Profile F4 Phantom

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Getting a jumpstart on next years reed speed

nice f4!

Nice, very nice. I will be watching for the linkage set-up. Should be interesting. Is the wing made of foam? Just looks like it due to size and the appearance of tape on the edges and joints.

That's definitely gonna be different! If you could only figure out a way to leave a nice thick black exhaust streak behind it.

So I'm not the only crazy one in this bunch! It appears that you have the 45" minimum wing-area for reed-speed.. but do you have the 15" min. span? It looks a little shy of that..

roddie wrote:So I'm not the only crazy one in this bunch! It appears that you have the 45" minimum wing-area for reed-speed.. but do you have the 15" min. span? It looks a little shy of that..

Ha ha, I actually built this because I liked the jet you built. My the wingspan is right at 16 inches.I'm a little worried how I'm going to balance it out, I might move the wing fwd a little.

cox24711 wrote:nice f4!

Thanks Greg

NEW222 wrote:Nice, very nice. I will be watching for the linkage set-up. Should be interesting. Is the wing made of foam? Just looks like it due to size and the appearance of tape on the edges and joints.

Thanks New, The wing is just cardboard, Not sure if I'm going to keep it like that or make one out of balsa

ARUP wrote:That's definitely gonna be different! If you could only figure out a way to leave a nice thick black exhaust streak behind it.  

actually that would be two big black streaks. ha ha......I got a ride in one back when I got out of the airforce. Quite a different bird when you are sitting in it going Mach II.What a blast that was

akjgardner wrote:url=https://servimg.com/view/19124486/81][/url]

Very nice. I used to work on the Air Force versions back in the late 1960's in Japan.
    Loved that plane.

happydad.

happydad wrote:

akjgardner wrote:url=https://servimg.com/view/19124486/81][/url]

Very nice. I used to work on the Air Force versions back in the late 1960's in Japan.
    Loved that plane.

happydad.

Thanks happy dad, I worked on the F4E at Moody AFB from 81 to 85..... Great airplane

akjgardner wrote:

roddie wrote:So I'm not the only crazy one in this bunch! It appears that you have the 45" minimum wing-area for reed-speed.. but do you have the 15" min. span? It looks a little shy of that..

Ha ha, I actually built this because I liked the jet you built. My the wingspan is right at 16 inches.I'm a little worried how I'm going to balance it out, I might move the wing fwd a little.

No kidding.. well.. as they say; "no balls.. no glory.." I'm glad you like my T33. I like your F4!! Radical stabilator you're designing there! I think there's a lot of merit to having some airstream-deflection forward of the hinge-line.. even with a fixed stab. I think it can help pitch the tail in the presence of turbulence off the wing.. but that's just a guess.

My uncle was an F4 mechanic in the U.S Air Force back in the early 70's.. so it was the first jet I ever really learned about. He enjoyed flying models back then, He, my grandfather and my dad flew control-line together. Another guy who flew with them had a dyna-jet powered F86!

Well Joe ,That's as fine as frog hairs there , glad to hear your wanting to get in on the action . Maybe I should start on something as long as it takes me to work out the details at the end of a build Eric

rsv1cox wrote:Wow, a flying tail on a ukie, gotta see that.  Has it ever been done before?  Ought to change attitude right now!  There would have to be some limits to the movement.  

I always loved the F4, it just looks evil, but the test pilots at Pax River in Maryland didn't like to fly it.  Took to many computers to keep it in the air, but they loved the A4 Scooter.

Yes , I plan on putting limits on it. and yes the F4 is the only fighter that I know that looks like it was over G'd and Under Gd at the same time

getback wrote:Well Joe ,That's as fine as frog hairs there , glad to hear your wanting to get in on the action . Maybe I should start on something as long as it takes me to work out the details at the end of a build Eric

Thanks Eric. I thought I'd get an early start on it. I'll probably be rushed to get it done at the end anyway.I always seem to have 4 0r 5 projects going on at the same time.

rsv1cox wrote:Wow, a flying tail on a ukie, gotta see that.  Has it ever been done before?  Ought to change attitude right now!  There would have to be some limits to the movement.  

Bob, the Cox PT19's stab. is somewhat like that. With "up" input; it's leading edge actually drops below the pivot-point. Mine has what I'd say; a 30/70 split to where the pivot/hinge-point passes through the tail. Cox's design works.. and holds up to abuse.. which is a testament to good "Plastic Flying Model" engineering.

Scratch-building a stabilator isn't nearly as easy as hinging an elevator onto a fixed stab. It's essentially a tube (or pin..) within a tube (close-fit) .. with the outer being the sleeve-bearing. The sleeve-bearing is subject to stress.. and should be supported by (run inside) hardwood plates or an inset block for a profile fuse. It would quickly egg-out even hard balsa because of the horn being located off-center. The same larger size tube becomes the receiver on one side; for the smaller/longer pin or tube on the other. Then comes shimming to keep the stab.-halves from contacting the fuse.. and fusing the two halves together to move as one unit. That's my interpretation of it anyway. I'd like to try building a tail that way someday. I like the look too.

That's a mighty fine looking F-4 there. Can't wait to see flight video. Just eyeballing the pics, I can't really tell how much stab area you have ahead of the hinge line. For your first flights, I'd be really careful to set my throws to minimum for the first flights. You don't want to over-control the puppy.

The Conservative Mark

Hey Joe.. where you going with that model-airplane in your hand.. (sorry.. had to make the Hendrix reference)

Have you done any more work on this jet? I love what you started! There hasn't been much speak about a future speed-contest.. but that shouldn't halt the build.. especially where you have some considerable time invested (me too, with the T-33) We should share concepts on a take-off dolly.

I really want to build one that works.. but there's a lot of variables to consider. Most of the dolly's I've seen are flat/level. My idea.. is to build-in some positive "angle-of-attack" to assist the model's lifting-off/out-of the dolly when it's take-off speed reaches that point. If the dolly is built-light enough; the model's ground-speed should be fast enough to generate enough lift to launch the model with neutral-elevator. This might help prevent "over-controlling" the model once it starts to fly.

A delta-wing will fly like a rocket.. and you'll want to have a chance at levelling it out "early-on" if possible.  

A dolly could utilize a "stooge-launch" if needed.. but even if assisted by a pit-man; it should have some tracking-adjustment tangent to the flight-circle. If the dolly only tracks straight-ahead; it will likely "crab" when the lines tighten.. and tip inward; slowing the take-off speed.. and fouling the launch. The pilot can always take a step or two backward, with a dolly that tracks into the circle.

https://www.youtube.com/watch?v=W3JsuWz4xWc

Hey Joe, you going to getback on that machine soon ?!!??!

ha ha , the Jimmy reference was cool, Thanks for the kick start on the f-4, I need to finish it up. Iv'e been busy converting a couple of comet superstars models into " I can,t beleive the they,re not cox models".one is a fw 190 the other is zero. A baby bee fits on the nose real nice. They are about the size of a cox pt19. as far as launching the f4, I think i'm going to have my son hand launch it over a soybean field.I do want to build a couple of stooge's. actualy , i was going to build one like the one you built.Thanks again for the comment on the Phantom.