MT Hairline Crack

Brambo · #1 03-15-2010, 10:22 PM

While wiping down the prop after a flight the other day I discovered a hairline crack on one blade. It starts at the tip and propagates toward the hub, is about 3/8" long and goes all the way through the blade from front to back. The prop only has 76 hrs on it and I'm currently in discussions with MT as to if its covered under warranty or not. My question is, is this a common occurrence for an MT prop?

Bob Brown · #2 03-17-2010, 12:47 PM

Is it a metal blade MT prop or is it a composite?

MattSR · #3 03-17-2010, 07:47 PM

Wow - 76 hours and theres a "discussion" over weather or not its covered by warranty..?

Have a heart MT!

Capflyer · #4 03-18-2010, 05:26 AM

My experience with MT over warranty repairs on my RV7 were not positive. They were not good with the shop either. I had the MTV15 aluminum prop that needed to be re-sealed twice, the first time in less than 100 hours. It took many emails to the GM (who did respond by the way) to get them to cover it. Then they told the shop to do it while still mounted on the plane! Of course the shop had to remove the prop to do the work. Then MT said they would not cover the prop removal and remounting.... but in the end they did. The shop is an authorized MT repair and assembly shop, Sensenich Propeller in Lancaster, PA (I highly recommend them...they are excellent).

I know others have had great experiences with MT but mine was such that it would be close to impossible to convince me to purchase another one of their props. With so many other companies out there that care about their customers enough to stand behind their products, why bother with those that don't, no matter how good their product may perform.

Brambo, if you are still having warranty issues with them contact the VP/GM:
Martin Albrecht
Vice President / General Manager
martin.albrecht@mt-propeller.com

Steve Sampson · #5 03-18-2010, 07:23 AM

My experience is that they are very concerned to make it 'right', but I am dealing with the factory.

At perhaps 50 hrs I sent a photo of a few hairline cracks which I had spotted in each blade, asking about safety. Their reply was, not a safety issue but cosmetic:; cracks in the paint and filler.

They asked for the prop back, replaced the blades and picked up the shipping costs. It was back in a few days.

Brantel · #6 03-18-2010, 07:57 AM

They can say what they want about cracks but I take any crack in a prop way more serious than a cosmetic issue!!!!

Lose a part of a blade and you have about .1 seconds to react before you might lose your engine mount and engine.

9GT · #7 03-18-2010, 08:02 AM

On the Cozy MKIV I helped build, we put a MT 3 blade composite C/S on an IO-360. At just a little over a year and 126 hours, we noticed that all three blades had a hairline crack in the nickel leading edge that wrapped around both sides. All were "about" 5 inches from the tips of the blades. MT first thought that it would be warranted, but it ended up costing my buddy $2000 to repair. They also replaced the hub bushings to the latest style. Don't know if that was the cause of the cracks or not but it was done. It was an easy decision for me to order the standard 2 blade Hartzell for my -10. MT sure is a gorgeous prop though!

Steve Sampson · #8 03-18-2010, 08:43 AM

Quote:

Originally Posted by Brantel

They can say what they want about cracks but I take any crack in a prop way more serious than a cosmetic issue!!!!

Lose a part of a blade and you have about .1 seconds to react before you might lose your engine mount and engine.

Brantel, I think they probably know a thing or two about props and how to distinguish between the structural and cosmetic issues. Although I asked about safety, the position/direction of the cracks made no sense to me on my prop as a structural issue, which they confirmed.

Interestingly I saw a photo of an MT that had lost a bit in a bird strike. I imagined it would have been really bad to fly, but the pilot did not know he had lost anything 'til he landed, if I remember correctly. I guess the outer ends weigh very little on an MT.

Brambo · #9 03-18-2010, 09:34 AM

I'm waiting for American Propeller (Redding,CA) to pick up the prop. They said they would fight MT about the warranty for me.

Interestingly, this blade also has the "cosmetic" cracks that run vertically. They developed early on and when I called about them I was told the same thing "not to worry". I can't help but wonder if the stresses that caused the cosmetic cracks have also caused this real crack.

svennijo · #10 03-18-2010, 09:03 PM

I have seen cracks on a Cessna 175 with a Lycoming O-360 and the MT. A friend of a friend lost one of the leading edges on a experimental super cub with less that 5 hrs on it I believe. It is disturbing. I have heard of mixed results with how MT handled it, all ended up being warrentied, but some not with out some discussions.
I think that they have resolved the issue by adding some extra strentgh at the tips now from what I have heard. The props really work well on our float planes and we have not had problems with the more recent ones.
But I have defiently heard of a few of the same problems from good friends that you are having. I think MT will cover it.