At first glance, one might expect that high density altitude was the cause of last week’s fatal Comanche crash at Truckee-Tahoe airport.  The pilot first attempted to depart with three aboard, but aborted the takeoff.  He then offloaded his two passengers and tried again.  It was on the second attempt that the pilot crashed into hangars.

No doubt about it:  Because of its altitude, Truckee is a difficult airport, especially in the summer whenTruckee-Tahoe Airport the air is thinnest.  In fact, last week’s crash was the ninth at the airport in the past four years.  High density altitude played a role in a number of those crashes, including the Karen Trolan crash.

But the facts don’t quite add up on last week’s accident.  The pilot flying the accident aircraft (Piper N8218P) was very experienced – he reportedly had in excess of 6000 flight hours.  And though a departure with three aboard may have taxed the abilities of the plane and its pilot, with only the pilot aboard, there shouldn’t have been much of a problem.

Whenever an aircraft crashes on takeoff, the NTSB tests the fuel supply at the departure airport.  It’s always possible that an engine failure contributed to the crash, and one possible cause of an engine failure is contaminated fuel.

Today word is out that the fuel supply at Truckee did not meet the standards.

From an email I received from San Mateo County Airport: 

After a fatal accident at Truckee (KTRK) on the 2nd of August, the industry-standard practice of halting fuel service and testing the fuel in all tanks and trucks revealed that the 100LL fuel stored at KTRK did not meet the American Society for Testing and Materials (ASTM) standards for 100LL.  As a result of these tests, 100LL fuel service at the airport continues to be suspended pending new fuel and testing of its quality.

Truckee Airport has been trying to get in touch with all pilots who purchased fuel between July 20th (the last fuel delivery) and August 2nd (the day of the accident) and have asked us to pass along this information to pilots at San Carlos/Half Moon Bay.  Questions about the above-mentioned issue should be directed to World Fuel Service’s area representative Mike Montalvo at: 510-604-6511.

The test results don’t prove that bad fuel caused the Comanche crash but, at this point, bad fuel can’t be ruled out.