JIMARRINGTON

I am finishing up a 40 size Wing Mfg P-40b. Had originally planned to fly it with an OS 40 LA and a 10x6 prop. Put her on the scales last night and looks like it will end up at 5 lbs. dry. The engine is mounted upright. She is fiberglassed with PolyC.

Will this be enough motor for this plane? Any and All opinions would be appreciated.


Thanks
Jim

mcarleno

I don't think you'll be happy with an LA 40 in a 5 lb. bird. If you looking for 2S options there is always the OS .46 AX (a litte expensive in this size range). Tower sells the SuperTigre GS45 ABC for $64.99. This engine screams with lots of power but it is a little heavy. I have one in a 40 size mustang turning a trimmed MA 11x7 (10.5 x 7). She'll do close to 85 MPH --- very cool on that low high speed pass.

If you looking for a real screamer, the Tower .46 is the most powerful in its class. Its $79.99 but will turn an 10x7 at about 15,000 RPMs.

Another great buy and lots of torque is the SK50. I have one in my Yak-3 40 size. Even though its cheap, its one of my most reliable engines. This engine won't turn more than about 12,000 RPMs, but it will do about 11,200 with an 11x7 ($59.77 from astrcplanes.com).

Razorback58

My Feedback: (8)

Jim, for the money it's hard to beat a Thunder Tiger Pro 46. Good power for the money. I think that you would be much happier with that instead of the OS 40 LA. Not enough kahoonas there to do that P-40 justice!

JIMARRINGTON

fuse pics

JIMARRINGTON

Thanks for the responses. I barely had room to fit the the LA in there. Keep in mind that this is an extremely sport scale model.
Wing loading will be just under 22 oz/sq ft with 550 squares. Wing calls for this plane to take a 35-45. I already have a Tower 46 that I could use. Still think I should pull the LA and go with the Tower?

Thanks
Jim

strnglvr

My Feedback: (1)

How about you fly it, then see what you think of it then, looks to me like the engine's already in, be ashame if the la pull's it well,.....PDK.

mcarleno

First I agree with "strnglvr"


If you've got the Tower and your not happy with the LA, I would go with it . Great engine and LOTS of power. The LA from backplate to driver washer is 2.75" and the Tower is 3.25" So your going to need to find 1/2" in that skimpy engine compartment. The TT Pro is even longer than the Tower.

JIMARRINGTON

Thanks again guys. I will move on ahead with the LA and see how it goes.

Marc,
I have been watching your Red Star builds. Great looking planes.



Jim

kdc

I would always suggest running a new engine in an old favourite model before using it in a plane that is also untried.
I use an 11 x 7 Graupner on both an OS 40 FP and an ENYA 40SS plain bearing. They work well, so I suggest it for a 40 LA too

tigertooth

My Feedback: (1)

Nice looking P-40 Jim. I like the way you ended the canopy just behind the windows. I have built a couple, one with a Fox .40 BB. The engine was mounted upright and had just enough scale power but could have used more. Nice thing about it was you couldn't see the muffler as easy as it was the tilt down version. The second version was powered with an OS Max .40. Again, not over powered. I would go with the lightest .42 to .46 I could find and you will be happy with it. Built light, the P-40 will have a nice long glide when landing, Make sure you reinforce the landing gear blocks with 1/16" ply wood ribs or they will bust loose on a hard landing, don't ask me how I know! Good luck and have fun. Richard.

JIMARRINGTON

Thanks Richard,

Great advice from someone who has actually flown one of these. When you say keep it light, how light do you mean? Mine looks to be around 5 lbs. dry. I am not looking for a speed demon but scale loops would suit me. How underpowered would it be with the LA? Cant see how you could get much more motor on this thing, not much room left.

Jim

tigertooth

My Feedback: (1)

Hey Jim, There isn't alot of room for a larger engine and weight wise the LA and Fox .40 are almost the same. My first plane was really the best flier. I tried to keep the wing skin adhesive light ( Dave Brown), built up wing tips and cowl chin, monokote finish and DB wheels. Almost 4.7 lbs. and 5 lbs is still good with the nice finish you have on yours! Scale loops will be great. The next one I build will have a built up tail feathers and use 1/8" balsa instead of the 3/16" stuff. Send us some pictures of in flight and let me know how it flies. Thanks! Richard

JIMARRINGTON

Richard,

By making some modifications, it would be easy to shed some weight off this airplane. Built up tail feathers and built up fuse. I built it the way I did because I wanted to try out some new techniques. I have a TF Fw 190 Dora in the box for later. My main goals were to build a warbird model with a glass finish. Play around with a little detailing (I added some hatch covers made from aluminum duct tape). Try out airbrushing with craft paint and see how it holds up. And lastly, get a lot of practice flying a warbird this summer. I want this one to remain as gentle as possible as I gain experience flying a warbird.

