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Prop Field Approval

OLDCROWE

FRIEND
Meanwhile,...
So what would be the chances be of getting a field approval for a certified prop that has been STC'd for similar aircraft but not (yet) for your specific aircraft but it is in the slow process of being STC'd ?
 
I'm looking at Hartzel's Composite Top Prop for my 180 (IO-520D/300hp/2850 rpm).

The same shape in aluminum blades at 80 & 82" has been approved for a 180 with a IO-520D @ 300hp/2850 but not yet the composite blades. I understand from multiple sources that the composite prop has been successfully vibration tested in my desired configuration but due to an unrelated engine problem on the test aircraft completion of the STC has been delayed.

Talking with Hartzel's project manager for this prop at OSH I was impressed with what they offer in terms of warranty (including paint) through TBO.

I really need to re-prop for noise (got neighbors now) and its no secret that my MAC (88x3) sure barks even when pulled pack into the green on take off and it is getting a bit long in the tooth plus the CG help would be appreciated.
 
we USED to get field approvals on 84" Pawnee props on O-360 cubs...

but they quit, something about the vibration analysis we were using not being complete...
 
we USED to get field approvals on 84" Pawnee props on O-360 cubs...

but they quit, something about the vibration analysis we were using not being complete...

That one never made sense. How many years have we run that prop/engine/airframe combo, multiplied by all the aircraft equipped like that (just in Alaska) equals about a gazillion hours. But not enough data!

Web
 
Oldcrowe,

How about the MT? I would imagine its approved already, 2 and 3 blade. No BS hub AD's like many Hartzell's have. I have had 3 MT props on Husky's and really liked em, just a thought...

Kurt
 
Oldcrowe,

How about the MT? I would imagine its approved already, 2 and 3 blade. No BS hub AD's like many Hartzell's have. I have had 3 MT props on Husky's and really liked em, just a thought...

Kurt
I was headed that way until I looked at a new one that flew through a little rain going into New Holstein... it had no paint on the tips.
 
But Hartzel covers it under warranty, the quote was "if we put it on we guarantee it to stay on."
 
Did the MT have the new bigger leading edge? My 7 year old still looks like new but never been in rain.
 
I was headed that way until I looked at a new one that flew through a little rain going into New Holstein... it had no paint on the tips.

I just flew 2 hours solid in rain with my new one, NO issues. In fact, I have flown in a lot of rain with all 3 MT props with NO issues or one speck of paint coming off. MT's are BY FAR the most durable props I have ever operated.
 
OLDCROW. What is the model of the prop? Go to FAA.gov to look up the prop TC. At the bottom of the TC there will be a list of engines which are approved vibrationwise along with any limitations. Start there, then ask either your IA (or you do it) to talk nice to his PMI at the FSDO. There are noise requirements which must be met which can become the issue depending on the PMI. OR offer Hartzell the use of your 180 for the noise tests.
 
Kirby
Why don't you just cut 2" off your 88". It's legal I believe.
Lou
Lou I have thought about doing just that (would deffinately be the less expensive route) to just have the full inspection/rehab done and clip it in the process and go on. But what I don't know is how much quieter it would be, the only example I've flown is SJ's with a PPonk and 86X3 and while it has to be quieter with less diameter and less rpm, let's just say it doesn't whisper either.
 
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A local 185 with a 550 conversion had vibration issues with the MT. After lots of troubleshooting, time and money the McCauley was installed and no vibration and better performance.
 
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