A-10 Thunderbolt II

[Archibald]

This was Northrop entry for the A-X (which was won by the Republic whartog).
More precisely, Northrop finally selected what become the A-9 (very similar to the Su-25)


Look at that : it really look like a Whartog with a propeller!

So Rafa and Arch decided to start a group build around his beauty!
The aim : slaughtering an A-10 and change it into this Northrop design...

[SinUnNombre]

Alright, I know this has been done and discussed before. I bought a Revell A-10 at Wal-Mart last week with this in mind. I assumed it was 1/48 so I could use bits left over from my Revell Hornet. But when I got home, I discovered it was 1/72. I was a little angry, but oh well. Life gave me a lemon, and I'm off to make orange juice from it....

So, what would need to be done to a 'Hog to get it on and off a carrier deck? I can see 3 areas that may or may not need attention: The wings, gear, and launch/arrestor equipment. The landing gear is the easiest. The A-10 is designed for rough areas so that might not even be a problem. The arrestor hook and tow bar can be scratchbuilt and added with little effort. And the wings......so many options. They need to be folded, but how? Obviously the traditional up-and-over would be the easiest, and you'd probably want another small fold at the tips to reduce your vertical clearance. If you wanted to really get into it, look great doing it, and reduce your vertical to the minimum, you can do a Grumman-style  fold to the back. I would love to pull that off, but how? Is there anything else I need to worry about? Thanks for your input.


Jon

[elmayerle]

Regarding the wing folding, it, of necessity, has to be outboard of the main gear, how far outboard depends on your folding method.  I think you've got room to do a single-fold of the up-an-over style, possibly with a brace 'tween wingtips while folded.  For the rotate and fold aft "Grumman" style, take a look at the wing folding mechanism on a F4F, F6F, or TBF; I could argue, though, that the wing fold of a F7F would be more appropriate.

You'll likely also need to tweak the nose gear with twin wheels, if it doesn't already have them, and the catapult hook such as the F-18 and F-14 have.

[tinlail]

I am working on one, in a very slow build.

I chose to do the wing fold the Grumman style, however I reversed it so that the underside of the wing shows to the outside. My logic is that some pylons will stay on the wing in spite of the fold.

I have no idea if carrier operation rules would allow this.

[ytown2010]

also, what will the tailhook look like? i.e. which aircraft are you going to cannibalize it from?

[SinUnNombre]

The launch tow bar, arrestor hook, and the second wheel for the nose gear(Idon't think it has one, Evan) will all be scratchbuilt/kitbashed to fit. I REALLY want to do the Grumman fold. It will look the coolest, and it will keep the vertical height down. And it should allow the pylons to stay on the wings, as Tinlail said. I hope to get started on it soon, and finish it in USMC colors. Thanks for the quick replies.

Jon

[jcf]

Something to remember is that the nose gear is offset to starboard rather than being on the centreline due to the space taken up by the cannon installation. I don't think you'd have room for a dual-wheel nose gear because of this offset, also I'd be leery of the gear being able to take the stress of a launch without a great deal of redesign, never mind the asymmetrical forces involved. Perhaps a bridle arrangement would be better.

Another option on wingfold is the S2F style, seen here on a drawing of the proposed S2F-4.


I did some figuring on a web-foot Warthog some years back and one thing I decided was to use a lightened 3-barrel version of the GAU-8 to reduce the weight in the forward fuselage.

Jon  

[tinlail]

The S2F fold seems to me to make a lot of sense. I suspect that my A-10 will look like it should tip back on it's tail with the wings folded.

I just have to much sense of symmetry to make angled cuts like that on a wing ...

My plans for the launch bar and the tail hooks a basically triangle of rod coming from the wing roots to the center line both front and back. One will be the tail hook the other will be the launch bar, that is completely separate from the nose wheel.

[elmayerle]

I think I'd move the catapult bar a bit farther forward, or are you going to set it up for a launch bridle?  In some ways, that might make more sense.

In any case, I'd say either the S2F fold or the Grumman fold with the wings rotating to have the underside facing out would be best  I'd figure the main portion of the hinge mechanism is built into the main spar with a locking mechanism connection the inner and outer sections of the aft spar.  As for where to fold, given that the existing A-10 wing has a center section with outboard panels and the mate joint is just outboard of the main gear sponsons, that would be the logical place to put your hinge.  The biggest drawback is that a dry bay is going to be required for the hinge mechanism and this will impact the fuel tankage in the wing center section.

[ytown2010]

elmay, yer reading my mind! and sin and tin, i'm working on whipping up a profile for this.

[tinlail]

My notion is for a rigid bridle, attached to the wing roots instead on the main landing gear. The wing roots seem like the strongest part of a plane, I might add something to suggest stiffeners fasten to the underside. In operation the  front wheel retract and the the launch bar would come up as a separate movement. When you have a plane as slow as the A-10 add extra parts to the outside for the marines seems like a reasonable trade off.

My wing fold is at the edge of sponsons, but I am extending the wings by the size of the fold mechanism. This also allows all the flaps to stay the same as before. In theory the impact would be only the weight of the mechanism. The wing tips will probably lock to the tail fins in the stored configuration.

[elmayerle]

That works if you put the mechanism and structure outboard of the sponsons, it'll also be outboard of the fuel tanks and you'll not impact the fuel quantities.  I could scan a cutaway if you're interested.

[tinlail]

I could scan a cutaway if you're interested.

That would be great.

[ytown2010]

tin and sin here ya go. USMC A-10 with VMA-224 (AW) "Bengals"

[elmayerle]

I could scan a cutaway if you're interested.

That would be great.

It'll probably be this weekend.  I'm looking at the wing structure and while the rotated and folded back wings look great, I'm not certain but what a simple fold might be more structurally efficient.  There's got to be a weight trade-off somewhere, there.

Oh, I also suspect your nose gear may need a strut holding it from the front, too, to handle catapult and arrested landing loads.