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Blackbird SR-71 Flight Manual (2010)

sr-71.org

81–90 of 156 posts

Re: Blackbird SR-71 Flight Manual (2010)

#81
post #67

Chart of speed vs altitude: https://www.sr-71.org/blackbird/manual/5/5-9.php

Does anyone know what the break in the Minimum Airspeed Restriction at Mach 1 is about?

Yes, Google for "Mcrit" or critical Mach number. It's the free stream airspeed at which any part of the airflow over the aircraft first becomes sonic. Usually the inner part of the wings near the root, the thickest section.

Airliners have the same but it happens below M1.0 because of the thicker wings. And it causes a much bigger change in drag and lift compared to an aircraft capable of super sonic flight, enough to make it impossible to take an airliner super sonic without losing longitudinal control and crashing.

Re: Blackbird SR-71 Flight Manual (2010)

#82
For some not so heavy reading for SR-71 enthusiasts, I highly recommend Brian Shul's book "Sled Driver". They are out of print now I believe, and I've seen them on eBay for about $3000 at one stage, but I think they are more generally available at reasonable prices now second hand. I was lucky enough to be given a copy as a gift by a friend a couple of decades ago.

Beautiful book with amazing pictures and stories by a long time SR-71 pilot. A lot of the 'urban legend' stories going around about the Blackbird come from that book.

"Skunk Works", as mentioned by other posters here is also a good read.

Re: Blackbird SR-71 Flight Manual (2010)

#83
post #27

Earlier quoted context omitted.

Yes, airplane check lists do tend to make sense. Still, there is some humour in the laconic terseness and finality of that checklist, which is probably why it was brought up.

It's an emergency checklist - of course it's terse. I don't know what people expect.

Don't worry, it's just humour being subjective.

Re: Blackbird SR-71 Flight Manual (2010)

#84
post #33

Earlier quoted context omitted.

If you enjoy such gems, check out the procedures for C130 transport aircraft. An old colleague used to be a load master on them (before going into tech), and said the action required for a situation where your load is jammed on exit and you can’t cut the chutes deployed to extract the load from the cargo hold is “prepare for crash landing”. I do enjoy the bluntness of military checklists.

I just checked a modern copy I have lying around and couldn't find that particular phrasing. However there are lots of other gems such as "a malfunction of the extraction system that causes cargo to move can be extremely hazardous." Oh really. You don't say.

Related: https://en.wikipedia.org/wiki/National_Airlines_Flight_102

Re: Blackbird SR-71 Flight Manual (2010)

#85

I remember being reported that SR-71 missile evasion procedure was simply to "accelerate and outpace". But I cannot find it in the manual :( !

This is what you are looking for: http://www.onceagreenberet.com/wp-content/uploads/2008/02/sr...

To think of it - I might have heard these two pass by. Not on that flight, but I lived with my parents in northern germany, not far from the danish border, and en route from the north to the baltic sea and on to russia. I often heard the badam, accompanied by a creak of the wooden roof.

Re: Blackbird SR-71 Flight Manual (2010)

#86

A comment[0] by ehnus[1] from last time this was submitted[2] said: > My favorite section is emergency procedures which contains gems like this: > "If both the A and B hydraulic systems fail as indicated by illumination of the A HYD and B HYD warning lights and confirmed by loss of A and B hydraulic pressure and deteriorating control effectiveness: > 1. Eject" ======== [0] https://news.ycombinator.com/item?id=1338777…

Must be nice to have that luxury. The same emergency in the AH-1Z basically says "good luck." Granted, a hydraulic failure of two redundant and independent systems is astronomically unlikely (and the outcome will almost certainly be fatal).

Re: Blackbird SR-71 Flight Manual (2010)

#87
post #86

A comment[0] by ehnus[1] from last time this was submitted[2] said: > My favorite section is emergency procedures which contains gems like this: > "If both the A and B hydraulic systems fail as indicated by illumination of the A HYD and B HYD warning lights and confirmed by loss of A and B hydraulic pressure and deteriorating control effectiveness: > 1. Eject" ======== [0] https://news.ycombinator.com/item?id=1338777…

Must be nice to have that luxury. The same emergency in the AH-1Z basically says "good luck." Granted, a hydraulic failure of two redundant and independent systems is astronomically unlikely (and the outcome will almost certainly be fatal).

Well in that particular case it’s probably still a better option than ejecting.

Re: Blackbird SR-71 Flight Manual (2010)

#88

Earlier quoted context omitted.

Basically, satellites took over They are cheaper to operate and less vulnerable to defensive countermeasures and other failure conditions. From a Los Angeles Times article from '89 [0]: > "The Air Force decision to retire the Blackbirds in 1990 is based on several factors. In congressional testimony, Air Force Chief of Staff Gen. Larry D. Welch identified the increased survivability of reconnaissance satellites, SR-7…

They took over, but there’s still an argument for spy planes; satellites arrive on their own schedule in predictable orbits. This makes it very hard to get timely photographs, and it makes them easier to defend against. A spy plane could get in and out of a trouble spot within an hour, all before the enemy can hide the nukes or whatever. A modern spy plane however would have to be faster than the SR-71, which I don’t…

The X-37B is likely a test platform for exactly that scenario (and more).

Re: Blackbird SR-71 Flight Manual (2010)

#89
post #26
post #18

I once got around two thirds through a certificate for flying ultralight planes. It sort of stopped making sense to me when we were practicing emergency landings over forest and I was told to aim for trees with thinner trunks. This is sitting inside a cramped metal can with the engine in your lap and propeller in your face. There are so many ways to die in that situation that focusing on the diameter of tree trunks w…

I would think you'd want a good clump of green tree canopy to hopefully take the impact "slowly" and stop the plane without the sudden smashing associated with crashing. Such as: http://www.fox5ny.com/news/plane-stuck-in-tree-idaho

Perhaps the smaller trees would be more likely to bend/snap, absorbing more energy

Re: Blackbird SR-71 Flight Manual (2010)

#90

A comment[0] by ehnus[1] from last time this was submitted[2] said: > My favorite section is emergency procedures which contains gems like this: > "If both the A and B hydraulic systems fail as indicated by illumination of the A HYD and B HYD warning lights and confirmed by loss of A and B hydraulic pressure and deteriorating control effectiveness: > 1. Eject" ======== [0] https://news.ycombinator.com/item?id=1338777…

In a similar vein, page 3-135[0] describes what to do when e.g. under missile fire ("the pilot is authorized to use the tactical limits listed...to exit the hostile area by the most expeditious means... Subsequent reentry into situations which rely on use of these limits is NOT authorized.") on the same page as the procedure for defogging the cockpit. [0] https://www.sr-71.org/blackbird/manual/3/3-135.php

To be fair, on the same page also there is the “taxi slowly if broken tank” failure mode, because it “can be ingested by an inlet”.

For those who don’t have the picture in mind, the first DC-3’s fuel valve was next to the air inlet. One day the operator didn’t watch the refill (They didn’t have autostop valves at the time), the fuel overflowed into the inlet, which certainly mixed it studiously with the air and pulverized the whole into the cabin. Man, aviation was wild at its beginnings.

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