I have a Greatplanes giant big stick( 13 pounds w/ engine ) with an os 91fx engine and I realize that it is considered underpowred but all I want to do is fly very straight & level. In your opinion will it fly ?

Thanks Varmit

With the right prop it may get off the ground and be alright for casual flying... but you will be missing out on a lot of the fun with sticks.

The GP Stick is great for flying in winds, but with your configuration I'd never risk it.

Consider purchasing a larger engine.

If you have enough ground speed to get it airborne it will fly but on the sluggish side. A plane weighing in at 13 lbs would qualify for a small gas engine a lot better than the 91 FX 2 stroke glow engine. Go any larger on a glow engine and you'll be going through more glow fuel than you ever wanted!

The "gas" engine below would pull your plane around with no problems much better.

http://www.horizonhobby.com/Products...ProdId=ZENE26A

The engine recomendations for that plane are....2-stroke 1.20-1.60 cu in (20-26 cc) or 4-stroke 1.20-1.80 cu in (20-30 cc) glow engine, or 25-35 cc gas engine

The 91 FX is on the extra extra low side.....good luck

but then the plane will weigh 15 pounds.and yes the stick will fly on the 91fx

It will fly it. Just be carefull not to power up and yank it back on take off. We all get in the habit of taking off that way. You need more of a scale takeoff.

david

I dunno? [X(] Definitely pushing the limits here.

Does the term 'wallow' mean anything? That's how that will fly with that engine. Way to much weight for that engine to pull around efficiently. It may fly, but not very well, and probably at full throttle all the time.

To fly a 13 pound airplane on a .91 engine will require a very experienced pilot.

How did the airplane get so heavy?

Bill

After thinking about it, I would not even install a G2300 on a 13lb plane. First choice on size would be around a 1.60

A 91 fx is going to pull 10 pounds of thrust. It isn't a 3d plane but it will sure fly. Nun of the trainers we learned on had a 1:1 thrust to weight ratio.

I'll be the first to admit a .91 on a 13 pound plane is a bit of a stretch. But then again, most models are tremendously overpowered these days....at least mine are. To put it in perspective, I remember back in the early 80's when I first got into this wonderful hobby, one of the real hotshot pilots in the club brought out a new bird. It was a .60-size Cosmic Wind. I have no idea who kitted this beast, but Mike did a beautiful job on it. At the time, .60-size planes were the upper limit for most folks in our club. Anyway, the CW weighed in at 12 pounds and was powered by a OS .61. Did he have problems with it? Nope. Could he take off and pull vertical straight out of sight? 'Course not. The point is, it flew and it flew well in a very realistic manner. I think a marginally powered plane (by today's standards, anyway) is an EXCELLENT way to learn the subtleties of flight. It requires a thorough knowledge of your plane's flight (especially STALL!) characteristics, and it demands that you plan ahead. You get behind the power curve and it's probably gonna need repairs real soon.

Just my thoughts.....

Erik

You will have to fly it on the wing, something most RC pilots don't know how to do, If you get into a bad situation, you won't have enough motor to pull you out of it, so keep that in mind as you fly. Keep it smooth and don't do anything wild and you should be okay. None of this Bank yank stuff and keeo your takeoffs long and smooth with gentle climbouts. All I can say is AIRSPEED,AIRSPEED,AIRSPEED and prop it properly.

I hope this works out but this has "doomed" written all over it.

How do you get a Stick to 13 pounds?

its a giant stick specs are weight 13-15 pounds

SPECS: Wingspan: 80.5" (2045mm)
Wing Area: 1520sq in (98sq dm)
Weight: 13 - 15lbs (5.9 - 6.8kg)
Wing Loading: 20 - 23 oz/sq ft (61 - 70g/sq dm)
Length: 74.5" (1892mm)

I missed the "giant" part, sorry.

Weight is only one issue, how about all that drag. GEEEEZ.

Dude, you need more motor.

It may get off the ground, however I got money says it don't come back to the ground in the same condition.

Do you have a 91 on it now because it is the only thing you have? Cannot afford another motor? Or you just wanna try it? Almost any reason you give will not help the fait of your bird.

Don't do it.

However if you try it, hope you have a long paved runway and make sure to get vid of it. Can't wait to see that stall on the first turn downwind.

It will fly,

I am a Scale Builder of Giant Warbirds and all my planes weigh more than there supposed to because I make them true to scale and this adds weight. Just fly it like the other Gentleman said, like a real airplane. Not everyone wants a rocket. Real normal planes don't go vertical or hover and I know this because my full scale Piper PA-28 140 will barely get off the ground on a hot day with a high Density Altitude and full fuel with three people inside. If I only fill it half way it will get off nicely. Don't use a huge fuel tank or at least don't fill it up and conserve weight.

JMHO,

Gibbs

I have the plane and I have the 91fx but I just don't have the $ 300 for a suitable motor .I just may hang it up for the time being and see if my wife will let me buy a fuji bt-32 with her egg money. ( lol yuck,yuck )
On the serious side; we have a 1200 foot paved north to south runway and the temptation is getting the better of me, but I sure would hate to crash this bird because I really like a plane that I can see.
I really appreciate the posting that you guys have done

Varmit

Excuse me? Do you have $150? SuperTiger will take care of you

Like he said!

A bigger 2 stroker is in your future if money is problematic.

At worst sell the .91 FX and you'll be able to purchase the larger Supertigre outright with the proceeds.

Just remember that the ST may need more TLC to get tuned up properly.

That said, deadsticks are trivial on your Stik.

I've NEVER worried when my engine has deadsticked ( usually after long blenders started from high altitudes, there's that uncovered clunk problem again! )... Even from a low altitude the GP stick floats in for a LONG time.

I fly with a guy every weekend who flys a giant big stick with a 1.6 O.S. and it rips. I fly a .60 size big stick with a .90 super tiger and it rips. I'd say yours would be a good bit under powered,but it would fly if you have the proper runway and dont expect many manuevers or quick recoveries. Might actually be nice for landing it,just dont throttle back to far.

Whats this suppose to mean? You agree that a oversized plane with an grossly underpowered engine is fine. Yet you will take three people up in your own plane on a High DA of a day and barely get off the ground with a half tank of fuel? Excuse me if I disagree with your logic here.

I don't believe any of us here are saying the plane won't fly, we're saying it won't fly very well. So why run the risk of stuffing it when it is all completely unavoidable.

That 91 will work fine if........you take the wing off and just run it up and down the runway practicing on keeping it straight on take-offs.

If you have a paved runway set some pilons up and time yourself on each lap. The other guys flying their planes can be your spotter.

OS claims 2.8 horsepower. Multiplying that by a 60% marketing B.S. factor gives you 1.68 horsepower or 1253 watts of power. The plane's weight divided into the power gives you a power loading of 96 watts per pound. It will fly like a trainer.
Your biggest problem will be balancing the plane with that small engine up front. I'm sure that that plane was designed to need the weight of a gasser up front to come to the proper CG location.

Its not the weight as much as overcoming the drag. I fly a 13lb plane with a 61 2s and it is not at all underpowered, it will take off in 150 ft. BUT this plane is slippery low drag and it will fly over 100mph. I wouldn't try a 13lb stick on a 91, because of the size and drag of the plane.