What Engine For a LW and a 270 lb pilot?
- Thread starter magilla
- Start date
Screw
Lubricating & Stimulating
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Screw-In
I just use this:
https://www.lcrcc.net/thrust_calc.htm
and this
https://www.culverprops.com/pitchselection.htm
Screw-Out
I just use this:
https://www.lcrcc.net/thrust_calc.htm
and this
https://www.culverprops.com/pitchselection.htm
Screw-Out
Mike Schallmann
Mad Man MIke
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Ron -
I beg to disagree
--you stated "Most auto conversions will burn alot of fuel per hour period. This is another reason to go Rotax, it burns between 4 to 5 gallons per hour max, throttled back for economy cruise you might get as little as 3 gallons per hour. Most of the bigger Subarus and so on are in the 6-8 gallon per hour burn range. "
In my case I have an EA81 that puts out an honest 100HP. It pulls 430# statis thrust @4800 rpm. (I can get as much as 480 with less pitch and more RPM -but I personally limit my engine at 4800 ) The ALL UP engine weight is 225 # including cooling,carbs, exhaust -less prop. (Its a hand Cranker -but it ALWAYS starts in less than two pulls --hot or cold) At WOT the fuel burn is 5.2 GPH --at cruise it burns 3.8 GPH -- IMHO a 100HP Rotax will fare no better in the fuel economy -or produce no more thrust --the Rotax has the advantage in the weight --- but cost wise the Sub is the clear winner --As far as reliability goes --thats pretty much equal-- but I favor the Sub.
The second auto conversion I have is a 1 LTR 3 cyl GEO -- it weighs 155 ready to fly --including a starter --pulls 345# -the same as a Rotax 582 and the fuel burn is right at 2GPH at cruise--
Neither of these engine has what I would consider to be a high fuel burn -The Sub burns about what my 0-200 (39 Chief) burns (also 100HP)
Larger Subs do burn more fuel -but they put out a lot more power
I beg to disagree
--you stated "Most auto conversions will burn alot of fuel per hour period. This is another reason to go Rotax, it burns between 4 to 5 gallons per hour max, throttled back for economy cruise you might get as little as 3 gallons per hour. Most of the bigger Subarus and so on are in the 6-8 gallon per hour burn range. "In my case I have an EA81 that puts out an honest 100HP. It pulls 430# statis thrust @4800 rpm. (I can get as much as 480 with less pitch and more RPM -but I personally limit my engine at 4800 ) The ALL UP engine weight is 225 # including cooling,carbs, exhaust -less prop. (Its a hand Cranker -but it ALWAYS starts in less than two pulls --hot or cold) At WOT the fuel burn is 5.2 GPH --at cruise it burns 3.8 GPH -- IMHO a 100HP Rotax will fare no better in the fuel economy -or produce no more thrust --the Rotax has the advantage in the weight --- but cost wise the Sub is the clear winner --As far as reliability goes --thats pretty much equal-- but I favor the Sub.
The second auto conversion I have is a 1 LTR 3 cyl GEO -- it weighs 155 ready to fly --including a starter --pulls 345# -the same as a Rotax 582 and the fuel burn is right at 2GPH at cruise--
Neither of these engine has what I would consider to be a high fuel burn -The Sub burns about what my 0-200 (39 Chief) burns (also 100HP)
Larger Subs do burn more fuel -but they put out a lot more power
magilla
Gyro Project Owner
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Okay - in other words...is 160hp too much for a LW?
Okay - in other words...is 160hp too much for a LW?
Please forgive my idiocy...
I have saved all of the excel files and calculators to my own personal "gyro" folder on my computer - will play with them later.
Looking at the EA-81 turbo that puts out 160 horses....is that too much engine for a LW??
What is the optimum horsepower for a 960 lb LW-3?
I guess I will determine the engine after I figure out what kind of hp I need.
Does that make sense? Heck, if 65hp will get me around same as 160, why do I need 160? How much difference does rotor diameter make with speed/maneuverability/etc? How about prop size/type?
I guess I just don't have a clue - would like to know more, and when the gyro aerodynamic books arrive, i will read them cover to cover.
Ron H also recommended the 72" Warp Drive 3-bladed prop. I guess prop type/chord/length makes a big difference.
