Old designs with modern engines

[Weaver]

India decides to keep the Ajeets around and re-engines them with the Adour (sans afterburner) from their shiny new Jaguars.

[PR19_Kit]

Would you be able to see the difference between a J-79 engined A-5 and a Spey engined one though?

[Weaver]

Would you be able to see the difference between a J-79 engined A-5 and a Spey engined one though?

Well the TF30 and Spey/TF41 needed lots more mass-flow than the J-79, so the Corsair had a significantly bigger and blunt-lipped intake. What you could do, as a sneaky what-if, is cut an F-8 kit down to A-7 length, put A-7 wings on it, and claim that in this parrallel universe, the Corsair project went with a J-79 when the TF30 ran into development problems and got cancelled along with the F-111.

Incidentally, there was a serious proposal by LTV for a lightweight, J-79-engined F-8, which was offered as an export fighter to the same competition that the F-5E Tiger II eventually won.

[PR19_Kit]

A Spey engined A-5, not an A-7..............

[Mossie]

Would you be able to see the difference between a J-79 engined A-5 and a Spey engined one though?

The big real world issue with the A-5 was the rear frames holding the J79s, they were integral and defied attempts at re-engining them. That's why the only serious proposal for re-engining it meant adding an extra J79:

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I do wonder if a an F101 engine would be possible though.

[Weaver]

A Spey engined A-5, not an A-7..............

Doh! 

I'd say I should put my glasses on, but actually the PC is the one thing I don't need them for, so I don't even have that excuse.

So yeah, a Spey-engined A-5 would be visibly different for all the same reasons as the Spey-Phantom and the proposed Spey-Mirage IV: bigger diameter engines, bigger diameter jet nozzles, bigger intakes, etc... Essentially it'd be a whole new aircraft.

In theory, the way to do it modelling-wise would be to make the fuselage deeper by inserting a spacer between the top and bottom halves of it. Obviously, this would be much easier if the fuselage was split horizontally the way most F-15 kits are, but unfortunately, on the two Vigi kits I've got (Airfix and Hasegawa), it's split vertically...

[Mossie]

Accidental whiffery led me to the Vought V-1100. An attempt to re-engine the A-7 with an P&W F100 for the LWF programme.  That and cutting and shutting it to the point that it barely resembled an A-7 anymore, yet still retaining some key features.

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[PR19_Kit]

In theory, the way to do it modelling-wise would be to make the fuselage deeper by inserting a spacer between the top and bottom halves of it. Obviously, this would be much easier if the fuselage was split horizontally the way most F-15 kits are, but unfortunately, on the two Vigi kits I've got (Airfix and Hasegawa), it's split vertically...

Somewhere I have a Trumpeter A-5 stashed away, but can't remember how that's split.

And at least one each Airfix and/or FROG A-5s as well. All 'Humpbacks' of course.

[Diamondback]

Ya know, backtracking a bit on the "De-gun the Hog" thing I had an idea on the bus home... Move forward fuel tank into the former drum bay and move engines forward over wings, like a twin-engine Heinkel 162. Either install a small internal weapons bay into the open space, or move more fuel tankage forward to try to move CG more.

And I'm sure we can come up with lighter weight armor equal or better than the Titanium Bathtub...

[Weaver]

Ya know, backtracking a bit on the "De-gun the Hog" thing I had an idea on the bus home... Move forward fuel tank into the former drum bay and move engines forward over wings, like a twin-engine Heinkel 162. Either install a small internal weapons bay into the open space, or move more fuel tankage forward to try to move CG more.

And I'm sure we can come up with lighter weight armor equal or better than the Titanium Bathtub...

The problem with using fuel tanks to balance CofG is what happens as they drain? You need to have them equally placed fore and aft of the CofG, and then you need a system to make sure they drain equally.

Yes, a de-gunned Hog would very probably have to have the engines near the wings, in fact it might make more sense to have them mounted on the wings on overwing pylons. That would span-load the wing, and if the pylons were over the main gears, it would also reduce the wing-root bending moment when the aircraft was on the ground.

[Diamondback]

You mean something like a Cobra Rattler?

[Weaver]

Well without the gun, the other guns and the other engine, yes. Sort of...

[Spino]

Would you be able to see the difference between a J-79 engined A-5 and a Spey engined one though?

The big real world issue with the A-5 was the rear frames holding the J79s, they were integral and defied attempts at re-engining them. That's why the only serious proposal for re-engining it meant adding an extra J79:

You cannot view this attachment.

I do wonder if a an F101 engine would be possible though.

F101 is massive, no way that's going in an A-5.  How about F404 or F414?

[Mossie]

I do wonder if a an F101 F-100 engine would be possible though.

F101 is massive, no way that's going in an A-5.  How about F404 or F414?

Oops.  One digit wrong, big difference. 

[Charlie_c67]

What if Gloster decided to run with the Welland engines for a production model or an axial engine rather than the centrifugal family? Certainly the latter would've given it more power in the end, but at what cost?