Turbojets, Turbofans and hybrids

Okay with this post you will understand that my knowledge of such matters is ‘layman’ at the very least.

I have read most of the Typhoon supplement now and although there is a minor discrepancy or two on the whole it looks pretty damned excellent. Especially for the swing role capabilities that even the Tranche 1 will have albeit to a limited extent.

One of the articles that interested me the most was that about the engine. They said the EJ200 was more turbojet than turbofan and I was wondering exactly what the difference was.

I have seen the cutaways of a lot of fighter engines such as the F100, F110, M53, RB199, F404, F414 and of course the EJ200 itself. I noticed that half of the EJ engine is made up of combustion chamber and there is only one set of fans at the front.

Am I on the right track here or am I barking up the wrong intake? I know that turbofans began to replace turbojets in the 1970s so giving the impression that turbojets were ‘old hat’. In short obsolete. However I also read that in real terms a turbojet is theoretically a much more efficient option. Its lighter and simpler but back when they were de riguer (scuse spelling) development seemed to stop on the turbojet concept.

Now it seems I was wrong about this because the EJ200 is a state of the art fighter engine. The 13500lbst figures given for dry power and the 20250lbst figures given for its reheated thrust are ‘only’ its peace time power outputs. Its wartime settings are 15% extra in dry thust taking it to over 15500lbst and in reheat there is a 5% increase taking it to nearly 21300lbst. However the engines are not expected to last ‘as’ long under these conditions and so would require more maintenence. Yet the fuel consumtion is very low even compared to a turbofan and I think it was the fuel consumtion that kicked turbojets into touch in the first place.

What do you think and what can you put me straight on?

Thanks.:)