I sure wish the web moderators would post a sticky as to truisms for gyros - like rotor rules of thumb, engine rules of thumb, and prop rules of thumb - like this:
x bladed props provide more thrust at lower rpms
y bladed props provide more thrust at higher rpms
x bladed props easier to balance
x bladed props quieter
x blade prop advantages:
y blade prop advantages
wood blade prop advantages/disadvantages
composite blade prop advantages/disadvantages
for x weight, you need y horsepower to move you z mph
optimum loading efficiency for x rotor blades is x.y lbs/sqft
Thanks, and I am learning. Just wish the answers were in a book somewhere or a formula!!!
Spencer
Okay - in other words...is 160hp too much for a LW?
Please forgive my idiocy...
I have saved all of the excel files and calculators to my own personal "gyro" folder on my computer - will play with them later.
Looking at the EA-81 turbo that puts out 160 horses....is that too much engine for a LW??
What is the optimum horsepower for a 960 lb LW-3?
I guess I will determine the engine after I figure out what kind of hp I need.
Does that make sense? Heck, if 65hp will get me around same as 160, why do I need 160? How much difference does rotor diameter make with speed/maneuverability/etc? How about prop size/type?
I guess I just don't have a clue - would like to know more, and when the gyro aerodynamic books arrive, i will read them cover to cover.
Ron H also recommended the 72" Warp Drive 3-bladed prop. I guess prop type/chord/length makes a big difference.
I sure wish the web moderators would post a sticky as to truisms for gyros - like rotor rules of thumb, engine rules of thumb, and prop rules of thumb - like this:
x bladed props provide more thrust at lower rpms
y bladed props provide more thrust at higher rpms
x bladed props easier to balance
x bladed props quieter
x blade prop advantages:
y blade prop advantages
wood blade prop advantages/disadvantages
composite blade prop advantages/disadvantages
for x weight, you need y horsepower to move you z mph
optimum loading efficiency for x rotor blades is x.y lbs/sqft
Thanks, and I am learning. Just wish the answers were in a book somewhere or a formula!!!
Spencer
I dont think speed is a forte of gyroplanes, so personaly I dont give it much attention. I think of them as STOL aircraft that are easy to garage and transport.
You might want to look at the pounds per horsepower that many of these machines are carrying, and at around 7 to 12 pounds / HP I dont think you would be far off the mark.
You might want to look at the pounds per horsepower that many of these machines are carrying, and at around 7 to 12 pounds / HP I dont think you would be far off the mark.
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Lubricating & Stimulating
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Maybe I can help with some basic rules of thumb. Yes the thumbs do change from time to time.
1. Everything dealing with Aircraft is a give and take.
a. If you want to increase one part of performance, you suffer on another part. Like to increase climb by re-pitching your prop, your cruise speed will decrease. To increase ergonomics with gadgets, bells and whistles, you add wieght which decreases overall performance....Ect....
2. It is best to use engines, parts and equiptment that have a proven track record. This ensures reliabuility, value, and performance.
3. Don't try and take it all in at once, you'll fry your brain. There is no need for you to figure out best prop, Rotors ect. when you don't have an engine, airframe or otherwise.
Lets start at the beginning and go from there. I'll take you down a road you may enjoy. Next post.
Screw-Out
Maybe I can help with some basic rules of thumb. Yes the thumbs do change from time to time.
1. Everything dealing with Aircraft is a give and take.
a. If you want to increase one part of performance, you suffer on another part. Like to increase climb by re-pitching your prop, your cruise speed will decrease. To increase ergonomics with gadgets, bells and whistles, you add wieght which decreases overall performance....Ect....
2. It is best to use engines, parts and equiptment that have a proven track record. This ensures reliabuility, value, and performance.
3. Don't try and take it all in at once, you'll fry your brain. There is no need for you to figure out best prop, Rotors ect. when you don't have an engine, airframe or otherwise.
Lets start at the beginning and go from there. I'll take you down a road you may enjoy. Next post.
Screw-Out
Screw
Lubricating & Stimulating
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First, lets decide on a gyro to start the project. Single or two place. It looks to me that you have decided on a LittleWing. Good choice, but you have to understand that building a Little Wing is a major undertaking and will require lots of time and patients.
Bang for the buck is what alot of this is all about. As far as build and money, the differance between a two place and single is not that much. You'll pay a little extra for the engine but other than that, the cost to build should be pretty close. I'd go for the two place because the of the value differance when it's all said and done.
Frank Darby build a single LW-3 with the radial and is trying to sell it for 35k. I think this represents slightly less than his investment plus time, but I don't know many folks willing to pay that much for a single place machine.