As for reinforcing the lg blocks, its a little late for that as the wing has been glassed and is ready for paint. We fly off an asphalt runway though so hope they hold up for a while anyway. This is not my first warbird. I built a 46 size FW 190 A last year and am still flying it. It was a plans built model from some plans I got from AMA. She is a *****cat in the air but the takeoffs and landings with those long retracts is a little hairy. She won model of the year for 06 in our club. Will see if I can find a pic. Powered by a GMS 47 with a Bisson Pitts and so far I like her best with a K series 12 x 4 prop. Top speed is low but she jumps off the ground in a hurry and this prop seems to help slow her down best for landing.

Jim

JIMARRINGTON

I added a canopy and pilot after these pics were taken. Maiden flight ended with her on her back of course.

tigertooth

My Feedback: (1)

Sounds like you had alot of fun finishing the P-40. You will have no problems flying this and is pretty solid in the air. Richard

JIMARRINGTON

Yes Richard it was a lot fun building this one. Got to try out a lot of new things. Fiberglassing with Polycrylic. Worked really well. Airbrushing with craft acrylic paint thinned with Windex. Also worked really great. Need to find some better tape for masking though as the thinned paint goes on pretty wet and wicks under the tape a little. Finished the 3rd color on the wing last night so some decals, panel lines, clear coating, hook up the ailerons and strap on the wheels and she should be good to go. Maybe Sunday. Will post some finished pics.

Also, I am not real sure how accurate my scales were. I was using a cheap kitchen scale that only goes up to 5 lbs. When finished, I will weigh again with a better quality fish scale. I think she may be a little lighter than I was originally thinking. I hope anyway.

Jim

JIMARRINGTON

Couldn't resist. Just had to see what she looked like altogether

adam d

I agree with razorback I have 2 TT pro 46 and they have tones of power and are dirt cheep(high quality dirt the good growin kind) they seem to pull my 5-6lbs planes around easyly and grass takeoffs are a breezzzzzzzzzzzzzzzzz.

p.s jim the plane looks great!!

Adam

JIMARRINGTON

Finished up the wing last night. Then put it on the scales. Bought some new and I hope more accurate scales last night. Came in at 5 lb and 5 onces. With all equipment but with no fuel. I used an 8 once fuel tank.

Now I am a little worried. Will the LA 40 get her off the ground? Keep in mind that I want to keep her mild as my original objective when I started this model was to have a cheap and mild warbird that I could practice takeoffs and landings. I have a Tower 46 in another model that I could swap but really don't want to. Do you guys think it would even be worth my time to try the LA 40 first or just make the swap eventhough I dont want to?

Thanks
Jim

JIMARRINGTON

Well after getting her all assembled, she came up a little tail heavy so that made it easier to decide to go ahead with an engine swap. Last night, I pulled my Tower 46 out of another model and got it ready to go into the P-40 this afternoon. Since I had to add weight and she was already on the bubble for the 40, I might as well make good use of the weight I have to add. So my TT GP 42 went into my Sky walker II and the 46 is going into the P-40. She will also get a MAS 11x6 to go with it. I made the LG legs about a Half inch longer so should still have plenty of ground clearance. The tail wheel is also a little taller than called for so she sits pretty high. I will take some finished pics before trying to commit aviation just in case so that I can load them up here. If the wind cooperates, tommorrow will be the day. Forecast is for 10-15 out of the South which should put it right down the runway. A good wind should make takeoff and landing a little easier.

Jim

tigertooth

My Feedback: (1)

Thanks for the update Jim and may the first flight go smooth. Richard

P-40 DRIVER

I had one of those, glassed with an Enya 40 in it. Kinda heavy but it flew well. A 40LA should fly it, you may not be able to bore holes in the sky but it will fly it. RC airplanes are so over powered these days that most guy's forgot what the wings are for.

JIMARRINGTON

Took her out to the field today but didn't put her in the air. With 15-20 mph slight crosswind and an inner ear infection I just didn't have the feel for it today. Final AUW dry after changing engines and adding 6 onces lead in the nose was 5 lb 12 onces. Still not bad considering all the extra detailing I did. Here are some finished pics I took before swapping out the engines. If you look close you might just be able to make out the panel lines. Hope to get another shot at it next week. She turned out so pretty that I want to have the best chance of success as I can.

Jim

JIMARRINGTON

Forgot the pics.[X(]

tigertooth

My Feedback: (1)

Nice job on the P-40!