Side-by-Side Little Wing Build

[Miranda]

Hello All,

My name is Miranda. I just purchased Little Wing plans from Ron Herron, with the express intent of building a Little Wing in the side-by-side configuration. I won't actually begin construction until this summer because I have a couple of other projects I have to finish before then. The delay will give me time to work out the engineering details for side-by-side in the meantime, as well as a couple of other design issues (which affordable engine to use; whether and how to mount stub wings, etc.) that need to be resolved.

I will post ideas I am considering to this thread and, of course, I welcome and look forward to any suggestions, observations, experiences, etc., any of you might want to contribute.

Thanks,

Miranda

 

[Alan_Cheatham]

This may be of interest:

https://www.rotaryforum.com/forum/showthread.php?t=28099&page=2

.

 

[Miranda]

That was an interesting thread. Thanks.

I corresponded with Ron before buying his plans and asked for his thoughts on the feasibility of going side-by-side. I expressed my own concern for the possibility of altering the aerodynamics of the fuselage. He said "At 42" wide, aerodynamics (drag) won't be the biggest issue. In fact, drag may actually be less. (compare a BC-12D to a J-3 Cub). I think you can take the Little Wing prints and build the side view plan and then reshape the top view plan to accommodate your dimensions. Then brace-by-brace, cross-member by cross-member, fill in the blanks."

Ron was more concerned with my intended use of a Subaru conversion to power the aircraft. He said at 220 pounds it was a bit on the heavy side, and strongly recommended I use a Rotax 912 or 914 (100 hp and 150 lbs). I would love to use a Rotax but the price is absolutely out of my budget. Ron said he recommends 100 hp for a 2-place Little Wing to avoid flying at max rpm all the time and to give a margin of reserve power when needed.

I am considering a Revmaster R-2300 (82 hp continuous; 85 hp for 5 min; 170 lbs). I know it is less than Ron's recommended 100 hp, but it has the advantage of being direct drive and not losing any of its rated brake horsepower through a reduction unit. I have to contact Revmaster and see of they are going to offer a turbo model, or if an aftermarket one can be readily added.

I am also considering adding stub wings, as with the McCulloch J-2, to augment lift and permit higher cruise speeds on the same power output - or to permit the same cruising speed on less horsepower. I have run across earlier threads here that discussed the same thing, and apparently some designers have said that adding stub wings was one modification they wish they had incorporated in their original designs.

 

[All_In]

...
I am also considering adding stub wings, as with the McCulloch J-2, to augment lift and permit higher cruise speeds on the same power output - or to permit the same cruising speed on less horsepower. I have run across earlier threads here that discussed the same thing, and apparently some designers have said that adding stub wings was one modification they wish they had incorporated in their original designs.

I like the entire project, but really think Air Foiled shaped tanks are a GREAT idea Miranda!

Look forward to watching the build thread... hint... hint...

Thank you for sharing

 

[Miranda]

I like the entire project, but really think Air Foiled shaped tanks are a GREAT idea Miranda!

Look forward to watching the build thread... hint... hint...

Thank you for sharing

Hi John,

Thanks for your enthusiasm. I am working out the specs on stub wings now and am looking at airfoils that have good low-speed (relatively speaking) characteristics, such as the USA35B (used in the J-3 Cub, among others) and Clark YM-15. Both have nice thick cross sections give good lift and stall characteristics, as well as space for containing fuel tanks or light cargo.

I am going to try to make the stub wings each about 5 feet long with a 3 to 3-1/3 foot chord. They will have fixed inboard sections of about 18 inches, and a hinged outer section of about 3-1/2 feet that will fold upward for transport. The stub wings will be straight, unlike some of the old Pitcairn and Cierva autogyros that had upward angled wingtips to assist in turns (because they didn't have controllable rotor heads at the time). The inboard sections will house internal fuel tanks. The outboard sections could be used for very light cargo storage perhaps.

I will definitely post my progress once I actually start the build. For the next 4 months or so, though, I will mostly be working out the details - hopefully with input from members here.

 

[Timchick]

Have you considered a Yamaha 150 hp 4 cylinder engine?

