Fastest planes on the least amount of HP

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Pops

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It could be a fun little plane, but for a 2 place, the published 436 lb useful load will hurt it in the marketplace. Two people with clothes, headsets, maybe a toothbrush for an overnight trip, and there's not much weight left for fuel to feed that 100 HP Rotax.
The present MTOW is given as 1058 lb, so plenty of room below the present LSA max weight. If they can find a safe way to carry 50-75 lbs more, it could be a more practical (and popular) plane.

Next, find a way to power it with something less dear than a Rotax 912ULS and sell a lot more of them. The RV-12 (912ULS stock powerplant) has been successfully powered by a Suzuki (Aeromomentum) AM15, so there's that.

I like what Bob Barrows did on designing the Bearhawk LSA. Build it LSA or make the GW at 1500 lbs per his max designed GW.

On the JMR, I designed it for ultimate of 10.1 g's , for a rating of 6,3 g's at a GW of 1100 lbs. So there is room for a little increase in GW. Don't know where you would put the increase is weight. As designed , you can have full fuel and pilot of 300 lbs and no baggage , or baggage weight that reduces the pilot weight the same amount with a max baggage weight of 50bs. All well within the CG envelope.
 

Hephaestus

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It could be a fun little plane, but for a 2 place, the published 436 lb useful load will hurt it in the marketplace. Two people with clothes, headsets, maybe a toothbrush for an overnight trip, and there's not much weight left for fuel to feed that 100 HP Rotax.
The present MTOW is given as 1058 lb, so plenty of room below the present LSA max weight. If they can find a safe way to carry 50-75 lbs more, it could be a more practical (and popular) plane.

Next, find a way to power it with something less dear than a Rotax 912ULS and sell a lot more of them. The RV-12 (912ULS stock powerplant) has been successfully powered by a Suzuki (Aeromomentum) AM15, so there's that.
As a sasquatch pilot's fast single... ;) I can work with it as - is. But the 912 isn't on my preferred choice list, but we know there's a group of options that also fit for size/weight.

TL Stream also appears to be a derivative of the Asso X. Now if only the Prime or Stream were a reasonable price - both are in that 200k Euro+ range. Apparently the blackshape has a taller fuse for taller pilots?

Hopefully Fisher considers a similar tweak since north americans tend to be a touch taller.
 

cluttonfred

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In the North American market, I would say that 450 lb is about the right number for a two-seater in terms of acceptable minimum *payload* with full fuel and 500 is better for a cross-country tourer. 400 lb is probably acceptable for a fun machine without serious cross-country travel in mind, but even then 450 would be better. Per the CDC using 2015-2018 numbers, the average American man weighs about 200 lb (91 kg) and stands 5' 9" (175 cm) tall and the average American woman is 171 lb (78 kg) and 5' 3-1/2" (161 cm) tall. Obviously, you need to go higher if you want to include at least 90% of the population. I tend to use 200 kg (440 lb) for people and 50 kg (110 lb) for baggage in my calculations knowing that airplanes, like people, tend to gain weight with time so it's better to start out with a little cushion in the numbers.
 

edwisch

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A good candidate for speed/power is the pre-war German Möller Stomo. 94 MPH on 18 HP. The early Mooney Mites had, IIRC, 26 HP.
 

llemon

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As a sasquatch pilot's fast single... ;) I can work with it as - is. But the 912 isn't on my preferred choice list, but we know there's a group of options that also fit for size/weight.

TL Stream also appears to be a derivative of the Asso X. Now if only the Prime or Stream were a reasonable price - both are in that 200k Euro+ range. Apparently the blackshape has a taller fuse for taller pilots?

Hopefully Fisher considers a similar tweak since north americans tend to be a touch taller.

There are at least 2 Asso clones in production; Blackshape and Terragon. The TL looks like its a third.

The UL Shark is quite similar but a unique design, and maybe worth looking at for someone who doesn't want a Asso type.
 

sotaro

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To be clear, Strojnik wrote that the engine was turning 5000 rpm direct drive, and he thought the prop was 50% efficient. The Kawasaki engine was used for the record attempt, with the prop from the motor glider S-2. The upshot is about 15 hp delivered as thrust. The Rutan Quickie, at 126 mph with 18hp to the prop is still probably less than the S-4 Laminar Magic. How could that be?
 

rotax618

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The Q1 Quickie used a 44” dia prop on the Onan, it cruised at 3000-3400 rpm, the fourstroke was probably producing a fair amount of power at those revs. The largest prop that a direct drive Kawasaki could swing would be about 40”, without being horribly inefficient, you wouldn’t get much thrust from that setup, twostrokes have a very steep power curve.
 

