Hello from an aspiring pilot and experienced DIYer

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blane.c

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Engine depends on airplane design to extent that cubic inches come in to play, not all hp is the same the way a airplane demands power so a higher rpm engine to develop the same power as a lower rpm engine but using PSRU will work fine in some designs but be "wheezing" in other designs. Basically the draggier the airframe the more it is going to like cubic inches which is roughly equivalent to torque @ lower rpm and the cleaner the airframe the better it will accept an engine with a PSRU. It usually comes down to heat, If the higher rpm engine has to work really hard to make the hp then you have to get rid of the heat and that is limited by it's cooling design. So cleaner airframe usually means faster for a given amount of hp and faster means possibly the ability to supply more air for cooling. hp/displacement/torque/rpm/heat/airspeed/acceleration it is a balancing act.

Go through the Hovey pdf on propellers as an exercise just pick an engine a simple one and design one propeller. Much will become clearer.
 

Vigilant1

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I know I am a bit annoying with my engine questions, but the info here is written assuming that you are from a richer more developed country.
I think I understand your situation, and appreciate the reasons for concentrating on the engine (it can be an expensive part of the build and it dictates, to some extent, the plane design you will choose for your project). Motorcycle engines have been looked at a lot for powering homebuilt airplanes. You can find discussion on that by using the search function here at HBA. In a nutshell:
- Any motorcycle engine will require a reduction drive (PSRU) to make enough HP to get a two person airplane airborne. See previous posts on that-ot adds cost, complexity, and may reduce reliability (depending on the model/pairing)
- The BMW horizontal twin motorcycle engines are the most popular motorcycle engine conversions, but still they aren't very numerous in most places. They need a PSRU.
- If you choose an engine that has not been recommended by the aircraft designer, or at the very least has not already been successfully installed and flown for 100 hours by a capable, honest builder who is willing to share his/her experiences with you, then the time to complete your airplane will at least double. Pick a path that is known.
- Dig around a little and learn about your national laws and regulations regarding homebult aircraft. There's no point in going down this road if the regulatory burdens make it impossible.
- Find out what others near you are building. If there is a group, join it.
 

Vigilant1

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Another option to consider: It might not seem likely to you now, but most pilots who own a two seat airplane and who fly for fun usually fly by themselves. Yes, it is a lot of fun to fly with a friend, but as a practical matter, it is often easiest to just go by yourself. A one seat airplane opens up a lot of possibilities for you:
1) A small VW engine is adequate for many single seat aircraft, including the Jodel D9.
2) There are two very good European single seat acft that fly well using an industrial engine (of the kind used for large lawnmowers!). The Spacek SD-1 is available as a kit and the Colomban MC30 can be built from plans. The SD-1 can be built in fewer hours, but the MC30 might cost less. These planes both have easily removable wings and can be towed away in a trailer for storage in the trailer. Price out the cost of storing an aircraft at a hangar at an airport and this might be a big advantage.

This doesn't mean you can't fly with a friend. Just rent a plane (like the Pipestrel you'll train in) for the times you want to do that. A plane like this will be more spacious, can carry more baggage, and be safer than any small two-seater you could build and fly that runs on less than 80 hp. The money you save on hangarage and fuel for a trailered 1 seater will probably pay for renting a 2 seater an hour or two per month.
 

Geraldc

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A website for the Gazaile 2 in Russian.(I view it with Google Chrome translate) But definitely not a 2 year build.
A jodel d18 could be done with the same motor as Gazaile.I think it is a quicker build.
 

FishHawk

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Jan 20, 2021
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A website for the Gazaile 2 in Russian.(I view it with Google Chrome translate) But definitely not a 2 year build.
A jodel d18 could be done with the same motor as Gazaile.I think it is a quicker build.
The Jodel is definitely a much easier build, but whether it can carry that engine safely is very questionable. It's a big difference in weight from a O-200 to an automotive diesel.
 

FishHawk

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Jan 20, 2021
Messages
35
Another option to consider: It might not seem likely to you now, but most pilots who own a two seat airplane and who fly for fun usually fly by themselves. Yes, it is a lot of fun to fly with a friend, but as a practical matter, it is often easiest to just go by yourself. A one seat airplane opens up a lot of possibilities for you:
1) A small VW engine is adequate for many single seat aircraft, including the Jodel D9.
2) There are two very good European single seat acft that fly well using an industrial engine (of the kind used for large lawnmowers!). The Spacek SD-1 is available as a kit and the Colomban MC30 can be built from plans. The SD-1 can be built in fewer hours, but the MC30 might cost less. These planes both have easily removable wings and can be towed away in a trailer for storage in the trailer. Price out the cost of storing an aircraft at a hangar at an airport and this might be a big advantage.

