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Old Jun 17, 2012, 03:06 AM
deltas are cool
AIR SALLY's Avatar
Tehachapi ,CA.
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the later F-5 had bigger inlets ....i thought you guys were working on a smaller sized plane one that would work with a single 90mm fan .yes what ever you do it will need full ducting to get the bet performance.im pretty good at making ducts...think i've made about 200 at least
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Old Jun 17, 2012, 06:38 AM
Hey Guys, Watch This.......
mike2663's Avatar
USA, TX, El Paso
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I was under the impression we were talking something smaller than 1/4 scale also. Although impressive wouldn't something a bit smaller attract a larger market? 144 inches is larger than most would want to haul around and storage would be a issue..

Mke
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Old Jun 17, 2012, 08:21 AM
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United States, TX, Grand Prairie
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Originally Posted by corsair nut View Post
my scratch built 1/8 scale F-5 is perfect size for single 90mm. its 74" long with a 38" wingspan
This would be very nice....light...and simple...
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Last edited by erh7771; Jun 17, 2012 at 08:47 AM.
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Old Jun 17, 2012, 08:28 AM
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Originally Posted by LuvEvolution7 View Post
I prefer The look of the T38, but you may have to cartoon the inlets a bit, or god forbid, add cheater holes. YUCK!!!!!!!!! Hope you can make a scale inlet work, so we don't have to resort to the two options above that everyone hates.

Your welcome Lee. I wasn't used to guys calling them LEX's till I came on these RC forums. LOL.
I would think On a 74" long jet the inlets would be ok for a single 90mm

ICBW

If the AUW was around 9 - 10 lbs with a 3000 watts of power it's open to a lot of options
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Old Jun 17, 2012, 08:45 AM
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Originally Posted by eaticus View Post
How about single 90-100mm? the market would be bigger and would be easier to transport.
+1

Even a 72" inch-ish jet that has been LS'd can be kept around 9lbs

There are some low cost 90mm systems that can put out 8-10lbs of thrust pretty easy.

The wing loading on the model would be pretty low also...

Very interested in where this goes...
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Old Jun 17, 2012, 09:04 AM
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Whoa, I thought the whole idea was to make a kit for the size that Andy and CN have scratch built !!

What happened?
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Old Jun 17, 2012, 09:09 AM
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Originally Posted by awrightbrother View Post
Whoa, I thought the whole idea was to make a kit for the size that Andy and CN have scratch built !!

What happened?
We looked up the cost of a trailer to haul the jet
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Old Jun 17, 2012, 09:26 AM
Hey Guys, Watch This.......
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Originally Posted by awrightbrother View Post
Whoa, I thought the whole idea was to make a kit for the size that Andy and CN have scratch built !!

What happened?
How many 1/4 scale 144 inch T-38's would you sell vs over say a 74inch? It's your call be but I would guess the later would out sell the larger version. Not everyone is willing to shell out the money for that size kit then there's the retracts and so on. Why not crunch the numbers and see what approximate cost would be?
.
Mike
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Old Jun 17, 2012, 12:19 PM
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For your consideration...

I can't speak for everyone, but I wanted a T-38!
The market really does not have a affordable t-38 kit.

Bob Fiorenzo's kit is really nice, but it is $1K. (I am at the verge of buying this one...)
Sunset Model's kit is affordable, but very poor quality. (I've seen his one in-person)

I can't think of any other T-38 kits/ARF/RTF/etc...

Of course there is always the scratch build option like Jetset44 & Falcon5.

I have printed out the 3-view at 78" fuselage length. I think it would work with single 90mm-100mm.
I can already picture a low cost, well engineered foam kit with a Knife-Liddle Fan system!
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Old Jun 17, 2012, 07:08 PM
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Originally Posted by eaticus View Post
I...
I have printed out the 3-view at 78" fuselage length. I think it would work with single 90mm-100mm.
I can already picture a low cost, well engineered foam kit with a Knife-Liddle Fan system!
If by low cost you're thinking 4-600 usd flight ready i'm in
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Old Jun 17, 2012, 08:12 PM
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At 144" length the each duct intake area was 12 sq in.

At 72" length, the area goes down by a factor of 4 i.e. it will be 3 sq in.

If we use both ducts to feed one 100 mm fan we have 6 sq in feeding a 9 sq in FSA

It won't work
Fahim
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Old Jun 17, 2012, 08:59 PM
Fly more Foam
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United States, IN, Sellersburg
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The smaller size was and still is my intent but Fahim has a valid point.............if it is built to scale. What percentage of diviation would be an acceptable range to allow for a bigger intake but still "look" scale. You wont know unless you had a 3view right next to it to compare.
144", that would truely be a "WOW"-planes under taking to kit. When the trailer or vehicle, oopss, semi!, is needed for transport to the field, this takes the "fun" away from the hobby. Not to mention the flying area of the likes that Andy has on the dry lake bed to fly.

Anyone might have access to one of Bob's kit and mesaure those intakes????????
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Old Jun 17, 2012, 09:37 PM
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At 78" fuselage length, the intake should be about 84% FSA for 90mm.
At 85", should be about 73% FSA for 100mm.
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Old Jun 17, 2012, 09:39 PM
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Originally Posted by erh7771 View Post
If by low cost you're thinking 4-600 usd flight ready i'm in
That is what I am thinking too!
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Old Jun 17, 2012, 10:03 PM
Capt. Z
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United States, NV, Las Vegas
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You can size up the kit just a little and have the nose section in front of the inlets removable with 4 easy screws like my big one has for easier transport.

Mine is transported to the flying site in a regular super crew pickup truck with a 5 foot bed. An 85" or 90" long T-38 would be quite easy to transport if the nose section was removable.
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Last edited by falcon5; Jun 17, 2012 at 10:09 PM.
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