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HARTZELL CLAW PROPELLOR For Sale

tdf

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RARE OPPORTUNITY • HC-C3YR-1A/C7690E with spinner. Robust propellor, proven reliability, with optimum aerobatic performance in the vertical. Excellent condition, no damage, chrome spinner. Last overhaul in 2011 at Hartzell factory. $35,000USD. Contact Todd. 306-313-6717. Owner - located Belleville, ON, Canada.
IMG-1649-1.jpg
 
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Dana

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Wow, must be some prop! Even the used price is substantially more than my entire plane, and over 50 times what I paid for a new prop for it.
 

race38

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When that prop hit the market 25? yrs ago it was $35K.
I've flown behind one that, went over on it's back in a taxi incident, was sent in for overhaul and they only inspected and returned to service.
Almost bullet proof. Smooth and powerful.
Price a Whirlwind 400 probably as much.
 

PittsDriver68

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I have some time in a Pitts S-2C behind that prop. Even at idle throttle it is still putting out thrust. A friend has a two blade Claw. Rare as Hens Teeth. Just need to get the pricing down to be competitive with MT.

Best of luck,

Wes
 
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Jean-luc

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Tdf
Just curious !! ..How much power and engine do you have for such propeller ?
 

Flybipe

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There is a SB on these props that is not widely publicized but its HC-SB-61-356. It requires inspection of the secondary blade shank windings. If the blades are found to be out of spec, Hartzell will repair them for free, but only until January 1, 2021. After that, if they are found out of spec, I believe your on your own to repair or purchase new blades. The inspection is done by measuring the blades with the prop disassembled. It might be worth checking that out if you haven't had it done yet before the offer from Hartzell expires - new blades are around $19K a piece last time I checked.
 
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wil780

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Have there been any incidents related to the issue addressed in that service bulletin?

A Hartzell rep just told me that all Claws manufactured before 2015 will fail the test. There's been a lot of hours on those props, some in much more severe service than mine (2550 for aerobatics, no gyroscopics), so I'm thinking I won't bother trying to get the blades to Hartzell before the deadline. Now that the "secret warranty" has been posted, there likely will be a very long backlog of blades waiting for modification, and I do want to fly next summer.

If my plane were certified I would make a different decision.
 

Flybipe

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I can’t speak to whether there have been any incidents related to this SB but I can tell you I had both my props complied with by a Hartzell factory authorized service center earlier this year and they both passed. There was no mention of a date-of-manufacture effectivity at the time, and I’m confident one of my props was manufactured before 2015. (2014 I believe.)

Regardless, if it were a serious flaw, it would have likely been issued as a mandatory SB or “comply within next xx hours of service” or if very serious, an AD would have been issued, so I’d tend to think your risk is low.

(I would not want to have to pay to replace these blades though, as it would exceed the value of the prop!)
 

PittsDriver68

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I would telephone Hartzell before making any assumptions about the backlog at their shop. Relatively speaking, there are not that many Claws out there.

Best of luck,

Wes
 

wil780

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There is one other issue probably worth mentioning since we're on the topic of these props.

I have the original, non-counterweighted model. It uses an oil pressure accumulator tank and a check valve between the governor and the prop to maintain oil pressure to the prop for a few seconds (maybe 10 or 15 - Hartzell couldn't tell me) after oil pressure in the main gallery drops. That is an imperfect solution for aerobatics. If there is a problem with the inverted oil system the engine likely will run a lot longer at minimal pressure than the oil in the accumulator will last. Plus, I've heard of at least one incident where a racer took off the accumulator because he wasn't planning on negative g. He destroyed the engine from overspeed and damaged the plane during the off-airport landing.

Hartzell really wants people to take these non-counterweighted Claws off aerobatic planes. I had a conversation with them about another issue and every second thought from them was directed at convincing me to sell the prop rather than the original issue. Apparently they have a liability issue because they sold a system that is imperfect and far from foolproof. They offered to convert my 2 blade prop to counterweights for approximately $20,000!

I explained to them that in addition to the accumulator I have an automotive oil pressure switch plumbed in parallel to the oil pressure sender that sounds a very loud horn when the pressure drops below 15 psi. I figure that if I have a problem with the inverted system that will give me plenty of time to pull the throttle and return to positive g before the tank runs out of pressure. They finally admitted that I was probably OK to continue using the prop, but clearly still didn't like it.

Consequently, I have a nagging worry that if I send the prop or even just the blades to the factory for compliance with the Service Bulletin I might never get it back.
 

TFF1

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That seems like a special case, although I have seen SBs that were ten years old turned into ADs just because it was easy for the FAA to do it without any extra work for the factory engineers. Can only Hartzell do the work or dan a prop shop do it?
 

Flybipe

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A prop shop can do the inspection - the prop does not need to to go Hartzell.
 

wil780

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The Hartzell rep I talked to said only the factory can modify the blade shanks to comply with the SB. However, he also said that all (now that I think about it maybe he said almost all) blades made before 2015 will fail the inspection, and there is at least one exception noted earlier.
 
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tdf

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The prop for sale will be sold with a fresh overhaul in Dec 2020 (HC-SB-61-356 will be complied with).
 

Billyto

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Mine was overhauled in 2016. Passed perfectly and the SB was already published in it's second revision.
By the way, I fly airshows no problem with that accumulator and a digittal EMS that shows a big warning if oil pressure drops bellow 50. Doing all kinds of stuff never had any problems.
Without counterweights you save a TON in weight in the nose and giroscopic forces. As someone mentioned that "racer" had his without counterweights to have better performance. Of course, without the accumulator it's is not going to work as we know now. Very few problems have been noted without counterweights and accumulator or an AD would be there. Before Hartzell mandated same spec propeller at Red Bull, non counterweighted was the desired choice. Know a guy who was offered a straight swap from a racer and declined because the hustle to change config.
Other thing, remember when Sean D Tucker lost all his oil pressure? The engine worked but barelly flew back to his base with WOT and 1000something RPMS. If I loose all oil pressure I rather have fine pitch that will let me fly slowly back to base with minimun throttle to avoid (if it can) size the engine..... If a pumped up Lyco can fly ten minutes at WOT/1000 something rpm/no oil pressure, sure should longer in better conditions.

By the way, if you go counterweighted, like in an MT, Whirlind, etc you will need an acumulator if you fly unlimited. Snaping in the vertical would feel like going to overdrive in an automatic car. You need that accumulator to help change fast the blades to coarse pitch.
 

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