Need a bulkhead (mine just self-destructed at 4k MSL; was over a field, no issues landing...nice pic, though)

[FlyBoyM20J]

The plane is a 1982 M20J, SN 24-1298.

I and a safety pilot were up for some approach work yesterday when we both heard a loud noise from the engine...no real vibrations (going along at ~25.5", 2550, 160 kts TAS, 4k MSL, VMC), but the noise got louder over perhaps 20 seconds such that I and my co-pilot agreed that it was real...and I was sure I had never heard it before.

It sounded like a chainsaw engine revved up and getting closer (growing louder, but constant pitch).

About that time, we could both smell a whiff of smoke.  I removed the hood (yeah, this was fun to figure out with that thing on right at the beginning), and there appeared to be a tiny bit of smoke coming from behind the spinner, so I immediately pulled power back, checked pressures, temperatures, JPI graphs, all good, and the noise lessened with lower RPMs.

I notified ATC and diverted to the field right below us, did uneventful landing in VFR conditions, and pulled the top cowl on the ramp for a closer look.  This is what we found...no other issues anywhere on the plane, no more oil on the gear doors than I'd expect for an hour of flight, etc.  And a fair bit of chewed up fiberglass stuff in the intake filter and at the oil cooler.

JPI engine data from this flight looks like any other recent flight. Engine unaffected, at least, in the couple of minutes that it was running between pulling back power and shutting down on the ramp.

So, looks like I need a new bulkhead.  Given my SN, this would be PN 680031-017.

Any leads?  I have already talked to Dave @ AirMods and he thinks he has one in his GA "warehouse".  But that's uncertain and he's not going there for a while.

Looks like I am going to need some fiberglass work, too.  The top cowl got a hole punched through it (see pic) and there's one on the opposite side but it is otherwise undamaged and assembles like it always did.  Bottom cowl has some minor damage.

Cheers,

Cliff

 

[Guest]

I’ve got a complete spinner and bulkhead assembly for a J model.

[FlyBoyM20J]

4 minutes ago, M20Doc said:

I’ve got a complete spark and bulkhead assembly for a J model.

Thanks, Clarence!  I saw your DM and will email you...enjoy vacation!

Cliff

[N201MKTurbo]

Wow. 
 

Just goes to show how tough those thin cowls are to take that kind of beating and stay in one piece. 

[M20F]

Nothing JB Weld can’t fix. 

[Fly Boomer]

11 minutes ago, M20F said:

Nothing JB Weld can’t fix. 

I recently saw a split spark plug nut "repaired" with JB Weld.  Right up there with using parts from the aviation aisle at ACE Hardware.

[DCarlton]

Wow.  Wondering if the plane had been in annual, would there have been any chance of detecting the pending failure before it happened.  Cracks around screws big enough to see for example... 

[FlyBoyM20J]

16 minutes ago, DCarlton said:

Wow.  Wondering if the plane had been in annual, would there have been any chance of detecting the pending failure before it happened.  Cracks around screws big enough to see for example... 

We'll never know...this was (in fact) to be the last flight prior to going on jacks for annual.  No evidence of cracks at the last oil change, either (30 hours ago), at least, nothing that caught my eye.

Annual under an IA's watchful eye might have caught it...I'd like to think so.

[OR75]

the machine screw that attaches the bulkhead to the bracket seems to be a different color and not a standard MS type screw with a shiny silver color

Or may be it is just the picture 

[FlyBoyM20J]

Update, 3 weeks later, it is fixed!  Thanks a million to Dave & Lisa at Air-Mods in NJ!  Perfect fit!  Flew home after the install and, if anything, there is less vibration now than at any time in the last couple of years. 

That said, I will have it balanced ASAP.

Thanks, also, to Clarence @M20Doc, who has a part and was going out of his way to help me on his vacation a couple of weeks ago.  The local mechanic where I got the plane stuck *thought* he had found a part right away so Clarence said go with my mechanic's find, but that turned out to be the wrong part. Meanwhile, Dave from AIr-Mods had had a chance to visit his Georgia location and brought this one back with him.

Thanks, not least, go to the local mechanic but I'm not sure he wants to be on the internet so I'm leaving his name and the field location out of this post.  He rocks, though.

Cliff

[carusoam]

Great pirep for Dave and Lisa at AirMods NJ!

Thanks for sharing the details!

Best regards,

 -a-

[skykrawler]

Looking at the damaged bulkhead it would seem the crack had been there a while.  Spinners are a #1 preflight item for me.