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MT prop/shout out to McFarlane

Walt

Well Known Member
Ordered on Monday received this beauty on Friday, The service at McFarlane is superb!
Installed and balanced, looking at some test flight’s with it tomorrow.
MTV-9 replacing the Hartzell BA.

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Nice !!

Nice !!!
I have the same, can't compare as it's the only one I flew with.
I can say that it works flawlessly up to now. Only 40 hours done.


Looking forward to read your first impressions and any comments on the difference with the BA.
 
Flew about 4 hrs today with the new prop, a few observations:

Definitely smoother at all RPM ranges, can dial eng back as far as 2100 or less, which I would never do with the Hartzell and it was smooth the whole time. Did a 3 hr cross country and settled in with 2300 as a sweet spot compared to 2400 on the Hartzell. Do to low ceilings was never able to get above 4500ft.

Braking is insane, pull the power all the way back and the brakes are full on. Will need to adjust my "normal" landing profile, need to keep a little power in or she will start slowing quickly, great for steep approaches.

Idle RPM had to backed off a bit, it jumped up about 50 RPM.

Quick to spool up and shut down, the reduction in inertia is evident.

Not sure about cruise speed, although it seems pretty close to what I was seeing before. Need to get up to 8000-10,000 and see how it does.

With only a couple of take-offs to evaluate, but seems like improve climb, shorter ground roll.

Spinner fit perfect, exactly where my other one was, and all prebuilt, no drilling required!

About a 4-5lb weight loss off my nose which I am glad to have.

Quieter, noticeable improvement is sound level.

Overall, very very pleased.

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Fantastic

Hey Walt,

Thanks for the initial PIREP! My buddy Jim and I both have one......although the are currently flying in the shipping crate waiting for the airplane build to catch up with it :)

How far off was the balance initially and how close did you get the balance dialed in? Keep practicing that balancing because I intend on flying my airplane out there and have you do it haha.

I will be very interested in future about the performance and opinions on the MTV-9.

Thanks for posting!
 
Hey Walt,

How far off was the balance initially and how close did you get the balance dialed in? Keep practicing that balancing because I intend on flying my airplane out there and have you do it haha.

I will be very interested in future about the performance and opinions on the MTV-9.

Thanks for posting!

The Dynamic balance started at 0.310 which is on the high side, finished at 0.011 ips after 4 runs which is a very low level, better than average.
(my goal is 0.05 IPS after balance which is half the 'after balance' limit)

So despite people thinking their composite props feel smoother, which they generally do, they can still benefit significantly from a dynamic balance which every prop manufacturer recommends.

Red circle indicates upper limit of 0.2 IPS

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Performance testing

Good info on the performance tests and balancing. I can hardly wait to get the new prop on my plane:):)
 
Walt,

I have the same prop on my 6A, O360. Mine is super smooth except for when I throttle way back in cruise, say to 11in mp. Definitely get good braking, but also feel vibration at that setting. Do you feel the same?
 
Thanks Walt for the pirep.
Here's what I observed:

I do concur that I find acceleration and climb is stellar.
Again, no comparaison as it's the only prop I had on the 8.
All passengers comment on how smooth the engine is.

I do confirm that it brakes massively.
So much so that now, on downwind, I just increase the RPM to 2500ish and leave it there. In case of Go-Around, it's a short burst of 28 - 29 MP, quickly brought back to 25... It just zooms back in the air insanely...
Otherwise, it's too much braking...

I find that when heavy, or with a passenger, 2200 RPM and 75-80 KIAS on Base and Final gives +/- 400 Ft/min descend.
When solo and lighter, 2000/2100 RPM does the job until the numbers then flare and gradual power reduction.
I often or always land with some residual power... again, lot's of braking. Then idle when firmly on the runway.
I plan on having it balanced in the coming weeks.
 
Walt,

I have the same prop on my 6A, O360. Mine is super smooth except for when I throttle way back in cruise, say to 11in mp. Definitely get good braking, but also feel vibration at that setting. Do you feel the same?

We’ll, I avoid low mp setting at higher airspeeds, driving the prop/engine with airspeed can cause piston ring flutter and may‘detune’ a counter weighted crank.
 
I just ordered a MTV-20-B/183-50 electric prop for my IO-360, lead time is 9 months, order in May, won't get it until February. I'm surprised they had one in stock when lead time is so long.

Why did you go with the three blade over two? My understanding is that weight is only 1lb less with 2 blades, and cruise is very slightly better with 2, while acceleration is slightly better with 3.
 
I just ordered a MTV-20-B/183-50 electric prop for my IO-360, lead time is 9 months, order in May, won't get it until February. I'm surprised they had one in stock when lead time is so long.

Why did you go with the three blade over two? My understanding is that weight is only 1lb less with 2 blades, and cruise is very slightly better with 2, while acceleration is slightly better with 3.

The 3 blade is the only one that has been tested/certified on the high compression IO-370 engine.
Whirlwind, which I also looked at had the same advice 3 blade for the 370 was required.

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Copied Walt

As I tend to do, I copied Walt’s lastest upgrade. I flew out to 52F last week and installed the exact same prop on my plane (with Walt’s help of course).

I did a couple of local test flights then flew from Texas to Jacksonville, FL on Saturday. The prop runs very smoothly and overall there is less vibration. (Walt balanced both my old prop and the new one) There is a noticeable difference compared to the 2 blade Hartzell.

On the return trip I was at 7,000 ft where I was running full throttle 23.6 MP. I found that 2300 rpm was the sweet spot. My cruise speed was 159 kts which was maybe 1 less than the Hartzell.
 
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On the return trip I was at 7,000 ft where I was running full throttle 23.6 MP. I found that 2300 rpm was the sweet spot. My cruise speed was 159 kts which was maybe 1 less than the Hartzell.

159 knots? Is that with a O320? If it’s a 360, I would expect Full Throttle at 7000 to be 170+ knots..
 
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True air speed

159 knots? Is that with a O320? If it’s a 360, I would expect Full Throttle at 7000 to be 170+ knots..

Actually, it’s an IO 370 with high compression pistons. For what ever reason, this is about as fast as my plane has ever been. I have not done any testing to see if there is an air speed error. However, when my IFR check was done, air speed was correct using the test box (we only brought the air speed up to something less than 100 kts). Ground speed correlates well with TAS.

Going from my original O 360 to the IO 370 increased climb performance but it only added a few knots of top speed.
 
For those interested yesterday's flight at 7500' pretty well confirms no or negligible speed loss compared to what I was used to seeing on the Hartzell BA.
Note the RPM, would never cruise at that low an RPM with the BA, still smooth as glass and noticeably quieter!

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Cool

Very nice Walt....... I hear a lot about the MT smoothness and look forward to the experience in the near future.....keep posting your observations :)
 
Glad to hear it didn't significantly affect your cruise speed. While I have yet to try out my -8 at optimum cruise altitudes (7000 - 9000 MSL) with the 3-bladed MT, I really do like its climb performance as well as its smoothness and the aforementioned "airbrake option."

The only head-scratcher in my mind is MT's factory TBO recommendation(s), which seem largely based on time since manufacture rather than time in service.
 
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I see 72 months or 2400 hours TBO in the manufacturer's booklet.
That's for a MTV-9-B/183-50a
 
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