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First, lets decide on a gyro to start the project. Single or two place. It looks to me that you have decided on a LittleWing. Good choice, but you have to understand that building a Little Wing is a major undertaking and will require lots of time and patients.
Bang for the buck is what alot of this is all about. As far as build and money, the differance between a two place and single is not that much. You'll pay a little extra for the engine but other than that, the cost to build should be pretty close. I'd go for the two place because the of the value differance when it's all said and done.
Frank Darby build a single LW-3 with the radial and is trying to sell it for 35k. I think this represents slightly less than his investment plus time, but I don't know many folks willing to pay that much for a single place machine.
Next Post
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Lubricating & Stimulating
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I don't know if your a builder or an assembler. If your a builder, buy a set of plans from Ron and put your airframe together and don't worry about anything but the airframe untill you are done.
If your not a builder, I think Ron gets $3500 for an airframe. But this does not include landing gear, controls systems, tail feathers, seats, all brackets welded, stringers, doors, ect. All you get is a basic airframe, However, Ron will do all of the above for about another 3k. Ron is a nice guy and he will build as much as you can pay for.
As far as engines go. Ron told me that the Subaru engines are too heavy. Therefore, the Rx-7 and other autoconversions are also too heavy. The VW and the Rotec radial are pushing the limits but are within limits. BTW, you really need to settle on an engine prior to building the airframe because of landing gear placement and firewall width. Ron Recommends and so do most people on this forum Rotax engines. They are proven and reliable. Hirth is also another good choice. I think Ron runs a Hirth on his 2 place. Outside of Rotax, Hirth, and Rotec Radial, anything you do will be experimental because no one has done it yet.
By going with Rotax, Hirth or Rotec, you can talk to people (like Ron) who are running these applications (on a LittleWing) to select redrives and props. By going on your own, the selections will be between you, the engine manufacturer, and the prop company. This can get kinda scary because of the amounts of money and not know if it will work well or not.
Always build light and don't add anything you don't need, and you'll be happy.
Rotor size is determined by Pounds per square foot. Every Blades Manufacturer has differant recommendations for optimum pounds per sqare foot. I like Dragon Wing blades. They are light, inexpensive (Compared to other blade co.) and have very close performance to the 5k Sportcopter blades.
But the good news is you don't have to worry about blades until you bird is built and complete. Until it is built and complete, your not going to have a weight to figure out blade size. The better news is when dealing with blades Co. like Dragon wing, all you got to give Ernie is the all up flying wieght of the machine, less the wieght of the blades, and Ernie will figure it out and send you the blades. For example. Take a bath room scale, put it under each wheel. Add all together. Wiegh yourself, and add to the machine wieght. Then take you fuel capacilty and multiply at 6 lbs per gallon. Add that into your figure and should have an all up flying wieght less blades. Ernie will figure it out. I think DW Blades are optimum at 1.3 lbs per Square ft.
I hope this helps, Baby steps, baby steps.
Screw-Out
I don't know if your a builder or an assembler. If your a builder, buy a set of plans from Ron and put your airframe together and don't worry about anything but the airframe untill you are done.
If your not a builder, I think Ron gets $3500 for an airframe. But this does not include landing gear, controls systems, tail feathers, seats, all brackets welded, stringers, doors, ect. All you get is a basic airframe, However, Ron will do all of the above for about another 3k. Ron is a nice guy and he will build as much as you can pay for.
As far as engines go. Ron told me that the Subaru engines are too heavy. Therefore, the Rx-7 and other autoconversions are also too heavy. The VW and the Rotec radial are pushing the limits but are within limits. BTW, you really need to settle on an engine prior to building the airframe because of landing gear placement and firewall width. Ron Recommends and so do most people on this forum Rotax engines. They are proven and reliable. Hirth is also another good choice. I think Ron runs a Hirth on his 2 place. Outside of Rotax, Hirth, and Rotec Radial, anything you do will be experimental because no one has done it yet.
By going with Rotax, Hirth or Rotec, you can talk to people (like Ron) who are running these applications (on a LittleWing) to select redrives and props. By going on your own, the selections will be between you, the engine manufacturer, and the prop company. This can get kinda scary because of the amounts of money and not know if it will work well or not.
Always build light and don't add anything you don't need, and you'll be happy.