This doesn't mean you can't fly with a friend. Just rent a plane (like the Pipestrel you'll train in) for the times you want to do that. A plane like this will be more spacious, can carry more baggage, and be safer than any small two-seater you could build and fly that runs on less than 80 hp. The money you save on hangarage and fuel for a trailered 1 seater will probably pay for renting a 2 seater an hour or two per month.
Go tell my girlfriend that I'll be building a single seater, and she might kill you. She is more excited than I am, I don't want to crush her dream. She doesn't want to be a pilot, she just wants to be a passenger because she is too panicky and makes bad decisions under pressure according to her (but I secretly agree). That was the biggest problem with choosing a motorcycle. She doesn't want one for herself, but she likes riding. With my A2 licence, no motorcycle could carry me and her(we aren't exactly light, 330 pounds (150kg) combined.
I could try a supercharged VW. A Mini roots type supercharger would be perfect for this, or even a Mercedes twin screw blower geared to match the VW. I could just put the carb in a pressurized box, and I would run it a little rich to cool the engine down. There's no doubt that I can get at least 60hp from the engine at low rpm with the supercharger, but the lubrication issues would give me nightmares. The article from Bob Hoover scared me.
I ruled it out early on due to misconceptions, but all metal seems more attractive now. I have access to a laser, that would greatly reduce my labor. I thought that metal shaping was far more complex than hammer and plywood forms.
 
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FishHawk

Active Member
Joined
Jan 20, 2021
Messages
35
Another option to consider: It might not seem likely to you now, but most pilots who own a two seat airplane and who fly for fun usually fly by themselves. Yes, it is a lot of fun to fly with a friend, but as a practical matter, it is often easiest to just go by yourself. A one seat airplane opens up a lot of possibilities for you:
1) A small VW engine is adequate for many single seat aircraft, including the Jodel D9.
2) There are two very good European single seat acft that fly well using an industrial engine (of the kind used for large lawnmowers!). The Spacek SD-1 is available as a kit and the Colomban MC30 can be built from plans. The SD-1 can be built in fewer hours, but the MC30 might cost less. These planes both have easily removable wings and can be towed away in a trailer for storage in the trailer. Price out the cost of storing an aircraft at a hangar at an airport and this might be a big advantage.

This doesn't mean you can't fly with a friend. Just rent a plane (like the Pipestrel you'll train in) for the times you want to do that. A plane like this will be more spacious, can carry more baggage, and be safer than any small two-seater you could build and fly that runs on less than 80 hp. The money you save on hangarage and fuel for a trailered 1 seater will probably pay for renting a 2 seater an hour or two per month.
Go tell my girlfriend that I'll be building a single seater, and she might kill you. She is more excited than I am, I don't want to crush her dream. She doesn't want to be a pilot, she just wants to be a passenger because she is too panicky and makes bad decisions under pressure according to her (but I secretly agree). That was the biggest problem with choosing a motorcycle. She doesn't want one for herself, but she likes riding. With my A2 licence, no motorcycle could carry me and her(we aren't exactly light, 330 pounds (150kg) combined.
I could try a supercharged VW. A Mini roots type supercharger would be perfect for this, or even a Mercedes twin screw blower geared to match the VW. I could just put the carb in a pressurized box, and I would run it a little rich to cool the engine down. There's no doubt that I can get at least 60hp from the engine at low rpm with the supercharger, but the lubrication issues would give me nightmares. The article from Bob Hoover scared me.
I ruled it out early on due to misconceptions, but all metal seems more attractive now. I have access to a laser. I thought that metal shaping was more complex than hammer and plywood forms.
 
Last edited:

Vigilant1

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You can easily have over 60 HP from a VW Type 1 without need of a turbo or supercharger, even if you live above 1500 meters. A 2180 cc VW can do it without the cost and complexity of forced induction. I fly an aluminum Sonex with a 2180cc VW engine (approx 75 hp for takeoff at sea level), my wife and I (over your stated 330 lbs total--by about 30 lbs) have taken trips with about 40 lbs of other stuff. The Sonex is a sporty little plane, if you wanted to do touring and traveling you might seek out something with a little more wingspan and you could ask less of the engine and get better climb and maybe carry a little more payload. 75 HP for takeoff, 70 hp continuous is all that should be asked of a VW Type 1 if you want reliable service in an airplane. Don't be afraid of lubrication issues, if you are comfortable building an engine from parts you can do, or get someone else to do, those Hoover HVX modifications. The VW has been in airplane use for over 60 years, there are no unknowns with it, as long as you follow the well known path to success. Books, videos are available.
 

Geraldc

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Nov 12, 2011
Messages
527
Location
nz
The Jodel is definitely a much easier build, but whether it can carry that engine safely is very questionable. It's a big difference in weight from a O-200 to an automotive diesel.
An assumption repeated here regularly.
The DV6 Diesel used in Gazaile weighs 107kg with oil, antifreeze, motorized pipes and wiring.
0200 weighs 85kg without accessories.
 

FishHawk

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Jan 20, 2021
Messages
35
An assumption repeated here regularly.
The DV6 Diesel used in Gazaile weighs 107kg with oil, antifreeze, motorized pipes and wiring.
0200 weighs 85kg without accessories.
It has the potential to be milked to 140hp reliably and even 180 with a second turbo. I have it in a Berlingo, and it's a very good engine. I hate the heavy flywheel, but it isn't needed in an aircraft so all is good.
 

TFF

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Apr 28, 2010
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Memphis, TN
What are the rules in the UK about alternative engines? I know they are strict with certified ones, so speculation on certain types might not even be possible like in the US. There might be a narrow list that will work.
 
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