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TFF

Well-Known Member
Wheelbarrow is an interesting conversion to flying machine. I would consider building this. Primary Glider Plans
The plans are cheap, it is successful flying, and a few have been converted to engines. I say first build it completely as a glider and before you cover it, decide how to finish it. It will take a lot of guesswork out of how to build something and at the same time creating some new questions.

DavidBooks

Member
I'll consider it, but (however idiotic it may be) I am quite married to the idea of creating and designing my own plane.

Protech Racing

Cuyuna 215 , Rotax 277, Big single Honda clones, The 627 V twin, all could be well under 1500$. Use some sort of redrive on the first 3. When you lack cash, you must be innovative. Stubborn helps but often will kill you. TFF Well-Known Member Designing your second plane when you have experience of what you liked and what you don’t from a design from the first is helpful. No one says you can’t build another. Yours is very similar already to this other one. It can fill in the blanks on what yours needs. Stephen Asman Member To answer the original question, here is an engine that is over 15 HP and costs less than$1000:

It has been discussed some here but folks are leary of it because:

1. At 110 lbs it's a bit heavy
2. The 1" PTO shaft might not handle prop loads.
3. Harbor freight's reputation.

Personally, after looking into V-twins, I've decided to go with a 1/2 VW build.

TFF

Well-Known Member
I think I would be more inclined to find a pair of used 150-200cc model plane engines a la CriCri. Converting a lawn engine is not easy without some fancy tools and is going to take more money and expertise to do the conversion. Low horsepower means the plane will need to be lighter than 254 maximum weight. If not I would be more inclined to spend the money on a 1/2VW. That would require being able to machine stuff yourself and not buy off the shelf stuff for that price. $1000 does not go far.$2000 is almost as hard. Hopefully once the airframe is finished a better cash flow situation will help finish it, and there is a long way to go to even get to the point of needing an engine.

Jsample40

Well-Known Member
I have 3ea twin cylinder horizontally opposed KFM aircraft engines in good working order for sale. Complete with factory designed belt reduction, alternators, electric starters, ready to bolt on an ultra light/ home built aircraft. Entire engine package weighs approx. 50 lbs. I flew this model engine for 8 years & found them to be exceptional in design, performance, power to weight ratio. The 25 hp are $1000.00, and the 30 hp is$1500.00. First come, first served. Cash only. Spare parts available.
Jay W. Sample

Turd Ferguson

Does your $1000 price point include a re-drive (if necessary)? jedi Well-Known Member 10 hp Tillitson (dynos at 9.5 hp) 212 cc can be upgraded to 225 cc or purchased complete to go to 17 hp at higher intermittent rpm. Stock 212 is$200 or $270 with electric start. 225 cc purchased complete is$750 IIRC.

My son is working with this engine. His design will use two of the lower power engines with the ability to upgrade if more power is required (or desired). The stock twin engine gives good thrust efficiency without a redrive. It also is suitable with a much less expensive prop. The high rpm upgrade is to much rpm for a direct drive and then requires a much more expensive prop as it is out of the large model aircraft sized prop.

Weight depends on how much stuff you add or remove, etc. so no numbers unless there is much more discussion. It comes down to a $/# equation so each application has it own unique solution if any. Last edited: Vigilant1 Well-Known Member Lifetime Supporter 10 hp Tillitson (dynos at 9.5 hp) 212 cc can be upgraded to 225 cc or purchased complete to go to 17 hp at higher intermittent rpm. Stock 212 is$200 or $270 with electric start. 225 cc purchased complete is$750 IIRC.

My son is working with this engine. His design will use two of the lower power engines with the ability to upgrade if more power is required (or desired). The stock twin engine gives good thrust efficiency without a redrive. It also is suitable with a much less expensive prop. The high rpm upgrade is to much rpm for a direct drive and then requires a much more expensive prop as it is out of the large model aircraft sized prop.

