Perhaps the title is a bit melodramatic, but I thought this was worth sharing in the interests of safety...
A month ago I bought an older (1988) RV4. It has so far been a total joy to fly, including a 24.1-hour trip to Oshkosh and back.
Today I had planned a flight from LA to Seattle. Run-up checks were fine. About five seconding into the takeoff roll, tail up, just ready to lift, the engine started to misfire horrendously. I decided it was best not to continue into the air.
The airport is I fly from is surrounded by city in every direction. Had this had happened during the climb-out, I may not be typing this now.
I taxied back to my hangar, but the aircraft was running terribly with a gigantic misfire / loss of power at higher RPM.
I suspected a stuck float. However, on removing the air box to peek up inside the carb, discovered that a cone-shaped part inside had come unglued from the base. As high RPM, it was obviously being sucked up into the carb venturi, blocking the flow of air and causing severe loss of power.
I had opened-up the air box to replace the filter a few days ago. I was aware that the cone was in there, but it didn't cross my mind that it was only glued in place. Obviously the glue had failed. It could have killed me.
I have removed the cone from the box until I can work out why the builder put it in there. The engine appears to run fine without it.
Just wanted to post this in case anyone else has a similar setup in their aircraft - in short, pull the cone out, or make sure there are some good screws holding it in place.
Nice to see my wife and young boy tonight. Booked for Seattle on an airliner tomorrow morning.
A month ago I bought an older (1988) RV4. It has so far been a total joy to fly, including a 24.1-hour trip to Oshkosh and back.
Today I had planned a flight from LA to Seattle. Run-up checks were fine. About five seconding into the takeoff roll, tail up, just ready to lift, the engine started to misfire horrendously. I decided it was best not to continue into the air.
The airport is I fly from is surrounded by city in every direction. Had this had happened during the climb-out, I may not be typing this now.
I taxied back to my hangar, but the aircraft was running terribly with a gigantic misfire / loss of power at higher RPM.
I suspected a stuck float. However, on removing the air box to peek up inside the carb, discovered that a cone-shaped part inside had come unglued from the base. As high RPM, it was obviously being sucked up into the carb venturi, blocking the flow of air and causing severe loss of power.
I had opened-up the air box to replace the filter a few days ago. I was aware that the cone was in there, but it didn't cross my mind that it was only glued in place. Obviously the glue had failed. It could have killed me.
I have removed the cone from the box until I can work out why the builder put it in there. The engine appears to run fine without it.
Just wanted to post this in case anyone else has a similar setup in their aircraft - in short, pull the cone out, or make sure there are some good screws holding it in place.
Nice to see my wife and young boy tonight. Booked for Seattle on an airliner tomorrow morning.
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