BBerson

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Mark Stull liked 48” diameter and less rpm. Direct Drive ( post 35):
“I decided to try an even larger diameter prop, learning from my previous experiments, a 48" by 22" Tennessee wood prop. I'm getting even more thrust, a deeper, better, quieter sound, and better fuel economy.”
 
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Victor Bravo

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The Luciole should be mentioned here, I believe it does 110-120 MPH on 25HP (wikipedia) using a reliable "everyday" 4-stroke engine. That's over 4MPH/HP and has an economy cruise "consuming only 4.5 litres/hour at 150 km/h (93 mph)" (wikipedia). That's 77.5 miles per gallon. it is also a usable sportplane (instead of a one-off racer or dedicated record airplane). It doesn't have any flight characteristics that would prevent an average pilot from operating it as a sportplane. That's about as good as you're going to do where you can build it yourself, and achieve that kind of performance without a university or an aerospace company behind you IMHO.

Colomban's MCR-100 Ban-Bi does over 2MPH/HP (80 HP, 170 MPH cruise, 190 MPH max, from Wikipedia). The brochure says it's capable of 59 miles per gallon at 130 MPH, using the Rotax 4-stroke, Vmc is 53 MPH, and the takeoff run is 420 feet... but Colomban's airplanes do have a history of meeting the brochure performance. It does all this with two modest size people and an overnight bag, and a decent climb rate, easy tricycle ground handling, and it's something totally usable and pleasant as an everyday sportplane; that's a really high bar to set.

The last version of Monnett's "Mini-Moni" (clip wing) did 130-140 MPH on a 30HP engine, which is good, but the engine was one of the more problematic 2-strokes... probably made one hell of a racket too. He apparently shelved it because it wasn't anything he wanted an average pilot to be flying on that tiny little wing anyway.
 
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Sraight'nlevel

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The Luciole should be mentioned here, I believe it does 110-120 MPH on 25HP (wikipedia) using a reliable "everyday" 4-stroke engine. That's over 4MPH/HP and has an economy cruise "consuming only 4.5 litres/hour at 150 km/h (93 mph)" (wikipedia). That's 77.5 miles per gallon. it is also a usable sportplane (instead of a one-off racer or dedicated record airplane). It doesn't have any flight characteristics that would prevent an average pilot from operating it as a sportplane. That's about as good as you're going to do where you can build it yourself, and achieve that kind of performance without a university or an aerospace company behind you IMHO.

Colomban's MCR-100 Ban-Bi does over 2MPH/HP (80 HP, 170 MPH cruise, 190 MPH max, from Wikipedia). The brochure says it's capable of 59 miles per gallon at 130 MPH, using the Rotax 4-stroke, Vmc is 53 MPH, and the takeoff run is 420 feet... but Colomban's airplanes do have a history of meeting the brochure performance. It does all this with two modest size people and an overnight bag, and a decent climb rate, easy tricycle ground handling, and it's something totally usable and pleasant as an everyday sportplane; that's a really high bar to set.

The last version of Monnett's "Mini-Moni" (clip wing) did 130-140 MPH on a 30HP engine, which is good, but the engine was one of the more problematic 2-strokes... probably made one hell of a racket too. He apparently shelved it because it wasn't anything he wanted an average pilot to be flying on that tiny little wing anyway.
Briggs Stratton Vanguard delivers only 18 hp on brochure.
 

TiPi

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Briggs Stratton Vanguard delivers only 18 hp on brochure.
That's the 35, the Luciole uses the 38, rated at 23hp. Remove the fan, tidy-up the intake & valve seats and it will deliver 25hp.
I have been in contact with a UK company that uses 2 of the 38s, in EFI. They managed to get 27hp at 3,600rpm with some light work in the intake/valve area. The limit on their EFI engines is the fuel system, the fuel delivery max's out at around 27hp.
 

