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Thread: Beyond the SR-71

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    Registered User Victor Bravo's Avatar
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    Re: Beyond the SR-71

    Quote Originally Posted by bmcj View Post
    I would imagine the true limiting factor would be if the shock cone narrowed enough to expose the rudders and engine inlets to freestream air.
    Not the ability to shed or deal with heat?

    Funny how we're still discussing the classified secrets of the SR-71, which is now a 50+ year old aircraft. That, and with the B-52 design soldiering on for more and more years, and the B-52 is now a 60 year old airplane design.... I"m guessing there's a bunch of really old (or passed on) engineers who are laughing their asses off right about now because their work way back in the slide rule days has set the bar pretty darn high.
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    Re: Beyond the SR-71

    Quote Originally Posted by Wanttaja View Post
    Drones and manned aircraft are limited by political and practical limitations.
    Tidbit of trivia from a SR-71 driver's Oshkosh presentation: The SR-71 never flew over the USSR due to fear, by the presidents, of a repeat of the Gary Powers shoot down.

    "The most beautiful sight in orbit is a urine dump at sunset" - Rusty Schweickart, Apollo 9.
    Shortly after his Apollo flight, Rusty was a guest speaker in one of my classes. The first question that he got, from one of the three female students, was, "How do you [poop] in space?"


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    Registered User gtae07's Avatar
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    Re: Beyond the SR-71

    Quote Originally Posted by Victor Bravo View Post
    Not the ability to shed or deal with heat?

    Funny how we're still discussing the classified secrets of the SR-71, which is now a 50+ year old aircraft. That, and with the B-52 design soldiering on for more and more years, and the B-52 is now a 60 year old airplane design.... I"m guessing there's a bunch of really old (or passed on) engineers who are laughing their asses off right about now because their work way back in the slide rule days has set the bar pretty darn high.
    The B-52, at least, soldiers on not because it's so great and wonderful that we can't match the engineering, but because nobody wants to cough up enough money at one time to replace them. Instead, we piecemeal them with upgrades and refurbishments and repairs.

    We could do the SR-71 again, but it would cost ten times as much (after inflation adjustment) and would take four times as long. We aren't as risk-tolerant today, our design processes are much more bureaucratic, the aircraft itself would be great (easier to fly, easier to maintain, etc.), and the whole thing would be known about from day one.


    Quote Originally Posted by Aerowerx View Post
    The problem with satellites is that you have to wait for the next one to pass over your target area, and then it may be in range for 15-20 minutes (just guessing, folks!).
    Less time than that. More along the lines of 5 minutes, really.

    But the biggest problem with a satellite (besides weather cover) is that everyone else knows where they are. If you know where your opponent's satellites are, you know when you'll be visible to them, and you can hide things. This was done routinely in the cold war--pull your secret test aircraft into the hangar before the satellite pass so it isn't seen.
    I reserve the right to be smarter tomorrow than I was yesterday.

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    Registered User Tiger Tim's Avatar
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    Re: Beyond the SR-71

    Quote Originally Posted by bmcj View Post
    From a reliable source, the SR-71 is capable of more speed and altitude. The engines gain thrust as speed increases, but the restricting conditions is that the shock cone from the long nose narrows with increasing speed and starts to expose the wingtips to freestream velocity at (I don't recall if it was M3.2 or M3.5). Lockheed told the Air Force that it could fly faster, it that they (the Air Force) would be the test pilots for the higher speeds and would do so at their own risk.

    I would imagine the true limiting factor would be if the shock cone narrowed enough to expose the rudders and engine inlets to freestream air.
    I found a POH for the SR-71 online once. I have no idea how current it was (probably obsolete in a few areas) but as I've seen more than a couple old technical manuals this one sure seemed like the real deal. Anyways, my favourite part was the line in limitations that read something like, "Maximum speed Mach 3.1, higher speeds are attainable only under direct order from the Commander in Chief."

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    Re: Beyond the SR-71

    Kyle,

    I'd consider "spilling it" but he was a nice guy and if I did it might cause him problems as I believe he still works there. I will say it was a bit traumatic for him as he was the sole "virgin" in his unit and his personal ethics required he report his goof. He felt he would suffer greatly. Spoke with him a few times after that, but the point was never revisited.

    I still have great respect for the man.

