Imbalance Noted Between Left, Right Wing Tanks

Preliminary findings in the National Transportation Safety Board's investigation into an incident last Thursday involving a Cape Air Cessna 402C indicate the aircraft's two piston engines suffered fuel starvation due to a stuck valve.

The Cape Cod Times reports Flight 9399 was en route from Key West, FL to Fort Myers when the plane's pilot reported a complete loss of engine power. The pilot glided the aircraft to a safe landing at Naples Municipal Airport, and neither the pilot nor the six passengers onboard were injured.

While the investigation is expected to take several months, NTSB senior investigator Tim Monville said the Board confirmed a fuel distribution valve in the left tank was stuck, meaning both engines were drawing fuel from the aircraft's right fuel tank.

Investigators also noted there were 12 gallons of avgas in the right tank... and nearly 46 gallons in the left. "We proved repeatedly that the left tank was not providing fuel to the left engine," he said.

Cape Air personnel told the NTSB they suspect fuel transferred from the right tank overnight. When the stuck valve was lubricated, both engines started and the plane made a routine ferry flight to Fort Myers, where the suspect parts were removed for further investigation.

Dan Wolf, CEO of Cape Air, noted the pilot could have bypassed the stuck valve in flight, and continued on to Fort Myers... but when the pilot saw Naples nearby, Wolf says the pilot opted instead to take a cautious route.

"It reflects very well on the training and the experience level of the pilot," Wolf said, adding the pilot did the "smart and prudent thing."

When queried whether he had noticed the fuel imbalance prior to, or during, the flight, the pilot told the NTSB he did notice the lower fuel level on the right side... but believed there was a problem with the fuel gauges.

We suspect the NTSB hasn't had its last word on this one just yet.

FMI: www.capeair.com, www.ntsb.gov