Hi

So I am looking to buy a Hangar 9 Alpha trainer DSM2. Last summer I had a (very) old alpha trainer given to me by an uncle who had gotten out of the hobby. I had made several posts about it on here from time to time. I managed to teach myself to fly it, building on previous experience from a Parkzone ember. Eventually it crashed when (i think) the receiver battery died in flight. Anyway, I plan to buy a new one to fly this summer but have a few more questions.

First off, the hangar 9 site says it requires a glow plug to get it ready to fly. I can't believe it doesn't include a glow plug when it has almost everything else. Also it says the evolution engine has been run in at the factory, which would have required a glow plug to be installed. I have a bunch of equipment (glow heater, starter, fuel, etc) left over from last summer, but Im not sure I have any glow plugs. Exactly what type/model/brand of glow plug will work in this plane?

Second, I know the plane will fly about 10 minutes on a tank of gas. But how long before you have to worry about the receiver battery? Last summer I was paranoid and would only do 1 or 2 flights before recharging the receiver battery, and still lost the plane because of this issue. I knew I should have replaced that ancient Nicad battery. If I get a volt meter to check voltage before each flight, what should the voltage be? How many flights can I expect before needing to recharge it? I really don't want to loose my new plane to this issue.

And one day I saw a rather scary video on youtube of an alpha trainer's wings folding up in flight, after pulling up too hard out of a dive. Is this common? I would think planes would be built strong enough that nothing you did with the sticks would cause it to break up in flight, unless you hit something.

Also, is the included DX5e radio really a full range radio? It says it runs on 4 double A alkalines! My parkzone ember transmitter runs on 4 AAs and only has a range of a few hundred feet. And this radio will work with a DSM2 parkzone sukhoi, correct? The main reason I want this plane over other 40 size trainers is because I have reserved a parkzone sukhoi which I will also need a DSM2 radio for, and I want to save money.

And if it seems odd that I am buying an advanced aerobatic sukhoi, and a trainer, its because I had an ember, which I had taken to its limits. There were 2 ways to go, either bigger and faster (alpha trainer) or more aerobatic (sukhoi). I decided to do both. If the sukhoi is anything like the ember, it won't take any damage when I crash it anyway.

Thanks for your help guys!

I'll take a shot at some of your questions. I don't have the new Alpha, but I have one from 2 years ago.

Regarding the wing, the instructions tell you to join the wing halves with a 1/2" strip of tape. While this may work if you use enough rubber bands, I epoxied mine together, as do most folks.

The engines are supposedly pre-broken-in, but I think they still need a couple of tanks run through them before flying. Mine came with a glow plug. I think any standard plug will work, either the H9 brand or an OS #8.

The RX battery is usually good for at least 4-5 flights. I use one of those loaded voltmeters with the LEDs on it, and I stop flying when it gets below 70%.

And the new DSM2 radio is a full range radio. The AA batteries do not affect the range, just the operating cost

Good luck

I bought a Hanger 9 Alpha Trainer ARF as a replacement for the club trainer that I accidentally smashed up. Short story is: well, after flying 2.4 GHz, I simply didn't notice that I forgot to raise the antenna.. [:@] But, stuff happens to us all.. a brief lapse of brain function.

Anyway, I put an OS 46 on mine. I have not yet maidened it yet, but that somes soon. On the ARF, of course, the wing halves get epoxied together. If the RTF version is similar to other RTF's, there is a steel rod that is the main spar and is used to support the center of the wings at the joiner. Many have a tab with a couple of screws that pull the two halves together and hold them there.

One suggestion might be to epoxy the steel rod plus the two halves together in one shot.. cover the spar with epoxy then the two halves then put the two together, center them (use long setting epoxy, at least 30 minute for this so you have time to work it) and center the halves so that they are straight, tape the halves in place, clamp them so that the halves don't separate or flex from gravity, and let the epoxy set up. That way the two halves will be permanantly joined, which is a good thing.

As far as the glow plug is concerned, well, I had an Evo engine, in fact three of them, and I believe they all came with glow plugs. Odd that it did not. However, you might go to Horizon Hobbies and take a look at the recommended plug and a comparison chart and pick up a couple of spares (you never know). You can use OS plugs as a direct replacement if they are readily available at your LHS. Just look at the comparison chart and pick the one that matches the recommended glow plug.

As far as the receiver battery is concerned, batter life depends on several factors, among them the capacity of that battery. Most radio systems come with 600 or 700 mah battery packs. For most four basic servo applications, this is more than adequate for about four flights or so, depending on the style of the flyer (lots of stick activity will quickly drain a battery pack).

Other factors include such things as linkage binding and end stops for the throttle. I keep preaching Voltwatch as an added item to planes. One nice thing about that is that it gives an immediate indication of such things as binding and incorrectly adjusted throttle linkge.. both of which really require immediate action to remove.. fix the binding problems with control surface binds and with end stops on the throttle (throttle servo tries to move the throttle further than it can go when it reaches the stops at both ends of the throttle, so the servo works much harder trying to move the throttle further than it can go.. results in severe current draw from the battery pack AND could damage the servo. A properly adjusted throttle linkage really is part of the initial setup and should be given careful consideration when assembling any aircraft, and even with RTF's, should be looked at. Even the factory makes mistakes.

I'll try to find a glow plug recommendation for you.

CGr.

Well, their manual for the EVO 46 engine calls for an EVO6P1 plug. I will try to find an OS replacement if you care to have that.