Rotor size is determined by Pounds per square foot. Every Blades Manufacturer has differant recommendations for optimum pounds per sqare foot. I like Dragon Wing blades. They are light, inexpensive (Compared to other blade co.) and have very close performance to the 5k Sportcopter blades.
But the good news is you don't have to worry about blades until you bird is built and complete. Until it is built and complete, your not going to have a weight to figure out blade size. The better news is when dealing with blades Co. like Dragon wing, all you got to give Ernie is the all up flying wieght of the machine, less the wieght of the blades, and Ernie will figure it out and send you the blades. For example. Take a bath room scale, put it under each wheel. Add all together. Wiegh yourself, and add to the machine wieght. Then take you fuel capacilty and multiply at 6 lbs per gallon. Add that into your figure and should have an all up flying wieght less blades. Ernie will figure it out. I think DW Blades are optimum at 1.3 lbs per Square ft.
I hope this helps, Baby steps, baby steps.
Screw-Out
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Lubricating & Stimulating
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Oh, I almost forgot. Because to the extensive build and overall size of the project, I don't recommend the LW as a first Gyro.
I do recommend you hooking up with someone in your area for a ride to see of you'll like #1. If you do and want to join our wacky sport, I sugest your first gyro be a small single place machine like the Dominator. If you wiegh less than 200lbs I recomend the UltaWhite. If you wiegh between 200lbs and 270lbs I recommend the Dominator with a Rotax 582. If you wiegh more than than 270lbs, I recommend you loose wieght.
Gyro Bees are also good First Time Gyros, but a Dominator whore.
Screw-Out
Oh, I almost forgot. Because to the extensive build and overall size of the project, I don't recommend the LW as a first Gyro.
I do recommend you hooking up with someone in your area for a ride to see of you'll like #1. If you do and want to join our wacky sport, I sugest your first gyro be a small single place machine like the Dominator. If you wiegh less than 200lbs I recomend the UltaWhite. If you wiegh between 200lbs and 270lbs I recommend the Dominator with a Rotax 582. If you wiegh more than than 270lbs, I recommend you loose wieght.
Gyro Bees are also good First Time Gyros, but a Dominator whore.
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Brent_Brown
Platinum Member
Victor 1 3100 euros
Victor 2 5200 euros
Price list start Italy + shipping
today 1.18 to 1 euro to dallars what is shipping??????
Victor 2 5200 euros
Price list start Italy + shipping
today 1.18 to 1 euro to dallars what is shipping??????
magilla
Gyro Project Owner
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Screw - You!!
Ha! I appreciate all of the advice. Makes a lot of sense...
But...
I'm sold on the tractor. I don't want to argue with anyone, but PIO/PPO too big a risk with a pusher (for me). My mind is made up on that one.
As far as single seat vs. two place: I agree with you except: with the 2-place LW, you sit in the very back and can't see diddly. even with no other passenger in the front seat. I don't like that. With the LW-3, you are in front!! (please tell me that you can adjust and sit in front on the LW-4, and I'll go the two-seat route...
I essentially want to build a wider (30") frame and stretch the LW-3 to LW-4 proportions, but it will still be a single seater (with extra room in the back). Trying to keep it under 1000lbs.
I am going up to Ron Menzie's in Searcy in about a month to start my gyro certificate. I have 2000 hrs of helo time, and the transition shouldn't be that difficult (but what do I know?). I get autorotation completely - and understand glide angle from first hand experience - the UH-1 is MUCH more forgiving than a UH-60 with its high inertia rotors...
As to build or buy: Ron Herron isn't taking orders right now for frames, or else I would order one complete for the 6500. I am going to go out and buy a welder, and build one myself - I'm not a welder yet, but figure I can learn while I build my trailer for the LW. Not afraid to try new things...and since I am a maintenance test pilot, I like the experimentation and testing aspect. Plus, I can say that I built it myself...even if I drive to Ron H's every other day to make sure that I am doing it right...
I was just afraid of starting down the wrong track and laying out 15k for an engine and 3k for a prop that didn't work together. And even though I am not "cheap," I am looking for doable alternatives. If the turbo Suzuki engine with redrive can replace the Rotax for 1/4 the price, I am willing to try it. If I end up having to put in a VW like yours because the Suzuki didn't work out...well... I'll look to you for your "lessons learned."
BTW - I noticed in your pics you have a higher/offset thrust with your redrive - was that the reason you got an 80" prop, or did you select the prop based on the rpm's for the engine, and then put the reduction unit higher?
advantages to an 80" two-bladed prop?