 

[Miranda]

Have you considered a Yamaha 150 hp 4 cylinder engine?

No, Tim. I don't know anything about them. Where can I find more information, i.e. specs, performance, sourcing? My 3 major concerns are minimum horsepower (which this engine seems to have well in hand), maximum weight, and affordability.

At roughly $25k new the Rotax models are about 3 times as much as I can afford. The Subarus are affordable but weigh in at 220 lbs - about 50 pounds too heavy. The VWs provide around 80 hp - which is too little unless stub wings will make a difference. The stub wing solution may make the better of the VW designs workable, but I am not so set on a VW that I will ignore other designs out there that if they are a better fit.

Do you have experience with the Yamahas?

 

[BigBen]

Have you looked at the new Viking engine?
it has the horsepower needed and is just a little heavier than the 912 but at about 1/2 the cost or less. Liquid cooling makes for less cooling drag and the much larger prop than a direct drive VW or Subaru will give a lot more usable thrust.

 

[All_In]

Hi John,

Thanks for your enthusiasm. I am working out the specs on stub wings now and am looking at airfoils that have good low-speed (relatively speaking) characteristics, such as the USA35B (used in the J-3 Cub, among others) and Clark YM-15. Both have nice thick cross sections give good lift and stall characteristics, as well as space for containing fuel tanks or light cargo.

I am going to try to make the stub wings each about 5 feet long with a 3 to 3-1/3 foot chord. They will have fixed inboard sections of about 18 inches, and a hinged outer section of about 3-1/2 feet that will fold upward for transport. The stub wings will be straight, unlike some of the old Pitcairn and Cierva autogyros that had upward angled wingtips to assist in turns (because they didn't have controllable rotor heads at the time). The inboard sections will house internal fuel tanks. The outboard sections could be used for very light cargo storage perhaps.

I will definitely post my progress once I actually start the build. For the next 4 months or so, though, I will mostly be working out the details - hopefully with input from members here.

IMHO! That is an excellent plan!!!
These things take awhile, I KNOW, so I'll wait! Thanks for joining us and sharing!

 

[All_In]

No, Tim. I don't know anything about them. Where can I find more information, i.e. specs, performance, sourcing? My 3 major concerns are minimum horsepower (which this engine seems to have well in hand), maximum weight, and affordability.

At roughly $25k new the Rotax models are about 3 times as much as I can afford. The Subarus are affordable but weigh in at 220 lbs - about 50 pounds too heavy. The VWs provide around 80 hp - which is too little unless stub wings will make a difference. The stub wing solution may make the better of the VW designs workable, but I am not so set on a VW that I will ignore other designs out there that if they are a better fit.

Do you have experience with the Yamahas?

Both the Vicking and Yamaha's are cheaper and proving to be reliable since Todd AKS Racer 1st brought them on the market a few years ago now.

Todd and Greg Mills both offer Yamahas today.

If your frame can take the HP then I'd also consider buying a less that 70% used Lycoming certified aircraft engine as much of the east coast fleet is starting to be grounded for Intergranular corrosion of the main wing spars.
We've bought entire aircraft for less than the engine is worth and sold the rest to the bone yard where these engines can cost less than 3K to 4K with 75% of the time left with log books! For IO540's look up the list price.

 

[Miranda]

If your frame can take the HP then I'd also consider buying a less that 70% used Lycoming certified aircraft engine as much of the east coast fleet is starting to be grounded for Intergranular corrosion of the main wing spars.

I thought I read something about TSOd parts having to meet all ADs and other requirements even when used in applications that don't necessarily require TSO type material. I plan on doing all of my engine work myself, and my gyro will probably fall under the E-AB category and fly under LSA rules. As an E-AB aircraft I am not required to use a certified engine, but if I DO put in an engine from a certified aircraft, do I have to maintain the engine in accordance with the same requirements as if my gyro were certified?

I will look into these other engines, but they might have more HP than I am comfortable putting on my airframe. I know that just because I have the HP available doesn't mean I have to use it. However, it seems as though having too much extra ponies under the cowling might make it easier to inadvertently over-torque the airframe with too rapid an application of power. I suppose an engine could somehow be mechanically de-rated to avoid this possibility. In the Hughes 269s I trained on there was a mechanical governor we called "George" that automatically bumped down the rpm in case we rolled in too much throttle.