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    Re: Beyond the SR-71

    Gary Powers is the reason for the SR-71. The minute his U-2 got shot down, the A-12 became obsolete. Escalation was the A-12s biggest flaw. Russians have a need to make better missiles or their own A-12 like plane. The SR-71 took that out with the side looking equipment, which kept it out of Russian airspace. Diplomatic move vs a technology one. Diplomatic also changing service ownership. Same as putting weapons on one, killing the YF-12 kept escalation potential of Russians having Mach 3 bomber overflying the US like we would be doing to them. Much better have them keep their Bears and us use the B-52. B1 and B2 except for money are forgotten on purpose. Money, too, got scarce. Killed Apollo with 2 ready rockets, 1/2 of another.
    Not that no one can follow the X-37B orbit, but has to be the best spy satellite we can put up equipment wise, low altitude and it has a short mission fuel supply compared to normal satellites, but because the craft can be returned, the fuel can be used with abandon for maneuvering. It also provides an escape for the equipment, de orbit. I think mostly it flies in wait, loitering, for something big to happen and we dont know how maneuverable it is in space compared to conventional satellites.

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    Re: Beyond the SR-71

    Quote Originally Posted by gtae07 View Post
    The B-52, at least, soldiers on not because it's so great and wonderful that we can't match the engineering, but because nobody wants to cough up enough money at one time to replace them. Instead, we piecemeal them with upgrades and refurbishments and repairs.
    It's design role -- dropping nuclear bombs -- was taken over by ICBMs and SLBMs, both of which are likely to be much better at it. It's main mission -- dropping masses of bombs on ill-defended troops -- could be done by B-17s.

    Quote Originally Posted by gtae07 View Post
    We could do the SR-71 again, but it would cost ten times as much (after inflation adjustment) and would take four times as long. We aren't as risk-tolerant today, our design processes are much more bureaucratic, the aircraft itself would be great (easier to fly, easier to maintain, etc.), and the whole thing would be known about from day one.
    A major -- perhaps the major reason -- the SR-71 project worked so well was that Lockheed was given a very well-defined set of goals (although the associated YF-12 was canceled because its weapon system failed). While I think that there are a lot of problems with the procurement process, I think the main one is that so much expertise has been outsourced that the people writing the specs can't tell the state of the art from movie special effects.

    Quote Originally Posted by gtae07 View Post
    Less time than that. More along the lines of 5 minutes, really.

    But the biggest problem with a satellite (besides weather cover) is that everyone else knows where they are. If you know where your opponent's satellites are, you know when you'll be visible to them, and you can hide things. This was done routinely in the cold war--pull your secret test aircraft into the hangar before the satellite pass so it isn't seen.
    Despite that, the satellites did catch quite a few secret aircraft on the ground, at the Soviet equivalent of Edwards. Do also remember that satellite orbits can be changed, albeit with difficulty, and that there can be multiple satellites. There are also, I think, elint satellites in geosynchronous orbit. There are also a lot of satellites, and one cannot be absolutely sure which of those satellites crossing one's sky are NRO spy satellites, something like the French SPOT satellite, some random cubesat, an ally's communications satellite, ...., (as an aside, a Vela satellite caught a gamma ray event from apartheid-era South Africa. The explanation was "meteor," but I suspect it was either a SA or Israeli nuclear test; the Vela satellites were kept pretty secret until they started getting false positives, which turned out to be astronomical events: gamma ray bursts, but those were captured by multiple satellites simultaneously, not by a single satellite, as happened over SA).

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    Registered User Wanttaja's Avatar
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    Re: Beyond the SR-71

    Quote Originally Posted by gtae07 View Post
    But the biggest problem with a satellite (besides weather cover) is that everyone else knows where they are. If you know where your opponent's satellites are, you know when you'll be visible to them, and you can hide things. This was done routinely in the cold war--pull your secret test aircraft into the hangar before the satellite pass so it isn't seen.
    Denial and Deception are always factors in intelligence collection, whether space-based or air breathing. But, as you mention, the orbital elements of spacecraft are fairly fixed, and thus the times they come overheard are predictable.

    However, as Swampyankee says, satellites can maneuver to some extent. Not to the degree HOLLYWOOD thinks, of course, but in a lot of cases, your target nations aren't that sophisticated. It may take days or even weeks for them to realize their times are off.

    Another factor is the absolute proliferation of imaging satellites. There are a lot of civilian cameras out there, and trying to dodge them all is difficult. It's getting worse, too...there are outfits that have launched cameras on Cubesats, which can be as small as four inches.

    And, of course, there are things that CAN'T be hid. The Chinese buildup in the Spratly Islands is a good example, preparation for a space launch or missile test is another.

    Ron Wanttaja

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    Re: Beyond the SR-71

    Quote Originally Posted by Swampyankee View Post


    A major -- perhaps the major reason -- the SR-71 project worked so well was that Lockheed was given a very well-defined set of goals (although the associated YF-12 was canceled because its weapon system failed).

