4 bladed propellers
- Thread starter Randy
- Start date
ground loop
Registered User
Anchorage
Has anyone been in touch with MT-propellars recently? I would love to hear the current status of a few of their products. The three gear composi-prop that is sort of a constant-speed prop without a governor really intrigued me.
bushmaster
GONE WEST
GLENBURN,ME
There is alot of prop tech out there but doesnt seem to get much interest from exp. or cert cub drivers or others in light aircraft only ultra lite users mostly but i see some are rated to like 750hp. the variable pitch versions sound good best of both worlds with out weight of constant speed or maint. Any thoughts
Dave Calkins
Registered User
Anchorage, Alaska
Maybe this talk of simple adjustable pitch props will spark some more discussion of the old "Aeromatic". Seems like the wood blades and lag bolt arrangement were the problem with that design, but I heard the performance range was actually quite good.
Anybody have a way to give a heads-up to our Euro SuperCub.org members to get some answers on the 4-blade thing??
Anybody have a way to give a heads-up to our Euro SuperCub.org members to get some answers on the 4-blade thing??
You know, I'm not so sure that most of the good performance credited to the AeroMatic isn't actually due to an entirely different prop. The Sensenich Sky Blade. Anybody got any personal experience with the Sky Blade? I know it was a two-position prop, but I've never laid my eyeballs on one. I've flown in a Pacer (PA-20, not a Tripacer with corrective surgery) with the AeroMatic, and I don't see why it deserves so much credit for being partcularly better than the right FP. A little better TO maybe, but sadly disappointing in cruise.
Dave Calkins
Registered User
Anchorage, Alaska
I sent a PM to "Swisscubpilot" in hopes that he'll get back to this thread with some '4-blade' answers.
Wingie, my knowledge of the Aeromatic is limited to a short discussion with a friend/past-employer of mine who had one on his stock PA-12 many years back. He said it helped alot for getting him out of the hole on skis, then provided a bit of cruise performance. Also, it is light. That's all I know.
What's with the "Sky Blade"? Is it a counterweight-actuated design?
Interesting stuff!
Wingie, my knowledge of the Aeromatic is limited to a short discussion with a friend/past-employer of mine who had one on his stock PA-12 many years back. He said it helped alot for getting him out of the hole on skis, then provided a bit of cruise performance. Also, it is light. That's all I know.
What's with the "Sky Blade"? Is it a counterweight-actuated design?
Interesting stuff!
Steve Pierce
BENEFACTOR
Graham, TX
Once the Aeromatic is set up it is impressive. I know a couple of Antiquer's who have them on everything from the PA16 to a Fairchild 24. They all tell me it is time cosuming to get the pitch for climb and cruise set just right but when it is done it will pull you out of a short strip and get you home faster.
Aeromatic Prop........
Gentlemen,
I flew behind a Aeromatic prop for several years, and the performance gain was just short of spectacular when compared to a fixed pitch prop.
I have often wondered why some entrepreneuer doesn't pick up the manufacturing rights, and make them again. With STC's, they would go like hot cakes. I have personally seen a experimental clipped wing cub that would cruise better than 100mph using a C-90 engine. Top speed was better than 115mph. This same craft would release itself from the bonds of earth with two aboard in 50 feet, and that was in the hot summer. I think Wag-Aero had the manufacturing rights some time ago, but sold them. Too bad the owner doesn't realize what he has. As far as being difficult to set up, it isn't. I never saw any problems with the lag bolts, or anything else for that matter, but if any problems did exist, a small amount of re-engineering would make this prop a very exciting performance investment.
Mike in NC
Gentlemen,
I flew behind a Aeromatic prop for several years, and the performance gain was just short of spectacular when compared to a fixed pitch prop.
I have often wondered why some entrepreneuer doesn't pick up the manufacturing rights, and make them again. With STC's, they would go like hot cakes. I have personally seen a experimental clipped wing cub that would cruise better than 100mph using a C-90 engine. Top speed was better than 115mph. This same craft would release itself from the bonds of earth with two aboard in 50 feet, and that was in the hot summer. I think Wag-Aero had the manufacturing rights some time ago, but sold them. Too bad the owner doesn't realize what he has. As far as being difficult to set up, it isn't. I never saw any problems with the lag bolts, or anything else for that matter, but if any problems did exist, a small amount of re-engineering would make this prop a very exciting performance investment.
