I'm a newbie, just about to get my first plane. I was completely ready to get the Thunder Tiger .46 BB for use in my Tower Trainer. However, my friend saw te specs online at Tower Hobbies and he said that having the needle valve up front near the prop an be really dangerous. He suggested the .40 LA for use in the trainer. I'm looking for an engine that I can hopefully take out of the trainer and into my 2nd plane when the time comes. I've read that bushing engines aren't as good as BB engines. Is this true? Also, I read that hte magnum .46 ABC is also a very good engine, and the needle valve is in the back so I won't have any missing body parts. Is this a good choice? Mainly I'm looking for a user-friendly, relatively inexpensive (I'm hesitant on buying the $120 OS AX), and reusable engine that will give me enough power to handle the 2nd plane. Any help? (By the way I did a search on engines, and nothing seemed to address the remote needle valve issue)

Thanks.

The needle valve on the TT 46 is angled backwards so there should not be any problem with getting aknuckle in the prop.

Either the TT 46 or the Magnum XLS 46 would be excellent choices for long term use. The Evolution 46NT has been satisfying for most people also.

The OS LA series has it's place in modeling society but the new comer rapidly wants more power in a different model. It's cheaper to just start out with a higher performance engine from the start. You don't have to run it wide open throttle. You can fly around at half power if you want to. The LA engines seemed to be more satisfying to an experienced modeler who knows what they are and are not. He uses them on an appropiate plane for their power.

Enjoy,

Jim

Hey Deathreborn I also was concerned about the needle valve in the front. I got a Magnom46 with remote needle and have been very happy with it. It has plenty of power plus Iam also going to put it on my second plane. Its on a spad Debonair right now, if you are as new to this as Iam the spad may be the way you want to start. I built this thing in a few hours, it is with out a doubt the toughfest, thing I have flown. I am still learning to fly also and to say I have landed hard a few times is a understatement. I have nosed this plane in many times from lack of ability it bends and is flyable again. If you have the chance check out Spadtothebone.com great place and great guys that will help if they can. If I can help give me a shout at [email protected] take it easy and remember this is supposed to be fun. Thanks mekanic

X:

Don't believe all the hype about a remote needle. You can stick your fingers in the prop just as easily with either location, and the remote is more particular about slight air leaks.

All this makes the Magnum engines a good choice, as the needle can be installed up front or in a remote mounting. Your choice. This is in addition to the Magnums being just plain good engines.

I have all mine in the front mounting when possible, to me the advantages outweigh any supposed advantages of remote assembly.

Bill.

I think remote is nice to have, but mainly I agree with Mr Robison; you're only looking at another inch and a half or so, and although every litte bit helps, it's more important to learn to be EXTREMELY careful around the prop, never take anything for granted, move all extraneous equipment out of the way, and never, ever take your eyes off the needle valve while you are adjusting it with the engine running. Ditto the opinion regarding Magnum engines, although there are others as suitable; OS 46 AX is a good one, and you could consider a 4-stroke; a Saito .56 is more than equivalent to a .40 2-stroke, a .40 Saito would also work.

I am siding with Bill on this one my ASP91 2S came with both front and rear needle options less chance of leaks with the front mount
so on the front it went as far as a safety issue most injuries occur reaching OVER the prop from the front not adjusting the needle I have
had the prop *brush* a knuckle while adjusting but was never cut I have seen guys reach over the top to adjust the needle very
foolish

OK, thanks for your advice, I'll go with the magnum then. I think I'll try the rear setting for a bit, just to get used to handling the engine, then move it up front to avoid air leakings.

Just a quick question (Sorry, I know it's a bit off-topic, but I don't want to start a new thread and clutter up the forums): The spec page on tower said the engine needs a 10x5 prop for break in. I know I'm a newbie, and this is probably obvious to most, but: what would be the normal useage prop then? I'm not too sure what would be normal for a .46, all the charts say for .40 only. Thanks in advance, sorry to go a bit off-topic.

http://www2.towerhobbies.com/cgi-bin...2&I=LXBUX6&P=K there's the main spec page, that's the magnum .46 ABC.

X:

The 10x6 or equivalent load is the "Normal" prop for the average 0.46, but many, including the XLS 46 Magnum will run fine with a 10x8 equivalent load.

Don't be scared by the term "Equivalent Load," that just means if you need a larger diameter you decrease the pitch, or a smaller diameter increase the pitch.

On one of my twins, with a pair of Mag 46 engines I'm running 10x6 three blade props, my Modeltech "Magic," with a 46 FX has a 12.25x3.75 APC. A 12x4 would be about the same load. Or a 9x8 prop.

Generally, on a sport plane, start with a 10x6 and see how it goes, adjust from there.

Bill.

Hi!
Don't start with a 10x6 prop at least if you fly at sea-level...it is too small prop for all highwinged trainers using a .45-.46 engine.
The propeller you should use is a 11x6 APC ...both for running in and flying...no special running in prop is ever needed on modern engines.
As for a ball bearinged engines like the Magnum and TT compared to the OS LA plain bearing engines; I personally think the OS is the best engine for a newbie flying his/her higwinged trainer.
The reason for this is the OS LA:s lightweight and mild behavior. Light weight is of utmost importance in every airplane. Every gram counts! That you don't think of when you are a beginner.
Having a too powerful engine could also be hard to a beginner.....People often say" I can always throttle down" ...that is true...but what they don't think of is that power comes in different portions.....with the OS .40-.46 (or TT.42) it comes in a gentle and smooth way when you give full throttle....when you give full throttle to a ball bearinged engine the power response is more aggressive.......both engines will naturally respond instantly ....but with a ball bearinged engine the power increase will sometimes be too much.....at least for a beginner... making the airplane go all over the place and perhaps crashing just because the pilot did not have enough experience to cope with the shift in trim that occurred because of to much power when he gave full throttle.

I would strongly recommend a plain bearing engine like the TT .42 and OS LA .40 and .46 before a ballbearinged engine.
Your airplane will fly slower due to the lighter weight, The power increase when you give full power will come in a gent-lier way, less fuel is used, The engine will hold up for as many years as any ballbearing engine, No ballbearings that get rusty and could brake.
Perfect engine for a twin due to it's light weight and reliable behavior. Could stand a crash better due to smaller carb and no dirt in the ballbearings and cheaper to rebuild.
The only minus is it slightly lesser power output compared to a ball bearinged engine.


Regards!
Jan K
Sweden