avatar_Bryan H.

F-5, CF-5, T-38, and F-20

Started by Bryan H., January 03, 2005, 10:29:04 AM

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Snowtrooper

We actually considered what was then known as the N-156 around 1960-1 for a brief while, before it was deemed politically unfeasible at the time (along with the F-104G).

Could of course slightly alter the timeline, and fast forward into 1980's, we would have just purchased MiG-21bis's from the Soviet Union, so to maintain neutral stance the next fighter would be from the West - but instead of second-hand Drakens we would seek something more modern but still affordable. The F-20 would be looking for customers, and since the US would probably not have allowed F-16 to be sold to Finland at that time, that could have theoretically been an opportunity. In the Whiffverse, at least ;)

ysi_maniac

Will die without understanding this world.

glorious.tachikoma

Sorry to be bringing the F5 back to the fore, but I was thinking...

I have a thing for conformally mounted missiles like what the F-4 and F-14 did. It just seems super efficient. Pondering the F-5E for another project, I'm thinking of a scenario where a pair of F-4 Phantoms are joined by a pair of F-5Es for an interception mission or CAP. F-5 is already at a heavy thrust disadvantage compared to the F-4 and if you want the F-5 to carry some AIM-7s for the datalinked F-4 to illuminate targets for, that's a ton of extra drag with the missiles themselves and the pylons.

This idea does require new-build airframes but it is a subtle change. The F-5 is not as small an airframe as I'd thought. There is space between the main gear doors and exhausts in terms of length, but I'm sure the fins would intrude in the engine space or intake trunks. But one could mount them right on the corner of the underside of the fuselage, like the F-15A/C. The inboard edges of the wing flaps would need to be moved out a little bit and either the elevators correspondingly trimmed or physically spaced out on their own tiny nacelles to clear the aft fins of a Sparrow.

Of course this would need a different IP with switches for the new stations, a MFD replacing the radar scope to handle the datalink for the F-4 to use the Sparrows (A2A equivalent of buddy-lasing the GBU-12s in DCS) and if thats done then you have the display for targeting AGM-65s...All of this is doable with 1973 tech. Whether a pair of Sparrows would be any more use than a couple extra AIM-9P's or Shafir-IIs...thats another question, lol.

But its still a good idea for a cost-effective way to stretch the power of a squadron of F-4E's.

perttime

If I understand correctly, you are thinking of putting the missiles (two of them?) on the lower corners of the rear fuselage. Perhaps overlapping the rear of the wing and the leading edge of the stabilizer.

One issue that comes to my mind is the balance of the aircraft. Hanging munitions back there would move the center of gravity back - and releasing them would move CG forward. That could be tricky for keeping the aircraft controllable.

Just guessing: that area is probably pretty full of "necessary stuff" creating a little additional space might be necessary.

glorious.tachikoma

Quote from: perttime on March 05, 2022, 10:37:29 PM
If I understand correctly, you are thinking of putting the missiles (two of them?) on the lower corners of the rear fuselage. Perhaps overlapping the rear of the wing and the leading edge of the stabilizer.

One issue that comes to my mind is the balance of the aircraft. Hanging munitions back there would move the center of gravity back - and releasing them would move CG forward. That could be tricky for keeping the aircraft controllable.

Just guessing: that area is probably pretty full of "necessary stuff" creating a little additional space might be necessary.

Well if mounting the missiles on the edges of the "bellypan" for lack of a better term, I don't think there is anything there besides the engines and their ducts, which are round but the bottom of the fuselage is squared off.

And yes, 1000lb of ordnance isn't trivial, but it would probably just be a matter of programming the FCS to trim down a little bit to compensate for the weight. It would be asking the elevators to make a bit more lift which is better for maneuverability than asking the elevators to push down and use the wings as a fulcrum just to stay level (like the F4).

perttime

That area does have some equipment in it. But I am sure there are ways around that.

cutaway drawing: http://aviadejavu.ru/Images6/AN/AN82-3/7-1.jpg

kitnut617

#141
Quote from: perttime on March 06, 2022, 09:09:37 PM
That area does have some equipment in it. But I am sure there are ways around that.

cutaway drawing: http://aviadejavu.ru/Images6/AN/AN82-3/7-1.jpg

Pertti, you've linked to a F-20, which is different to the F-5 at the rear. I've worked on a F-5 (actually a CF-116) and have had a good look up through the engine tunnel. The walls of the fuselage in the rear end are not very thick, plus there's the tail assemble joint in that location too. If anyone has built an Airfix F-5, or has one in the stash, how the tail parts are in the kit is actually how the tail assembly comes off, slanting join line and all ----

Incidentally, the wing attached to the fuselage just like in the kit too plus a large gap under the fuselage which is the wheel bay which is not represented in the kit parts. This is a photo I took of the CF-116 I was working on, the wing is built in one piece, and the 'notch' is the wheel bay area.



In this photo you can see where the wheel bays are.



The above photo is the bottom of this one, which is mounted outside The Military Museum in Calgary (I was redesigning the mounting pole for it)

If I'm not building models, I'm out riding my dirtbike

perttime

Quote from: kitnut617 on March 07, 2022, 05:40:15 AM
Quote from: perttime on March 06, 2022, 09:09:37 PM
That area does have some equipment in it. But I am sure there are ways around that.

cutaway drawing: http://aviadejavu.ru/Images6/AN/AN82-3/7-1.jpg

Pertti, you've linked to a F-20, which is different to the F-5 at the rear. ...
Oops. Looks like searching for cutaways for F-5 found me other designs too, and I only looked at what is in that corner of the fuselage.

glorious.tachikoma

Quote from: kitnut617 on March 07, 2022, 05:40:15 AM

Pertti, you've linked to a F-20, which is different to the F-5 at the rear. I've worked on a F-5 (actually a CF-116) and have had a good look up through the engine tunnel. The walls of the fuselage in the rear end are not very thick, plus there's the tail assemble joint in that location too. If anyone has built an Airfix F-5, or has one in the stash, how the tail parts are in the kit is actually how the tail assembly comes off, slanting join line and all ----

Incidentally, the wing attached to the fuselage just like in the kit too plus a large gap under the fuselage which is the wheel bay which is not represented in the kit parts. This is a photo I took of the CF-116 I was working on, the wing is built in one piece, and the 'notch' is the wheel bay area.

All I can find are reviews for the 1:72 and I'm not quite seeing what you mean. But thank you for that photo of the wing structure. Its cool how that box between the wings can carry the load of that aircraft at 8G.

kitnut617

I have this book all about CF-116's, there's a chapter on all the model kits you can buy of the F-5 and it says the Airfix kit despite it's age and simplicity, is quite accurate.

If I'm not building models, I'm out riding my dirtbike

ysi_maniac

USAF: A pair of simple radarless fighters to attack in Vietnam War

Will die without understanding this world.

thundereagle1997

An f-5 based on the saeqeh but with canards & a bubble canopy would be a great idea

thundereagle1997

An upgraded F-5 based the HESA Saeqeh but with canard foreplanes & a bubble canopy
would be an amazing idea for a great fighter aircraft.

thundereagle1997

A naval version of the F-5/F-20 with a sturdy bubble canopy 2 J-85-GE-21 derived turbofans capable of giving a top speed of
Mach 2 & folding wings capable of carrying air to air missiles.