Propeller Replacement - Mooney Missile

[Seth]

I need some advice from the MooneySpace experts:

I'm leaning toward 4 blade MT but don't want cruise speed loss.  Would love real examples from Ovation and Eagle owners who have replaced their props with the 4 blade MT.

I'm replacing my Mooney Missile full feathering prop with:

1.  Exact same prop from Hartzell - 75 inch full feathering scimitar three blade

2.  MT 4 blade composite non-feathering 74 inch 

3.  Hartzell 75 or 76 inch non-feathering three blade

I will write up a longer email once everything is done with my insurance claim, however at Oshkosh I was marshaled into an area of mud and my prop was destroyed.  The engine did not stop, however there was a reduction in RPM, and EAA's insurance policy is covering a new propeller, engine tear-down, and ancillary costs.  Again, I want to keep this thread on point with just the propeller replacement suggestions/recommendations.   I will complete a full write up for everyone as to how the EAA has been stand up in covering this as I was marshaled into a non-suitable area for taxi, the help from the Mooney Community (notably Alan Fox, Don and Paul Maxwell, Freeway Aviation, Myers Aviation, Byron, Ken Knop, Ken Yale, Chuck Swim, Erik Bolt, Ron, and others has been humbling - thank you to all).  

Again, let's keep this propeller focused - I want opinions, suggestions, real data, anecdotal, everything to help me make a decision.  Some people I've spoken with have given me a lot of good information - I just have not yet made a decision (life got in the way a bit) but I need to make that decision very soon.

1.  Exact Same Prop as what's on there:  Full feathering Hartzell 3 scimitar three blade 75".  Aircraft should perform the same.  

-Heavy nose

-Prop feathers if prop governor fails

-Better glide distance should engine fail at altitude as I can feather the prop:  15:1 glide ratio

-Only prop on the STC, no FAA paperwork required, only 45 or so ever made, no used examples available

-Hartzel can have it manufactured for me in 4-5 weeks - they have the parts in stock

 

2.  MT 4 Blade non-feathering 74" prop:

-Lighter - big issue with Missile and Rocket conversions - will lighten up the nose 30+ lbs.

-Lighter - energy to rotate the prop now goes into thrust

-Better CG - moves CG after just a bit which will allow the airplane to use less tail force, thus less drag when flying fast, hence ever so slightly increasing speed.

-Compound blade to the hub - better cooling, maybe a tad of ram air into air inlet

-1 inch better prop clearance and less wight on nose for less likely chance of prop strikes in future

-Better takeoff thrust, better initial climb

-Faster RPM changes

-Smoother, less vibration, less "thumps" as the thrust is now on 4 blades instead of three

-Non-feathering - removes the governor oil loss problem

-Not as good glide in an engine out

-Loss of speed in teens.  The normally aspirated engine (300HP IO-550)

-Loss of cruise speed at 6,000 - 10,000 feet? Unkown - this is my BIG WORRY

-MT overhaul intervals and other problems from before (delamination, bubbles, paint peeling).  I'd move forward with the Nickel leading edge which has many benefits and since their last two years of using a cat scan or MRI machine, they are discarding bad wood for the core before it even gets manufactured.  Many of their issues are behind them, but I still want to know the horror stories.  The nickel leading edge smallest three blade is 77 inches for this engine which is too long.3.  

 

3.  Hartzell 75 or 76 inch non-feathering three blade

-Removes the full feathering weight off the nose.  So lighter than the standard Missile prop.  If I can get the same blades 75" as the Missile prop it would preferred off the 76 inch current Mooney prop, but that will lessen prop clearance.  Will still give a little weight off the nose compared to stock prop.

 

I'm leaning toward MT 4 blade.  I was leaning away from it due to the anecdotal speed loss but then spoke to a Mooney Ovation driver who got one and has data to show he picked up may a knot or two, did not lose speed, runs cooler, and has better runway performance and climb.

The Missile already has great climb and is fast.  I could simply replace with the same Missile prop.  But, I don't need the full feathering mechanism.  Erik Bolt and I have talked tremendously about the handling of the lighter nose which makes a huge difference.  I also don't want to be scared taxing at Oshkosh for a similar issue in the future.  So a lighter nose, less nose compression, and the extra inch clearance are huge to me.

Most important is the cruise speed loss.  I don't mind losing a few knots above 12,000 feet.  I don't go there enough, and I will for a push (tailwind) or to get over weather.  Otherwise, I'm in the 6,000-9,000 range most of the time when flying.  Will I lose speed here?