Please, keep the thoughts coming!!! I am learning a lot, especially going over my decisions now as I read your rules of thumb.
By the way, those pics of the LW-3 are awesome!!! Would like to get plans for the trailer!!!
Ha! I appreciate all of the advice. Makes a lot of sense...
But...
I'm sold on the tractor. I don't want to argue with anyone, but PIO/PPO too big a risk with a pusher (for me). My mind is made up on that one.
As far as single seat vs. two place: I agree with you except: with the 2-place LW, you sit in the very back and can't see diddly. even with no other passenger in the front seat. I don't like that. With the LW-3, you are in front!! (please tell me that you can adjust and sit in front on the LW-4, and I'll go the two-seat route...
I essentially want to build a wider (30") frame and stretch the LW-3 to LW-4 proportions, but it will still be a single seater (with extra room in the back). Trying to keep it under 1000lbs.
I am going up to Ron Menzie's in Searcy in about a month to start my gyro certificate. I have 2000 hrs of helo time, and the transition shouldn't be that difficult (but what do I know?). I get autorotation completely - and understand glide angle from first hand experience - the UH-1 is MUCH more forgiving than a UH-60 with its high inertia rotors...
As to build or buy: Ron Herron isn't taking orders right now for frames, or else I would order one complete for the 6500. I am going to go out and buy a welder, and build one myself - I'm not a welder yet, but figure I can learn while I build my trailer for the LW. Not afraid to try new things...and since I am a maintenance test pilot, I like the experimentation and testing aspect. Plus, I can say that I built it myself...even if I drive to Ron H's every other day to make sure that I am doing it right...
I was just afraid of starting down the wrong track and laying out 15k for an engine and 3k for a prop that didn't work together. And even though I am not "cheap," I am looking for doable alternatives. If the turbo Suzuki engine with redrive can replace the Rotax for 1/4 the price, I am willing to try it. If I end up having to put in a VW like yours because the Suzuki didn't work out...well... I'll look to you for your "lessons learned."
BTW - I noticed in your pics you have a higher/offset thrust with your redrive - was that the reason you got an 80" prop, or did you select the prop based on the rpm's for the engine, and then put the reduction unit higher?
advantages to an 80" two-bladed prop?
Please, keep the thoughts coming!!! I am learning a lot, especially going over my decisions now as I read your rules of thumb.
By the way, those pics of the LW-3 are awesome!!! Would like to get plans for the trailer!!!
chuter
Platinum Member
When I was considering building a LW 2 place, I didn't like the sit-in-the-back-seat feeling either. I figured I could plan on flying it solo from the front seat, and make a way to attach a small amount of weight at the rear of the aircraft to make it balance.
Not sure how much it would take, but it seems like it shouldn't be to much if it's at the back of that long fuselage.
Not sure how much it would take, but it seems like it shouldn't be to much if it's at the back of that long fuselage.
magilla
Gyro Project Owner
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You mean like adding a fuel pod or whatnot to the rear seat to give you balance? That could be an option...
You could also design it in a way to allow you to sit up front with the passenger in back, maybe by moving the battery further aft.
You wouldn't necessarily want to move the fuel cell to far back - the change in moment / c.g. would be too great as you burned gas...
So, did you end up with the 2-place LW??
What engine do you have?
You could also design it in a way to allow you to sit up front with the passenger in back, maybe by moving the battery further aft.
You wouldn't necessarily want to move the fuel cell to far back - the change in moment / c.g. would be too great as you burned gas...
So, did you end up with the 2-place LW??
What engine do you have?
Brent_Brown
Platinum Member
Not sure but but a side x side tractor would fit all your needs. I know it will be more drag and all but just make it as light as you can fly to have fun.
chuter
Platinum Member
Spencer,
I ended up making my own design tractor; there's more info on other threads, here's a link to a movie of it flying:
Airborne 200 movie
Here's my never-updated website and builder's log:
okiemike
I was thinking maybe a 10-20lb (might take more, I didn't ever put pencil to pad) barbell weight attached close to the tailwheel somehow might be enough. Something easy to remove if you want to fly a passenger.
I ended up making my own design tractor; there's more info on other threads, here's a link to a movie of it flying:
Airborne 200 movie
Here's my never-updated website and builder's log:
okiemike
I was thinking maybe a 10-20lb (might take more, I didn't ever put pencil to pad) barbell weight attached close to the tailwheel somehow might be enough. Something easy to remove if you want to fly a passenger.
