3D BH Design 50% Edge 540

[Bunky.F.Knuckle]

If you put the 176 on it, it may fly it fine, but I really feel you are not going to like how it peforms.You will probably have to shove everything including the sink on the nose. Keep in mind, this is a big lumbering ox of an airplane. It has alot more frontal area, drag etc than you H9 Sukhoi. Keep that in mind. You really need raw power, something that can swing a big prop and get some air over those surfaces.

220cc at minimum for this airplane. Can the DLE swing a 34-36" prop with minimal effort and do it efficiently?

 

[Mikeq]

Bunky you may have a point...I once put a 3W 60 side carb on a 1/3 scale Yak and it did fly it but it was sluggish and no way would it ever hover..I think 80/85cc was called for with that plane if you wanted it used to it's fullest potential... however it will be interesting to see if that 176 evo lives up to it's reputation.

 

[Bill Vargas]

The weight of a 3W275 15.5lbs Minus the weight of a 176 8.5lbs = 7lbs of lead in the nose.

The CG range is ahead of the wing tube and thats what those black lines going across the fuselage are for on that particular plane with the wings installed.

Hate to say,,, bad idea with that little engine on that particular plane.

 

[stangflyer]

Taking into the consideration the BH Edge calls for a 275cc recommended.... but at that weight, it comes in at 63 to 68 pounds. I'm also told that it is grossly nose heavy with that motor on it... So my line of thinking is this. Reduce the weight in the nose making it more manageable. Bring all onboards closer to the front that were in the rear needed to balance out the 275..... and balance should work out. By "NOT" putting a smoke system, extras like fuel filters, switches, batteries and etc. just to make it work for the 275, (Not to mention the 80 to 100 oz. fuel tank), I am feeling confident I can bring her in around 50 to 52'ish. Maybe less. Now lets take that 176 on the front of the Sukhoi that yanks it around like a rag doll. Yesterday was again one more testament of that monster. 6600 rpm on the ground. We all know that MOST, not all...but most motors gain around a grand in the air unloaded. I have seriously considered jumping up to a 34x10 on the front of that beast simply because the 32x11 is just not enough. Nor was the 3W 3D 32x8-14. A certain friend that shall remain nameless is running around 7600 in the air with his on a 45 pound Yak. And am told it is a beast. Ok, now taking into the consideration that there is tons of drag and the BH Edge is just, well...just, "BIG", how do I expect it to preform? Not looking for ballistic. Not looking for hard extreme 3D. At around 50'ish pounds and 146" wing span, I'm not looking for anything other than really slow extremely high alpha harriers, slooooow inverted harriers, rolls, big ass loops....and just lots of floating fun. Oh and hoping for a graceful low energy hover. The thing is, I don't need or really want over the top and out of this world performance. I just want to do something that hasn't been done. The next couple of months will be a testament of that endeavor. If it works? Coolness beyond belief. IF it don't? Ah heck....who cares? It's all just a part of the fun. I can't speak for everyones GP 176, but if this motor does what I "THINK" it will do, it'll be a hoot to see it happen, yes???? Video "WILL" be posted here on this thread of the maiden.

What would the plan be after this? Hmm......maybe a 50% Sukhoi on a DLE 120.

 

[pawnshopmike]

The GP176 is a beast for sure. If any engine that size can pull it off, it's the GP.

One thing about it Stang, if its not up to par, you can always swap it out for something else. Since you already own the 176, why not try it! I can't wait to see how it does.

 

[stangflyer]

The GP176 is a beast for sure. If any engine that size can pull it off, it's the GP.

One thing about it Stang, if its not up to par, you can always swap it out for something else. Since you already own the 176, why not try it! I can't wait to see how it does.

That was kind of my thoughts. As I stated in an earlier post, What's the worst that can happen? A need for a larger motor?

 

[Mikeq]

That was kind of my thoughts. As I stated in an earlier post, What's the worst that can happen? A need for a larger motor?

I can't wait to see how it does...this will be interesting...I bet you will be surprised.

 

[Bunky.F.Knuckle]

I think you may be forgetting about the huge drag envelope that Yak 55 is. It is much draggier than the H9 Sukhoi. Granted, the 176 may have the ass to power it. But I feel the flight envelope is going to be VERY minimal. I really feel that you are going to have to be in the power, quite heavily, just to maintain level flight, approx 2/3rds power or better.