Weight depends on how much stuff you add or remove, etc. so no numbers unless there is much more discussion. It comes down to a $/# equation so each application has it own unique solution if any. Interesting. It looks like these weigh about 40 lbs each, though I'm not sure what is included in that. Surely not a prop hub. Is your son trying to get under US Part 103 weight? Do you know of other folks using these direct drive? IMO, a three-engine plane with these/similar engines would be a fun challenge (something like a micro version of Blane's Tri-Mower idea).$600-$800 for 30 HP isn't bad, 120 lbs is a lot but might be acceptable, and flight on 20 hp (one engine out) might be possible with enough span and attention to weight. The larger singles (Honda clones and B&S of 440cc+) might also be good from$/hp and lbs/hp perspective.
Multi-engine with singles: "Whole lotta shakin' goin on."

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Protech Racing

Well-Known Member
These were used on the Lazair .

REVAN

Well-Known Member
Interesting. It looks like these weigh about 40 lbs each, though I'm not sure what is included in that. Surely not a prop hub.

Is your son trying to get under US Part 103 weight? Do you know of other folks using these direct drive?

IMO, a three-engine plane with these/similar engines would be a fun challenge (something like a micro version of Blane's Tri-Mower idea). $600-$800 for 30 HP isn't bad, 120 lbs is a lot but might be acceptable, and flight on 20 hp (one engine out) might be possible with enough span and attention to weight. The larger singles (Honda clones and B&S of 440cc+) might also be good from $/hp and lbs/hp perspective. Multi-engine with singles: "Whole lotta shakin' goin on." I am trying to be 103 compliant with my design. My Tillotson 212cc test engine has the electric starter and the steel fuel tank on top. It is stock, with the only modification being a prop flange and propeller attached to the engine shaft. On the test stand, I've got about 40 hours on the engine so far. The test engine as it stands weighs in at 42 pounds with oil. I'm intending to just use recoil start on my ultralight (at least in the beginning). Dropping the starter, steel fuel tank and oil from the engine's empty weight should get it down below 39 pounds. Then if I want to shed more weight, I'll replace the iron fly wheel with an aluminum one. That will cost about$100, and should bring the engine+propeller weight down into the 35 to 36 pound range. Cost for the engine with aluminum flywheel and propeller will be around $500 for about 10 Hp, or$50/Hp.

If it is too underpowered, one option is to upgrade to the 225cc engine. I figure I can prop it to de-rate the 17.5 Hp engine down to about 14 or 15 Hp and still direct drive the propeller. This will provide more margin on heat rejection than running it at 17 Hp. The downside is the 225cc engine is more expensive and drinks premium fuel instead of regular. I'll be looking at more like $1000 for engine+propeller, or about$70/Hp. So, for about double the installed cost and also more noise and more expensive fuel, I can get about 40% to 50% more power.

My first choice is to try to build a design that is efficient enough to be able to operate effectively with the 10 Hp engines. Hopefully, it will work.

Vigilant1

Well-Known Member
I'm intending to just use recoil start on my ultralight (at least in the beginning). Dropping the starter, steel fuel tank and oil from the engine's empty weight should get it down below 39 pounds. Then if I want to shed more weight, I'll replace the iron fly wheel with an aluminum one. That will cost about $100, and should bring the engine+propeller weight down into the 35 to 36 pound range. Cost for the engine with aluminum flywheel and propeller will be around$500 for about 10 Hp, or $50/Hp. If it is too underpowered, one option is to upgrade to the 225cc engine. I figure I can prop it to de-rate the 17.5 Hp engine down to about 14 or 15 Hp and still direct drive the propeller. This will provide more margin on heat rejection than running it at 17 Hp. The downside is the 225cc engine is more expensive and drinks premium fuel instead of regular. I'll be looking at more like$1000 for engine+propeller, or about $70/Hp. So, for about double the installed cost and also more noise and more expensive fuel, I can get about 40% to 50% more power. My first choice is to try to build a design that is efficient enough to be able to operate effectively with the 10 Hp engines. Hopefully, it will work. Thanks for the helpful info, sounds like a fun project. The relationships between$, HP, and lbs definitely aren't linear, so it can be a challenge to find the best mix.