The commercial pilot reported that, during initial climb after takeoff, she heard a “loud bang” and saw flames coming from the trailing edge of the Beech 58’s right wing.
She was able to conduct an uneventful emergency landing near Baton Rouge, Louisiana.
The fire was located outboard of the right engine near the wingtip and auxiliary fuel tank. Black soot was visible near the right wingtip navigation and anticollision lights. Black soot and blue fuel stains were found near the fuel vents located on the bottom side of the wing under the right wingtip anticollision light.
Blue fuel stains were also found under the right wing near the main and auxiliary fuel tanks and inside the wing cavity near the electrical wiring for the right wing navigation light.
The examination of the right wing revealed that the wiring for the right wing anticollision light was crimped together with “handshake” connectors and then wrapped with electrical tape. The wiring was not properly insulated.
The source of the fuel leak could not be determined because of the substantial damage to the right wing caused by the fire.
About 6-1/2 years before the accident, the airplane manufacturer issued a Safety Communique titled, “Outboard Wing Fire Potential Due to Fuel Leaks and Electrical Wire Chafing.” The communique advised owners of a potential safety issue concerning loose wiring and fuel fumes in the structural areas of the airplane.
The communique reminded owners to maintain the fuel and electrical systems in accordance with the maintenance manuals and to ensure there were no visible fuel leaks around the vents and sump drains.
It further stated that no fuel leaks or staining should be observed around the vents and sump drains during preflight inspections.
Based on the post-accident examination, the fuel leak found on the bottom of the right wing might have been a preexisting condition. However, the pilot did not remember seeing any fuel staining during the preflight.
The evidence further suggests that the initial ignition occurred behind the anticollision light in the right wingtip as a result of an improper repair, during which the anticollision light wiring was not properly insulated, which resulted in the ignition of combustible fuel vapors in the outboard section of the right wing.
Probable cause: The improper insulation of the anticollision light wiring, which resulted in the ignition of combustible fuel vapors in the outboard section of the right wing. The source of the fuel leak could not be determined due to fire damage.
NTSB Identification: CEN18LA221
This June 2018 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.
Problem not that unusual. I was flying in the back of a C182 on a fire patrol, up front the pilot (a contractor) was in the left seat and another fire fighting employee observer (also pilot rated) occupied the right seat. As we turned into the sun (toward the south) I saw a tendril of smoke curling up from the center of the glare shield. I said “smoke” about the same time the pilot (left seat) and observer (right seat) smelled burning insulation. I never saw the pilot’s hand hit the master switch rocker – it was FAST. We turned an headed to the nearest asphalt airstrip as the smell (and visible smoke) went away as soon as the master switch was off. An IA/A&P on the field looked over the wiring behind the panel and found nothing. The pilot (contractor) flew the plane home where an avionics shop went through the wiring and again found nothing. So $5,000 later (according to the owner of the aircraft) the plane had new panel wiring, no no solid ‘smoking’ gun to identify the smoke and odor. Electrical fires are insidious and not always easy to find the fault.
I had a panel fire (except I didn’t know that it was panel) during a flight from Houston to ElPaso in a Piper PA30. Piper had the post light wiring installed, as standard, behind the plastic panel overlay, common on all older Pipers. It turned out that a screw head on the under portion of the panel had been rubbing on the plastic tube that protects the actual wires to the post lights and had chosen this 4000 TT moment to arc from the wire. As I cross HOU I turned on lights entering night, and I began to smell what was like freshly cut wheat. Then it became like a forest fire. Then it became acrid. Initially I thought the aroma was from outside, despite my not seeing fires along the route.
When I realized that it was an electrical fire I advised ATC of the problem and I turned off the master switch. The acrid smell ceased. I could see the glow of El Paso in the distance so I elected to continue. I turned on the master and one navcom outside El Paso, ATC gave me an immediate clearance, and I landed safely. The next day I trouble shot and found the problem. It had been sizzling, not flaming, but it could have.
This was not germane to the make and type, but a factory problem. After 4000 hours TT who would have thought? I reckon had a mechanic seen the plastic protective tube worn through that he might have raised the issue?
🤣🤣🤣. Good comment, Doug!!!
After I changed my underwear, I’d find that mechanic and shoot him.