NTSB Factual Report

HISTORY OF FLIGHT

On April 13, 2005, about 1055 mountain standard time, a Cessna T210M, N732SY, experienced a loss of engine power and collided with a semi-truck while performing a forced landing on Interstate 17 in Phoenix, Arizona. Caddo Investments, Inc., was operating the airplane under the provisions of 14 CFR Part 91. The commercial pilot, the sole occupant, sustained serious injuries; the airplane sustained substantial damage. The personal cross-country flight departed the North Las Vegas Airport, Las Vegas, Nevada, at an unknown time, with a planned destination of Phoenix Deer Valley Airport, Phoenix. Visual meteorological conditions prevailed, and a flight plan had not been filed.

The National Transportation Safety Board investigator-in-charge (IIC) conducted a telephone interview with a pilot/witness who was flying his airplane behind the accident airplane. He stated that while he was on a 3-mile base leg in the traffic pattern for runway 07L, the accident pilot transmitted over the radio that he wanted to declare an emergency. The tower controller informed the pilot that he could land on any runway he desired and began diverting the airplanes that were in the vicinity away from the runways. Shortly thereafter, the pilot reported that he was not going to make it to the airport.

Two witnesses reported to a Federal Aviation Administration (FAA) inspector that prior to impact, the airplane's engine was emitting black smoke. An additional witness, who reported seeing the airplane during the accident sequence, stated that he did not observe any smoke.

The Safety Board IIC interviewed the pilot about a month after the accident. He stated that as the airplane entered the 20-mile vicinity from the airport, he switched the fuel selector to the fullest tank. He scanned the cockpit gauges (including the cylinder head temperature gauge) and noted no anomalies. As the airplane descended to pattern altitude he manipulated the throttle control in effort to maintain level flight. While pushing the throttle control forward, with the manifold gauge showing about 20 inches, the engine sputtered and quit. With the airplane at such a low altitude, he realized that the airplane would not be able to reach the airport, and he began searching for the best terrain to perform an emergency landing. Being in a congested area, he opted to land in the grassy median between the freeway lanes. The pilot further stated that he did not observe or smell smoke during the accident sequence.

AIRPLANE INFORMATION

The Cessna T210M, serial number 21061749, was manufactured in 1977. According to the aircraft maintenance records and the recording tachometer in the cockpit, it had accumulated a total time in service of 3,731.5 hours. The most recent annual inspection was recorded as completed on September 08, 2004, corresponding to 60.5 flight hours prior to the accident. According to the maintenance records, the Continental TSIO-520-R engine, serial number 512130, was the original Cessna factory installation in the airframe and had accumulated a total time equal to that recorded for the airframe. A review of the engine logbook disclosed that a top overhaul and annual inspection was entered as completed on September 08, 2004, coinciding with the annual inspection recorded in the airframe record.

The co-owner of the airplane confirmed that a notebook found in the wreckage was a flight activity log. A review was completed of all the entries in the notebook. Each line entry contained a recorded date, airport identifiers, tachometer times, and a total trip time. The last entry made was dated April 10, 2005. The entry indicated that a 3.1-hour trip was completed, ending at a tachometer time of 3,729.4 hours, 2.1 hours prior to the accident. A notation on the last entry indicated that 1 quart of oil was added at that time. A discrepancy was noted on the September 07, 2004, entry, which stated that the "fuel remaining doesn't seem to work."

The gravity fed fuel system is designed for fuel to flow from both of the integral wing tanks through a fuel line, until reaching two separate reservoir tanks (located under the cockpit area). The fuel continues from the reservoir tanks to a fuel selector value, which the pilot can manipulate via a lever inside the cockpit (the lever is connected to the selector by means of a single shaft). The fuel selector positions are as follows: LEFT ON, OFF, and RIGHT ON; when moving to either tank, the selector passes through the OFF position. The fuel will continue to flow through a strainer to the engine driven fuel pump, bypassing the auxiliary fuel pump (when it is not in operation). The fuel will then be pumped to the air/fuel control-metering unit and directed to the spider valve where it is evenly dispersed into each cylinder through a fuel injection nozzle.

