mrbigg

My Feedback: (21)

looks nice. everyone needs an lt40.

cubflyman

Hi; I have several 46LA's and one 40 LA and have used them on several planes. our local club here in New Hampshire has great sucess with the LT40 with 40LAs. Try going down on pitch, you should be able to get 11k RPM with either an 11x4 or 11x5 prop. the lower pitch props will give you better acceleration to take off speed with a shorter roll and a better clime angle , like downshifting your car to go up a hill, and yet take the plane through any manovers with ease. why use a prop that wants to go 100mph on a plane that tops out at 60mph? with a 4 or 5 inch pitch you will set your idle rpm around 3000 RPM, and still land yet have better throttle responce if you have to go around again, fuel consumpsion won't be much more, if any either, with level flight at a little more than half throttle. APC props work well, but paint the tips white or yellow so that you can see where the tips of the spinning blades are. the gray props are invisable and almost as sharp as spinning steak knifes. Have fun and fly safe . TomP.

PS my 46LAs like a second head gasket and a tower plug or an OS #3 plug to run smoothly. It's snowing get out the skis!!

Hughes500E

My Feedback: (16)

I built an LT-40 for my wife and kids as well. We flew it with an OS-.46 LA
It flies great with that engine. The .40 should do alright but the proper prop will have to be found. Lots of castor
In the end though, I swapped it out for a ball bearing equipped engine. Much nicer taking off from the grass and quite a bit more power. Helped to get out of tricky spots, what a blast!
Have fun!

lownslo

Quote by Hughes500E. These were the exact reasons I suggested a ball bearing .46 in my earlier post. The grass field is a BIG factor. Our field is in it's 4the year and low powered .40 size planes, have a tough time getting airborne sometimes. I have flown from blacktop a little, and I am sure the .40 LA would be just fine there. If cost is no a big factor, you will be much happier in the long run with the BB .46. ....lownslo

fstevenj

The only comment I have is that I had to add significant weight to the nose of my LT40 with a LA40 installed. When I installed a TT .46 it balanced perfectly. The TT .46 was much more interesting to fly, but have since installed it on a 4*40 and put the LA40 back on the LT40. The plane does fly fine with the LA40 though.

Build-n-flyer-RCU

My Feedback: (4)

The bottom line- it seems everyone agrees:

A 40 LA will fly an LT-40 "trainer style" just fine but can make grass field take-offs a bit challenging.

A 46 FX/AX will make take-offs from grass a breeze and will power the plane through all the aerobatics that an LT-40 is capable of, while still maintaining the "feel" of a trainer.

A 60 or larger motor would turn it into a monster! Hmm, I have both an old LT-40 and a Saito 100 that I'm not using...

Your choice!

Hog Head

Well the more I think about it I want to use an OS 52 or a Saito 56. The four stroke just sounds better. I am also thinking about making it a tail-dragger and making the wing into a bolt on. Anyone know a good thread for these mods and possibly more that will still leave the plane a trainer as it was meant for? Thanks.

Build-n-flyer-RCU

My Feedback: (4)

Making an LT-40 into a tail-dragger or using a bolt-on wing mount won't change its "trainer" flight characteristics.

The tricky part of making the LT-40 a tail-dragger is setting up a steerable tail-wheel. Just about all sport planes have the rudder extended down to the bottom of the fuse and the tail wheel connects to the rudder for steering. Since the LT-40 rudder is above the stab you will have to install a second control wire from the rudder servo to drive it, or come up with some other sort of linkage.

Be careful when converting to a bolt on wing to make sure that the mounting points are solid! I saw a very nice Telemaster lose its wing on its maiden flight because the block that the wing bolts were attached to pulled loose from the fuse.

lownslo

Build-n-Flyer said: This is good advice. I also attached some photos of my LT-40 shown in Post #25 of this thread. The tail wheel situation on this design is a bummer. I have, in the past, run a control rod to a "home-made" tiller etc., but I got lazy on this plane and from the photo you can see a Sullivan Tail Wheel without the spring steering. I fly from grass and have put maximum rudder movement in to gather all the prop wash it can. I have had no problems with this system. I would rather have a steerable wheel...... but I get by with this just fine, and hardly notice the difference. In the pix of the wing bolt mount..... notice the small triangle stock under the kit's bracing plate. I also epoxied a small square of 1/4" ply under, and thin piece of ply over, the plate, and then drilled for my 1/4-20 nylon bolts. The front has holes for 2 dowels. (I am not sure if this is necessary.... but I wanted to stay away from the root ribs). MAKE SURE.... you
reach behind this former at the top, and epoxy a strip of ply doubler before drilling holes. I might also add to try to "bottom out" your wing dowels into the wing structure so they will NOT just be glued into the lead edge. Dab some epoxy on the ends to attach INSIDE the wing at their base. Note the .56 Satio..... this is a sweet powered, and sounding, trainer-style plane!! I really like taking this one up to relax after flying my other bigger stuff. I used it in my first fun-fly competition last year. This plane is very capable of doing a good job in a fun fly.... if the pilot was better! .... hope this helps......lownslo.

speedster 1919

My Feedback: (3)

That 40 La will be perfect for a trainer since you already have it. Just keep an eye on the plastic back plate sucking air. If you didn't already have that engine then a BB 40 or 46 would be better and wood go on a second plane. The longer this forum goes on ,some will have you up to a 90 size.

speedster 1919

My Feedback: (3)

I was close I see it hit 100 size. The earlier post is good, remember this is a trainer not pattern or 3d and 10x5 or 11x4 good to go. Even 10x4 will give more ground clearence.

lownslo

Speedster 1919 said: That may be true. My .56 Saito "was an extra" and was laying around like his .40 LA. I explained in earlier post about the same thing you just suggested, but I do prefer the .56 Saito for power and sound. I would not suggest to go out and buy an expensive 4 stroke. I WOULD go with a BB .46 IF you plan to stay in this hobby. You WILL use it again, and it will be good in ANY .40 size plane you should pick. ....lownslo

mrbigg

My Feedback: (21)

yeah i'm thinking of retiring my triplane "lola". i'm probaly going to pull the .61 s.t. out of the lt40. then i'll take the o.s. 1.60fx out of "lola" and put it in the lt. should pull it around with some authority.

Test005

I've planned to build a LT40 to use as relaxing cruiser, not trainer since I already know how to fly (well, sort of ...
When I get around to it I'll get an OS.52fs and also convert to taildrager.

(Ever heard the RCU slogan "Everybody should have a LT-40" ?? )

Hog Head

Hey guys , thanks for all the help. I am thinking of the .52/.56 four stroke because I used a .70fl in my GP Cessna 182 and I love the sound of it. Using the LA would be more economical seeing how I already have it but the FS sound is so sweet. After seeing a couple of posts of the LT converted into a tail-dragger, it seems like the thing to do and it will keep it unique at my club as it seems as there are more arfs than kits, especially with the younger crowd. As far as staying in the hobby, this will be my seventh plane and I have an SSE and 4*60 waiting to be built. I think I am hooked and here to stay. Thanks again.

mrbigg

My Feedback: (21)

that size four stroke would work. maybe a .72 if not that much more cash. on my taildragger i don't have a steerable tailwheel. a while back FLY R/C did a review on the world models Mach II. i think that is what is was called. well anyway, it had a rudder, elevator setup close to that of the lt. i was going to do a little modifying and make it steerable. not really necessary though. just a pain on windy days.