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Did the SR-71 evade detection? I was under the (perhaps wrongful) impression that it just outran the consequences of detection.

by ouid 6y ago

the-dude 6y ago
I was under the impression it flew too high to be reached by surface to air missiles.
eximius 6y ago
It's stealth was fairly advanced for the time. It was a bit of both.
classichasclass 6y ago
That's pretty much it. The standard countermeasure for launch detection was simply to accelerate and outrun the missile. It had some early stealth attributes but could still be detected by the systems of the time.
- sidewndr46 6y ago
  What "early stealth" did it have? The most I've heard from pilots is that they didn't use an airborne radar and didn't use the VHF radio on the plane under any circumstance. Even on the runway, it was forbidden. Those things have nothing to do with stealth and everything to do with basic signals intelligence stuff.
  - ForHackernews 6y ago
    According to wikipedia [0] > The second operational aircraft[40] designed around a stealth aircraft shape and materials, after the Lockheed A-12,[40] the SR-71 had several features designed to reduce its radar signature. The SR-71 had a radar cross-section (RCS) around 110 sq ft (10 m2).[41] Drawing on early studies in radar stealth technology, which indicated that a shape with flattened, tapering sides would reflect most energy away from a radar beam's place of origin, engineers added chines and canted the vertical control surfaces inward. Special radar-absorbing materials were incorporated into sawtooth-shaped sections of the aircraft's skin. Cesium-based fuel additives were used to somewhat reduce exhaust plumes visibility to radar, although exhaust streams remained quite apparent. Kelly Johnson later conceded that Soviet radar technology advanced faster than the stealth technology employed against it.[42] [0] https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Shape_and_threat_avoidance https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Shape...
    - JumpCrisscross 6y ago
      > Cesium-based fuel additives Oh god, I never thought about all the awful additives militaries must add to their fuels and lubricants and other industrial chemicals.
      - sidewndr46 6y ago
        Go read up on zip fuels if you want to learn about truly strange stuff. Those were just tested however, never actually used for production aircraft.

Did the SR-71 evade detection? I was under the (perhaps wrongful) impression that it just outran the consequences of detection.

by ouid 6y ago

Did the SR-71 evade detection? I was under the (perhaps wrongful) impression that it just outran the consequences of detection.

the-dude 6y ago

I was under the impression it flew too high to be reached by surface to air missiles.

eximius 6y ago

It's stealth was fairly advanced for the time. It was a bit of both.

classichasclass 6y ago

That's pretty much it. The standard countermeasure for launch detection was simply to accelerate and outrun the missile. It had some early stealth attributes but could still be detected by the systems of the time.

sidewndr46 6y ago
What "early stealth" did it have? The most I've heard from pilots is that they didn't use an airborne radar and didn't use the VHF radio on the plane under any circumstance. Even on the runway, it was forbidden. Those things have nothing to do with stealth and everything to do with basic signals intelligence stuff.
- ForHackernews 6y ago
  According to wikipedia [0] > The second operational aircraft[40] designed around a stealth aircraft shape and materials, after the Lockheed A-12,[40] the SR-71 had several features designed to reduce its radar signature. The SR-71 had a radar cross-section (RCS) around 110 sq ft (10 m2).[41] Drawing on early studies in radar stealth technology, which indicated that a shape with flattened, tapering sides would reflect most energy away from a radar beam's place of origin, engineers added chines and canted the vertical control surfaces inward. Special radar-absorbing materials were incorporated into sawtooth-shaped sections of the aircraft's skin. Cesium-based fuel additives were used to somewhat reduce exhaust plumes visibility to radar, although exhaust streams remained quite apparent. Kelly Johnson later conceded that Soviet radar technology advanced faster than the stealth technology employed against it.[42] [0] https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Shape_and_threat_avoidance https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird#Shape...
  - JumpCrisscross 6y ago
    > Cesium-based fuel additives Oh god, I never thought about all the awful additives militaries must add to their fuels and lubricants and other industrial chemicals.
    - sidewndr46 6y ago
      Go read up on zip fuels if you want to learn about truly strange stuff. Those were just tested however, never actually used for production aircraft.