TiPi

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The Luciole should be mentioned here, I believe it does 110-120 MPH on 25HP (wikipedia) using a reliable "everyday" 4-stroke engine. That's over 4MPH/HP and has an economy cruise "consuming only 4.5 litres/hour at 150 km/h (93 mph)" (wikipedia). That's 77.5 miles per gallon. it is also a usable sportplane (instead of a one-off racer or dedicated record airplane). It doesn't have any flight characteristics that would prevent an average pilot from operating it as a sportplane. That's about as good as you're going to do where you can build it yourself, and achieve that kind of performance without a university or an aerospace company behind you IMHO.

Colomban's MCR-100 Ban-Bi does over 2MPH/HP (80 HP, 170 MPH cruise, 190 MPH max, from Wikipedia). The brochure says it's capable of 59 miles per gallon at 130 MPH, using the Rotax 4-stroke, Vmc is 53 MPH, and the takeoff run is 420 feet... but Colomban's airplanes do have a history of meeting the brochure performance. It does all this with two modest size people and an overnight bag, and a decent climb rate, easy tricycle ground handling, and it's something totally usable and pleasant as an everyday sportplane; that's a really high bar to set.

The last version of Monnett's "Mini-Moni" (clip wing) did 130-140 MPH on a 30HP engine, which is good, but the engine was one of the more problematic 2-strokes... probably made one hell of a racket too. He apparently shelved it because it wasn't anything he wanted an average pilot to be flying on that tiny little wing anyway.
The Luciole is very restricted in pilot weight, about 80kg (MTOW is 200kg, empty ~100kg and then you need some fuel as well).

Other planes in that class are the SD-1 Minisport and the Pik-26. The Pik-26 could benefit from a lighter engine, the often used 2CV engine is quite heavy. Even some of the Janowski models should make this list.
 

Pilot-34

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My 360 powered Long EZ burns 5.4 GPH @ 200 MPH (economy cruise) so.... 37 MPG. Now, that's at between 16-18 K feet leaned to 40 degrees LOP. Also, that's with dual Light Speed Engineering electronic ignitions (worth about 15% less fuel burn than mags), 10-1 compression, porting, etc. and an Ellison throttle body. And a very slicked up airframe. In my racing days I found out in testing that waxing the entire airframe was worth 5 MPH (that's a lot) for top speed. I think the Cafe Foundation got the exact same results with a Mooney. The details (as I remember) was that they washed the plane then did a top speed test and landed. A dozen or so guys waxed the plane in 15 minutes then did the retest. BTW, those Formula One 200 CI Reno racers kick out around 150 HP at 4,500 - 5,000 RPM and only last for about 10 minutes.
Good lord if a wax was worth 5 mph what was a good wash worth ?
 

Battler Britton

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The Luciole should be mentioned here, I believe it does 110-120 MPH on 25HP (wikipedia) using a reliable "everyday" 4-stroke engine. That's over 4MPH/HP and has an economy cruise "consuming only 4.5 litres/hour at 150 km/h (93 mph)" (wikipedia). That's 77.5 miles per gallon. it is also a usable sportplane (instead of a one-off racer or dedicated record airplane). It doesn't have any flight characteristics that would prevent an average pilot from operating it as a sportplane. That's about as good as you're going to do where you can build it yourself, and achieve that kind of performance without a university or an aerospace company behind you IMHO.

Colomban's MCR-100 Ban-Bi does over 2MPH/HP (80 HP, 170 MPH cruise, 190 MPH max, from Wikipedia). The brochure says it's capable of 59 miles per gallon at 130 MPH, using the Rotax 4-stroke, Vmc is 53 MPH, and the takeoff run is 420 feet... but Colomban's airplanes do have a history of meeting the brochure performance. It does all this with two modest size people and an overnight bag, and a decent climb rate, easy tricycle ground handling, and it's something totally usable and pleasant as an everyday sportplane; that's a really high bar to set.

The last version of Monnett's "Mini-Moni" (clip wing) did 130-140 MPH on a 30HP engine, which is good, but the engine was one of the more problematic 2-strokes... probably made one hell of a racket too. He apparently shelved it because it wasn't anything he wanted an average pilot to be flying on that tiny little wing anyway.

Perfect...

You could also talk about an other Michel Colomban design... Cricri MC15 137 Mph on max 30 hp

183 Mph on JetCat engines

don't forget also, the Serge Pennec Gaz'aile 2 whith more than 140 Mph on the smalest engine of the range
around 50 hp ( 136 Mph @75% ...41 hp)
 
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