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July, August, 1996 Accident Reports
From CP86, Page 11 (October, 1996)
On August 6, 1996 after departing Oshkosh for a scheduled fuel stop in Cedar Rapids, a
Long-EZ pilot experienced a vibration that rapidly became very severe.
Suspecting a propeller failure, the pilot shut the engine down and pulled the nose up to bleed off airspeed in order to stop the propeller from wind milling while establishing a safe place to land.
On the ground the pilot discovered damage to the right side exhaust system where about 6 inches of the tailpipe was missing plus damage to one blade of the propeller. It was broken chord-wise at a point behind where the exhaust pipe exited the cowling, approximately 6" from the tip. This break was about 2" wide and from that point a tapering break toward the back of the prop running toward the hub for about 12". Everything outboard and aft was missing.
The pilot believes that the exhaust pipe broke and exited the cowling, striking and breaking one blade of the propeller. The first break set up a vibration that caused the second break.
After close inspections of the engine and mountings and a dial indicator check of the crankshaft flange for runout which indicated only about.0003 radial runout with Lycoming calling for .0005 or less, the pilot had a spare propeller shipped from home, installed it and ran the airplane up on the ground. He re-inspected the engine, mount and airframe and found no discrepancies. An additional inspection followed a 15 minute test flight, and a 30 minute test flight. Additional problems were not found.
On July 27, 1996 a Long-EZ pilot experienced an engine failure immediately after
takeoff, causing the airplane to crash into a wash and overturn. According to the pilot,
engine start and run-ups were normal. His Long-EZ has a two-tank, right or left, system
with an engine-driven fuel pump and an electric boost pump. Because his Ellison throttle
body injector doesn't like air bubbles in the fuel, he turns on the fuel pump and listens
until he hears fuel running into the left tank and sees fuel pressure on the gauge before
starting the engine, he said.
Fuel flow checks were later run on the engine and leveled fuselage. The pilot found that there was 1/3 gallon in the right tank and 2-1/4 gallons in the left tank. The tank vents were unobstructed. Fuel flowed freely at the gascolator outlet No fuel would flow to the throttle body even with the electric pump running. He disconnected the outlet line from the electric pump and got no fuel even with it running only about one drop per second. He removed the inlet line and got good fuel flow. He fueled each tank to one gallon and timed the flow. The left side drained the gallon in 4 min 53 see and the right in 4 min 43 seconds. He removed the electric fuel pump and attached to outlet of the gascolator with a flex line and positioned it lower than the electric pump running only one ounce per minute would come out of the pump.
The pilot feels the electric pump failing right after liftoff caused enough restriction to the fuel flow to cause the fuel to vaporize between the electric pump and the engine-driven pump.
NOTE., We are not familiar with the details of this aircrafts fuel system. In order to help prevent accidents RAF reports in the CP information received from EZ pilots, even though it relates to non-approved modifications or non-approved equipment. However, RAF does not recommend or endorse configurations we have not tested, ie., we can recommend and support only what is in the plans or in a CP mandatory plans change.