NTSB Factual Report

On May 7, 2006, about 0800 mountain standard time, a Boeing Stearman E75, N5263N, encountered terrain during a forced landing near Show Low, Arizona. The pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The private and one passenger were not injured; the airplane sustained substantial damage. The local personal flight departed Show Low about 1 minute earlier. Visual meteorological conditions prevailed, and no flight plan had been filed.

The pilot submitted a written statement. He pulled the airplane from his hangar, and completed a preflight inspection. He checked the oil level, sumped the fuel, and noted no abnormalities. He secured his passenger in the front seat, and started the airplane without difficulty. He taxied for takeoff, brought the mixture to rich, set the engine to 1,700 rpm, and completed a run-up check. The magneto check, propeller, throttle, gauges, and controls were within normal limits. He set the trim, and announced his intention to depart on runway 24 after the oil reached operating temperature.

The pilot applied full throttle, and flew off at 65 mph. The airplane climbed to 300 to 400 feet, and he pulled the propeller back for noise abatement. He noticed that the airspeed was low, so he lowered the nose, checked the trim, throttle, mixture, and made sure that the magneto switch was on "both." He pushed the propeller control full forward, but the airplane was still not climbing. He maintained altitude, airspeed, and heading. He wanted to make sure that he cleared power lines and buildings at the departure end of the runway. He hoped to gain enough airspeed and lift to reach alfalfa fields, or make a slow turn back to the airport. The engine failed to generate enough power to maintain flight, and the situation became worse the longer he was airborne. With diminishing altitude and airspeed, he became concerned about a possible stall/spin. He slowly banked toward a field, and advised on CTAF that he had a problem. He pushed the nose over, and took what he could for a landing location. He landed in terrain about 300 yards from the airport. The landing gear separated and, the lower wings sustained substantial damage.

Conquest Aviation personnel examined the engine under the supervision of the Federal Aviation Administration (FAA) at Show Low on May 6, 2006. Conquest Aviation submitted a written report, and the FAA inspector who observed the inspection concurred with the facts in the report.

Technicians examined the engine on the airframe, and removed the top spark plugs. All spark plugs were clean with no mechanical deformation. The spark plug electrodes were black and sooty, which they said corresponded to an excessively rich mixture. The FAA inspector noted that witnesses observed black smoke trailing the airplane during takeoff.

The fuel selector valve was in the off position. The fuel caps were in place, vented, and the vents were clear. The fuel tanks were not ruptured; the drain for the left tank did not work. The fuel tanks, screens, and gascolator contained a fluid that was blue, clean, and smelled like AVGAS.

Bendix manufactured the carburetor. The fuel lines leading to the carburetor were clear. There was fluid present in the lines, bowl, and finger screen that was blue, clean, and smelled like AVGAS. The metal floats were intact. The accelerator pump was operative. The carburetor heat control was in the OFF position. The FAA inspector noted that the carburetor heat control was not rigged properly; the carburetor heat was open 1 inch when the carburetor heat control on the panel was in the OFF position. The throttle moved freely and was closed. The mixture was open and moved freely.

The oil screens were contaminated with minor non-ferrous metal and possible silicone debris.

The airplane was equipped with a Hamilton standard propeller. The propeller governor was overhauled by Rocky Mountain Propeller on June 20, 2001, and installed by IA #497523578. Blades 1 and 2 were curled from impact.

The FAA inspector reported that there was a patch around the air intake duct. After lifting the patch partially off, he noted that the duct's inner support wire had collapsed. The duct collapsed inward as well. He opined that this restricted the air flow, and enriched the fuel mixture, which resulted in the loss of power.

NTSB Probable Cause

the collapse of the air intake duct resulted in a loss of engine power. A factor was the uneven terrain in the landing area.