Thread: Motor wound up.
View Single Post
  #3  
Old September 23rd 10, 01:31 AM posted to rec.aviation.homebuilt
Bob Kuykendall
external usenet poster
 
Posts: 1,345
Default Motor wound up.

On Sep 22, 12:21*pm, stol wrote:

This is from Reno air races.

About 8 seconds in the prop leaves and a second later you can hear the
motor rev up to god only knows how many RPMS.

http://www.youtube.com/watch?v=DhyEn...layer_embedded


Kevin wrote about this episode in his blog:

http://www.kevineldredge.com/Network...ing.....htm l

http://www.kevineldredge.com/Network..._Shape!!!.html

http://www.kevineldredge.com/Network...ensive!!!.html

And for once, the comments (so far) on YouTube seem to be pretty
accurate. The sequence as I understand it was:

1. The aluminum AN fitting on the accessory case where the hose from
the oil cooler connects broke.

2. Oil pressure went to zero.

3. The hydraulically-controlled constant-speed prop went to flat
pitch.

4. The engine overrevved. Way over.

5. The #5 rod and nearby counterweight broke and came through the
crankcase, seizing the motor.

6. The blades broke from the hub, and the prop extension broke from
the crankshaft.

Also, sometime during this sequence, the motor thrashed around enough
to break three of the four mounting ears from the back of the case.

7. Kevin flew the airplane, kept it under way and under control, and
did a fantastic job of reeling it back in from way over yawning abyss.

Thanks, Bob K.