After about 50 hours my alternate air (built to plans, vertical induction fuel injection) door pulled the rivets right through the FAB fiberglass. No big deal since no loose parts were available to be sucked into the engine. I built a U shaped backing plate inside the FAB so the rivets would go through metal on both sides of the fiberglass. The part inside the filter was too large to be ingested into the engine. Today due to vibrational characteristics all of the rivets pulled through the outside door plate breaking the inside plate. As you would expect this part was large enough to cover most of the intake opening. All rivets are intact so no metal went into my engine.
At 1500 agl in climb out today almost total power loss. Boost pump on, switch tanks, check various mixture positions. No luck. Reduce throttle and got smooth engine. No more troubleshooting. Flew back to the field at about 40% throttle. Got the plane on the ground (luckily the grass strip I was flying from was only 3 miles). Nice landing.
http://i32.tinypic.com/x5dw0.jpg
My current plan is to build a full size aluminum plate on both the inside and outside the bottom of the FAB. The filter would actually sit on the inside plate and no plates or loose parts inside the filter circumference. The outside alt air door plate will also be drilled for rivets around the entire circumference (as you can see in the pictures the rivets do not go around the entire circumference) to make it more solid. Get engine dynamically balanced. Expensive part is to get repairs or replacement of the fuel servo since the 4 venturi air tubes were damaged by the loose plate striking them.
Andy
At 1500 agl in climb out today almost total power loss. Boost pump on, switch tanks, check various mixture positions. No luck. Reduce throttle and got smooth engine. No more troubleshooting. Flew back to the field at about 40% throttle. Got the plane on the ground (luckily the grass strip I was flying from was only 3 miles). Nice landing.
http://i32.tinypic.com/x5dw0.jpg
My current plan is to build a full size aluminum plate on both the inside and outside the bottom of the FAB. The filter would actually sit on the inside plate and no plates or loose parts inside the filter circumference. The outside alt air door plate will also be drilled for rivets around the entire circumference (as you can see in the pictures the rivets do not go around the entire circumference) to make it more solid. Get engine dynamically balanced. Expensive part is to get repairs or replacement of the fuel servo since the 4 venturi air tubes were damaged by the loose plate striking them.
Andy
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