A review of the fueling records at the North Las Vegas Airport disclosed that the last documented fueling of the airplane occurred on April 10, 2005, with the addition of 60.57 gallons of 100LL aviation gasoline.

TESTS AND RESEARCH

An examination of the wreckage was conducted on April 26, 2005, by Safety Board investigators and representatives from both Cessna Aircraft and Teledyne Continental Motors at Air Transport, Phoenix.

Airframe

As viewed at the wreckage facility, the airframe was segmented into three main sections, after being severed for recovery purposes.

The cabin structure consisted of the cockpit area from the leading edge of the wings, aft to the bottom of the rear window frame. Both wings remained attached to the structure. The firewall and instrument panel were separated from the airframe and both front seats were detached from their corresponding rails. The main landing gear, still attached to the airframe, was extended. The nose gear separated from the airframe.

A portion of the empennage, encompassing the airframe from the aft baggage compartment bulkhead to the tail section area, contained several navigation equipment boxes as well as the emergency locator transmitter (ELT). The control cables in this section were cut during the wreckage recovery. The control cables were intact and positioned along their typical runs. Investigators noted no anomalies.

The tail section remained intact with all control surfaces attached at their respective hinges. Investigators manipulated the severed cables in the tail cone (cut during recovery), revealing that both the rudder and elevator control surfaces moved individually when a pull force was applied to it's corresponding cable. Investigators measured the trim tab actuator to be positioned at 1.5 inches, which the Cessna representative attributed to correspond to the neutral position.

The right wing exhibited aft crush deformation to the leading edge, extending across the entire wingspan uniformly. The crush was 90 degrees to the chord line with the leading edge appearing to have folded into itself, giving it an accordioned form. The crushed aluminum leading edge surface revealed blue color streaks, which were visually similar in color to the painted wood atop the truck that the airplane collided into.

The left wing remained intact and did not appear to sustain any deformation. On the upper surface of the wing, investigators noted a dark stain from the forward lip of an inboard fuel bladder inspection panel continuing aft several inches, consistent with the airflow direction.

Investigators established flight control continuity from both ailerons to their respective doorpost, where the cables were cut. The wing flap actuator jackscrew measured 1.6 inches, which according to the Cessna representative, corresponded to a flap extension of about 20 degrees.

The instrument panel and adjacent cockpit area (forward of the seat rails), was severely impact damaged and fragmented. The examination of the instrument gauges disclosed a tachometer time of 3,731.5. The landing gear selector handle, and flap lever, were situated in the full down (extended) position.

The gascolator separated from the airframe and sustained visible external damage. The internal screen was clean and free of any contaminates, although it sustained vertical crush deformation. There was no fuel found in the gascolator housing. The fuel selector handle, which had sustained damage and found in impact damaged debris, was positioned past the left fuel tank indication (hyper extended counterclockwise), with the indication plate loose at its respective attach points.

The split-rocker type auxiliary fuel pump switch was positioned with one side (yellow) in the up position, corresponding to the "ON" position.

The left wing fuel tank appeared to be intact, and the right wing fuel tank was ruptured at the leading edge. Both of the wing's vented fuel filler caps were affixed securely to their respective openings on the upper wing surface; the seals on each cap were intact with no anomalies noted.

The left reservoir tank remained intact, under the pilot's seat rails in the cockpit and the right reservoir tank separated from the airframe. Investigators removed the back housing of the fuel selector valve, noting the bottom rotor port positions. The Cessna representative stated that the positions corresponded with the fuel selector being between the LEFT tank and the OFF positions, favoring the OFF position. The engine driven fuel pump remained intact and secured at its respective flange. After connecting the auxiliary fuel pump to a 12-volt battery, investigators heard the pump operating internally. The disassembly of the spider valve revealed that the spring and rubber diaphragm remained intact and the screen was free of debris and contaminants; there was no fuel found.

