Inadequate inspection leads to fatal crash

Aircraft: Piper Cherokee Six. Injuries: 3 Fatal. Location: Jackson, Miss. Aircraft damage: Destroyed.

What reportedly happened: The airplane had been stored in a hangar with its fuel tanks half full under varying temperature conditions. The accident flight was the first time in two months the plane had flown.

On the day of the accident, the pilot had planned on flying to a safety seminar, so he had the airplane pulled out of its hangar, and its main fuel tanks were topped off from a fuel truck. After his arrival at the airport, the pilot performed a preflight inspection. The manager of the hangar facility described the pilot’s preflight inspection as “real quick.”

A lineman observed the pilot in a position to reach the fuel strainer valve, but he did not see the pilot sump the main fuel tanks. When the lineman drove by the airplane, he saw a puddle about one foot in diameter on the tarmac beneath the fuel strainer, but he did not note anything under either main fuel tank drain.

The lineman also noted that the airplane had an under-inflated tire, but, due to other duties, he could not warn the pilot before he taxied the airplane away.

About two minutes after takeoff, the pilot reported an “engine problem” to air traffic control and turned  back toward the airport. According to witnesses, the airplane descended at a steep angle, consistent with a stall. The airplane crashed into a house near the airport and both the house and airplane burned.

The post-accident examination revealed evidence indicating that the airplane was not under power at the time of the crash. No pre-existing mechanical anomalies were found that would have precluded normal engine operation.

However, when the fuel flow divider was opened, water was found in it, which likely resulted in the loss of engine power.  Investigators determined that the fuel cap was likely not the source of water since the airplane was stored in a hangar.

Contaminated fuel from the fuel truck was also not the likely source of water since the truck was reportedly sumped daily. On the day of the accident, five airplanes received fuel from the same truck before the accident airplane with no reports of any performance anomalies, and a clean fuel sample was taken from the truck about 20 minutes after the accident.

Investigators determined that it was more likely that condensation occurred in the half-filled fuel tanks during the previous two months that the airplane was sitting in the hangar under varying temperature conditions. There was not enough evidence to determine whether the pilot actually drained each main tank to ensure that all of the water was removed. It is likely that the pilot either did not sufficiently drain the main fuel tanks or that he was relying on draining the main fuel tanks through the fuel strainer and fuel lines and did not sufficiently drain them all. Given witness statements indicating that the pilot was in a hurry and his oversight of the under-inflated tire, it is likely that the preflight inspection was inadequate, which resulted in his failure to notice the fuel tank condensation.

Probable cause: The pilot’s inadequate preflight inspection, which resulted in his failure to note the water in the fuel tank due to condensation, which subsequently shut down the engine in flight.

NTSB Identification: ERA13FA055

This November 2012 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.