sync and sounded very smooth. He was concerned about the rate of acceleration. According to a Safety Board density altitude computer program, using the witness estimate of 85 degrees Fahrenheit, the airport elevation, and the Palmdale altimeter of 29.93 inHg, the density altitude was calculated at 4,937 feet mean sea level (msl). WRECKAGE AND IMPACT INFORMATION The wreckage site was located in a canyon/wash, and was confined to about the diameter of the wing span. Major portions of the airframe were consumed by a post accident fire. A Safety Board examination of the remains provided indicators that all major components of the airframe and powerplants were at the site. Portions of the exterior skins revealed the airplane to be stripped of paint and exterior placarding. The wreckage was recovered to a secure storage area for detailed examination by the Safety Board and parties to the investigation. The airframe was examined for control continuity where possible. The braking and parking brake system was examined. The landing gear was found in the retracted position with the flaps up. Trim tab positions were not recovered. The Safety Board witnessed the disassembly of both engines. Extensive rust was found on the right engine crankshaft. The interior of both crankshafts were heavily laden with sludge, as were portions of the propeller shafts. The camshafts in both engines displayed worn lobes with spalling type damage to the tappets. The magnetos were fire damaged, as were all other accessories. MEDICAL AND PATHOLOGICAL INFORMATION On October 21, 2002, the Los Angeles County Medical Examiner performed an autopsy on the pilot and student rated passenger. During the course of the procedure samples were obtained for toxicological analysis by the FAA Civil Aeromedical Institute, Oklahoma City, Oklahoma. The results of the analysis were negative for carbon monoxide, cyanide, and ethanol for both pilots. The analysis for the private pilot operator was positive for Butalbital, which was detected in the blood at 0.796 (ug/ml, ug/g) and 2.214 (ug/ml,ug/g) in the liver. Fluoxetine was detected in kidney and liver samples. Norfluoxetine was detected in kidney and liver samples. The Los Angeles County Department of Coroner also performed a toxicological analysis. The analysis of Femoral blood samples was positive for Fluoxetine at 0.48 (ug/ml) and Norfluoxetine at 0.50 (ug/ml). Blood samples obtained from the heart were positive for Butalbital at 0.72 (ug/ml), Fluoxetine at 1.2 (ug/ml), and Norfluoxetine at 0.76 (ug/ml). Pilot medical records were obtained from the FAA Civil Aerospace Medical Institute, Oklahoma City. Examination of the records revealed no FAA approvals for the use of the prescription drugs found during the toxicology analysis. AIRPORT INFORMATION The Agua Dulce Airpark is a privately owned public airport. The elevation is estimated at 2,660, feet msl. The available runway length is listed as 4,600 feet. There are landing displaced thresholds for obstruction clearance on both runway 04 and 22. According to an FAA Airport Master Record of site survey dated June 20, 1995, runway 04 has a 1.8 percent upward runway gradient. Two other sources of airport information, FAA Airport/Facility Directory and Flight Guide for western states, did not note a gradient. Runway 04 departs towards rising terrain and runway 22 departs towards lower terrain. The airport is uncontrolled with a midfield windsock. A Common Traffic Advisory Frequency of 122.9 is available for pilots to share information. TESTS AND RESEARCH The damaged camshafts and tappets were shipped to Lycoming for examination. The parts were identified by Lycoming as not being their parts and returned to the Safety Board. A Lycoming representative stated that the camshafts may be a product of Air Support International. Examination of the right engine revealed five tappets were spalled, or worn, in a concave pattern from a 0.0005 to 0.006-inch depth. The cam lobe point wear was measured about 1.475 inches high to a low of about 1.348 inches. Large areas of rust were noted on the camshaft bearing surfaces. Examination of the left engine revealed one worn tappet, with a concave measured wear depth of 0.004 inches. The highest camshaft lobe measured about 1.480 inches, and the lowest lobe point was 1.420 inches. According to a Lycoming publication, the cause of unusual camshaft and tappet wear is corrosion, and commonly seen in low use airplanes. The low usage causes corrosion from the loss of oil coverage. The moisture is a product of combustion, as are the acids in the oil. The corrosion pitting destroys the case hardening surface of the lobes and tappets. Once the case hardening is destroyed, the softer metal wears quickly. The same type wear will also occur from an improperly reground camshaft. As the lobes wear down or lose their profile, optimum engine performance is less likely. A factory representative stated that the only way to quantify a loss of engine power is to install the defective parts into a new engine and run it in a test cell. In turbo charged or turbo normalized installations, the affects of cam lobe wear can be compensated for by ground adjustments. ADDITIONAL INFORMATION The wreckage was released to the insurance company representative on July 24, 2003.

Probable Cause and Findings

the pilot's failure to attain and maintain a sufficient airspeed, which led to an inadvertent stall mush. The pilot's selection of the wrong runway for departure, considering the uphill gradient, the wind direction, and a takeoff path into rising terrain are also causal. The high denisty altitude and the degraded internal condition of the engines were factors.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports