What can 100hp do? LSA report

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Dave Taylor
I have a friend who just bought one of these
http://www.czaw.cz/files_plane1/pictures/fly_by_back.jpg

100hp 4cyl 4cycle air/'water' cooled engine.

He reports it did 120kts ave gs on 6gph, he took it to 14.5K, it takes off in 400', he can putter around the local area at 3gph, endurance 6 hours.

Even if you can't stand the things, even if you only see all its faults, you have to admit it is pretty darned capable!

I have not yet mentioned the terrific view out the canopy, the very modern interior, the two glass panels and complete lack of round dials. Makes everything I have ever flown look shabby!
 
If I only had a spare $120k hanging around. I could save about $5/hour on fuel. Sigh, there's no free lunch. Nice plane, I've been interested in the Mermaid for a while, but it's been on the back burner I guess.
 
I have a friend who just bought one of these
http://www.czaw.cz/files_plane1/pictures/fly_by_back.jpg

100hp 4cyl 4cycle air/'water' cooled engine.

He reports it did 120kts ave gs on 6gph, he took it to 14.5K, it takes off in 400', he can putter around the local area at 3gph, endurance 6 hours.

Even if you can't stand the things, even if you only see all its faults, you have to admit it is pretty darned capable!

I have not yet mentioned the terrific view out the canopy, the very modern interior, the two glass panels and complete lack of round dials. Makes everything I have ever flown look shabby!

I paid $5,000 for my Cougar C-85. It will do 150 mph on about the same. Nice glass panel and GPS. I completely rebuilt it (Airframe) so it looks brand new. Most of the parts are new. I am working on a single rotor mazda engine for it that will put it in the 125 hp class turbo and I will be traveling warp speed at altitude. Cost so far around $7,000.00

Maybe there is a free lunch you just have to look harder for it.

Dan
 

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Even if you can't stand the things, even if you only see all its faults, you have to admit it is pretty darned capable!
The SportCruiser is a nice airplane. It wasn't on my list, because it didn't meet my requirement for an IFR-capable aircraft, but for someone who wants a pure VFR cruiser, it's worth looking at.
 
I have a friend who just bought one of these
http://www.czaw.cz/files_plane1/pictures/fly_by_back.jpg

100hp 4cyl 4cycle air/'water' cooled engine.

He reports it did 120kts ave gs on 6gph, he took it to 14.5K, it takes off in 400', he can putter around the local area at 3gph, endurance 6 hours.

Must be a Rotax 912 or 914 in it. An honest 100 hp. The Continental O-200 we used to have in Cessna 150s seemed pretty anemic, and when I flew a '67 Aircoupe with its C-90 (90 hp) it outran the 150s every which way, including shorter takeoff, better climb and much faster cruise. The C-90 generates its horses at a considerably lower redline RPM that does the O-200, so less power is lost to prop drag. The Rotaxes are similarly more efficient. The small Continentals also usually need valve work around midway to TBO.
A 150 would never get to 14.5K, I don't think. There were warm days here when they would hardly reach 5K at gross. I think most LSAs will outperform some of the old lightplanes, especially those using the slick and light composites and engines other than the O-200.

Dan
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Must be a Rotax 912 or 914 in it. An honest 100 hp. The Continental O-200 we used to have in Cessna 150s seemed pretty anemic
The O-200 makes an honest 100 HP, just like the Rotax 912ULS. (A Rotax 914 disqualifies the aircraft for LSA: must be normally aspirated.) My Zodiac has an O-200A in it, just like a 150, but makes 172-class performance numbers with it.

The 150's performance is due to the 150's draggy airframe, not the engine.

Most non-tube-and-fabric LSAs use the Rotax 912ULS instead of the O-200A for two reasons: it's 60 pounds lighter (though the required cooling system takes away some of that advantage) and it's $8000 cheaper.
 
A 150 would never get to 14.5K, I don't think. There were warm days here when they would hardly reach 5K at gross. I think most LSAs will outperform some of the old lightplanes, especially those using the slick and light composites and engines other than the O-200.

Dan

Never had trouble getting up to 10K in a Cessna 120 with a mighty Continental 85...
 
Jay, while your shiny new O-200 was almost certainly producing 100HP when it graced the friendly skies of South Arkansas, I'd be willing to bet the average O-200 in the average C-150 isn't producing near that much power.

The O-200 makes an honest 100 HP, just like the Rotax 912ULS. (A Rotax 914 disqualifies the aircraft for LSA: must be normally aspirated.) My Zodiac has an O-200A in it, just like a 150, but makes 172-class performance numbers with it.

The 150's performance is due to the 150's draggy airframe, not the engine.

Most non-tube-and-fabric LSAs use the Rotax 912ULS instead of the O-200A for two reasons: it's 60 pounds lighter (though the required cooling system takes away some of that advantage) and it's $8000 cheaper.
 
Jay, while your shiny new O-200 was almost certainly producing 100HP when it graced the friendly skies of South Arkansas, I'd be willing to bet the average O-200 in the average C-150 isn't producing near that much power.
Hm. Good point. You won't find many 150s with factory new O-200s on them. OTOH, does anyone know what a 6000-hour Rotax 912ULS does?
 
Isn't the gross weight of each about the same, 1600lbs?
C150 vs Sportcruiser
 
Jay, while your shiny new O-200 was almost certainly producing 100HP when it graced the friendly skies of South Arkansas, I'd be willing to bet the average O-200 in the average C-150 isn't producing near that much power.

Even after installing a freshly overhauled O-200 in our 150s, the performance would be no better that with the old one. I still think the O-200 is lacking something, even though I know the 150 airframe is a barn door.
Some guy a few years ago stuck a 100 hp Subaru on a 150 and got some good increases in performance out of it, better than Cessna's numbers. I don't have the article anymore and I wish I had the new numbers. Either the Soob was producing more than 100 hp or the O-200 was a joke. That's not to say I'm a Soob fan; I'm not, not after installing a 130-hp Soob in a Glastar and flying it. Shoulda stuck with the Lyc 125 and made a much better airplane of it. A Lyc can be run at any cruising RPM up to redline, giving good cruise numbers, whereas the Soob's 5600 RPM is OK for very short periods but it'll wear out quickly at that speed and consumes enormous amounts of fuel, so you end up cruising at around 4600 and giving up a lot of cruise speed.

Dan
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Even after installing a freshly overhauled O-200 in our 150s, the performance would be no better that with the old one. I still think the O-200 is lacking something, even though I know the 150 airframe is a barn door.
Some guy a few years ago stuck a 100 hp Subaru on a 150 and got some good increases in performance out of it, better than Cessna's numbers. I don't have the article anymore and I wish I had the new numbers. Either the Soob was producing more than 100 hp or the O-200 was a joke. That's not to say I'm a Soob fan; I'm not, not after installing a 130-hp Soob in a Glastar and flying it. Shoulda stuck with the Lyc 125 and made a much better airplane of it. A Lyc can be run at any cruising RPM up to redline, giving good cruise numbers, whereas the Soob's 5600 RPM is OK for very short periods but it'll wear out quickly at that speed and consumes enormous amounts of fuel, so you end up cruising at around 4600 and giving up a lot of cruise speed.

Dan

Rotax 912 s have been fitted in on C-152 airframes in Europe for a while now. It definitely increases the performance and gets another 40 or so pounds of useful load out of the deal.
 
William Wynne, the Corvair conversion guy, put an O-200 on his dyno and did some tests. The results are here. http://www.flycorvair.com/thrust.html

Yes he is selling a conversion plan for an engine that competes with the O-200 but it has some very interesting and not really surprising results.
 
William Wynne, the Corvair conversion guy, put an O-200 on his dyno and did some tests. The results are here. http://www.flycorvair.com/thrust.html

Yes he is selling a conversion plan for an engine that competes with the O-200 but it has some very interesting and not really surprising results.
Hm. That says the 601XL will meet LSA specs on 80 HP at the prop...

You're right, that is an interesting result. Do you intend to have yours meet LSA standards (even though you're certifying it as E-AB)?

I also wonder just what effect using an old, but fairly recently overhauled, engine has as opposed ot using a factory new one. Probably not much, but is it quantifiable?

I guess I'm not surprosed that Continental used grpss HP, not net. As long as everyone used the same meaning for "horsepower", it didn't matter much. I suspect that Rotax and Jabiru are using net HP, though, and while I think that's ultimately more honest, it also means that direct comparisons can be misleading.
 
William Wynne, the Corvair conversion guy, put an O-200 on his dyno and did some tests. The results are here. http://www.flycorvair.com/thrust.html

Yes he is selling a conversion plan for an engine that competes with the O-200 but it has some very interesting and not really surprising results.

See, I told you so :)

From this page http://www.flycorvair.com/thrustjune.html
The thrust reading for the C-85 (85 hp) was 340 lbs, while the O-200 (100 hp, ha!) was 335. Five pounds less. Now, the Cessna 120 would have a slightly lower cruise speed than the 150, so the prop would have a little less pitch and would be expected to produce a little more static thrust than a C-85 with a coarser prop, but for the O-200 to actually put out less thrust than the C-85 is telling. And that's the reason the old Aircoupe with its C-90 flew so much better than the 150s we had. The O-200 is a pretender.

Dan
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I paid $5,000 for my Cougar C-85. It will do 150 mph on about the same. Nice glass panel and GPS. I completely rebuilt it (Airframe) so it looks brand new. Most of the parts are new. I am working on a single rotor mazda engine for it that will put it in the 125 hp class turbo and I will be traveling warp speed at altitude. Cost so far around $7,000.00

Maybe there is a free lunch you just have to look harder for it.

Dan


No...there is not free lunch. That is unless you place no value on your time.

I work 50-60 hours weeks and have a busy weekend schedule. I have NO TIME to play backyard aircraft manufacturer. Even if I did, all the time building and not flying....that would be pure misery.

So while I applaud your skills at building, and am truly happy for you, it is not the answer for everyone.

Why is it that builders seem to think that theirs is the "best" way and all someone has to do is open their eyes and see that?
 
Why is it that builders seem to think that theirs is the "best" way and all someone has to do is open their eyes and see that?
I don't know, but I get that a lot. "Why would anyone spend $133K for an airplane I can build for $60K with that avionics package?" Perhaps it's because I don't have the time to sink into building an airplane, and wasn't paticularly interested in waiting several years to go flying...
 
Yes the maximum speed in level flight with maximum continuous power (Vh) of my 601XL will be =<120 Knots. Keep in mind though, I the builder gets to say what "maximum continuous power" is.

Hm. That says the 601XL will meet LSA specs on 80 HP at the prop...

You're right, that is an interesting result. Do you intend to have yours meet LSA standards (even though you're certifying it as E-AB)?

I also wonder just what effect using an old, but fairly recently overhauled, engine has as opposed ot using a factory new one. Probably not much, but is it quantifiable?

I guess I'm not surprosed that Continental used grpss HP, not net. As long as everyone used the same meaning for "horsepower", it didn't matter much. I suspect that Rotax and Jabiru are using net HP, though, and while I think that's ultimately more honest, it also means that direct comparisons can be misleading.
 
See, I told you so :)

From this page http://www.flycorvair.com/thrustjune.html
The thrust reading for the C-85 (85 hp) was 340 lbs, while the O-200 (100 hp, ha!) was 335. Five pounds less. Now, the Cessna 120 would have a slightly lower cruise speed than the 150, so the prop would have a little less pitch and would be expected to produce a little more static thrust than a C-85 with a coarser prop, but for the O-200 to actually put out less thrust than the C-85 is telling. And that's the reason the old Aircoupe with its C-90 flew so much better than the 150s we had. The O-200 is a pretender.

Dan

"Telling"? What it's telling us is that static thrust is a pointless test. The C85 has a red line of 2575 RPM and was running at 2350 rpm (data per above web site) The O-200 has a red line of 2750 and was running at 2332 - higher red line but lower RPM during the test. So the C-85 was probably running reasonably close to peak horsepower while the O-200 was probably a fair bit short - essentially "overpropped" for this test. A flatter prop that let the engine wind up closer to peak hp would have increased the static thrust. How much? Heckifiknow.

Oh, just looked at some of the links on the page - they did some dyno testing that showed the torque peak on the O-200 at 2450 and power peak "very close to its rated peak of 2750rpm" - and the test above was only at 2332.
 
"Telling"? What it's telling us is that static thrust is a pointless test. The C85 has a red line of 2575 RPM and was running at 2350 rpm (data per above web site) The O-200 has a red line of 2750 and was running at 2332 - higher red line but lower RPM during the test. So the C-85 was probably running reasonably close to peak horsepower while the O-200 was probably a fair bit short - essentially "overpropped" for this test. A flatter prop that let the engine wind up closer to peak hp would have increased the static thrust. How much? Heckifiknow.

Oh, just looked at some of the links on the page - they did some dyno testing that showed the torque peak on the O-200 at 2450 and power peak "very close to its rated peak of 2750rpm" - and the test above was only at 2332.

You're right. I missed that. I had assumed, incorrectly, that they were propping for max RPM using the same ground-adjustable prop they used in the HP/torque tests. Didn't read it closely enough.

Dan
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No...there is not free lunch. That is unless you place no value on your time.

I work 50-60 hours weeks and have a busy weekend schedule. I have NO TIME to play backyard aircraft manufacturer. Even if I did, all the time building and not flying....that would be pure misery.

So while I applaud your skills at building, and am truly happy for you, it is not the answer for everyone.

Why is it that builders seem to think that theirs is the "best" way and all someone has to do is open their eyes and see that?

Your not looking hard enough, find one already built and ready to go.

Dan
 
Your not looking hard enough, find one already built and ready to go.

Dan

OK...help me then. I want a HIGH WING airplane that has the range, useful load, and power of a C182 for less than 75K.

Not some slick, low-wing, fighter-style wannabe aircraft.

Any out there?
 
OK...help me then. I want a HIGH WING airplane that has the range, useful load, and power of a C182 for less than 75K.

Not some slick, low-wing, fighter-style wannabe aircraft.

Any out there?
The closest I can think of in a homebuilt would be a Zenith CH801. Dunno the exact numbers, but I can't think of anything else that even comes close.
 
OK...help me then. I want a HIGH WING airplane that has the range, useful load, and power of a C182 for less than 75K.

Not some slick, low-wing, fighter-style wannabe aircraft.

Any out there?
Wait a little while and the C182 will be down there, the way the prices of planes are falling. I haven't seen (at least the asking) prices for 182s fall as fast as others, but I think it's inevitable. Of course, you're not going to get the fuel burn of a 100HP LSA in a 182:no:!
 
Wait a little while and the C182 will be down there, the way the prices of planes are falling. I haven't seen (at least the asking) prices for 182s fall as fast as others, but I think it's inevitable. Of course, you're not going to get the fuel burn of a 100HP LSA in a 182:no:!

There are already quite a few 182's under $75K. Heck, here's a decent-looking one for $40K!: http://www.theplaneexchange.com/listman/listings/l0175.html

Heck, here's a couple of 182RG's for under $90K, with G430's!

http://www.controller.com/listings/detail.aspx?OHID=1139544
http://www.usedaircraft.com/boardview.cfm?BBSID=15004&GroupID=10&CatCode=C205

(Did I get ya lookin' again? :D)
 
OK...help me then. I want a HIGH WING airplane that has the range, useful load, and power of a C182 for less than 75K.

Not some slick, low-wing, fighter-style wannabe aircraft.

Any out there?


Bearhawk, I'll look around. Do you need 2 or 4 seats?

Dan
 
Murphy Moose

Now that is pretty cool! Though I am not so sure about the radial engine.

Now, of course, the trick would be to find one that is already built and less than 100k!

This is all rhetorical of course as I already own a C182...but I appreciate the insight!
 
Bearhawk, I'll look around. Do you need 2 or 4 seats?

Dan

Seriously...thanks, but honestly do not spend too much time. I already own a C182.

The point of my question is that homebuilts seem to fall into two broad categories: the high-wing "work horses" and the low-wing "fighter wannabes".
 
Seriously...thanks, but honestly do not spend too much time. I already own a C182.

The point of my question is that homebuilts seem to fall into two broad categories: the high-wing "work horses" and the low-wing "fighter wannabes".

My Cougar is far from a low wing fighter, and farther from a high wing work horse. Call it a high wing, high mpg, high fun, traveling machine. Once you go to an experimental it is hard to go back. You get so much more for your money. Then you also get it just the way you like it.

I could not find a Bearhawk anywhere. But think about it, for $70,000.00 you could have a plane set up just the way you want it brand new with a new engine new instruments.

Dan
 
I could not find a Bearhawk anywhere. But think about it, for $70,000.00 you could have a plane set up just the way you want it brand new with a new engine new instruments.
$70K - and several years of nearly fulltime effort. Don't get me wrong, the effort pays off in lots of ways, but not everyone has the time to devote.
 
$70K - and several years of nearly fulltime effort. Don't get me wrong, the effort pays off in lots of ways, but not everyone has the time to devote.

"If you want to build, build. If you want to fly, buy." That's an old saying that's been around homebuilding circles for a long time now. Only about 10% of scratch-build projects are ever finished, and not all of those by the folks who began them. A slightly higher percentage might apply to kits. I have friends who have been working on homebuilt projects for nearly 40 years, and now they're too old to ever fly them if they o finish them.
It takes a lot of time, and the cost is always far higher, too, if you add in all the chasing around looking for stuff.

Dan
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LOL...Dan I had not heard that but I believe in the sentiment. If I am in the hangar I want to be pulling the plane out to go fly, or at worst just "tinkering", not building a plane!
 
"If you want to build, build. If you want to fly, buy." That's an old saying that's been around homebuilding circles for a long time now. Only about 10% of scratch-build projects are ever finished, and not all of those by the folks who began them. A slightly higher percentage might apply to kits. I have friends who have been working on homebuilt projects for nearly 40 years, and now they're too old to ever fly them if they o finish them.
It takes a lot of time, and the cost is always far higher, too, if you add in all the chasing around looking for stuff.

Dan

If your in it to fly but would also like to have an experimental get some help. Find someone who already built what you want and have them help. If you just look into it you will find that it only takes years and years when you try and cut corners. There are no rules that say you cannot have help. You and six other buddies can build a plane. You can put very little time in. When it is done you can buy out your buddies if they no longer want it. You will not get the repairman's certificate but it is not that big a deal anyway.

One other way is to find someone who built what your looking for. And find out if they would like to sell their plane if you paid for all the material for them to build another for them self. You would not take possession until they were done (Two years). Some people take longer than that to find the certified plane they are looking for.

Those that say they want to fly not build, but don't fly because it is too expensive... If you have the money to fly now even though things are high FLY. If you do not have the money to fly now because things are too expensive there are other ways to get in the air.

Dan
 
One other way is to find someone who built what your looking for. And find out if they would like to sell their plane if you paid for all the material for them to build another for them self. You would not take possession until they were done (Two years). Some people take longer than that to find the certified plane they are looking for.

Here in Alberta where so many guys are making a killing on oil, there's a whole industry that has popped up to build kitplanes for guys with lots of money and either no time or no ability. So we see airplanes like Lancair IVPs with Garret TPE331s in them (700 hp turboprop), Glasair IIIs with the same engine, and so on. Sometimes its a Walter turbine, for the poorer owners:)
Millions of bucks for those. But even the ordinary kitplane, like an RV-6 with an O-320 in it that can be built for $35K or so, easily soars to $100K or more once the six or eight months or so of shop time is figured into it. So there's no savings at all, just a quick little airplane for an owner who might go and tell everyone that he built it, which I find rather annoying.
In Canada we have a category called "Owner-Maintenance." It allows the owner of certain older models to re-register them in this category, and it basically gets treated like a homebuilt after that. Many older airplanes are difficult to support, as parts aren't available anymore or are stupidly expensive, and many of those parts are easily built or adapted from other parts. The airplane's resale value drops, but the owner has the choice of losing the money on resale value or endlessly feeding it to a shop to keep it legal. Comes to the same thing, pretty much, with the advantage on the O-M side for the oldest types. Here's a list of qualifying types:
http://www.tc.gc.ca/civilaviation/RegServ/Affairs/cars/Part5/Standards/a507sh.htm

Others can be added at the application of the owner, but they have to fit into this definition:

(e) An aircraft type and model may be included in Appendix H of this Standard, Aircraft eligible for a Special Certificate of Airworthiness - Owner-maintenance?, where:


(i) the aircraft is of a type certified in accordance with Chapters 522 or 523 of the Airworthiness Manual, or an equivalent foreign standard;
(ii) the aircraft type certificate does not authorize more than four occupants;
(iii) the maximum certificated take-off weight (MCTOW) of the aircraft does not exceed 1,814 kg (4,000 pounds);
(iv) the aircraft is of a type and model that has not been manufactured during the 60 months preceding the date of application;
(v) fewer than 10% of Canadian aircraft of the type and model concerned are operating in Canadian commercial air service at the time of application;
(vi) the aircraft type and model is powered by a single, normally aspirated, piston engine, and is unpressurized; and
(vii) except for gliders, powered gliders or aircraft with airframes of wooden construction, the aircraft type and model has a fixed landing gear and a fixed pitch propeller.



Dan
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