Douglas D-741 / A4D-4 Skyhawk

[overscan (PaulMM)]

The A4D-4 was a 1958 proposal for a long-range all-weather attack version of the Skyhawk. It would be capable of delivering a nuclear weapon at low altitude. The wing shape was changed from that of a delta to that of a swept tapered shape. The span of the swept wing was increased by about 10 feet over that of the earlier A4D versions, which requred that the outer wing panels be provided with folding. Seven hardpoints were to be installed underneath the wing and fuselage. A larger bubble-shaped canopy was to be fitted.

Text from http://home.att.net/~jbaugher4/newa4_26.html

 

[fightingirish]

Scan from a magazine, found in another forum.
Edit: See also this scan as an attachment in post #21.

 

[Sentinel Chicken]

I think that magazine scan is from a past issue of Wings of Fame.

 

[Antonio]

I think that magazine scan is from a past issue of Wings of Fame.

You're right

 

[Tailspin Turtle]

Any idea what the trailing edge pods just outboard of the wing folds are on that A4D-4?

Could they be Kuchmann carrots(?) like those seen on the Convair CV990 and Handley Page Victor?

That's my guess. It was about the right time frame for the anti-shock concept developed independently by Whitcomb and Küchemann. See: http://en.wikipedia.org/wiki/Anti-shock_body

 

[Tailspin Turtle]

Douglas proposed the J52-powered A4D-4 Skyhawk to the Navy circa 1958. It bore only a passing family resemblance to the A4D-2 or even the J52-powered A4D-3 that preceded it but was stillborn. I had thought that the proposal was not only unsolicited but not taken up by the Navy. It occurred to me tonight that the next Skyhawk upgrade was the A4D-5. It would have been very unusual for the Navy to skip a change number unless it had formally assigned to a contract and allocated Bureau Numbers like the A4D-3. Does anybody have a record of such an action involving the A4D-4?

For the A4D-4 SAC (which didn't necessarily make it an official Navy designation), see Ryan's excellent collection:

http://www.ibiblio.org/hyperwar/USN/SAC/A4D-4_SkyhawkSAC-581114.pdf

 

[AeroFranz]

Kucheman carrots?

 

[Tailspin Turtle]

Kucheman carrots?

Küchemann carrots (after Dietrich Küchemann, a German aerodynamicist), or Whitcomb bodies (after Richard Whitcomb, a NASA aerodynamicist, he preferred "anti-shock bodies"). They apparently came up with the concept independently. They were intended to reduce the transonic drag and improve range by implementing the area rule postulated by Whitcomb

 

[AeroFranz]

I meant, do you know if that's what those fairings are for, or were they there for some more obscure reason (fairing for an actuator/electronic equipment, say). I don't think I have seen wing carrots used for drag tailoring on any fighter.

 

[Tailspin Turtle]

I meant, do you know if that's what those fairings are for, or were they there for some more obscure reason (fairing for an actuator/electronic equipment, say). I don't think I have seen wing carrots used for drag tailoring on any fighter.

I'm all but certain that they were only there for transonic drag reduction. However, I don't have any official documentation that states that.

 

[overscan (PaulMM)]

Additional details on the A4D-4 including 2 beautiful shots of a desk model and a description is on pages 116-117 of Tony Buttler's American Secret Projects: Bombers, Attack and Anti-Submarine Aircraft. Tony states the Küchemann carrots were for drag reduction, the extended wings increased fuel load but required a wing fold.

Images here are extracted from the SAC PDF above.

 

[overscan (PaulMM)]

Looks like its firing a Bendix Eagle (Douglas 742) AAM - Tony mention this but it seems a bit crazy.

 

[hesham]

Hi,

also from Tony Butler's book; American Secret Projects:
Fighters & Bombers;

Douglas D-745 was a weapon system based on carriage
of Eagle air-to-air missile, 13.5.58.

 

[Pioneer]

Looks like its firing a Bendix Eagle (Douglas 742) AAM - Tony mention this but it seems a bit crazy.

Agree Overscan, although I think it is meant to represent a Maverick ASM?

Regards
Pioneer

 

[Tailspin Turtle]

Maverick was a bit later. It is almost certainly a Douglas Model 742 missile, their airframe proposal for the Eagle air-to-air missile, which was won by Bendix/Grumman. A Corvus would have been a more logical choice for this artists concept and is included on the SAC list of weapons as well as the Model 742.

