Floatplaneguy
New Member
What’s better? 2004 A1b on Wipline Amphibs. Mt thinks 83”. I Like lighter faster Ultra. Thoughts?
Husky MT Ultra Vs 83” Expedition
- Thread starter Floatplaneguy
- Start date
harry harper
Active Member
Curious about your rationale re your comment CB. MT static trust pull data shows the 210cm (83") 2blade MT to have 16# more pull than the 205CM. What could be bad about that? And re floatplanes and noise foot print. Can't imagine any increase noise from a 210CM MT @2700 would hold a candle to the average IO520 Continental powered floatplane swinging an 86 or 88" Mac turning 2850 rpm.
Harry,
In 1998-1999 one of my Airshow sponsors was MT propeller. In exchange for free props I did extensive flight tests on 6 different propeller blade designs for MT compiling pages of data at different altitudes and power settings. MT had static thrust #’s on each design but it was worthless as a predictor of in flight performance because a propeller on an aircraft is only in that condition for the first couple seconds after brake release on takeoff ground roll. As soon as a plane hits about 15 mph it’s biting into undisturbed air and efficiency skyrockets. In a static thrust test the prop is churning in its own vortex of turbulent air, similar to a boat propeller that is cavitating while tied to a dock. Helicopters will support far more weight when they hit 15 mph and the rotor is biting into undisturbed air than they will when hovering in their own rotor-wash.
The props with the best static thrust were often the worst in flight performance. Nobody would try to evaluate a boat propeller’s thrust while it was cavitating at a high power setting while anchored still in the water. Evaluating a propeller while cavitating in its own prop wash is an easy test to conduct but it demonstrates little of any value. Props can only be evaluated in flight where a couple factors stood out. First, 2 blade props normally out perform 3 (or 4) blade designs. More blades are required if prop clearance is a problem. Second, thinner blades (usually but not always metal) have a better thrust to drag ratio and are faster in flight than thicker wood or composite blades.
Finally, and I hesitate to even say this here because I’m going to get grief for it, the propeller with the least amount of static thrust on a 180hp Husky is the standard metal 76” Hartzell prop. But in flight, according to Aviat’s test pilot who has flown and evaluated just about every prop you can bolt to that O-360, the propeller that produces the highest top speed is that 76” metal Hartzell. My own tests of several MT props on my Glasair III produced the same result. Nothing MT came up with in 6 tries was able to come within 10 mph of the thin 2 blade metal Hartzell in top speed.
Perhaps greater static thrust will get a float plane up on the step quicker and that’s a positive and a lighter composite blade might be smoother so there are other factors than top speed. But less prop clearance is a negative and that combined with the added drag of an 83” prop would make me shy away from it. All the best.
Chip
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Floatplaneguy
New Member
Larson
Active Member
I’ve had standard 76” and 2 blade MT (210cm). A1, Wip 2100A’s
MT out performs 76” all day. Pulls it out of the water and into climb way better than 76”
Stainless leading edge allows for excellent water abrasion resistance.
lighter weight helps with Wip weight and balance. You will need weight in the baggage area to be inside forward C of G.
MT out performs 76” all day. Pulls it out of the water and into climb way better than 76”
Stainless leading edge allows for excellent water abrasion resistance.
lighter weight helps with Wip weight and balance. You will need weight in the baggage area to be inside forward C of G.
tbienz
Well-Known Member
I went from a metal 76 to an MT 210cm prop a rather shortly after buying the Husky (‘94 A-1). Not sure about top speed (which is nice, but at the end of the day, all Husky aircraft are slow do I don’t care that much) but takeoff distance, descent rate at idle and especially climb performance when high and hot in the mountains was so much better that it felt like a completely different plane. I would never go back even if the metal prop has a higher top end. I hope my old 210cm continues to last because I love it. Zero maintenance in about 8 years. If I want to fly fast, I’ll take a different plane. The only complaint I’ve heard from others when lots of Huskys are flown together at the Root, is that my plane is a little loud at 2700 compared to planes with other props. But my other plane is an MU-2. so comments about engine noise are familiar to me 
Floatplaneguy
New Member
I Ordered the Ultra. Keep you posted once it’s installed next week.
Ak Kurt
Well-Known Member
Arnie Loera
New Member
A question for the MT Ultra users. I put a MT Ultra on my 1989 A1 on Bauman Floats. and have had issues with prop surging. Much improved with rebuilt Hartzell governor but still has a surge around 25 squared. Plane absolutely hops off the water! I have a 1990 A1 on 31 tundra and skis in the winter. No issues and had refurbished last year.been very happy with it? Live/fly out of beautiful Dillingham Alaska. Any advice appreciated. Arnie Loera
Arnie Loera
New Member
Oops should say have had a 3 blade MT for years with stock Hartzell Governor with no issues at all?
I had that 25 rpm slight surging issue too, but installing the MT governor solved the issue. Think it has about a third more oil pressure than the Hartzell gov.
And remember, floatplanes like a longer prop, most efficient is a 2 blade turning slower. The MT Ultra likes to run slower rpm's than the Hartzell Trailblazer without losing much airspeed. Trailblazer seems to lose more speed once below about 2350rpm compared to the Ultra which runs at 2200 range with about the same airspeed, and say 24" MP. Hard to tell much difference otherwise, but cannot get Trailblazer to be as economical on fuel as the Ultra, it just likes the reduced rpm without as much speed loss compared to the Trailblazer.
Have tried it on both Husky and hot rod 175, same results.
The Ultra runs a bit smoother so any slight issue is more evident with the Ultra vs Trailblazer.
Plus MT gov weighs a couple lbs less than Hartzell gov.
John
And remember, floatplanes like a longer prop, most efficient is a 2 blade turning slower. The MT Ultra likes to run slower rpm's than the Hartzell Trailblazer without losing much airspeed. Trailblazer seems to lose more speed once below about 2350rpm compared to the Ultra which runs at 2200 range with about the same airspeed, and say 24" MP. Hard to tell much difference otherwise, but cannot get Trailblazer to be as economical on fuel as the Ultra, it just likes the reduced rpm without as much speed loss compared to the Trailblazer.
Have tried it on both Husky and hot rod 175, same results.
The Ultra runs a bit smoother so any slight issue is more evident with the Ultra vs Trailblazer.
Plus MT gov weighs a couple lbs less than Hartzell gov.
John
Arnie Loera
New Member
Thanks for the advice. Did the MT governor come ready to bolt on or did you have to modify to fit? Where did you purchase it?
Arnie
Arnie
MT advised to buy through Van's Aircraft, they have them in stock. Bolt on certified.
Flying Dave
Active Member
Add us to the Ultra crowd. Ordered one from John during OSH after looking at them for two years. Will be keeping my eyes peeled for the big brown truck!
Bowie
New Member
Was the 3 blade MT on your float plane? If so does the Ultra noticeably outperform it in terms of time off the water and climb rate? I have a 3 blade MT (198cm) on my A1B-200. I’m considering the two blade MT to lighten the nose and I’m curious about any performance gains.
Flying Dave
Active Member
Installed! Now gotta find some time to fly it.
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