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Blackbird SR-71 Flight Manual (2010)

sr-71.org

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Re: Blackbird SR-71 Flight Manual (2010)

#141

Post by masklinn »

alexis_fr wrote: post #95
jedberg wrote: post #6

The maintenance manual is a fun read too. A lot of the repair procedures end with PTF. That means “Pound to Fit” (with a hammer or mallet). The panels flexed so much that they would come back a different shape than they were manufactured and had to be hammered into place.

Why were instruments (instruments? or panels?) so flexible? Was ut to sustain altitude, pressure, G and speed?

> Was ut to sustain altitude, pressure, G and speed?

Heat expansion. That's also why it would leak fuel when on the ground (fuel lines would expand at speed so they needed expansion gaps when on the ground).

Outside emergency situation, the crew had to wait inside the plane after landing, waiting for the surfaces to cool down enough that they could safely get out without melting their gear.

Re: Blackbird SR-71 Flight Manual (2010)

#142

Post by ptha »

trhway wrote: post #126
yutyut wrote: post #86

Earlier quoted context omitted.

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).

>Granted, a hydraulic failure of two redundant and independent systems is astronomically unlikely (and the outcome will almost certainly be fatal). Triple system failure https://en.m.wikipedia.org/wiki/United_Airlines_Flight_232 “The crew contacted United maintenance personnel via radio, but were told that, as a total loss of hydraulics on the DC-10 was considered "virtually impossible", there were no established pro…

Fascinating/harrowing stuff: Despite these losses, the crew was able to attain and then maintain limited control by using the throttles to adjust thrust to the remaining wing-mounted engines. By using each engine independently, the crew made rough steering adjustments, and by using the engines together they were able to roughly adjust altitude.

With no control surfaces, and using the engine thrust they attempted a landing - of the 296 people on board, 111 died.

Re: Blackbird SR-71 Flight Manual (2010)

#143

Post by village-idiot »

kryogen1c wrote: post #71
wolfgang42 wrote: post #54

Earlier quoted context omitted.

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

Nuclear propulsion manuals for the U.S. navy have similar wordings. >By order of the commanding officer [actually a highranking person on carriers, compared to little ships where COs can be realtively junior and low ranking], this reactor limit may be ignored during tactical situations. Legend has it that every CO (3, i think i heard) to invoke "when tactical" exceptions have been fired in the following review. The o…

When’s the last time a large US navy vessel was in a situation where exceeding limits was justifiable due to tactical needs? I’d probably wager that WW2 was the last time.

Re: Blackbird SR-71 Flight Manual (2010)

#144

Post by ubermonkey »

cladari wrote: post #115
kryogen1c wrote: post #71

Earlier quoted context omitted.

Nuclear propulsion manuals for the U.S. navy have similar wordings. >By order of the commanding officer [actually a highranking person on carriers, compared to little ships where COs can be realtively junior and low ranking], this reactor limit may be ignored during tactical situations. Legend has it that every CO (3, i think i heard) to invoke "when tactical" exceptions have been fired in the following review. The o…

I'm remembering back 40 years here. I worked in the engine room of a nuclear powered cruiser. We had a switch called something like "battle bypass" that would bypass all the auto scram functions. The military calls a shutdown scram while the commercial industry calls it trip. We had a captain rank captain and I believe all nuclear powered vessels had one.

I love the qualifying phrase "captain rank captain."

(And I understand why it's needed.)

Re: Blackbird SR-71 Flight Manual (2010)

#145

Post by joncrane »

duxup wrote: post #26
codr7 wrote: 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

My favorite part is

>Officials are trying to determine how to remove the plane from its perch and warned people to stay away from it.

Re: Blackbird SR-71 Flight Manual (2010)

#146

Post by nradov »

trhway wrote: post #126
yutyut wrote: post #86

Earlier quoted context omitted.

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).

>Granted, a hydraulic failure of two redundant and independent systems is astronomically unlikely (and the outcome will almost certainly be fatal). Triple system failure https://en.m.wikipedia.org/wiki/United_Airlines_Flight_232 “The crew contacted United maintenance personnel via radio, but were told that, as a total loss of hydraulics on the DC-10 was considered "virtually impossible", there were no established pro…

Cases like that one are the reason that passenger aircraft won't be fully automated any time soon. Autopilots are unable to cope with unexpected system failures.

Re: Blackbird SR-71 Flight Manual (2010)

#147

Post by golergka »

knute wrote: post #36
collinf wrote: post #31

Posting this here hoping that someone with more knowledge can enlighten me about this. After going down a bit of the rabbit hole, I see that the SR-71's first flight was in 1964. It has held the record for fastest air-breathing manned aircraft[0] since 1976. What is the reason that given all of the technological advances that record hasn't been broken? [0] https://en.wikipedia.org/wiki/Flight_airspeed_record

There are faster air-breathing aircraft (e.g. [0]), but none of them are manned because with modern technology there's no need to put a person in them, and the people funding these developments aren't interested in spending lots of money just to chase records. There's also the outside possibility that faster manned aircraft exist, but remain classified [1]. [0] https://en.wikipedia.org/wiki/Boeing_X-51_Waverider [1]…

I just love how this super-hightech, experimental military aircraft has parts secured with duct tape in this Wikipedia photo: https://upload.wikimedia.org/wikipedia/commons/thumb/e/e5/X-...

Re: Blackbird SR-71 Flight Manual (2010)

#148

Post by nradov »

walrus01 wrote: post #106
village-idiot wrote: post #69

Earlier quoted context omitted.

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…

Based on the totally amateur knowledge level of someone that once spent a few hours researching stealth satellites (MISTY, etc), there's obviously a demand within the NRO for satellites that can be launched into a known orbit, with published two line elements, and then go stealthy and change their orbit into something which cannot be predicted by enemy nation-state ground forces. I don't believe anything worthwhile a…

There's no way to really "go stealthy" in space. If a satellite is operational then it has to emit enough heat to be clearly visible to IR sensors.

http://www.projectrho.com/public_html/rocket/spacewardetect....

Re: Blackbird SR-71 Flight Manual (2010)

#149

Post by danaliv »

kbenson wrote: post #122
danaliv wrote: post #104

Earlier quoted context omitted.

I flew an L-39 with inoperative ejection rockets. The bailout procedure was: 1. Roll inverted. 2. Trim full nose down. (Down = skyward at this point.) 3. Blow canopy. 4. Fall out.

So... What do you suppose the chance is you would have hit the tail fin?

Less than the chance of the original emergency killing you!

That’s what the full trim is for. It makes the aircraft pitch away once you let go of the stick.

Re: Blackbird SR-71 Flight Manual (2010)

#150

Post by danaliv »

mongol wrote: post #128
danaliv wrote: post #104

Earlier quoted context omitted.

I flew an L-39 with inoperative ejection rockets. The bailout procedure was: 1. Roll inverted. 2. Trim full nose down. (Down = skyward at this point.) 3. Blow canopy. 4. Fall out.

What about seatbelts?

Depends on whether your parachute is integral to the seat or you’re wearing a pack. If the chute is in the seat, I would highly recommend staying harnessed to it.
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