Tests have shown on a normally aspirated Cirrus you lose speed once over 13,000.  However they are more draggy to begin with. So even if it start losing speed at 11,000 on a Mooney . . . how low does that go?

Any first hand experience or stories please provide information.  I need to make a decision.

And yes, it would be the first and only Missile with a 4 blade.

 

Thanks!

 

-Seth

 

 

 

 

[MIm20c]

The missile and rocket have a nose weight disadvantage IMO. This is why many will not fly to areas where long grass taxi journeys are necessary. The MT prop would be my first choice to reduce the cantilevered weight off the front wheel. The rest of the pros and cons are irrelevant, again IMO. 

[Niko182]

Remember that your vertical speed is also going to increase. Less time climbing at the lower airspeeds will probably make up for for the 1 or 2 knot loss at cruise speed. Benifits also include shorter takeoff roll and landings which would make the plane more capable.

[carusoam]

Consider the three variations of TopProp

thick

thin

composite

 

I went with thin... higher performance, less weight....

Composite wasn’t available at time of purchase, not even the MT...

If most of your flights include a climb to 12.5k’ the four blade isn’t going to be so bad as far as drag goes...

Best regards,

-a-

[KSMooniac]

I'm in a 77 J non-missile and electively upgraded to an MT 9? years ago to get weight off the nose and reduce vibrations. I'm still very happy with the decision and would do it again.

 

If I had a Missile or Rocket it would be the first upgrade I'd make, unless there was no engine monitor. Then it would be the second.

 

I don't think you'd be disappointed with the MT option.

 

I'm glad to hear the process is treating you well re: EAA. I figured you'd be SOL. Looking forward to your final report.

 

Sent from my LG-US996 using Tapatalk

 

 

 

 

[FoxMike]

I put an MT (4 blade) on my Bravo a couple of years ago.  I went for the nickel steel leading edge.  I could not be happier.  The only downside is that it will probably take months for MT to fill the order.  You could still get the OSH discount (10%) if you order now.

[Guest]

Does the Missile STC limit you to a feathering propeller or can you go non feathering?

A client of mine has 4 blade MT’s with nickel leading edges on his C340.  The props were removed and the blades repainted due to paint peeling behind the nickel.  Now the new paint is peeling, not a happy situation.

Clarence

[KSMooniac]

My original MT paint peeled as well. When my prop was new, they brought the paint up and over the stainless leading edge and very near the front, leaving an exposed paint edge to hit the air and rain. Really awful design detail that most aircraft companies prohibit.

When it was repainted, I asked that the paint stop at the back of the stainless or the stainless be installed after paint, but was told they can't do it that way. I did convince them to stop the paint as far back on the stainless as possible, and that has held up much better. Push for the repaint to leave that paint as far aft as possible.

Sent from my LG-US996 using Tapatalk

[Seth]

1 hour ago, FoxMike said:

I put an MT (4 blade) on my Bravo a couple of years ago.  I went for the nickel steel leading edge.  I could not be happier.  The only downside is that it will probably take months for MT to fill the order.  You could still get the OSH discount (10%) if you order now.

I have that built in for talking to them at Oshkosh.  Best time to have anything break where you need a deal is . . . Oshkosh 

 

except for AOG.  

Edited August 26, 2019 by Seth

[Seth]

1 hour ago, M20Doc said:

Does the Missile STC limit you to a feathering propeller or can you go non feathering?

A client of mine has 4 blade MT’s with nickel leading edges on his C340.  The props were removed and the blades repainted due to paint peeling behind the nickel.  Now the new paint is peeling, not a happy situation.

Clarence

Clarence - how long ago did your client purchase the props?  Evidently the newer harder paint formulas have addressed this but I want to make sure that this was not a new new prop, as that is something I’m concerned of.  

Especially since it’s with nickel leading edge.  The stainless steel has many instances of the peeling.  I’m not aware of as many nickel leading edges with the problem.

-Seth

[Seth]

5 hours ago, MIm20c said:

The missile and rocket have a nose weight disadvantage IMO. This is why many will not fly to areas where long grass taxi journeys are necessary. The MT prop would be my first choice to reduce the cantilevered weight off the front wheel. The rest of the pros and cons are irrelevant, again IMO. 

That is one reason I’m really considering replacing with the MT 4 blade.  The 3 blade would be perfect but the shortest 3 blade Nickel leading edge is 77 inches.  Mine is 75 now and the 4 blade is 74.  I could go stainless steel but everyone at MT is suggesting the Nickel leading edge for numerous reasons including wear and paint peeling.