Mike in NC
FlipFlop
Registered User
Maintaining at Flight Level Zero, requesting lower
Steve Pierce said:
Ditto those observations... I've heard lot's of positives (my Dad flew behind them for years), the only negative performance issue I've heard was that installed on an 85 hp Swift, if the engine coughed after the blades went to cruise (on takeoff), the airplane was too slow to go back to climb prop position... I'd love to have one, but I'm worried about the old wood and lag screws...
Steve Pierce
BENEFACTOR
Graham, TX
This is the man. http://www.aeromatic.com/
They aren't hard to set up just time consuming to get just the right pitch for clamb and cruise. I have seen a broken lag screw and read about an RV that shed a blade because they broke. I guess they can be exrayed.
They aren't hard to set up just time consuming to get just the right pitch for clamb and cruise. I have seen a broken lag screw and read about an RV that shed a blade because they broke. I guess they can be exrayed.
Now, I admit that I'm not first-hand experienced much with the AeroMatic (Koppers) prop, having only ridden behind one on a Short Wing. I also got some right seat time in a Swift a few years ago, but was less than inspired with the reputation claimed (at that time) that the AeroMatic shed blades regularly. I'm also not positive that the Sensenich I refered to earlier was really called a Sky Blade, as that may have been a mistake passed on to me by one of the Old Timers. But in defense of my remark, and because no one has addressed my question, I'd like to point out the two-position wooden bladed prop that Piper included on the TC for the PA-20 (see Item 1{d} & 2({e}& 3{d}) and the PA-22 (Item 4). Look also at the PA-18 TCDS, which also lists Item 3(c) for an O-290-D powered airplane, but the asterisk indicates "someone else" had it approved. Possibly Sensenich? These were not really all that scarce, from what a lot of really Old Timers tell me, but were "killed" by the AD (63-19-04) to remove the blades very often. This AD mentions torqueing the lag (blade retaining) bolts on reassembly. This could account for the possible confusion that "all of these props" were Koppers (AeroMatic). The Old Guys tell me that the real performer wasn't the Koppers, it was the Sensenich. Just wondering, still, if any one has ever flown behind one of these. I guess I don't want to find one, but I still wonder if the AeroMatic was the good one, or maybe not?
BES
Registered User
Esbjerg, Denmark
Well, I guess I'll be the first European member to try answering your questions on 4-blade props. We seem to use quite a few retired Pawnees for towing gliders, over here. Most of these Pawnees and some Super Cubs have been reequipped with MT or (mostly) Hoffmann propellers . These are wooden propellers with a GRP overlay. Experience has shown that the 4 blade props are hard wearing, make (a lot) less noise, have better ground clearence and are lighter than aluminum 2-blade props.
Provided you can live with the weird looks, they are great performers.
Aeromatics, on the other hand, we have had a lot of trouble with. The Danish Army once used spotter planes with Continental O-300 engines and Aeromatic props. Due to the great summer/winter variation in humidity in this country, the blades tended to shrink sufficiently in winter to leave the hubs. The Aeromatics wound up grounded after a while. They have one such spotter plane in our vintage aircraft museum. While they have an Aeromatic prop for it, they fly it with a fixed prop for fear of the Aeromatic shedding a blade in flight.
Best
Bent
Provided you can live with the weird looks, they are great performers.
Aeromatics, on the other hand, we have had a lot of trouble with. The Danish Army once used spotter planes with Continental O-300 engines and Aeromatic props. Due to the great summer/winter variation in humidity in this country, the blades tended to shrink sufficiently in winter to leave the hubs. The Aeromatics wound up grounded after a while. They have one such spotter plane in our vintage aircraft museum. While they have an Aeromatic prop for it, they fly it with a fixed prop for fear of the Aeromatic shedding a blade in flight.
Best
Bent
funseventy
Registered User
Priest River, Idaho
We picked up an experimental 180hp Super Cub with a Cub Crafter wood prop. It was incredibly light but the performance wasn't there. I believe the main reasons for trying to develop a wood prop were: 1) The lead time for metal props and 2) The Cost of the metal props. The cost for the Pawnee prop 84/42 was $3900, but in comparison worth the cost.
IMHO
IMHO
