Sunday, 8 January 2006

Australian "Black" Defence Projects of the 70s

The Submarine Aircraft Carrier

The Royal Australian Navy Skyhawk, being an all-purpose aircraft, was the subject of a 1970s experimental sea trial of an A-4 on board a Royal Australian Navy submarine. There was no objection from the aviators to operating the Skyhawk from the somewhat limited deck space of the submarine. A problem with the Skyhawk's turbine cavitating while underway submerged was overcome. The diesel catapult worked just fine. However, the experiment was abandoned when the submarine's XO objected to the jet blast burning the paintwork off the sail.
The greatest difficulties were caused by having to provide a rescue helo as well. This caused conditions on board to become rather cramped.

But there was some serendipity from this project. The solutions to the problems of keeping the pilot dry, and especially the ability to launch while submerged, were found to give the vehicle a limited exo-atmospheric capability, when fitted with external boosters.

The vehicles so equipped were not capable of lunar landing, and had to rely on lunar slingshot effects for Earth Return orbit.

Re-entry profile was similar to the shuttle's (whose wings are similar in plan to the A-4's), but cooling was provided by an ingenious spray mechanism (the tanks under the wings), where a cryogenic gas/fluid mixture (Bionic Evaporative Environment for Re-entry) was injected into the boundary layer, preventing much of the frictional heating, and conveying away the remaining heat by convection. An additional spray was installed on the nose, clearly visible in the photo. Also visible are the additional internal spray coolant systems for the tail and wing leading edge, shown with the pop-out panels open during vacuum operations, a precaution taken after one system stuck in the closed position, and only unjammed after a risky EVA manouvre just before re-entry.

The flights were successful, but the experiments were abandoned after the fighter pilots reported nothing worth shooting at up there. It was also found that the ground crew often emptied the self-pressurising BEER storage in order to "check the contents" rather too often.

Pictures and quoted text are from the RAN Shyhawks page. Photographs courtesy of the Australian Naval Aircraft Museum: Mark Clayton, Director;, Windy Geale, Curator

By the way... should some advertisements appear to the left for "Moon Landing Hoax", just remember that
a) I have no control over what adverts appear. Some automated system looks at the posts that are visible, and returns adverts that may have something to do with the content.
b) But I do get a few cents every time someone clicks on one. More to the point, I get it from the purveyors of such egregious BS, so it's a twofer. Especially if someone clicks multiple times.
c) Of course, sometimes something useful appears. Not every advertiser is a totally mendacious snake-oil merchant relying on Idiotarian gullibility and the overly-credulous, in fact, very few of them are. Just the ones trying to propagate the "Lunar Landing Hoax" myth.

Currently, as I'm writing this, no such advert is visible, so I can talk about it. Because part of the terms of service are not to draw attention to existing ads, nor encourage readers to click on them just for the sake of it. Just saying, that's all.

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