Screw
Lubricating & Stimulating
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Magilla,
I am stepping out on my own with this engine. Ron has a LW single place with a VW, and so do a few others, but no one has put the engine combo I've got on a 2 place yet.
As far as the prop goes, the engine and the available motor mount would put the pulley (normal prop application) 2 inches below the thrustline. The redrive I'm using is 5 inches taller than the pulley, therefore my prop will be 3 inches above the thrustline. Ron says the Radial's prop is dead center of the thrustline and he can safely swing a 74 inch prop. Therefore the 80 inch prop I'm swinging should give me the same prop clearance as a 74 on the radial.
Great Plains recommends a 2 blade wood prop for their engines, and that is all I've ever used. I hooked up with Lonnie Prince of Prince prop (Leading Manufacturer of performance props) https://www.princeaircraft.com/index.html and givin my slow turning prop, he actually recommended an 83x50 prop. Limited to 80 inches we decided a good starting point would be the 80x50 and he is willing to work with me on any adjustments (pitch wise) that may be needed.
Keep in mind that my engine max RPM is 4250. With a 2:1 redrive the max Prop RPM will be 2125. I'm only expexting to get the engine up to about 3900rpms on the ground and cruise rpm is 3200, therefore my prop rpms will be basically between 1600 and 1950. That's kinda slow, and that's why the big prop with lots of pitch.
That's the engine and prop question. Trust me, if I had the money I would have gone with the radial or the rotax 912s.
Screw-Out
Magilla,
I am stepping out on my own with this engine. Ron has a LW single place with a VW, and so do a few others, but no one has put the engine combo I've got on a 2 place yet.
As far as the prop goes, the engine and the available motor mount would put the pulley (normal prop application) 2 inches below the thrustline. The redrive I'm using is 5 inches taller than the pulley, therefore my prop will be 3 inches above the thrustline. Ron says the Radial's prop is dead center of the thrustline and he can safely swing a 74 inch prop. Therefore the 80 inch prop I'm swinging should give me the same prop clearance as a 74 on the radial.
Great Plains recommends a 2 blade wood prop for their engines, and that is all I've ever used. I hooked up with Lonnie Prince of Prince prop (Leading Manufacturer of performance props) https://www.princeaircraft.com/index.html and givin my slow turning prop, he actually recommended an 83x50 prop. Limited to 80 inches we decided a good starting point would be the 80x50 and he is willing to work with me on any adjustments (pitch wise) that may be needed.
Keep in mind that my engine max RPM is 4250. With a 2:1 redrive the max Prop RPM will be 2125. I'm only expexting to get the engine up to about 3900rpms on the ground and cruise rpm is 3200, therefore my prop rpms will be basically between 1600 and 1950. That's kinda slow, and that's why the big prop with lots of pitch.
That's the engine and prop question. Trust me, if I had the money I would have gone with the radial or the rotax 912s.
Screw-Out
Screw
Lubricating & Stimulating
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Screw-In
As far as the 2 place vs single.
In any 2 place machine, you'll always have a major wieght change between flying single or 2 up, therefore, you build it to balance so that the changes in wieght are always on the CG. For the 2 place the CG is the front seat. On a pusher, the CG is the rear seat.
After you get some time in the rear seat, you'll get used to it. Your forward visability on takeoff and landings are limited, but not nessessary.
If a single is what you what, I'd give heavy consideration to contacting Frank Darby (770) 533-9531 and try to purchase his LW. I've seen it up close, and he spared no expense and did a super, super job. Frank lost his medical is why he is not flying it. The aircraft is new and has yet to make it's maden flight. A few of us at Bensen days and SX days were so hoping he would let Ron Awad take her out.
Screw-Out
As far as the 2 place vs single.
In any 2 place machine, you'll always have a major wieght change between flying single or 2 up, therefore, you build it to balance so that the changes in wieght are always on the CG. For the 2 place the CG is the front seat. On a pusher, the CG is the rear seat.
After you get some time in the rear seat, you'll get used to it. Your forward visability on takeoff and landings are limited, but not nessessary.
If a single is what you what, I'd give heavy consideration to contacting Frank Darby (770) 533-9531 and try to purchase his LW. I've seen it up close, and he spared no expense and did a super, super job. Frank lost his medical is why he is not flying it. The aircraft is new and has yet to make it's maden flight. A few of us at Bensen days and SX days were so hoping he would let Ron Awad take her out.