    Do also remember that satellite orbits can be changed, albeit with difficulty, and that there can be multiple satellites. There are also, I think, elint satellites in geosynchronous orbit. There are also a lot of satellites, and one cannot be absolutely sure which of those satellites crossing one's sky are NRO spy satellites, something like the French SPOT satellite, some random cubesat, an ally's communications satellite,
    As you say, the SR was developed as a single point airplane and the goal never changed. Also, Lockheed was given free reign to take care of its business. That makes things much simpler than a protracted set of requirements, designs, re-definition of the mission, redesign, etc.

    The other thing about satellites is there are stealthy satellites. No telling how hard they are to track, but I suspect they give you a better opportunity to change orbits and get in a few surprise passes.

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    Re: Beyond the SR-71

    The problem with the YF-12 was not the weapon system. That went on to become the F-14's Phoenix. The problem was it took too long to launch to be a credible interceptor. The seldom heard of Bomber version of the YF-12 was cancelled because ICBM's made it not needed. ( see SRAM missiles used by the B-52 & B-1, luckily, never in anger )

    The A-12 was a fine plane but they wanted more & bigger camera/sensor bays. Thus the SR-71. ( who's name was misread by LBJ at the press conference so they retroactively changed the name to fit the President's goof. )

    No one really knows the top speed of the Blackbird. Probably. Maybe. It would keep accelerating unless you throttled back... a little bit. ( Important that it be a little bit.... more and the engine would drag on the mounts then"unstart". Military doublespeak is sometimes funny... )

    "Aurora" was a cover program for funding for Lockheed. The money actually went to the Sea Shadow test boat/ship. https://en.wikipedia.org/wiki/Sea_Shadow_(IX-529) Someone noticed a bunchaton of money going to Lockheed for black projects and the Blackbird replacement was the cover story.

    What the "rings on a rope" pulse combustion? test plane and the other hypersonic test planes were? I don't know. Seriously.

    The "constellation camouflage" idea for a craft that never went into production, I did "hear" about. Lights on the bottom side of the wing are programmed to go backwards at flight speed so the aircraft eclipsing the stars was very hard to see. For a more advanced version of that see the Novel "The Ransom Of Black Stealth One" by Dean Ing.

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    Re: Beyond the SR-71

    Quote Originally Posted by Kyle Boatright View Post
    The other thing about satellites is there are stealthy satellites. No telling how hard they are to track, but I suspect they give you a better opportunity to change orbits and get in a few surprise passes.
    I know that the USAF has ground-based cameras that can see satellites as small as a basketball.
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    Re: Beyond the SR-71

    Quote Originally Posted by Tiger Tim View Post
    .... "Maximum speed Mach 3.1, higher speeds are attainable only under direct order from the Commander in Chief."
    An anecdotal story my brother told me.

    When he was a USAF pilot, they were monitoring some ATC on a military frequency, and over heard something like this...

    "Air Force xyz, what is your altitude?"

    "Above flight level 600"

    "Air Force xyz, what is your altitude?"

    "Above 600"

    "Air Force xyz, what is your altitude!?"

    "Mister, you ain't supposed to know my altitude!!"

    At that time in history, the only thing the USAF had that regularly flew above FL600 was the SR-71.
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    Re: Beyond the SR-71

    Quote Originally Posted by Aerowerx View Post
    An anecdotal story my brother told me.

    When he was a USAF pilot, they were monitoring some ATC on a military frequency, and over heard something like this...

    "Air Force xyz, what is your altitude?"

    "Above flight level 600"

    "Air Force xyz, what is your altitude?"

    "Above 600"

    "Air Force xyz, what is your altitude!?"

    "Mister, you ain't supposed to know my altitude!!"

    At that time in history, the only thing the USAF had that regularly flew above FL600 was the SR-71.
    The U-2 could cruise in that neighborhood, albeit with something like a 2 knot distance between stall and buffet.

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    Re: Beyond the SR-71

    Quote Originally Posted by Aerowerx View Post
    I know that the USAF has ground-based cameras that can see satellites as small as a basketball.
    First, you have to find it using radar and plot its orbit. Then you can take a peek with a camera. How many of our adversaries or potential adversaries can do that against a stealthy satellite?

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    Re: Beyond the SR-71

    Quote Originally Posted by Aesquire View Post
    No one really knows the top speed of the Blackbird. Probably. Maybe. It would keep accelerating unless you throttled back... a little bit. ( Important that it be a little bit.... more and the engine would drag on the mounts then"unstart". Military doublespeak is sometimes funny... )

    What the "rings on a rope" pulse combustion? test plane and the other hypersonic test planes were? I don't know. Seriously.
    You can find credible sources giving the top (tested) speed of the SR-71 of M3.5, and M3.7 for the A-12.

    I've seen "doughnuts on a rope" looking contrails from airliners. Not sure what vortexes create them, but they are not necessarily tied to anything special.

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