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Prop Governor Analysis (please advise)

BruceMe

Well Known Member
I've been doing a lot of prop governor research as I'm about to convert an FP to CS. I have no affiliation or been induced in any way... Just pulling together a lot threads I've read on VAF.

The big names are (in order)

PSU 5000
MT
Woodward
Hartzell

Background... All the governors above are certified (tagged) except the PSU which comes in either certified or experimental (same part, no paper). They typically have a TBO of 2,400hrs or 6 years whichever comes first. I'm not sure if the 6yr timeout is critical or just what they worked out. Overhauls typically cost 2/3 the cost of new.

PSU 5000 - The trend in RV is definately PSU, it appears to be a better built part and has what appears to be a very good record with builders. It is about $400 more than the others new.

MT - While light and compact some more heavy duty users have had failures and it has caused some folks to swap out to PSU at 6 years.

Woodward - Older style, very reliable, a bit bigger and heavier, but not crazy. Repairs/overhauls are rumored to be expensive.

Hartzell - Not a ton of info here, they made a governor for the homebuilt market S-1-10, I can't find anyone who's using it.

Let me know if you think I'm off the mark on this analysis, I just wanted to have a thread for posterity.
 
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Among your list, two item to consider, the overhaul requirement and the ability to feather the pitch at low RPM. Six years/2400 for overhaul is a costly proposition which few will fly 2400 hours in six years. As I understood it, MT prop was made by Jihostroj and they only put their own tag on it. Also, much of the parts now are still being made by Jihostroj

http://www.propellergovernor.com/
 
I've been doing a lot of prop governor research as I'm about to convert an FP to CS. I have no affiliation or been induced in any way... Just pulling together a lot threads I've read on VAF.

The big names are (in order)

PSU 5000
MT
Woodward
Hartzell

Background... All the governors above are certified (tagged) except the PSU which comes in either certified or experimental (same part, no paper). They typically have a TBO of 2,400hrs or 6 years whichever comes first. I'm not sure if the 6yr timeout is critical or just what they worked out. Overhauls typically cost 2/3 the cost of new.

PSU 5000 - The trend in RV is definately PSU, it appears to be a better built part and has what appears to be a very good record with builders. It is about $400 more than the others new.

MT - While light and compact some more heavy duty users have had failures and it has caused some folks to swap out to PSU at 6 years.

Woodward - Older style, very reliable, a bit bigger and heavier, but not crazy. Repairs/overhauls are rumored to be expensive.

Hartzell - Not a ton of info here, they made a governor for the homebuilt market S-1-10, I can't find anyone who's using it.

Let me know if you think I'm off the mark on this analysis, I just wanted to have a thread for posterity.

I believe several of these are derivatives of a Jihostroj governer.

I have a Hartzell S-1-32 in my RV-10. It works as advertised. Van's has been sending out Hartzells for the last several years in the FWF kits.
 
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You don't necessarily need to rebuild at 6 years. It is perfectly acceptable, in my mind and on advice from a known governor shop, to have an "inspection and reseal". This will cost much less than a full rebuild.
In a full rebuild they replace parts, regardless of condition, and do dye penetrant inspections. You can judge what level of risk tolerance you have and decide the best path for you.

By the way, my governor was an MT label stuck over a Jihostroj governor. The rebuild shop couldn't yellow tag it as an MT as such so they peeled the label off and it is now a Jihostroj.

I have had no issues with it. 11 years and 750 hours. I had it rebuilt at 8 years and wish I would have just had the inspection and reseal done.
 
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