Engine

The engine was detached from the airframe, and impact damage was observed on numerous areas of the crankcase. Visual examination of the engine revealed no evidence of premishap catastrophic mechanical malfunction or fire.

The fuel injector nozzles remained secured in their respective cylinders with the exception of the nozzle on the number 5 cylinder, which was broken at the base. The bottom of the nozzle was still affixed into the borehole and the face of the fractured surface was angular and granular. Damage to the cylinder fins was noted on the number 5 cylinder, where crush deformation was observed to originate in the nozzle area extending about 8 inches diagonally toward the number 2 cylinder. At the base of each injector nozzle a dark blue residue coated the nozzle surface extending upward about an inch. The corresponding cylinder surface area immediately surrounding the nozzle also contained the blue coating. On several cylinders the blue stain covered a larger area, extending to parts of the fins.

All six fuel injector nozzles were internally clean from contaminates and debris. The upper air deck tubing was clear and mounted securely to the injector nozzles.

Investigators achieved manual rotation of the crankshaft by turning the propeller blades that remained affixed to the crankshaft flange. Thumb compression was established in all cylinders with the exception of the number 2 cylinder, which was visibly cracked. Valve train continuity was observed, with equal lift action at each rocker assembly; oil was found in the rocker box areas on all cylinders.

Removal of the number 1 cylinder revealed no evidence of internal stress inside the crankcase. The cylinder combustion chamber had very light combustion deposits, and the intake and exhaust valves were unremarkable; the cylinder wall did not display any scoring or evidence of heat distress. The accompanying piston was intact and moved freely on the securely attached pin. The piston crown appeared to be in a near new condition, with very light combustion deposits evident. The piston rings were intact and moved freely.

One of the two magnetos was found loosely attached to the engine and observed to have sustained external damage. The only remnants found of the other magneto was the impulse coupling; the casing was not located. Due to the extent of the impact damage, the magnetos could not be functionally tested, nor could the engine timing be ascertained.

The Auburn Spark Plug CO. AC-283 spark plugs were secured at each position with their respective lead attached. The spark plug electrodes were undamaged, displaying dark black soot coloration on the face of each spark plug; the bottom numbers 2, 4, and 6 spark plugs were coated with a dark, oily residue.

Investigators looked at the accessible internal walls of both the intake and exhaust ducts. Oily residue was found coating the internal and external surfaces of the ducts.

The oil suction screen was found secure and uncontaminated. The oil filter was removed and cut open, revealing a clean internal filter. There was no evidence of any preimpact lubrication system contamination.

The Kelly Aerospace turbocharger (part number 406610-9005) remained secured to the engine on its respective mounting pad. Removal and partial disassembly of the turbocharger revealed an oily film on the compressor back plate adjacent the compressor wheel. The internal walls of the compressor housing also displayed an oily residue, which made a thin coat over the surface. The shroud of the compressor housing that surrounds the compressor wheel, showed slight machining, with circumferential scoring evident on the interior surfaces, in plane with the impellor blades. Investigators noted a partial piece of a blade missing on the turbine wheel and similar machining signatures in the shroud of the turbine housing surrounding the turbine wheel. Several additional impeller blades were slightly rubbed with shiny metal showing and curved at the tips, displaced opposite the direction of rotation. Both the compressor and turbine wheels rotated freely.

The turbocharger waste gate controller and valve housing were impact damaged; the valve was found about 90 percent closed.

Additional Testing

The following parts were retained for further testing: turbocharger, three randomly selected spark plugs, fuel pump switch, and the engine driven fuel pump. The parts were sent to Teledyne Continental Motors and examined under the auspices of a Safety Board investigator. There were no indications or evidence of a component failure or preimpact malfunction.

A Shadin Avionic fuel totalizer unit had been installed on the airplane. It was sent to the manufacturer in an effort to extract information from the non-volatile memory. No meaningful data was obtained.

NTSB Probable Cause

a loss of power for undetermined reasons.