Any thoughts on this?

 

[CLS447]

Miranda is back !!!!!! Good luck building a Little Wing !

How did the firearms venture go ?

 

[JRB549]

IMO, go with the Yamaha for your powerplant. Got a proven record & part's are easy to get. Too many good things to say from those who have used 'em. Vicking need's longer haul to show it's stuff true.

 

[Miranda]

Miranda is back !!!!!! Good luck building a Little Wing !

How did the firearms venture go ?

Hi Chris,

The venture went very well after we worked through some rough spots. Nothing ever works as planned, and our startup company was no exception. Once we gained our momentum, became profitable, and paid off our debts I sold my interest and returned to Ohio to finish preparing our home for sale. I have to wait out the balance of a 2-year non-compete clause before I can re-enter the firearms market with new designs of my own. In the meantime I am finishing my house, working through a frame-off restoration/modification of my 1981 Chevy pickup, and building the gyro that I always wanted.

Thanks for asking,

Miranda

 

[Roundwing]

If your frame can take the HP then I'd also consider buying a less that 70% used Lycoming certified aircraft engine as much of the east coast fleet is starting to be grounded for Intergranular corrosion of the main wing spars.
We've bought entire aircraft for less than the engine is worth and sold the rest to the bone yard where these engines can cost less than 3K to 4K with 75% of the time left with log books! For IO540's look up the list price.

I thought that intergranular corrosion was caused by improper heat treating.
The corrosion starts from the inside out.
Why would east coast airplanes be more prone to it?
Any particular airframes more susceptible to the problem?
Just curious.

Rick

 

[bosca]

I too am building a little wing with stub winglets which will hold fuel therby keeping the danger outside the cabin. My airframe is a superpup single seat and is already completed. The fuel tans are 27 litres each made of aluimium. I have not as yet confirmed my engine choice however I am favouring an O-200.
Cheers,
Kym.

 

[All_In]

I thought that intergranular corrosion was caused by improper heat treating.
The corrosion starts from the inside out.
Why would east coast airplanes be more prone to it?
Any particular airframes more susceptible to the problem?
Just curious.

Rick

Hi Rick

I'm certainly not a metallurgist. However, I did research this years ago, the names always seem backwards to me galvanic corrosion I believe is name for the one caused by heat treatment or welding.
IIRC: Intergrunular corrosion occurs with alloyed metals, also known as grain boundary depletions. This occurs when the corrosive alloys are used to create special characteristics in metals what otherwise are noncorrosive like aluminum.

Some of these alloys can be attacked by the elements/corrosion. This makes the metal brittle because it has corroded microscopic veins running through the metal like a spiderweb or gold/quarts veins in rocks.

IA's are grounding the old fleet models when the intergrunular corrosion reaches where the wing spar attaches to the fuselage spar-box.
Only seen planes grounded, so far, that lived on East Cost their entire lives.

I believe this is correct but haven't looked it up in over 10 years at least if not correct one of the pro's will provide the actual answer.:noidea:

 

[All_In]

I too am building a little wing with stub winglets which will hold fuel therby keeping the danger outside the cabin. My airframe is a superpup single seat and is already completed. The fuel tans are 27 litres each made of aluimium. I have not as yet confirmed my engine choice however I am favouring an O-200.
Cheers,
Kym.

I'd love to see pictures Kym!!!

 

[Miranda]

I too am building a little wing with stub winglets which will hold fuel therby keeping the danger outside the cabin. My airframe is a superpup single seat and is already completed. The fuel tans are 27 litres each made of aluimium. I have not as yet confirmed my engine choice however I am favouring an O-200.
Cheers,
Kym.

That is excellent, Kym. Sounds like you are much farther along the development curve. Have you determined the length, chord, and airfoil you will use for your stub wings?

Thanks for joining in,

Miranda

 

[CLS447]

Frame off restore huh ? I have a 1982 GMC pickup I am trying to sell for $800. Last guy came to buy it & I couldn't get it started. Kind of ruined the sale !

Been too cold to do anything with right now !