MT Propeller

[FoxMike]

Back in the fall, a thread was started about an MT Propellers.  Back then I had one on order for my Bravo.  I promised I would give a pirep when I got it installed.  I ordered the prop right after OSH and it arrived about Christmas.  I needed to help a friend in Titusville so I decided to stop in Deland and have them install and balance the prop.  Long story about install but I will save that for another day.  Since the install I have been to KTIX, M54 (Nashville) and back to Denver and done some local flying.  My impressions so far are

The prop (a four blade) is extremely smooth.  One reason I wanted to do this is that after 3.5 hours behind the Mc Cauley I needed to get on the ground for a spell.  The vibration was fatiguing and I often do long trips and I need 4-4.5 hour legs.  On the way home from Florida I did 4+ hour legs without difficulty.

The four blade MT is about 2" shorter than the McCauley.  It makes the cabin much quieter.  In fact I am very comfortable flying without a headset.  Since I like background music I still wear the headset a lot.

I found takeoff runs shorter and the climb rate better.  I also found I need to keep the taxi RPM down to 800 or lower or get going to fast.  

Landing is different, I think due to blade drag and the lighter prop.  The airplane seems to float less and decelerates faster which I rate as a positive factor.  I find I can hold the nose up longer as the tail has less weight to lift.  I have not put this to the ultimate test as yet.  The test will be a full load of fuel and two fat boys in the front seats.  The Bravo now handles much more like a K model.

The ride in turbulence is a little less desirable than it used to be.  With the heavy prop. the Bravo would really plow through the bumps.  It now bounces a bit more.

Cruise speed I am still working on.  I normally use 28/2300 and a fuel flow of 15.5. When the MT was set to that power I got the same indicated airspeed at lower altitudes (under 10K).  Since the prop is shorter I tried 29/2400 and found that the fuel flow was higher and the plane was a little faster and the gas mileage only decreased 3%.  I also tried 32/2200, fuel flow about 17.5gph.  The result was a good 5% higher indicated over the McCauley and the gas mileage was about the same or a little better.  The percent power however is 81%.  

When the weather gets warmer I will get an idea if the engine cooling is improved.  I think it might be.  

Well that is about as much as I have observed so far.  I see improvement in all the areas that I deemed important when I ordered the prop.  Not large improvements but certainly worthwhile improvements. The only potential problem is that to pour enough TKS fluid over the prop blades they increased the flow which seems to cheat the flow to the wings.  I only flew in a little ice so I need to evaluate this a little more.  One other thing I have found more difficult is trying to install the lower cowling.  A few more practice sessions may improve my skill at this.

 

[KSMooniac]

I think the smoothness is that best aspect...that is good for airframe and panel components and of course fatigue reduction for the meat on board.

Post a pic!

Sent from my LG-US996 using Tapatalk

[FoxMike]

Here we go 

[aviatoreb]

Nice!

 

[carusoam]

FM,

Your going to want to post T/O run and climb rates too....

The Bravo doesn't naturally have a short T/O run like the 310hp O...

But, the four blade MT, has got to have great acceleration and climb rate to the Ozone layer! 

We have a time to climb thread around here somewhere...

Best regards,

-a-

[aviatoreb]

11 hours ago, FoxMike said:

Back in the fall, a thread was started about an MT Propellers.  Back then I had one on order for my Bravo.  I promised I would give a pirep when I got it installed.  I ordered the prop right after OSH and it arrived about Christmas.  I needed to help a friend in Titusville so I decided to stop in Deland and have them install and balance the prop.  Long story about install but I will save that for another day.  Since the install I have been to KTIX, M54 (Nashville) and back to Denver and done some local flying.  My impressions so far are

The prop (a four blade) is extremely smooth.  One reason I wanted to do this is that after 3.5 hours behind the Mc Cauley I needed to get on the ground for a spell.  The vibration was fatiguing and I often do long trips and I need 4-4.5 hour legs.  On the way home from Florida I did 4+ hour legs without difficulty.

The four blade MT is about 2" shorter than the McCauley.  It makes the cabin much quieter.  In fact I am very comfortable flying without a headset.  Since I like background music I still wear the headset a lot.

I found takeoff runs shorter and the climb rate better.  I also found I need to keep the taxi RPM down to 800 or lower or get going to fast.  

