I own N6755P, PA24 (180) ser # 24-1884 with a Hartzell HC-92ZK-8D prop. The spinner developed cracks in 2010 and was repaired by Aero Support Engineering. We just found two more cracks. Should I send it back to Aero Support or buy a new one? If replace, what are the options and sources?

We put a TCB composite spinner on our Tomahawk and have had no problems with it. Any experience to share?

Carl,

I've been on this Forum for awhile now and haven't seen many posts on this subject - not saying it isn't a problem, just saying i haven't seen posts on it.

wrt my Twin, I found that the Hartzell prop instructions for attaching the backplate and spinner were not always followed so that might be something you want to check.

After working with my Mom, Marion Jayne Hartzell did bring out a thicker backplate for Twins so backplate cracking and therefore spinner cracking was dramatically reduced.

You might also look at the log books to see when the motor mounts were last changed. If not within a few years, they might need attention and be causing excessive vibration that is impacting the pro/spinner assembly.

Hope this gives you some places to look.

Carl,

If it helps, I have an original spinner in perfect condition that I would be willing to part with. I replaced my 1964 180's original prop a few years ago with a new "Top Prop" when the blades wouldn't pass inspection any more.

Pat Donovan

Hi Pat,

Don't want to hijack the thread but would you mind posting your thoughts on the new Top Prop for the -180. I assume you're meaning the Hartzell scimitar prop?

I'd certainly be very interested in your thoughts. Maybe in a new thread?

Cheers,

James.

James,

I believe there are now two versions. Our 180 has a Hartzell Top Prop that is not a scimitar blade. It was on our Comanche when we bought it so I can't really offer an opinion on performance as it is all I have known. It did get rid of the prop AD however.

I think they just started offering the scimitar blade for the 180 within the last year.

Michael

James,

To answer your question, my Top Prop is not scimitar. I flew the original prop for many years and was quite happy with it. Changing to the new prop did not involve any change in performance that I was able to detect. I don't like the yellow range from 2000-2200 as I used to occasionally use that range. Now I limit myself to 2300 as a normal. I do operate over square at times (like 24"/2300 rpm).

The new prop also required a new spinner and backing plate. My old spinner was polished versus painted. The new metal spinner had cracking problems when mounted on Mooneys (not Comanches) and was replaced by Hartzell under warranty TWO times as they attempted to correct the issue. Last annual I found the back plate had cracked. Called Hartzell and they replaced the back plate and sent a new composite spinner which makes THREE times for a new spinner. Got to say I am a fan of their warranty service.

Biggest issue with the new spinner is that it is very "pointy" and gets in the way when using the tow bar.

PatD

Pat, Was your metal top prop spinner the one with fillets or the one piece version with flanges formed in the blade holes? I have the one with formed flanges that I put on in 2009. I've not had any cracks yet, and deferred getting the composite replacement because I like the original better.

Thanks,
Steve

Steve,

The first spinner came with fillets that attached separately behind the blades. After attempting to use the fiberglass bulkhead supplied under warranty and intended to provide additional support to prevent cracking, the bulkhead started to spin inside the spinner and the whole thing was replaced under warranty for a shorter metal spinner that didn't have the fillets behind the blades. That was the one in use when the cracks developed at around 400 hours. I had dynamically balanced the prop early on.

Hartzell offered to replace the back plate under warranty and said the only way to prevent future problems was with the composite spinner which was again sent under warranty. So I opted for the composite spinner. I still have the metal one, so could presumably put it on if the holes align.

I also liked the polished metal spinner appearance better.

Pat

Pat,

Good information....thanks. I have the long metal spinner and will watch it closely. Without looking at the log, my guess is it should be coming up on about 300 hrs.

Steve