Does this look like a reasonable amount of paint damage for a 100h Hartzel CS prop after one flight in rain (and not really hard rain)... Both sides are similar, both blades as well. Thoughts?
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Rain damage to paint on prop blades
- Thread starter georgemohr
- Start date
Wow, I have flown in the rain and a few times in a really hard rain and never such thing happened. I can't tell if the visible gray is aluminum or the gray paint that is in the front portion of the plane but if aluminum it will need to be addressed for corrosion protection.
Was my partner's flight so I'll have to ask, but I'll guess 160 ktas for 1/2 hour of rain based on his description.
Well, if you prefer not to slow down then what do you expect?
I fly in rain with a composite anything from light to very heavy with a Sensenich composite. Never had paint stripping off it from 1/2hr of rain.
FORANE
Well Known Member
Is that 100 TTSN or 100 SMOH? If SMOH, who did the overhaul?
I experienced paint peeling off in sheets on a MT one flight through light rain after an overhaul by a shop in GA.
100 since new.
Call Hartzell.
Airspeed is one factor, but RPM makes a big difference. So does the type of paint, and if sand has eroded the LE of the blade already then it is even more susceptible to damage. At 2700 rpm the tip of a 74" prop is going 870ft/sec or about 600 mph w/o airspeed vector. A Diamond pilot friend said he drops rpm to 2200 for rain.
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Based on my limited experience, that’s a lot of paint wear for those conditions.
I assumed as much. Rain ablation on a wing leading edge might be airspeed, but those prop blades are moving much too fast for a few knots of forward speed to matter.
I'll document and open a ticket with Hartzell. Thanks all.
-G
When I said 'slow down' I meant both airspeed and RPM. I reduce RPM to 2100 in rain and slow down.
I experienced the same, from the same shop, twice. Never again.
In discussions with Peter M. of MT in Deland, he advised dialing the RPM back to something below 2300 when in rain. This was several years ago.
In more recent discussions with John. N. of McFarlane, he said they can hit the leading edges of MT props now with a pressure washer from close range with no adverse affects. due to improved paint technology. I've never tried that but I haven't had any issues since I had my MT overhauled in Deland.
I would be calling Hartzell if I was the OP.
FORANE
Well Known Member
Interesting, I also have not had any trouble since my last MT overhaul in Deland.
Some updates. Hartzell told us we are out of warranty (16 months) so no joy on that front. They also suggested this was "normal" erosion, even though I pointed out that 95% of this damage happened on one fight. They also implied that we washed the blades with an incompatible soap (didn't) and that we fly off of bad tarmac (don't).
Not a great outcome...
I guess we will have to pull the prop at annual this winter and have it refinished.
Not a great outcome...
I guess we will have to pull the prop at annual this winter and have it refinished.
That's a rather disappointing response to say the least.
To put it in perspective, my long out of warranty (years) Laversab 6300 P-S test box (which cost more than a new prop) was having an issue so I sent it to them fully expecting a large repair bill, they did a full upgrade to the latest version, new pump and recalibration.... for ZERO dollars!
They also paid for shipping both ways, now that's what I call customer service!!!!!!!!
MidwestMan
Well Known Member
This is what prop damage from normal wear and tear actually looks like. https://www.kitplanes.com/maintenance-matters-22/
Also note in that kitplanes article, it recommends SANDING the paint off because when it's been painted correctly, that's what it takes to remove.
The picture posted looks like the paint was defective and failed to adhere to the blade. Paint only comes off in big flakes like that when there is a bonding issue.
Companies aren't supposed to be able to give a customer a factory defective product and then say it's out of warranty when they find the defect. I had the same paint peeling issue on a new prop that I purchased from a major company. They initially said they wouldn't pay for anything and denied it was a problem. I informed them that they owed me a defect free prop based on the warrant of implied merchantability, and they eventually admitted it was their problem to take care of.
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Yeah, nice that it hung on just long enough to exceed that warranty also... <--- bitter!
MidwestMan
Well Known Member
Warrant of implied merchantability lasts 4 years in the US. I believe they owe you a new prop. https://www.ftc.gov/business-guidance/resources/businesspersons-guide-federal-warranty-law
Yeah but GL to me for getting that 
I'd be happy with just covering the refinish job.
I'd be happy with just covering the refinish job.
Sensenich covered some things outside of my warranty period and repaired them free of charge. There are good manufacturers out there.
George,
Hartzell defines "normal" erosion in its HARTZELL PROPELLER OWNER'S MANUAL 115N as."Normal erosion (sand-blasted appearance) on the leading edge of the blade is permitted and does not require removal before further flight."
Inspection and Check - Page 5-3 - 1,B,(1), (a)
What you are seeing is paint adhesion failure.
Hartzell is blowing smoke at you; hoping that you'll go away. Hartzell is now under private equity firm ownership.
Since exposed aluminum on propeller blades invites corrosion, it is a safety concern. Please consider submitting a Form FAA 8010-4 - Malfunction or Defect Report https://www.faa.gov/documentLibrary/media/Form/FAA_Form_8010-4_.pdf
Post #21 and this^: I would be tempted to let Hartzell know that the law is on your side (#21) and that you are filing a 8010-4 with the FAA. That might put a fire under their resistant butts.........George,
Hartzell defines "normal" erosion in its HARTZELL PROPELLER OWNER'S MANUAL 115N as."Normal erosion (sand-blasted appearance) on the leading edge of the blade is permitted and does not require removal before further flight."
Inspection and Check - Page 5-3 - 1,B,(1), (a)
What you are seeing is paint adhesion failure.
Hartzell is blowing smoke at you; hoping that you'll go away. Hartzell is now under private equity firm ownership.
Since exposed aluminum on propeller blades invites corrosion, it is a safety concern. Please consider submitting a Form FAA 8010-4 - Malfunction or Defect Report https://www.faa.gov/documentLibrary/media/Form/FAA_Form_8010-4_.pdf
Keep those FAA 8010-4 - Malfunction or Defect Reports coming. This problem might then be addressed proactively by Hartzell to avoid dealing with an Airworthiness Directive.
Props can be refinished on the aircraft. See Taking Care of Your Metal Prop I touch up my prop every two years or so.
That sucks that Hartzell will not offer a re-paint, or at least a discount if flown to their shop in Piqua for touch-up on that. To me it does look to be some adhesion problem by the picture. You do not show your location. I recommend that when the repair is done that the proper Sherwin Williams "Polane" paint is used. If prepped correctly will last for years and years. Any good propeller shop should/will be able to supply the repaint service. We call it a "Perfume" at the prop shop where I work. Minor abrasion is removed, cleaned, alodine bare aluminum, scuff of existing paint and re-coat of the factory Polane paints. We add grease per 115N, and static balance is also performed while we have it. That is the proper way to address this issue IMO. Once back on the plane, fly it a few hours, top off with grease per 115N and then a dynamic balance will make it as smooth as can be.
There is some good general prop advice in this AC (Most pics taken at our shop many years ago):
There is some good general prop advice in this AC (Most pics taken at our shop many years ago):
Just a guess, but suspect the "old hartzell" is long gone. They were bought by a private equity firm and this type of behavior is pretty common, as the goals change purely to short term profitibility. If they are successfull in buying most of the competitors as well (already own WW), This behavior is no longer a reason not to buy, as all the options will be the same.
My MT looks like the original photo after a slow ride in the rain. MT has leading edge SS sheath. SS is notorious hard to have paint adhere. MT told me that they changed their paint in 2019 to get better results. Mine is a 2019 so didn’t work for me. At OSH , MT offered some touch up paint …… I’m still waiting on it …
