enginehistory.org

I have just read the following which surprised me :
"...from 1933 to 1937 airlines used 87 octane only to boost take-off power and 80 octane for cruising. By 1937 87 was used for cruising and 90 ...

A belated thank you Kimble. I have not checked the site for a few weeks. It was great that you know people with whom you can discuss your explanation.

As in my first post, the statement I don't understand (despite reading the 'inlet design' article a few times) is "the increased engine airflow really helped the inlet performance".

Q. Ve ...

Thanks for replying. I don't understand though. I thought the thrust came from the pressure in the inlet so unless increased flow improves the pressure recovery there's no increase in pressure and thr ...

With reference to the presentation "How supersonic inlets work"
I have read it again looking for an answer to the question below.

On page 4 of Bob Abernethy's presentation
ref http:/ ...

At the design point what was the AB primary nozzle area, presumably partially closed at less than 100%?
There must have been some excess thrust to get there and no longer needed for cruise at M3.2 on ...

Thank you for pointing out the effects of off-design conditions. I think I see this now in a plot of flight data which shows the ejector exit diameter can vary anywhere between 90 and 100% open above ...

Question 3. Is the nozzle underexpanded at cruise

I should have mentioned I have Paul Herrick's 'J58/YF-12 Ejector Nozzle Performance'. I have just re-read it and it says a shorter nozzle which was ...

Thankyou both for all those details. Now I know what to look for I can see closed doors on a Duxford photo I took.

I have been thrown by these doors ever since reading Paul Crickmore's book 'Lockhe ...

Hi,
I have just read J Thomas Anderson's new addition to the site 'How supersonic inlets work'.
On page 25 he mentions "suck-in doors open at low speeds to maintain small pressure loads on the ...