 

[Seth]

5 hours ago, Niko182 said:

Remember that your vertical speed is also going to increase. Less time climbing at the lower airspeeds will probably make up for for the 1 or 2 knot loss at cruise speed. Benifits also include shorter takeoff roll and landings which would make the plane more capable.

Agreed.  However the Missile already has excellent runway and climb performance.  This will make it that much better.  Faster climb to cruise speed should indeed negate a knot or two or three loss.

The aft CG may make zero speed loss or maybe even slight gain in the 6,000-9,000 range in really targeting.

-Seth

[Seth]

5 hours ago, carusoam said:

Consider the three variations of TopProp

thick

thin

composite

 

I went with thin... higher performance, less weight....

Composite wasn’t available at time of purchase, not even the MT...

If most of your flights include a climb to 12.5k’ the four blade isn’t going to be so bad as far as drag goes...

Best regards,

-a-

Good advice.

Most of my flights are step climbs due to ATC up to 5,000-9,000.  

I rarely fly above 12,500 and will accept speed loss there as it’s to clear weather OR go on O2 for a push of tailwinds (or traveling to the west coast - last accomplished before marriage and kids in 2013).

Non turbo - Missile.  IO-550 normally aspirated.

-Seth

[Seth]

4 hours ago, KSMooniac said:

I'm in a 77 J non-missile and electively upgraded to an MT 9? years ago to get weight off the nose and reduce vibrations. I'm still very happy with the decision and would do it again.

 

If I had a Missile or Rocket it would be the first upgrade I'd make, unless there was no engine monitor. Then it would be the second.

 

I don't think you'd be disappointed with the MT option.

 

I'm glad to hear the process is treating you well re: EAA. I figured you'd be SOL. Looking forward to your final report.

 

Sent from my LG-US996 using Tapatalk

 

 

 

 

EAA has been good to deal with so far.

I’ll include this in a future write up but since this occurred under marshal, I’m 100% covered by the EAA policy.  

-Seth

[Seth]

2 hours ago, FoxMike said:

I put an MT (4 blade) on my Bravo a couple of years ago.  I went for the nickel steel leading edge.  I could not be happier.  The only downside is that it will probably take months for MT to fill the order.  You could still get the OSH discount (10%) if you order now.

It is a long lead time.  Airplane will be out of annual so I ferried it to my Mooney Service Center and that’s where she is now with no prop.

The Bravo, TLS, Acclaim, SR-22T, Rocket - all the turbos the MT wins.

Its the Ovation and regular SR-22 where up high the additional drag with lower MP is a problem.  My chief concern is a few knots of loss in cruise in the 5,000-10,000 range.

Glad you’ve enjoyed it on the Bravo!!

-Seth

[Seth]

1 hour ago, M20Doc said:

Does the Missile STC limit you to a feathering propeller or can you go non feathering?

A client of mine has 4 blade MT’s with nickel leading edges on his C340.  The props were removed and the blades repainted due to paint peeling behind the nickel.  Now the new paint is peeling, not a happy situation.

Clarence

Many Rockets have been converted.  The person I’m working with at MT would take care of the paperwork to change the Missile Governor to non feathering.

Mine would be the first Missile.

 

-Seth

Edited August 27, 2019 by Seth

[Seth]

1 hour ago, KSMooniac said:

My original MT paint peeled as well. When my prop was new, they brought the paint up and over the stainless leading edge and very near the front, leaving an exposed paint edge to hit the air and rain. Really awful design detail that most aircraft companies prohibit.

When it was repainted, I asked that the paint stop at the back of the stainless or the stainless be installed after paint, but was told they can't do it that way. I did convince them to stop the paint as far back on the stainless as possible, and that has held up much better. Push for the repaint to leave that paint as far aft as possible.

Sent from my LG-US996 using Tapatalk
 

This is the other stuff I’m worried about.  Thank you for sharing your experience.  The nickel leading edge is wider and the paint line further away from the prop edge.  It’s still a concern of mine even though MT says it’s not a problem anymore.

[FoxMike]

For whatever this is worth the paint on my prop blades is not peeling.  A friend put an MT on his Arrow about the same time I put mine on.  His blades are getting nicked up after 75hrs or so.  My blades have several hundred on them and they are smooth as a babies butt.  I would not go with the stainless.  BTW I ordered right after OSH and the prop arrived in the US right after Christmas.  Also, the climb rate is noticeably better and the cruise is the same.  Takeoff is shorter.  Best reason to buy is the much quieter, smoother  performance.

