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My next big project since used JT15D's are starting to look "reasonably" priced.

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Kazansky22

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Wait a minute... Kazansky22? As in Tom Kazansky? As in Tom "Iceman" Kazansky?


Should be designing a scale F-14, no?
Hahahaha, you caught me!

But its not really a "scale" anything, I was just using a scale 75% *approx Mirage 2000B in SU just to be a digital concept drawing, just something to start from. I would like planform as close to that original as I can make it but I imagine once all the concessions in design have been made the silhouette will be a little different.
 

Swampyankee

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Just curious, why does everyone go to fighters?
Why not scale down the Concorde or the A6 Intruder?
Both are delta wings, bith carry a lot more fuel then most fighters....
I would think both of them would be a better starting point.

Tim
A-6 had a swept wing. Deltas don't have much of a history with carriers.
 

Riggerrob

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How about something based on the Saab 210 Draken?
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Vulcan versus Draken vs. Concorde wing shape determines forced landing handling.

Forget about Concorde configuration for a single engine, because Concorde had terrible low-speed characteristics. Because low-aspect ratio deltas (e.g. Concorde) develop tremendous amounts of drag at low airspeeds - and high angles of attack - all landings are "powered." In the worst case scenario: a Concorde could get so low and so slow that it could not power/climb out of its own drag bucket!
One way to reduce this risk is to fix undercarriage at the optimum touch-down and take-off angle (e.g. Dyke Delta).

Whether you opt for a full delta (Vanguard) or cranked leading edge (aka double delta Saab Draken) depends upon desired span-loading and wing-loading. Cranked leading edge allows you to reduce wing area (increase wing-loading) without reducing span.

As for tailoring wing leading edges, start with Mirage configuration, then review all the modifications developed by Israel (Kfir) and South Africa (Cheetah).
 

Kazansky22

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One way to reduce this risk is to fix undercarriage at the optimum touch-down and take-off angle (e.g. Dyke Delta).

As for tailoring wing leading edges, start with Mirage configuration, then review all the modifications developed by Israel (Kfir) and South Africa (Cheetah).
I like the way you think.
 

Victor Bravo

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tspear made an interesting suggestion, that you may not be best served by using a tactical fighter as the inspiration. That deserves a second look. The B-57 Canberra might be a good safe "sane" configuration. With the original wingspan you would have a pretty agile and sportscar like experience, but remember the B-57 also was built with a longer span high altitude version (RB-57). So a short and long set of outer wing panels is possible, allowing you to go from the hot dog version to the cross country traveling version on the same main airframe.
 

Lucrum

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It's been 5 years since I've flown anything with a JT15D in it
Aren't the S.L. T.O. thrust fuel burns over 2,000 lbs/hour?
 

Aesquire

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The F5D Skylancer was the successor to the F4D Skyray, with a higher fineness ratio and thinner wings. Mach 2 and serious business. Didn't get the contract. That went to the Vought F8U Crusader, which was a fine machine. ( but the story is Douglas was already making most of the Navy planes at the time and they wanted to save Vought and not have a monopoly going.... ) So NASA got the 3 of the planes that were completed and used them for testing. Including the abort maneuver testing for the Dyna-Soar space plane program.

https://www.nasa.gov/centers/dryden/multimedia/imagegallery/F-5D/F-5D_proj_desc.html

The F4D would do runway to 40,000' in 2 minutes.

https://en.wikipedia.org/wiki/Douglas_F5D_Skylancer

I'm not sure you could do a mini-version of a Douglas A4 without it looking more cartoonish than that most excellent plane already does. Size of cockpit would be marginal. ( the full size plane is one you strap on, not climb aboard. ) Still, you can't go wrong with the aerodynamics.

( pictsidhe beat me to the Avro :) )
 

Kazansky22

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It's been 5 years since I've flown anything with a JT15D in it
Aren't the S.L. T.O. thrust fuel burns over 2,000 lbs/hour?
I think you must be mistaking it with a different engine, the SFC is around 0.562 lb/(lbf·h) or a little higher at max depending on model, and a little better at cruise. Thrust isn't that high, 2100lbs-3000lbs or thereabouts, depending on model.

Anyways, little update, I've finished the Request for Proposal requirements, and made the initial concept sizing/weight calculation.



I'm going to have a friend of mine check my numbers just to make sure I didn't do something completely wrong
Est We is 3600lbs
Est Wf is 1600lbs
Max t/o 5600lbs

I just downloaded solidworks 2017 on my home PC and laptop today along with workstation graphics GPUs, so I've been reading up and watching tutorials on it so I can port the initial concept over and begin making the size change requirements.
 

TFF

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Proposal; are you looking for financing? You are going to try and market this? I hope the 3500hr is engine life and not airframe. An airframe time limit would get a big laugh in the homebuilt market.
 

Kazansky22

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Proposal; are you looking for financing? You are going to try and market this? I hope the 3500hr is engine life and not airframe. An airframe time limit would get a big laugh in the homebuilt market.
No I'm not expecting financing.

Its a RPF to myself. To establish mission objectives to guide the conceptual design process. And yes 3500 hours on the airframe/engine. By Operational life it doesn't mean not expecting to replace anything until that time. Its means the airframe will remain useful. IE doesn't need to be retired due to metal/carbon fatigue due to use. The useful life of material can be estimated.

I want to have everything in writing as I go through the process to keep the idea on track, it would be very easy to start changing objectives along way on a 15 year project.
 

proppastie

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In terms of design....just remember everybody thinks they are a designer, and a good designer is a pirate.....Giving over to a consultant while probably advisable with the scope of this project, he will want to change the design to conform to his prejudices. Good luck.
 
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