50 HP engine recommendations

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Waltcloudt

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New to this having wanted to build a plane most of my life but realize the engine is the most expensive part of an ultralight. Looked at a vendor site selling a world of small engines and am now very confused.

I don't want to spend any more than I have to as funds are limited as I'm retired and on a relatively fixed income. I'm 74 and in good health. Is it too late to start? I have a pilot license from the '80s.

I'm considering a couple planes, the Kolb Ultra Star and the Affordaplane. Assume the engines would require a reduction gear. I like the US folding wings and the no welding of the Affordaplane. Does the AP have a folding wing option?

I would appreciate any tips on selecting an engine and any other advice.
 

Wayne

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Welcome Walcloudt!
Of the two options I would go with the Kolb if it were me making the decision as the manufacturer has a long and successful history, which should make it a lot easier for you to get the best engine advice (most likely from them or the plans), parts, tech support, etc. Lots of community/forum help as well - several members know the Kolb on HBA.

If you use the advanced search feature you will find much info on the Affordaplane. Not a choice I would personally make. Jon Croke, an author of many aircraft builds is putting one together. Here is the thread on HBA Jon Croke builds Afford A Plane videos

Also - make sure you have a firm grasp of the Part 103 guidelines if you are going ultralight. The max weight of a powered Ultralight, with no recovery shoot, is 254 pounds and 5 gals of fuel. Since you have your license already, and will need to get some instruction to de-rust, you might end up flying under the Light Sport category which gives you loads of flexibility in what you can fly.
 

cluttonfred

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Welcome! It's definitely not too late to start. 50 hp is quite a bit if you are sticking with U.S. Part 103 and since you mention avoiding welding you are probably talking about scratch building from plans. Maybe tell us more about where you are, what sort of flying you want to do, what type of construction you prefer, and what budget you have in mind? Then we can be more helpful.
 

ToddK

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At 74, go buy a partially completed minimax or some other bird you can have flying soon. A quicksilver or weedhopper are also good options. Get one that is just barely not flying and get it in the air. Look at a rotax 503 (used and rebuilt, or a new mz202.
 

Daleandee

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You're still a young man! A friend recently bought a hurricane 103 with a 447 Rotax. It was quite a deal he got from a friend of mine that needed to sell it quick. It's a 40 HP engine and for a two stroke they are reliable if properly maintained. ToddK mentioned the MZ202 engines and we have one here on a Flightstar. Not much time on it but seems to be a good little engine also.

My friend is having a blast flying the Hurricane around while he works toward his Sport certificate.

Welcome to the forum!
 
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rv7charlie

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Have I got a deal for you. ;-)

Would you be interested in an original Kolb Twinstar? Frame-up restored about 3 years ago and sitting in my hangar ever since. New Black Max wheels/brakes with 6x6 aircraft tires. Rotax 503 with unknown hours but runs fine. I thought I'd be flying it to save gas vs my RV6, but I've discovered that I can putter around in the -6 at just over 5 gal/hr, so no real fuel savings in the Kolb. $3500 and it's yours.

Plane is located at Slobovia Outernational (MS71), just north of Jackson MS.

Shoot me a PM if you're interested.

Charlie
 

David L. Downey

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Have I got a deal for you. ;-)

Would you be interested in an original Kolb Twinstar? Frame-up restored about 3 years ago and sitting in my hangar ever since. New Black Max wheels/brakes with 6x6 aircraft tires. Rotax 503 with unknown hours but runs fine. I thought I'd be flying it to save gas vs my RV6, but I've discovered that I can putter around in the -6 at just over 5 gal/hr, so no real fuel savings in the Kolb. $3500 and it's yours.

Plane is located at Slobovia Outernational (MS71), just north of Jackson MS.

Shoot me a PM if you're interested.

Charlie
Wow rv7charlie! wish I did not already have an US and a Phantom! I love the Twinstar. Open cockpit or faired? Is it in current registration and condition inspection? Do you have a trailer for it?
and. to the OP: I wonder what John Bolding would charge to weld up the cage and other steel bits on the US? I have know a bunch of people who own(ed) Ultrastars and then other true ultralights and to a man they love the US. I knew Homer and his crew personally back when the Flyer and US were the rage. Honest designer who cared about getting his work analyzed for stresses.
 

rv7charlie

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Hi David,
It's the 'original', with just a little fairing over your feet & legs. Registration is current; last condition inspection was after I did the restoration several years ago. Been hangared since then. No trailer available, but it will fit on almost anything with the wings folded. I do have someone that's interested in it, but I'll be happy to put your name on the list. ;-)
 

Waltcloudt

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Oct 13, 2021
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Welcome Walcloudt!
Of the two options I would go with the Kolb if it were me making the decision as the manufacturer has a long and successful history, which should make it a lot easier for you to get the best engine advice (most likely from them or the plans), parts, tech support, etc. Lots of community/forum help as well - several members know the Kolb on HBA.