[Seth]

3 minutes ago, FoxMike said:

For whatever this is worth the paint on my prop blades is not peeling.  A friend put an MT on his Arrow about the same time I put mine on.  His blades are getting nicked up after 75hrs or so.  My blades have several hundred on them and they are smooth as a babies butt.  I would not go with the stainless.  BTW I ordered right after OSH and the prop arrived in the US right after Christmas.  Also, the climb rate is noticeably better and the cruise is the same.  Takeoff is shorter.  Best reason to buy is the much quieter, smoother  performance.

Thank you.  This helps!

-Seth

[Guest]

10 hours ago, Seth said:

Clarence - how long ago did your client purchase the props?  Evidently the newer harder paint formulas have addressed this but I want to make sure that this was not a new new prop, as that is something I’m concerned of.  

Especially since it’s with nickel leading edge.  The stainless steel has many instances of the peeling.  I’m not aware of as many nickel leading edges with the problem.

-Seth

Hi Seth,

The props were bought about 18 months ago,  I’ll check his logs to confirm.  My own MT on my Comanche has stainless leading edges and has only minor paint chipping after 6 years.

Clarence

[mike_elliott]

12 hours ago, Seth said:

I have that built in for talking to them at Oshkosh.  Best time to have anything break where you need a deal is . . . Oshkosh 

 

except for AOG.  

Well, Dirk Vander Zee had a solution for that at the Mooney exhibit for you  Including a rather fat discount!

 

[aviatoreb]

14 hours ago, M20Doc said:

Does the Missile STC limit you to a feathering propeller or can you go non feathering?

A client of mine has 4 blade MT’s with nickel leading edges on his C340.  The props were removed and the blades repainted due to paint peeling behind the nickel.  Now the new paint is peeling, not a happy situation.

Clarence

Huh?!  My MT with nickel treatment is not experiencing any peeling - 4 years on.  And as you know the C340 even has the identical engine as the rocket.

Edited August 27, 2019 by aviatoreb

[aviatoreb]

2 hours ago, M20Doc said:

Hi Seth,

The props were bought about 18 months ago,  I’ll check his logs to confirm.  My own MT on my Comanche has stainless leading edges and has only minor paint chipping after 6 years.

Clarence

Right - paint chipping as we know is different from paint peeling from kicked up fod.  The nickel is supposed to address paint chipping, and it does, by more thoroughly covering leading edges.

Anyway as I said, knock on wood, but so far so good with my MT with nickel coating.

[aviatoreb]

Seth ... all I have to say is .. don't go even longer.  :-). Clearance gets smaller and smaller obviously.

Aside - last Friday I dropped my son at Syracuse airport and as it turns out - I got a flat tire upon taxiing from the runway to the fbo.  So not a landing flat.  Not an exciting event.  But it went from full enough air that I noticed nothing and nothing when I got out and the line guy didn't notice anything when he chalked it.  But 10 min later when I was pre-flighting to go...100% flat rim sitting on the ground (in the tire) and prop lowered to the ground.  And I was thinking how much lower that would be with the original prop.

Double aside - I need to start carrying a spare tube - a simple tire repair is VERY expensive at a large airport serving mostly jets....

[Seth]

5 hours ago, aviatoreb said:

Seth ... all I have to say is .. don't go even longer.  :-). Clearance gets smaller and smaller obviously.

Aside - last Friday I dropped my son at Syracuse airport and as it turns out - I got a flat tire upon taxiing from the runway to the fbo.  So not a landing flat.  Not an exciting event.  But it went from full enough air that I noticed nothing and nothing when I got out and the line guy didn't notice anything when he chalked it.  But 10 min later when I was pre-flighting to go...100% flat rim sitting on the ground (in the tire) and prop lowered to the ground.  And I was thinking how much lower that would be with the original prop.

Double aside - I need to start carrying a spare tube - a simple tire repair is VERY expensive at a large airport serving mostly jets....

Sorry you dealt with the flat!!!  Had that happen to me on a Part 135 leg in a Cirrus.  Felt odd on landing, went flat once parked. 

Yes - a tube could make a lot of difference at a large field that does not cater to the piston crowd.  

I’ll make my decision very soon.  I’ll likely start another thread with color suggestions and some pics even though my wife and kids will help make the selection.

-Seth