Screw-Out
RHerron
Senior Member
Solo from front
Solo from front
Hello everyone,
I thought I would mention that I am building a custom 2-seat Little Wing for a customer in Italy. Currently, I have all the welding completed including the engine mount. It will use a 914 Rotax.
I am working on a moveable/foldable mast with linkages that adjust the head angle for any mast position selected. It can be adjusted to accommodate solo from the front or rear. Adjustment takes less than one minute and no tools are required. By the way, this system is already built and installed on the bare fuselage for final fitting before paint.
The front seatback is adjustable to allow for more legroom in the front when flying solo. Also, the cabin is 28 inches wide, two inches wider than standard.
I will eventually add this mast system to the drawing package once it is tested.
Solo from front
Hello everyone,
I thought I would mention that I am building a custom 2-seat Little Wing for a customer in Italy. Currently, I have all the welding completed including the engine mount. It will use a 914 Rotax.
I am working on a moveable/foldable mast with linkages that adjust the head angle for any mast position selected. It can be adjusted to accommodate solo from the front or rear. Adjustment takes less than one minute and no tools are required. By the way, this system is already built and installed on the bare fuselage for final fitting before paint.
The front seatback is adjustable to allow for more legroom in the front when flying solo. Also, the cabin is 28 inches wide, two inches wider than standard.
I will eventually add this mast system to the drawing package once it is tested.
magilla
Gyro Project Owner
- Joined
- Dec 17, 2005
- Messages
- 546
- Location
- Little Rock, AR
- Aircraft
- UH-1H / UH-60A
- Total Flight Time
- 2000+ RW
Chuter, that is one sweeeeeeeeeeeet gyro and a great video!! What an accomplishment! My hat's off to you.
I just got Abbot's two books on gyroplane flying and design, as well as Igor Bensen's "A Dream of Flight" and the Rotorcraft flying handbook. I should be busy reading for a while!
Screw - I'm with you. Right now, I can build one over a two-year period - just don't have 35k to lump out at one time. Wonder if I could take a loan at the bank??
I think that I am going to have to space out the build and the assembly so that I can afford it a little better.
It's one of the primary reasons I am looking at engine alternatives.
By the way, this forum is the best!!
Two questions:
1) aerodynamically, what is advantage of two blade prop to three? Wouldn't you want more blades biting into the air? Is a four-bladed prop an option for a gyro?
2) Is it feasible to use an adjustable pitch prop to get you both take off thrust and then feather to reduce drag for higher cruise speeds?
I think I need to write all of my q's down and go sit down with Ron H for a while and pick his brain.
Edit:
Ron - great news!!
That sounds like the next evolution in the design! Hmm..now I am confused again as to whether I need the LW-3 or LW-5?? Ha!
Will the new head design be around to see mid-January when I plan to visit you and your LW's at 1M1???
Spencer
I just got Abbot's two books on gyroplane flying and design, as well as Igor Bensen's "A Dream of Flight" and the Rotorcraft flying handbook. I should be busy reading for a while!
Screw - I'm with you. Right now, I can build one over a two-year period - just don't have 35k to lump out at one time. Wonder if I could take a loan at the bank??
I think that I am going to have to space out the build and the assembly so that I can afford it a little better.
It's one of the primary reasons I am looking at engine alternatives.
By the way, this forum is the best!!
Two questions:
1) aerodynamically, what is advantage of two blade prop to three? Wouldn't you want more blades biting into the air? Is a four-bladed prop an option for a gyro?
2) Is it feasible to use an adjustable pitch prop to get you both take off thrust and then feather to reduce drag for higher cruise speeds?
I think I need to write all of my q's down and go sit down with Ron H for a while and pick his brain.
Edit:
Ron - great news!!
That sounds like the next evolution in the design! Hmm..now I am confused again as to whether I need the LW-3 or LW-5?? Ha!
Will the new head design be around to see mid-January when I plan to visit you and your LW's at 1M1???
Spencer
Last edited:
Brent_Brown
Platinum Member
John they make that redrive in a 1.6 to 1 if you feel the prop is to slow for a 74" prop. My MZ has a 73" and a 2.88 to 1 gear max rpm 5800= 2013 I fly back at 5300= 1840 slow prop.
My 670 has a 74" prop and a 3.47 to 1 max rpm 6800= 1960.
My 670 has a 74" prop and a 3.47 to 1 max rpm 6800= 1960.
