Author |
Message |
Topic: Use of different octanes in flight |
pkent
Replies: 4
Views: 3931
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Forum: Technical Discussion Posted: Fri Jun 14, 2019 15:52 Subject: Use of different octanes in flight |
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 ... |
Topic: How supersonic inlets work |
pkent
Replies: 9
Views: 6317
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Forum: Technical Discussion Posted: Sun Jan 13, 2019 15:32 Subject: How supersonic inlets work |
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. |
Topic: How supersonic inlets work |
pkent
Replies: 9
Views: 6317
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Forum: Technical Discussion Posted: Mon Dec 17, 2018 15:15 Subject: How supersonic inlets work |
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 ... |
Topic: How supersonic inlets work |
pkent
Replies: 9
Views: 6317
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Forum: Technical Discussion Posted: Tue Dec 04, 2018 10:59 Subject: Re: How supersonic inlets work |
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 ... |
Topic: How supersonic inlets work |
pkent
Replies: 9
Views: 6317
|
Forum: Technical Discussion Posted: Sat Nov 24, 2018 11:15 Subject: How supersonic inlets work |
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:/ ... |
Topic: J58 installation in A-12/SR-71 nacelle |
pkent
Replies: 7
Views: 17560
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Forum: Technical Discussion Posted: Sun Jan 05, 2014 13:53 Subject: design point thrust setting |
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 ... |
Topic: J58 installation in A-12/SR-71 nacelle |
pkent
Replies: 7
Views: 17560
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Forum: Technical Discussion Posted: Wed Dec 04, 2013 20:53 Subject: J58 installation in A-12/SR-71 nacelle |
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 ... |
Topic: J58 installation in A-12/SR-71 nacelle |
pkent
Replies: 7
Views: 17560
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Forum: Technical Discussion Posted: Sat Nov 30, 2013 15:27 Subject: J58 installation in A-12/SR-71 nacelle |
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 ... |
Topic: J58 installation in A-12/SR-71 nacelle |
pkent
Replies: 7
Views: 17560
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Forum: Technical Discussion Posted: Thu Nov 28, 2013 13:50 Subject: J58 installation in A-12/SR-71 nacelle |
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 ... |
Topic: J58 installation in A-12/SR-71 nacelle |
pkent
Replies: 7
Views: 17560
|
Forum: Technical Discussion Posted: Tue Nov 26, 2013 17:23 Subject: J58 installation in A-12/SR-71 nacelle |
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 ... |
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