4-stroke engine options?

[Badland-F5 Pilot]

I got some more Thump-Air time yesterday!



trim_A1F6E85D-B0AC-4015-BC7C-E324C6D989DC.mp4
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Just noticing, 6 seconds from start of roll to off the ground. Very nice!

Todd

[13brv3]

It was reported on the FB group (horrible format) that his last flight didn't make it over 300 ft. He made an excellent dead stick off airport landing with a broken valve. His ThumpAir is no more. Plane and pilot are safely home and shopping for a new engine.

[Badland-F5 Pilot]

It was reported on the FB group (horrible format) that his last flight didn't make it over 300 ft. He made an excellent dead stick off airport landing with a broken valve. His ThumpAir is no more. Plane and pilot are safely home and shopping for a new engine.

Chris and I have been talking. I really wanted the ThumpAir, or a good four stroke. I like the flight time the four strokes give, plus smoothness. However, the Hirth F23 which is the first engine I was really liking provides 50hp and is very smooth for a two-stroke. It's a boxer style two cylinder where both cylinders fire at the same time. This cancels out almost all vibration. At this point, I'm heading that direction. I hope to pick up some fuel economy by swapping out the twin carbs that come with the engine with two Smart Carb 2 carburetors. We have a member that has an SC2 carb on his Polini, and he loves it. The SC2 carb is a very simple design, and compensates for altitude and air temp. Reports are up to 30% more power and 10% better fuel economy. They aren't cheap is their biggest drawback. Only time will tell how well it'll work.

[fly44d]

It was reported on the FB group (horrible format) that his last flight didn't make it over 300 ft. He made an excellent dead stick off airport landing with a broken valve. His ThumpAir is no more. Plane and pilot are safely home and shopping for a new engine.

Chris and I have been talking. I really wanted the ThumpAir, or a good four stroke. I like the flight time the four strokes give, plus smoothness. However, the Hirth F23 which is the first engine I was really liking provides 50hp and is very smooth for a two-stroke. It's a boxer style two cylinder where both cylinders fire at the same time. This cancels out almost all vibration. At this point, I'm heading that direction. I hope to pick up some fuel economy by swapping out the twin carbs that come with the engine with two Smart Carb 2 carburetors. We have a member that has an SC2 carb on his Polini, and he loves it. The SC2 carb is a very simple design, and compensates for altitude and air temp. Reports are up to 30% more power and 10% better fuel economy. They aren't cheap is their biggest drawback. Only time will tell how well it'll work.

Yep, safe and sound on the ground. I don't know why the valve broke, there is some talk from Chris and Bill that maybe the cam is too aggressive for the RPMs we run at. Anyway, assessing options I can afford.
It was just very cool to see that I reacted immediately and properly when it quit. Phttt, thump, silence. No thinking, just fly, land THERE.
No screaming or panic!

[LA F2 Flyer]

Forced landing done right. You should be proud. I would be...

[Badland-F5 Pilot]

It was reported on the FB group (horrible format) that his last flight didn't make it over 300 ft. He made an excellent dead stick off airport landing with a broken valve. His ThumpAir is no more. Plane and pilot are safely home and shopping for a new engine.

Chris and I have been talking. I really wanted the ThumpAir, or a good four stroke. I like the flight time the four strokes give, plus smoothness. However, the Hirth F23 which is the first engine I was really liking provides 50hp and is very smooth for a two-stroke. It's a boxer style two cylinder where both cylinders fire at the same time. This cancels out almost all vibration. At this point, I'm heading that direction. I hope to pick up some fuel economy by swapping out the twin carbs that come with the engine with two Smart Carb 2 carburetors. We have a member that has an SC2 carb on his Polini, and he loves it. The SC2 carb is a very simple design, and compensates for altitude and air temp. Reports are up to 30% more power and 10% better fuel economy. They aren't cheap is their biggest drawback. Only time will tell how well it'll work.

Yep, safe and sound on the ground. I don't know why the valve broke, there is some talk from Chris and Bill that maybe the cam is too aggressive for the RPMs we run at. Anyway, assessing options I can afford.
It was just very cool to see that I reacted immediately and properly when it quit. Phttt, thump, silence. No thinking, just fly, land THERE.
No screaming or panic!

Absolutely on the immediate reaction. I hope if such a situation ever happens to me, I won't be wasting time with question marks in my head, and instead jump right to Aviate, Navigate, and Communicate. Nicely done sir.

[Bruce_L]

Check out the EOS Quattro 4 stroke. This is marketed as a paramotor engine.

Rated at 30.2 HP. The advertised thrust is 80 kg (about 170-180 lbs)

Fuel consumption is claimed to be less than 3 liters per hour. (no pre-mix oil to buy either)

Revs past 8000 RPM

Not sure if there would be issues running it in a tractor configuration. Exhaust direction maybe????

I saw this engine in flight with you tuber Tucker Gott channel. He likes it,

Seems like its about the same output as a Polini 250 -and a tad under the output of the 303.

There are some BL 103s flown with the Polini air cooled 200 out there.

[Badland-F5 Pilot]

Check out the EOS Quattro 4 stroke. This is marketed as a paramotor engine.

Rated at 30.2 HP. The advertised thrust is 80 kg (about 170-180 lbs)

Fuel consumption is claimed to be less than 3 liters per hour. (no pre-mix oil to buy either)

Revs past 8000 RPM

Not sure if there would be issues running it in a tractor configuration. Exhaust direction maybe????

I saw this engine in flight with you tuber Tucker Gott channel. He likes it,

Seems like its about the same output as a Polini 250 -and a tad under the output of the 303.

There are some BL 103s flown with the Polini air cooled 200 out there.

I think I saw the same engine Bruce. I follow Tucker, and he was rather happy with the torque out of the engine too, plus saying it responded quicker to the throttle. Good point about the tractor pull. I've seen many PGP engines that can't handle being reverse mounting. Tucker also said it's very smooth from idle on up. The only issue I see with that engine, if it can be used in a tractor pull configuration, is that the HP is a little low for my needs. Some of the things I want to do will need 8,000+ feet altitude capability. I wonder if the 30hp will be enough to pull a Badland aircraft to that altitude? The less than 1 gallon per hour burn rate is really a good draw to that engine. Imagine flying 3 to 4 hours with plenty left in reserve!

[Bruce_L]

8000 feet AGL huh? Just save some space for a turbo and an intercooler when you mount your motor. Easy fix!

Be sure to contact ATC before you enter Class A airspace.

Don't forget your oxygen bottle too. Thank goodness for titanium huh?

[Badland-F5 Pilot]

8000 feet AGL huh? Just save some space for a turbo and an intercooler when you mount your motor. Easy fix!

Be sure to contact ATC before you enter Class A airspace.

Don't forget your oxygen bottle too. Thank goodness for titanium huh?

The good part is I only need to reach that altitude once during the flight I want to do, but with the F5, it may be possible. Now you know why I need the 50hp out of that F23!

I'll have to figure out how to connect the JATO's on the back of the plane to get into Class A Oh crap, but then I have to also figure out how to stay below VNE!

What, my CPAP won't work for oxy? Dang, another issue to have to figure out!