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1/32 Electric Intruder - Grumman EA-6A Conversion


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Electronic Warfare (EW) was the Electric Intruder's raison d'etre. Its primary jamming system was the Raytheon ALQ-76, a set of powerful transmitters housed in a large streamlined pod, up to five of which could be hung beneath the wings and fuselage.

 

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Each of these pods had its own electrical generator that was driven by a nose mounted ram air turbine.

 

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To my knowledge there are no commercially produced ALQ-76 pods available in 1/32 scale. The closest thing would be the ALQ-99's that Trumpeter provide in their EA-18G kit (the -99 is a follow-on version developed for the EA-6B Prowler). At first glance the two pods appear very similar. But, upon closer inspection, they differ importantly in both shape and dimension. The -76 has a rectangular cross section and is narrower and shallower than its successor.

 

I decided to start from scratch.

 

Encouraged by my success with the vacuum formed tail pod, I put together a couple of mold halves, this time using basswood as a medium (recalling that the epoxy putty used on the tail pod took a long time to shape and sand).

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And the formed plastic shells. Once again, it took a few attempts to achieve success.

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The half shells were removed from the carrier sheet, cleaned up, strengthened internally, then carefully joined together with Tamiya Extra Thin Cement (TETC) - so far so good.

 

But seam work proved difficult, the thin plastic bodies not holding up to the filling and sanding process. I vacuum formed a new set using thicker styrene, but these proved troublesome as well. Back to the drawing board...

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...I settled on a less exotic approach. The vacuum forming machine was set aside, and new pods were fashioned from .030 sheet plastic using "slab-sided" construction techniques. As the basic cross section is a rounded rectangle, internal gussets were installed so that a radius could be formed around the edges. More internal solidification was required around the nose of the pod where it tapers sharply to a circle. Internal detail, visible through the open tail section, was added.

 

A series of four rectangular facets is plainly visible along each side of the pods. They are most likely heat dissipaters, as they stand out in the slipstream, exposing plenty of surface area to the relative wind. Often two of the panels, usually the first and third along each side, sport what appear to be cooling fins.

 

Good close up photographs of the ALQ-76 are hard to find. But here's a look at its successor, the ALQ-99 (used on Prowlers and Growlers), with heat sink panels clearly visible...

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Eduard makes a photo etched metal "armament" accessory set for the Trumpeter EA-18G that includes these heat transfer fins. I chopped eight of them to size using a "guillotine" style precision cutting tool.

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The metal panels were given a sheet plastic backing to create the proper scale thickness. This backing also made installation easier. Each section was laid into position along the pod and held in place with small strips of masking tape. Then TETC was lightly applied around the edges, producing a strong clean bond.

 

The nose of the pod consists of two cone-shaped sections, each with a different taper. Suitable parts were found after rummaging through my large un-built (mostly never-to-be-built) collection of kits.

 

Using shaped plastic rod and thin styrene card, the four bladed turbines were put together. After paint and decals, they were photographed and put away for safe keeping.

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Additional details include the six mooring points along the top edges of the pod, fashioned from .005" plastic card, and the pylon mounting hardware created from brass tubing.

 

Panel lines and fastener detail were applied per references.

 

Tamiya Fine Surface Primer (white) spray paint was applied, straight from the can, as my airbrush was out of commission at the time. But as many of you know, this product when applied in thin coats lays down beautifully. Although labeled a "primer," it makes a fine finish coat too - tough and fast drying, with a pleasing "eggshell" luster. Good stuff.

 

The decals are from Furball Designs Electric Intruders sheet 48-027. Although intended for the 1/48 scale Revell kit, they proved quite suitable for this project.

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That's all for now. I really appreciate all of the support and encouragement I've received to this point. Thanks a bunch!

 

Rich

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  • 1 month later...

Work continues on the under wing stores - this time the AN/ALE-32 external chaff dispensing pods.

 

Resembling fuel tanks (they were adapted from the Aero-1C 150 gal. "streamline" series), they could be mounted on any of the EA-6A's seven hard points. They were commonly seen attached to the "lightweight" outboard wing stations as illustrated here...

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These pods were in use through the 1970s before being replaced by the bulkier AN/ALE-41 dispenser.

 

I'm not aware of any commercially produced -32s in large scale. I thought perhaps I'd have better luck finding an Aero-1C fuel tank in 32nd scale - these were used on Skyraiders, Cougars and early Skyhawks - but alas, nothing turned up.

 

So once again, I consulted my "spare parts inventory" and large collection of un-built kits - which, by the way, is becoming less a source of burden and guilt as I continue to find "hidden treasures" that have proved invaluable for this project.

 

I discovered that an F-4 Phantom II 600 gal. centerline fuel tank in 1/48 scale provides a good starting point. The dimensions and tapers, at least through the nose and mid sections, are practically spot on. To achieve the scale 180 inch length and the proper rear taper, a segment from Trumpeter's 1/32 scale A-6A Intruder 300 gal. external fuel tank was carefully grafted on.

 

By chance, the Trumpeter parts had already been rendered superfluous when I decided to substitute a pair of more accurate Hasegawa 300 gal. Aero-1Ds (from their large scale Skyhawk kit) - a happy coincidence.

 

Here are the sectioned off parts - on top the 1/48 600 gal. tank from a Hasegawa Phantom ll kit, and below, the sexy, but inaccurate Trumpeter 1/32 300 gal. Aero-1D fuel tank from the base Intruder kit.

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these sections were used...

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After the pods were assembled, contoured and cleaned up, rectangular slots were cut along the bottom to create the twin chaff ejector ports. These openings were lined with thin sheet plastic, curved where appropriate to match the pod's radius.

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3/16 inch holes were drilled topside to accept brass tubes used to depict the mounting hardware and electrical umbilicals.

 

Scribing accurately over compound curves is always a challenge. After testing out a few ideas, I settled on the following technique. For the girth lines, appropriately sized brass tubing, inlayed with vinyl tape to provide a friction fit, was pressed onto the pod providing a circular guide for my scribing tool.

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The tail fins were fashioned from .015 inch plastic card. Two small slits were cut into each fin to accept small diameter rods (stretched sprue) that served as mounting pins. Tiny displacement rings, punched from thin plastic card, were looped over these pins before installation, creating a realistic gap between pod and fin.

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continued...

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A finished AN/ALE-32 chaff dispenser posed alongside an ALQ-76 Jammer Pod...

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And another family photo...

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As the major fuselage mods, nose and tail, are also complete at this point, it becomes, more or less, a basic Intruder build going forward. Hopefully the pace of progress will pick up now, although I'm in no hurry - I've learned you can't be.

 

It's all about the journey anyway!

 

Thanks everyone, onboard and off, for your continued support and encouragement. It really means a lot to me.

 

Bye for now,

 

Rich

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Wow, those ALQ-76 pods and the dispenser pods are masterpieces! I guess, some guys here would like to see them in resin. Are you perhaps thinking along those lines?

 

Great progress. I always had a sweet spot for those "electric" birds myself, so I'll be watching this one.

 

Cheers

Rainer

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