Landing is different, I think due to blade drag and the lighter prop.  The airplane seems to float less and decelerates faster which I rate as a positive factor.  I find I can hold the nose up longer as the tail has less weight to lift.  I have not put this to the ultimate test as yet.  The test will be a full load of fuel and two fat boys in the front seats.  The Bravo now handles much more like a K model.

The ride in turbulence is a little less desirable than it used to be.  With the heavy prop. the Bravo would really plow through the bumps.  It now bounces a bit more.

Cruise speed I am still working on.  I normally use 28/2300 and a fuel flow of 15.5. When the MT was set to that power I got the same indicated airspeed at lower altitudes (under 10K).  Since the prop is shorter I tried 29/2400 and found that the fuel flow was higher and the plane was a little faster and the gas mileage only decreased 3%.  I also tried 32/2200, fuel flow about 17.5gph.  The result was a good 5% higher indicated over the McCauley and the gas mileage was about the same or a little better.  The percent power however is 81%.  

When the weather gets warmer I will get an idea if the engine cooling is improved.  I think it might be.  

Well that is about as much as I have observed so far.  I see improvement in all the areas that I deemed important when I ordered the prop.  Not large improvements but certainly worthwhile improvements. The only potential problem is that to pour enough TKS fluid over the prop blades they increased the flow which seems to cheat the flow to the wings.  I only flew in a little ice so I need to evaluate this a little more.  One other thing I have found more difficult is trying to install the lower cowling.  A few more practice sessions may improve my skill at this.

 

5% higher or 3% higher indicated is nothing to sneeze at.

If you are indicting say 155 or 160?  That's 5-8 knots isn't it?

[FoxMike]

To give an answer about the improved  performance of the TLS with the MT propeller I would say all my flying and observations have been during below standard conditions.  Leaving Nashville on a really cold day I was getting 1400fpm on 32/2500 at nearly gross.  When things warm up a little it will be a better time to look at the numbers.  BTW MT says the performance for this propeller should be 8% shorter take off distance, 2% better climb, 2Kts better cruise and 10 pounds more useful.  I would wager that those figures are reasonably accurate.

[Txbyker]

I agree with the T/O performance.  I use Cloud Ahoy app to measure before and after T/O performance (Hartzel 3 versus MT 4) shows quite a bit shorter take off for the MT4.

Russ

[ArtVandelay]

What’s the weight of the MT propeller?

[LANCECASPER]

5 hours ago, FoxMike said:

To give an answer about the improved  performance of the TLS with the MT propeller I would say all my flying and observations have been during below standard conditions.  Leaving Nashville on a really cold day I was getting 1400fpm on 32/2500 at nearly gross.  When things warm up a little it will be a better time to look at the numbers.  BTW MT says the performance for this propeller should be 8% shorter take off distance, 2% better climb, 2Kts better cruise and 10 pounds more useful.  I would wager that those figures are reasonably accurate.

Can we ask how much it was installed?

[FoxMike]

Weight of the MT prop from my memory is 63lbs.

The cost is around $15K with nickel leading edge and hardware for TKS.  Install and balance were free if you go to Deland.

[carusoam]

Amazingly close to the price of the three blade TopProp...

Best regards,

-a-

[Seth]

That's a great looking prop on the Bravo.  Congrats!!  If my Missile prop ever has an issue and needs replacement I'll have to seriously consider the 4 blade MT for all the reasons noted AND the conversion from my full feathering prop (and danger of prop governor failure it holds on the Missile and Rocket).  The lighter weight on the nose would be huge for the Missile (as Erik's Rocket and now your Bravo demonstrate).

-Seth

[Guest]

Got to love the MT!

 

[aviatoreb]

16 minutes ago, M20Doc said:

Got to love the MT!

 

I'm curious - and not to ask why is your airplane hanging upsidown from the ceiling.

Why did you go 3 blades with that big 8 cylinder - why not 4 blades - or even 5?

[Guest]

23 minutes ago, aviatoreb said:

I'm curious - and not to ask why is your airplane hanging upsidown from the ceiling.

Why did you go 3 blades with that big 8 cylinder - why not 4 blades - or even 5?

Three blade MT on a Comanche imparts anti gravity properties.

The STC is held by Charlie Horton and is the only model available for the 400.

