Saturday, November 14, 2009

Big box in the post yesterday

contained Tamiya's new big scale Spitfire IX. It looks brilliant in the box but the real test comes with the construction. As I mentioned on the AI site, I needed the kit for reference to complete AI's 'RAMROD' that is to be specifically designed for this kit.

As expected, the kit decals arn't accurate, in particular the depiction of JE-J. That's why AI intends to include markings for this a/c.

This blog is starting to become a a model makers blog and to some extent an advert for Tamiya. This is not what this blog is all about. It's intended to cover anything Spitfire related and also a broad spectrum of things relating to aviation history.

Tuesday, November 3, 2009

My view on research and a quick lesson in BGT (Basic Gas Turbines).

Here's a brief comment on research fundamentals.

It's not surprising that aircraft scale modellers have an interest in the history and development of aircraft. Over the years I’ve read many books and articles on WW2 aircraft covering their development, history and operational use. I’ve always found the most interesting and authoritative are those written by veterans or authors who have had the benefit of an aviation related background and training.

Authors with for example commercial level, civil or military pilot training have a great advantage over the self taught, aviation enthusiast writer or researcher with no formal training. This early training provides a solid foundation of aviation knowledge upon which can be added specialist knowledge in various aspects of aviation history.

Recently I was asked to have a look at an aviation article that illustrated just how easy it is for the untrained, enthusiast type to get it wrong. The article amongst other things, included a comment that a rather famous (beautiful wing shape!) WW2, single engine, aircraft had the ability to feather its propeller. Had the author had the benefit of an aircrew background and formal training, he would no doubt have found that suggestion very strange! The ability to feather a propeller is for obvious reasons, something associated with and really only of use to, a multi-engine aircraft. The article also reminded me of how easy it is to simply ‘cut and paste’ diagrams and tables without really understanding what they convey.

Simply collecting old photos won’t and never will provide a solid foundation.



A Diagram for a new age




The above diagram illustrates how a gas turbine engine works by reference to the internal combustion engine 4 stroke cycle of Induction, Compression, Power and Exhaust. The cycle is known as the ‘Otto cycle’ after Dr Nicolaus Otto who in collaboration with Gottlieb Daimler and Wilhelm Maybach, was the first to demonstrate a functioning, four stroke engine.

This simple diagram would be very familiar to any pilot who had undergone conversion training to fly a ‘jet’ powered aircraft. For over half a century it has been used to introduce pilots to the main components and function; intake, compressor, combustors (combustion chambers), turbines and exhaust; of a gas turbine engine. It is a little known fact that this diagrams first appearance as a training aid was not with the allies but the Luftwaffe in Nazi Germany.

Junkers, the manufacturer of the Jumo 004 axial flow, gas turbine that powered Messerschmitt’s Me 262 jet fighter, produced this historic diagram linking the new and radically different gas turbine to the familiar and well understood internal combustion engine. The Me 262 was the first ‘jet powered’ aircraft to enter service during WWII, heralding in the beginning of a new age in aviation. This new age required ground crew and pilots to quickly learn about this new propulsion system and what better way to do so than with a simple, easy to understand diagram. It would have been particularly useful to pilots who work on a ‘need to know’ basis and don’t require detailed knowledge. Obviously the diagram served as merely an introduction to the subject and more detailed training would follow.

It is interesting to note that not a single book has identified the significance of this diagram. The reason is undoubtedly because none of the authors had an aviation background and formal training. They were basically ‘enthusiasts’, like the vast majority of the readers of such books.

The above comments first appeared about a year ago in the FOR of Aero Imageworks. It doesn't really have much to do with scale models and that seems to have confused some people :)