 

[Jemiba]

Just as an attempt to find some reason in this that artist impression: Could there
have been ideas of using the bomber/fighter bomber complement of a carrier
as a kind of "flying arsenal ship" for interceptors like the Missileer ? The dedicated
interceptors, after having exhausted their own AAMs acting as pointers and the
other aircraft as shooters ?

 

[Grey Havoc]

Just as an attempt to find some reason in this that artist impression: Could there
have been ideas of using the bomber/fighter bomber complement of a carrier
as a kind of "flying arsenal ship" for interceptors like the Missileer ? The dedicated
interceptors, after having exhausted their own AAMs acting as pointers and the
other aircraft as shooters ?

You might be on to something there.

 

[fightingirish]

A model at SDASM Curatorial Collection.

https://flic.kr/p/2ixcbSX

 

[F.L.]

My apologies for reposting such an old message, but does anyone have a better quality version of this image ? Especially the part at the bottom: "Skyhawk for sale".

 

[Archibald]

Burn in Hell, Photobucket... (Edit: I can see I'm not the only one with some resent, if not hatred, about that epic quagmire...)

 

[ST21]

Here is a higher resolution version of that page.

Regarding the "Skyhawks for sale" artworks, i think the caption is wrong about the camoed Skyhawks in the top right corner. They look like A-4Bs in Argentine colors and markings to me rather than hypothetical Greek Skyhawks. Even the serials (C-2XX) match those of FAA A-4Bs.

 

[F.L.]

Here is a higher resolution version of that page.

Regarding the "Skyhawks for sale" artworks, i think the caption is wrong about the camoed Skyhawks in the top right corner. They look like A-4Bs in Argentine colors and markings to me rather than hypothetical Greek Skyhawks. Even the serials (C-2XX) match those of FAA A-4Bs.

Thanks, @ST21 !!!!!

 

[JFC Fuller]

Douglas proposed the J52-powered A4D-4 Skyhawk to the Navy circa 1958. It bore only a passing family resemblance to the A4D-2 or even the J52-powered A4D-3 that preceded it but was stillborn. I had thought that the proposal was not only unsolicited but not taken up by the Navy. It occurred to me tonight that the next Skyhawk upgrade was the A4D-5. It would have been very unusual for the Navy to skip a change number unless it had formally assigned to a contract and allocated Bureau Numbers like the A4D-3. Does anybody have a record of such an action involving the A4D-4?

For the A4D-4 SAC (which didn't necessarily make it an official Navy designation), see Ryan's excellent collection:

http://www.ibiblio.org/hyperwar/USN/SAC/A4D-4_SkyhawkSAC-581114.pdf

I just had exactly the same thought and then stumbled on this section in the George Spangenberg Oral History, emphasis mine:

"We obviously needed more capability than we had in the A-4. We had tried earlier to do a swept wing version in lieu of the delta on the A-4 which would have given us the capability, at least it would if we had a fan engine to put in at the same time. But that program, the A4D-3 at the time, had to be cancelled as we ran out of money."

The actual A4D-3 proposal retained the delta wing configuration so it is possible that Spangenberg is conflating the A4D-3 and the A4D-4. In doing so though, he may be revealing that the Navy was involved in, and had genuine interest in adopting, the A4D-4. Perhaps there is a close relationship between the A4D-4 and the 1957 termination of the contract for four A4D-3s?

The comment about a fan engine is interesting, it makes me wonder what an A4D-4 scaled to take the TF30 would be capable of?

 

[hesham]

Scan from a magazine, found in another forum.
Edit: See also this scan as an attachment in post #21.

That's A-Z magazine as I think,I have most of its issues ?.

 

[overscan (PaulMM)]

No its Wings of Fame #5, Skyhawk Variant Briefing Part 2.

 

[BlackBat242]

The comment about a fan engine is interesting, it makes me wonder what an A4D-4 scaled to take the TF30 would be capable of?

Good question.

One way to estimate would be to compare the A4D-4 with either the A4D-3 or the A4D-5 (A-4E), then take the A4D-6 (TF-30-powered enlarged A4D-5 that competed against the A-7 for the VAL competition) figures and alter them by the results of the first comparison.