Clarence

[aviatoreb]

10 minutes ago, M20Doc said:

Three blade MT on a Comanche imparts anti gravity properties.

The STC is held by Charlie Horton and is the only model available for the 400.

Clarence

Anti-gravity is good for balloons.  But not speedy Comanche' 400reds.  

Oh.  I didn't realize there was an STC!  Mine is on a field approval and I figured yours was too - in which case I figured there was some leeway.  With 400hp I bet that baby could run a 5 blade if you wanted.

Anyone ever soup-up a Comanche' 400red to more than 400hp?  Like 500 or 600?  I mean heck if a 6 cylinder can go 350 in some versions why not 500 hp out of an over tweaked 8 cylinder?

 

[Guest]

11 minutes ago, aviatoreb said:

Anti-gravity is good for balloons.  But not speedy Comanche' 400reds.  

Oh.  I didn't realize there was an STC!  Mine is on a field approval and I figured yours was too - in which case I figured there was some leeway.  With 400hp I bet that baby could run a 5 blade if you wanted.

Anyone ever soup-up a Comanche' 400red to more than 400hp?  Like 500 or 600?  I mean heck if a 6 cylinder can go 350 in some versions why not 500 hp out of an over tweaked 8 cylinder?

 

They have been flown with a Garret TPE331.

[aviatoreb]

30 minutes ago, M20Doc said:

They have been flown with a Garret TPE331.

Sweet!

How many HP was that one?  So ...how fast did it go - and why didn't;t they produce it?!!

I bet it went a million.

[Guest]

Just now, aviatoreb said:

Sweet!

How many HP was that one?  So ...how fast did it go - and why didn't;t they produce it?!!

I bet it went a million.

I think there were two models use, 600-800hp.  I’ll see if I can find the story.

They also tried this:

[Guest]

6 minutes ago, aviatoreb said:

Sweet!

How many HP was that one?  So ...how fast did it go - and why didn't;t they produce it?!!

I bet it went a million.

Found it, page 39.

http://www.comancheflyers.com/publication/view/comanche-flyer-january-2016/

[MB65E]

FM! Your airplane looks gorgeous. Love the look!! I can't imagin taking the Lower cowl off with another stick in the way!! It was hard enough with the naca ducts and cam locks that pop out.

Thanks for the report! Hopfully the newer paint from MT and the nickel Leading edge last in the rain. Most MT's blast paint off when there is only mist in the air. 

-Matt

[slowflyin]

Anymore data?  Was hoping you could offer another PIREP. Thanks in advance.

[FoxMike]

Here is an update from a little over a 100Hrs of use.  After a few oil changes and an annual I have found a way to put the lower cowl on without too much hassle.  You have to put the front up in place before putting the rear in place.  It is definitely more difficult with the extra blade but doable.  In the hot summer weather the takeoff performance is better than with the 3 blade.  Initial climb is better but to get improved climb performance you need to climb at 80-85kts or so.  The oil temperature quickly rises so I have found that you have to push over and get the airspeed up to 110IAS or so.  The result is only a slight gain in climb rate.  

Overall I really like the prop.  The best like is the smoothness.  The second the ability to flare near stall and keep the nose wheel off the runway.  The third is the quieter ride.  I doubt the cruise is any better but to make MT happy I might report a one knot increase.  I used to set the power at 28/2300.  I have been using 29- 30/2200 with the 4 blade.   Passenger comments so far give high marks to the smoothness and lower racket level in the cabin.  The only problem so far is the tow bar.  I need to bend over a little farther so the bar will not bump one of the blades during turns.  This could be a problem when being tugged.  So far the tugs have had the tow ball mounted low enough that it has not been problem.  One other nit is taxi RPM needs to be kept around 700-800.  Not much of a problem as along the mags are in good shape and you have the engine leaned out.  

Well, That is about as much as comes to mind.  

Edited September 27, 2018 by FoxMike
Add another point and a picture

[FoxMike]

One more thing came to mind.  A  friend put an MT on his T Arrow about the same time I put mine on the Mooney.  He got the stainless leading edges.  Already the gravel is abrading the stainless, the nickel edges on mine are smooth as a babies butt.

 Leaf peeping this weekend and chasing down some $2.50 100LL at Rifle, Co.  Atlantic Aviation was the FBO.