If you use the advanced search feature you will find much info on the Affordaplane. Not a choice I would personally make. Jon Croke, an author of many aircraft builds is putting one together. Here is the thread on HBA Jon Croke builds Afford A Plane videos

Also - make sure you have a firm grasp of the Part 103 guidelines if you are going ultralight. The max weight of a powered Ultralight, with no recovery shoot, is 254 pounds and 5 gals of fuel. Since you have your license already, and will need to get some instruction to de-rust, you might end up flying under the Light Sport category which gives you loads of flexibility in what you can fly.
I wanted to stay ultralight, so 50 hp is probably too heavy. I really like the US design and am willing to learn welding. The AP appealed because it seemed easily built from the videos.
I live in N Chesterfield, VA and have a small airport close by but haven’t checked if they will allow an ultralight to fly there. I have seen sport types flying there.
I’m thinking about joining the local EAA chapter as a resource.
I just want to be able to fly low & slow for fun. No plans to travel.
 

Waltcloudt

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Oct 13, 2021
Messages
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Have I got a deal for you. ;-)

Would you be interested in an original Kolb Twinstar? Frame-up restored about 3 years ago and sitting in my hangar ever since. New Black Max wheels/brakes with 6x6 aircraft tires. Rotax 503 with unknown hours but runs fine. I thought I'd be flying it to save gas vs my RV6, but I've discovered that I can putter around in the -6 at just over 5 gal/hr, so no real fuel savings in the Kolb. $3500 and it's yours.

Plane is located at Slobovia Outernational (MS71), just north of Jackson MS.

Shoot me a PM if you're interested.

Charlie
Thanks, but I don’t want a 2 place. Sounds like a terrific deal for someone. Should sell quickly.
 

Dana

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The Ultrastar was designed for the 35HP Cuyuna engine with 2:1redrive and it does quite well with that. A 447 is anther good choice. A half VW would likely work well but it might be too wide to let the wings fold.
 

Waltcloudt

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The Ultrastar was designed for the 35HP Cuyuna engine with 2:1redrive and it does quite well with that. A 447 is anther good choice. A half VW would likely work well but it might be too wide to let the wings fold.
Thanks for specific info. What size prop? 1/2 VW, from what I know would be heavier and more expensive than a 2 cycle.
I saw video of a US doing aerobatics. Did it have any mods to do that?
 

Dana

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For the Cuyuna with a 2:1 redrive, a 50x30 prop. China weighs 85#, same as the Mosler half VW I had on my Fisher.
 

Brünner

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Thanks, but I don’t want a 2 place. Sounds like a terrific deal for someone. Should sell quickly.
Having a 2 seats doesn't necessarily mean to carry another person, you can use the other seat for food, water, stuff, during long x-countries....wink wink.
 

Heliano

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Waltcloudt, not late at all to start! Working on a dream will make you healthier and mentally younger. I´m 71, retired (still do some consulting service, but retired as pilot/engineer employee). Allow me to suggest you to have a look at the book "Flight of a Lifetime" by William Randolph. He's built an RV after he recovered from a throat cancer, and flew solo around the world when he was 76! As for welding, TIG or gas welding is a little tricky. Learning the nedded skills to do decent welding is challenging but not impossible, once you learn that it is very rewarding. But keep two things in mind: 1) It takes time; 2) Find a professional to help you along the learning process.
 

Daleandee

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Having a 2 seats doesn't necessarily mean to carry another person, you can use the other seat for food, water, stuff, during long x-countries....wink wink.
Yep. In my little Challenger sometimes the rear seat had a plastic fuel container with premix in it, other times it would be filled with baggage if planning to spend a few days at a fly-in. Now and then I'd put a student/passenger in there. ;)
 

David L. Downey

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The Ultrastar was designed for the 35HP Cuyuna engine with 2:1redrive and it does quite well with that. A 447 is anther good choice. A half VW would likely work well but it might be too wide to let the wings fold.
Dana, have you ever heard of a 1/2 VW in an US? it woudl actually fit the need pretty well: I never even considered it...would a direct drive 37hp Hummel even turn the 50-53" diameter prop the US uses? and, I wonder what the fuel burn would be compared to the Cuyuna...after all Range is a pretty sever limitation on 5 US gallons...
 

Dana

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I ran a 54" prop on my Mosler, which was claimed to be 40HP though some question the HP rating. Half VWs usually run very narrow bladed props. Fuel consumption around 2 gph, half of what I saw with the Cuyuna on my US.
 
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