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  #1  
Old 03-16-2010, 11:10 PM
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Feyd Feyd is offline
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Default A-10 Warthog Design

Well, I finally decided to make one myself and I think it looks pretty good, notwithstanding some odd-looking parts.

Problem is, it doesn't launch no matter what kind of engine I put in it.

Could someone look at this and let me know what I've done wrong?

Thanks.
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File Type: rkt A10 Warthog.rkt (110.6 KB, 92 views)
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  #2  
Old 03-17-2010, 07:39 AM
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Downloaded it and couldn't see anything obvious that wouldn't allow it to launch in the design components..Added a launch lug in my 'tweaking' and it launches fine for me..
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File Type: rkt A10 Warthog V2.rkt (104.0 KB, 71 views)
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  #3  
Old 03-17-2010, 04:32 PM
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A Fish Named Wallyum A Fish Named Wallyum is offline
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Quote:
Originally Posted by pantherjon
Downloaded it and couldn't see anything obvious that wouldn't allow it to launch in the design components..Added a launch lug in my 'tweaking' and it launches fine for me..


Who hasn't taken one to the pad without a launch lug? (Although my personal favorite was the one that I actually attached a lug to, then had it fall off the pad when I went to attach the clips. )
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Old 03-17-2010, 07:52 PM
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Feyd,

The A-10 looks good visually, but the engine selection is actually limited to only one -- the D21-7T. Double-click each of the simulation runs and take a look at the "Launch Guide Length" data. The "B" and "C" engines both require 10' of guide length or more before they reach safe flight speed. In other words, neither are satisfactory to get the model off the pad and fly correctly once lit. This design has a lot of drag with those big wings, and needs plenty of "oomph" to get moving. Now, if only we had a core-burning engine, like the C5, it might be different.

Jon, you missed the "Velocity at Deployment" numbers on those "B" and "C" engines -- both deployed at over 55 FPS, meaning the parachute would likely explode and fail completely the moment it came out.

Having said this...

I wonder if this could be convoluted into a BG?
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  #5  
Old 03-18-2010, 06:14 PM
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Launch lug. <slaps forehead>

Thanks. I changed the engine tube to a BT-50 and loaded a B12-5 in. Launch was to over 900' but velocity at deployment was 32.6'/sec. Wow.

On the other hand, the launch rod would only have to be 34".

I might try building this one. I wonder what would happen if I put engines in the engine pods
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Old 03-18-2010, 06:21 PM
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Very interesting. Here's a modification turning the engine pods into actual engine pods. It shows as marginal stability (0.17 whatever that means) but it seems to fly well in simulation.
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File Type: rkt A10 Warthog.rkt (185.5 KB, 70 views)
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Dale Marshall, San Antonio Texas
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  #7  
Old 03-18-2010, 06:26 PM
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Just as a side note...

The BT5s in the wings are actually supposed to be cut to be below the wings like the real plane. I couldn't figure out how to do that. The wings don't actually have that big gap in them.

Plus for some reason the fins that connect the engine pods are supposed to connect to the whole body tube. I'll have to change them to custom fins.

Plus I'll be shaping the body tube to taper to the rear like the real plane.

If I decide to build it
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