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This
is the second of an upcoming serie about my museum-quality 1/32 scale Tamiya F-4
Phantom. The original model F-4J is converted into an F-4S, BuNo 153904. As much
detail as possible is added, wherever possible - aftermarket parts or, most
often, scratch-built items.
The
serie will eventually cover all areas of the model - landing gear bays, access
panels, cockpit, landing gear struts, exhaust nozzles, intakes, etc. The
articles illustrate the conversion process with appropriate pictures, to build a
“how-to” guide that every modeller is invited to use as a reference.
TheF-4
Ram Air Turbine (RAT)
The
Ram Air Turbine (RAT) is a device that generates electrical power in case of
engine power failure. It delivers enough power for about 15 minutes,
before the turbine dies. Normally stowed inside the aircraft’s left side body,
it is deployed by the pilot on emergency. The doors snap open, the fan mast pops
up and the ram air rotates the fan blades. Once deployed, the RAT cannot be
lowered again inflight, and must be serviced by the ground maintenance crew.
| Access
Doors |
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Identifying
the access doors was the first and most important step. Since Tamiya does
not provide any indication of the panels location (recessed panel line), I
had to find out by myself. A good friend of mine was on Phantom
maintenance night shifts, and he could measure the actual size and
locations of the panels on the real aircraft.
The
first photo shows the aircraft’s upper body, with the RAT doors
partially cut out. A gray shaded area must still go,
since I underestimated the actual size of the doors. Uncut areas show the
RAT service access doors: P45 houses the door actuators, P51 is almost
empty, P50 contains the DC generator and the fan actuator. Those panels
will be opened at a later stage (see below). |
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| RAT
Inside
The
inside of the RAT is a scratch-built item, made of white styrene. The
round hole will receive the pad where the RAT turbine rests, when the
device is stoved. Note the various pencil marking lines, where several
items will be glued to.
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| RAT
Inside Unpainted
The
RAT structure approaches completion. The sliver tube is a piece of
soldering wire, that I can bent very easily into any shape.
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| Fan
Mast and Blades
The
construction of the RAT mast, supporting the fan, was tricky. It had to be
removeable, since foreseen accidents will most probably break off such a
weak protubing item. I took a piece of plastic rod, drilled a hole through
it, stuck in a piece of wire, before cutting it to an appropriate length.
I got a neat, solid mast (white part), that I can plug or unplug from the
RAT base. I made the fan with a rod housing (red parts) and hand-crafted
fan blades (aluminum). The quarter gives you a size reference.
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RAT
Unit
The RAT
device, assembled, pained and equipped with all the electrical wiring. Do you
note the white, round fan headrest? When the RAT is stored, the fan’s silver
front dial rests on this pad. The parts for P49, 50 and 51 are still missing,
and will be go to the front and back of the RAT device.
RAT
Unit and P50 & P51
A
view of the RAT unit, with the rear parts P50 & 51 done. The frame below the
unit is a first prototype, hand-crafted from a piece of aluminum. It was shabby,
and I had to redo it later (see photo 8).
Milling Open Panels
Opening
panels 45, 50 and 51 was done with a milling machine, to get a perfect cut, with
straight lines and correct angles.
| Photo-Etch |
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Service
panels are attached to fastener frames, which I had to scratch-build too.
After a first attempt to hand-craft a piece of aluminum by drilling holdes
and filing them into square openings, I looked for a better solution.
Photo-etching came into my mind. Needless to say that nothing exists on
the market in this area, so I had to learn the basics of photo-etching. I
will come pack to this topic in a further article.
Here
are the fastener frames for P48 (left) and P50 & 51 (right) |
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RAT
Access Doors Frames
P48,
50 and 51 are glued into place with tiny drops of CA. I photo-etched also
the RAT doors hinge.
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image below to
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RAT
Finished
The
finished RAT, currently devoid of doors. I can pug and unplug the fan mast. Note
the color of the frames for P45, 50 and 5: yellow-green on the inside frames
(zinc-chromate, standard airframe color) and dark gray on the outside. This
comes from the sealant that is applied when the access panels are closed.
I
hope you enjoy the series, and would like to motivate you to start soon your own
scratch-building project. Stay tuned for the next article on the same F-4
Phantom (wheel wells, photo-etch, J-79, etc).
Pierre
– Scale PhantomPhixer
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