This is the RX battery voltmeter that I use. Like I said, i fly it until it says 70% and then quit. That may be conservative, but it's worked for me so far.

http://www.horizonhobby.com/Products...ProdID=EXRA502

The Voltwatch is a similar setup, but you mount it right to your plane and you can always tell how your battery is doing.

http://www3.towerhobbies.com/cgi-bin...?&I=LXHDJ2&P=0

One other thing - if you don't go with the Voltwatch, you should at least install a charge jack on the outside of your plane, so you do not have to remove the wing to check the battery.

AND, by all means, get in to the habit of checking the battery voltage, under load (meaning with everything turned on) before and after each flight. Get redundant with this. You never know, and it will always assure you that you are ok to fly. This is what makes the Voltwatch a handy device.

You may, most likely, will get two different readings with the engine running than with it not running. The reason for this is that the engine vibration will cause servo action even without input. Minor, but some action. So, the current draw, thus the voltage, will be slightly different with it running than with it not running.

CGr.

1) any standard, long, medium heat, plug will work.

2) the battery is considered dead when it reaches the stated voltage, in your case 4.8 volts, never go lower than 4.6V

3) As with any trainer this is a high lift flat bottom wing, meaning they are not meant for high G high speed aerobatics, it can take allot but high speed high g-s are going to fold the wing on any trainer.

4) I don't know much about the 2.4ghz stuff

Since the Op is going to buy a new plane, I will throw my 2 cents in on the third thing you said. Not all trainers are flat wing and not all wings are joined the same way. I folded the wing on a slightly used Avistar with stock .40 la engine because the wing had been joined improperly by who ever built it. I have 2 other Avistars that I bought new and put together myself, one has a Magnum .46 and it will take any amount of G's or high speed aerobatics you can put it thru. I use about 14 rubber bands and I have pulled some full throttle loops where I could see the wing seperate slightly from the fusalage during the pull out. If the Op is looking for a trainer that will perform aerobatics like a sport plane, he might want to re-think the Alpha 40 and get an Avistar.

Thanks for all the help guys. I really like that voltwatch onboard battery monitor thing. Most transmitters have battery indicators. Every plane should probably have one of those. However, on the tower hobbies page for the voltwatch (the one mclina linked to) it says that for radios other than Futaba, you have to modify the plug. How do I modify the plug to work with the Alpha's spektrum radio?

Also, someone mentioned installing a remote charge jack, so that I dont have to remove the wing to charge the battery. This also sounds like a good idea. What would types of wires and stuff would I need to buy to make a remote charge port? And is it ok to leave the wing on all the time or is it not good to store the rubber bands under strain like that?

Oh and mclina mentioned that although the engine is advertised as broken in and tuned at the factory, that I should still run a few tanks through it before flying. What I don't understand about breaking in engines is why can't you just break them in while flying, eg, break it in in the air? I guess my last plane was given to me, and had already been broken in years ago, so I didn't have to worry about this.

Thanks again guys!

The charge jack is just a piece of plastic, into which you will insert the charge lead that is attached to your switch. A lot of times they come with the radio, but if not, here is one:

http://www.horizonhobby.com/Products...?ProdID=ERN147

You generally need to remove the wing to transport the plane, unless you have a really large car or fly at your house. The rubber bands will not only degrade from being permanently stretched, but the fuel will degrade them as well. I usually buy a bulk pack of rubber bands at Staples and use a fresh set every time I fly.

http://www.staples.com/office/suppli...3579:SS1037866

If you do have to modify the plug on the Voltwatch, it is just a matter of clipping off a tab on the side. Some Futaba servo plugs have a small plastic tab molded into the plug. You can just sand it off or slice it off with a knife.

And you do continue your breakin process in the air, running the engine rich and slowly leaning it out. I run them on the ground until I get a good reliable idle, and then fly them. Just don't go too lean too fast.

Good luck

Futaba servos have a tab on the plug. The voltwatch does not. This does not matter a bit. As long as you observe and follow polarity of the wires (red to red, black to black) you're ok. Just plug it into a vacant channel on your receiver. If you do not have a vacant channel (four channel and all four are used), then simply get a Y cable, plug the one sided edge into the receiver and the Y part, plug the servo in one and the voltwatch in the other and you're all set to go.

FYI, the signal wire on the servos can be different colors.. blue, white, yellow, orange.. doesn't matter because that wire is not used with the voltwatch. Only the + (usually red) and - (usually black). On some, it may be brown.. I think Spektrum servos are brown rather than black, but I might be wrong. The main point is that the + (Red) goes to + and - (black) goes to - .


CGr.

What CGr. said, plus note that the red wire is in the middle of the three, so if you do plug something in backwards, you just send signal to ground, but don't cause a short. So you won't break anything doing this. I've done it plenty of times with batteries, servos, you name it.

I've also trimmed a number of Futaba leads down to fit JR gear, it's easy like the guys said, but sometimes you have to trim not just the little tab but two of the corners off of the connector as well. Depends on the gear you have. Since it's JR/Specktrum, you'll probably have to cut off the corners.

As for pulling the wings off a plane, any plane can be torn up in the air if you either assemble it wrong, or if you over-speed it or give it enough control throw. Most trainers set up exactly the way the instructions say in every way will NOT come apart in the air just from a full-throttle-full-elevator pull without a terminal velocity dive first, and probably not even then. But if you increase the elevator throw or change anything on the setup, things change. Even changing the prop on an Alpha can dramatically change the max airspeed you can reach, and therefore dramatically increase the maximum load you can put on the airframe.

So, the safe thing to do is assume that you CAN destroy any airplane in the air with it's current setup, and avoid doing things like full-power dives into full-elevator loops and stuff like that.

The Evolution engines aren't really "broken in" so much as test-run. They will continue to break in a bit over the first few tanks of fuel, and the low end mixture might change a little as it does, but you can fly the engine right out of the box, I do.