Hello,

Thanks to all the great responses here and the wealth of information I found in older threads, I have chosen the Sig LT-40 ARF as my trainer. It has been ordered and is currently enroute along with a TT Pro .46 to power her with. This airplane/engine combo seemd like the consensus pick as the most solid combo. While I read good things about the OS .46 AX as well, I decided on the TT as most agreed that it was as solid of a runner and cost 30 dollars less.

However, after ordering I ran into an opinion that the Kadet makes for a better trainer with an OS .40 LA powering it as the OS engine is easier to tune and the .40 size is a more appropriate power source for a new flyer. Moreso, I read that a used engine may be better as it has already been broken in and tuned, while a .46 was overpowering the Kadet and eroded some of the Kadet's signature flying attributes.

So with that said, I found a .40 LA for 40 bucks, and the owner claims that it has only had a gallon put through it. Should I go for this instead and save the TT Pro, that I spent 95 on, for my second plane? I am planning on getting a Sig 4* kit to build over the winter.

What do you guys think? Just roll with the TT Pro 46 I have coming with the Kadet or buy the OS 40 LA? This will be my first flying experience, so please keep that in mind.

Thanks!!

P.S. I ordered Hitec HS-325BB servos for the Kadet. http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDEL9 I believe these are solid servos and will do the trick. Would like a thumbs up from ya'll though before I install them.

60 size Saito, it's what I am doing next. I have one with a 46 la, it flies, but the slightest breeze blows it away. A strong running 45 / 46 will cover it, but I am to the point where I am tired of the 2 strokes. I have several of each, and the little bit of extra money outlay for purchase, doesn't compare to the way they run, use less fuel, and a lot less slime on the plane. They don't sound annoying, the engine makes a completely different sound that doesn't remind me of cutting wood. As far as maintenance, I have only had to adjust the valves on one engine in 3 years, and that took a total of 10 minutes. The LT 40 is a great airframe, although I have to say that I have put a lot more time on the Alpha airframe, because of the Magnum 4 stroke on it. It gives right about 20 min. flight time, and just keeps running without any fussing on 10 and 15% fuel.

I think the .40 LA might be a little weak. I have a Magnum .52 in mine and love it.

I hear ya Bingo. I have also grown tired of 2 strokes. When my son and I built his Kadet we used a 56 Saito and it is one sweet flying plane.

Go with the 46

I had an OS46AX in mine back in the day and it was perfect.

And once you are done with your trainer you will need a better engine for your next plane.

I go with the OS .46AX

What kind of fuel will you be using? Plain bearing engines like the .40 LA run best and produce more power when using glow fuel with large amounts of castor oil as part of the lubrication. If your local hobby store only stocks glow fuel with synthetic oil for lubrication, the Pro .46 will likely run better for you and provide simple, reliable operation.

Which engine balances the plane best? There is a difference of almost a quarter of a pound in weight between the .40 LA and the Pro .46 engines. It is likely that one of them, when test mounted on the plane, will balance your LT-40 on the recommended Center of Gravity (CG) better than the other. Starting out with an engine of the right weight will make it easier to trim and balance your plane.

The Kadet LT-40 is a terrific trainer and sport plane. Both the O.S. Max .40 LA and the Thunder Tiger Pro .46 are high quality and reliable engines. The .46 Pro will provide more power and it's extra weight will provide a bit of extra stability on windy days, but it will use fuel faster and increase the wing loading of the plane thus causing faster landings. The .40 LA will provide lighter wing loading and ensure smooth, gentle glide characteristics while training with the LT-40 and also sip fuel more slowly. It may lack the power to help you "punch out of trouble" if a landing approach goes badly, however.

Both engines are a terrific match for the Kadet LT-40, you can't really make a wrong choice, but there are a number of things to consider. If you want a light, gentle, "floaty" trainer and you can get castor oil fuel, then go with the .40 LA. If you want a faster, sporty trainer then use the Thunder Tiger Pro .46.

Good luck and have fun!

I'd use the Thunder Tiger .46 that you already have. I have a few .46LA's and I like them a lot, but I would not pay $40 for a used .40LA. I think you'll appreciate the extra power (the TT.46 will not be overpowering the plane), and you will have very little use for the .40LA on future planes.

Good luck

I have a Hobbico SuperStar RTF and it came with a .40LA. And the field I fly at is about 4,200 ft. above sea level and the .40LA pulled it through the air but it would hardly get in the air.Climbouts were very scarry. Go with the .46.

the 40 LA is not a bearing engine...it uses a bushing instead.....sounds like someone threw a bucket of bolts in an engine it will do ok as your engine if you choose it to power the Kadet with it....it is the combo I learned on....you will like the 46 on the Kadet...my daughter learned with that combo when she was 9.....either will work well for you

You can always slow down a .46, but you can only speed up a .40 so far. I've used both on that airplane, and I recommend a .46.