Think about safety first and foremost. If you had taken 4# out of the tail area and another 2# out of the wings, and reduced your flying weight by the 6# mentioned, then the 176 "might" be enough to do what you want with it.

Do you really want to experiment with engine displacements and flying on an airplane of this caliber? I would really hate to see your investment and all the time you have put into this.

With an airplane this size and caliber, your best judgement should be to error on the side of caution.

I think that it is great that you are pushing the envelope and trying new things. But it should not be with this model.

Im ready for attacks. Bring it.

 

[Bill Vargas]

The issue about removing or trying to remove weight is the effect it will have on the airframes structural integrity.

I also agree with Bunky>>> I think that it is great that you are pushing the envelope and trying new things. But it should not be with this model.

He's already attacked me,,, LOL

 

[stangflyer]

I think you may be forgetting about the huge drag envelope that Yak 55 is. It is much draggier than the H9 Sukhoi. Granted, the 176 may have the ass to power it. But I feel the flight envelope is going to be VERY minimal. I really feel that you are going to have to be in the power, quite heavily, just to maintain level flight, approx 2/3rds power or better.

Think about safety first and foremost. If you had taken 4# out of the tail area and another 2# out of the wings, and reduced your flying weight by the 6# mentioned, then the 176 "might" be enough to do what you want with it.

Do you really want to experiment with engine displacements and flying on an airplane of this caliber? I would really hate to see your investment and all the time you have put into this.

With an airplane this size and caliber, your best judgement should be to error on the side of caution.

I think that it is great that you are pushing the envelope and trying new things. But it should not be with this model.

Im ready for attacks. Bring it.

I appreciate your insight Chris. And I will not stand for any attacks. Insight and knowledge far outweigh anything else. Believe me, safety is "FIRST" and foremost in my mind. That being said, here are the numbers I am working with. And these I am certain you as well as others will concur with.

SD Extra 260: 3W 157CS, Falcon 32x10, static rpm: 6100, comes in at 41 pounds, 11 ounces dry. Add 50 ounces of fuel, just shy of an addition of 3 pounds. Take off weight: 44 pounds and some change. Flies stable, light and very responsive. Definitely no lack of power.

Hangar 9 3.1 meter Sukhoi: GP Evo 176, Falcon 32x11, static rpm 6600, comes in at 41 pounds, 7 ounces. Add 60 ounces of fuel, just shy of an additional 3 pounds. Take off weight: 44 pounds and less change. Flies like a rocket on rails. Rock solid, more responsive than the 260 and most absolutely not shy in the least on power.

I may not know as much as many of you out there regarding this, but I am using my two big boys to base my judgements of capabilities. Given that the Hemp Edge is just plain "BIG" and will with no doubt have a ton more drag than the 260 or the Sukhoi.

After doing a some lightening in the fuse and fresh weight this evening, (and no structural integrity was compromised) Simple removing of un-need plates from previous owner) Fuse with stabs, canopy, landing gear, tail gear, wings on minus cowl: 34 pounds. Add cowl, batts, servos and hardware including harnesses and misc. hardware: roughly 7 pounds. Add to that the 10 pounds 14 ounces of the GP 176 and pipes, weight is now at 51 pounds, 14 ounces. I plan to use a 60 ounce tank, again 3 pounds for fuel. Take off weight "SHOULD" be around just shy of 55 pounds. Now I do realize that instead of 1/4 to 3/8 throttle, (at half or above it's insane) I am using to fly the Sukhoi.... which anything above that is really not necessary, I figure I will be into at least half throttle on the Hemp. Probably more. But being much lighter than originally designed, I'm thinking it should float nicely and when the gas is mashed, I really think the big boy is going to do just fine.

The only two things that will ultimately deter me from proceeding with this is one: Balance. If it just won't balance then 'nough said. I will not add weight just to get it to balance. It would defeat my purpose completely. Two: Thrust to weight ratio. At present the GP is pumping out a whopping 127 pounds of static thrust. Add the effect of drag and the more than likely lack of authoritive control on the Aileron surfaces and that could be a factor. If the Evo will handle a 34" prop once broken in, then I may be able to overcome the second stopping point. It is really going to be all decided on the next few gallons of the 176 on the Sukhoi.

Believe me, I am not going to risk the Hempel Edge, (not to mention the safety of others) if I just don't feel good about it. Not meaning to sound like a "know it all", but after 21 years flying, I've learned one really definitive truth and it's proven itself many times over. If my gut says "NO". I won't do it.