Regards
Michael

40 la would fly it but you won't be happy with it. The kadet will take a anything you throw at it. I've seen a guy put a saito 1.5. He reinforced the heck out of it of course, he was towing 1/3 and 1/2 scale glider with it.

I put an OS 91 on mine, took all the dihedral out with floats and was allot of fun, sold it awhile ago and is still flying. As a trainer it will do just fine with the tt 46

Having some extra power on tap is always handy when you are just starting out. Among other things, it lets you abort a bad landing and pull out quickly if necessary. Just because you have the extra speed and power available, doesn't mean you have to use it all the time.

The TT Pro 46 will balance the Kadet better than the 40. With the 46 you wont need as much nose weight to bring it into balance. That's what we put on my g/f's Kadet. Now believe it or not, I put a TT Gp 42 on a Kadet Senior that I built, and it flew fine. I had to add more weight to get it to balance, but it flew OK. Now I would rather have had more engine. I learned on that combo, it could fly real slow. I still have it and it's flyable. Both engines you describe are good engines. The extra power will really make a difference though. One thing I noticed with my TT Gp 42 was that I had to be sure I was getting full power in order to take off from the grass field I fly at. Once in the air I could throttle back and just cruise around very nicely. If you have a TT Pro 46, use it on the Kadet, it's good engine.

I'd be shocked if anyone could tell significant differences in landings and glide characteristics between those two engines. You will notice a significant difference in horsepower though, and on those occasions when you miss a landing approach or get too slow in the wind you'll appreciate that difference. Not to mention the TT .46 will be adequate for your first .40 sized sport or scale plane too.

I'm VP of Membership for a fairly good size club. At my club we use a LT40 and Kadet Senior every Tuesday on training nights and both have old, beat, OS Max 40 size engines. They are fine for learning to fly and are plenty capable at taking off and flying . They are extremely reliable at starting and not quiting unless run out of fuel. On the other hand the most popular choice for new members flying the LT40 is the OS Max 46AX. Based on your choices, I would save the money and go with the 40 size engine. The 46AX is more powerful, no doubt, but for training it REALLY isn't necessary and is more prone to quitting and deadsticking in my experience. I've heard countless times about an AX deadsticking, and mine did as well until really broken in. Don't know about the TT but I'd still recommend saving the money and going with the weaker engine to train with. Weaker is just a relative term. The 40 is more than capable at training, again, from experience. Once you have had the plane for a while and get into a new plane, you'll always be able to go back to the trainer and upgrade the engine to a larger four stroke RATHER than a 46 two stroke and will enjoy your trainer in a new way with more experience. Just my two cents, again, from seeing MANY other members personal experiences who have done just that.

Bite the bullit and go with a four stroke. Youll be glad you did.

That is definitely sweet. But I think a lot of guys flying a Kadet LT-40 are thinking of a motor that will give good service and is economical. But I do like the idea. What size and make is that? The Kadet needs nose weight anyway.

The LT 40 pretty well says it. I have an OS 40 in mine and it flies fine

Hello; I learned the most from a Kadet with an old Saito 45. I know that no one would recommend that combination nowadays, but if I had one today, I'd fly it a lot. I have had success with OS'FP range but not the LA's. I have a pair of TT 46's that have never failed me, more power then you'll need though. A new fellow is flying at our field, he tried an RV4, soon crashed it, he tried a Decathlon, but crashed it. Someone offered him an ARF Kadet cheap with a Saito 65,m which he bought and now flies all the time. He loves th agility and the low speed ability of the big Saito. We have tamed him down a bit, so he'll stop crashing his planes, but he's having a great time with it, and learining how to fly properly.

The Magnum .52 is a rock solid engine. I get 25 minutes of flight time on the standard tank so, in the long run, its cheaper. I actually had to add 1 1/4oz of weight to the rear but that was because of the landing gear I installed. I would highly recommend beafing up the landing gear. No more nicked props and mo more bouncy bouncy. lol

Thank you all for your time and responses. I will just stick with the TT Pro 46 as I already have it, and it is the consensus pick thus far.

So, what type of nitro would you recommend for the TT Pro 46/Kadet LT 40 combo?

10 or 15 % should do it. Up until now, I have used 10% on everything I own, 2 stroke and 4 stroke. Magnum, Saito, SuperTigre, Evolution, and OS. 10% is marginally less expensive than 15%.

Thanks, any particular brand that is commonly available at the LHS?

I use [link=http://www.morganfuel.com/cp_main.htm]Cool Power[/link] 15% synthetic and it should be available at most LHS. Some people will tell you to use a fuel with Castor but I like the fuels without it.