Is the SR-71 considered a stealth aircraft?

Вероятность обнаружения падает с ростом ЭПР?! Где ты взял эту потешную мурзилку?!

ENG: Detection probability decrease with RCS increase?! Where you have taken this funny pic?!

Maybe it’s probability of not being detected.

As said SR-71 had fairly large RCS and by that, was not particularly challenging aircraft to track. However, its speed was a complication. With their low pulse frequency, surveilance radars tended to ignore Mach 3 target as echo’s position changed so much between the pulses. A Finnish radar operator said in an interview during the ’90s “It took some time to learn to track SR-71. If Mach 6 Aurora really existed, it couldn’t be tracked with current surveilance radars”.

But surely modern radars can track things going faster than Mach 6, otherwise how do they intercept BMs?

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Integral characteristics effective area reflecting of target. effective area reflecting / эффективная площадь рассеивания (ЭПР) – RCS

Вероятность обнаружения падает с ростом ЭПР?! Где ты взял эту потешную мурзилку?!

ENG: Detection probability decrease with RCS increase?! Where you have taken this funny pic?!

As said SR-71 had fairly large RCS and by that, was not particularly challenging aircraft to track. However, its speed was a complication. With their low pulse frequency, surveilance radars tended to ignore Mach 3 target as echo’s position changed so much between the pulses. A Finnish radar operator said in an interview during the ’90s “It took some time to learn to track SR-71. If Mach 6 Aurora really existed, it couldn’t be tracked with current surveilance radars”.

So what crashed at Boscombe Down in 1994? That’s the $1 million dollar question.

Funny to see a landing gear fitted on that cgi…

B/w the A11 was a non stealth aircraft
The A12 was.
Obviously, with the time technology has outpaced its signature reduction efforts but still the intends (and results) were there.

One day we might learn all about the a12. I am sure there is still plenty to let us stunned.

The number put by Andraxxus doesn’t seem incoherent. Taking the rcs of a comparatively sized aircraft of the same era will put you well above this as was already said. And during those baltic mission, the name of the game was to be seen (and remain out of reach by sheer speed).

Whose design was the Kingfish ?

At the time it was General Dynamics Fort Worth. Now Lockheed Martin Fort Worth.

Whose design was the Kingfish ?

Is it better to talk about the survivability of the aircraft in the first ten years of operation rather than decades after it was revealed and understood by the opposition?

How well did the SR-71perform in the 60s and early 70s rather than some years before its retirement?

Here is Kingfish by the way:

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…and that is the design which lost the competition!

None claimed the SR-71 could not be tracked during its typical “Baltic Express Run”. No ECM in use by the SR-71 and it stayed outside national boundaries using its side-looking sensors high up- The ones tracking are on alert if the SR-71 may diverting from its assumed track.

http://www.airsceneuk.org.uk/oldstuff/2006/sr71/sr71.htm

Have you read the heaadline/topic?

It is “Is the SR-71 considered a stealth aircraft?”. I dropped actual footage from radar tracking using the radars of the same era (radars from 1966, used in the 1980’s).

It had lower RCS than many other aircraft (as can be seen in the radar footage) but I would be reluctant to answer the OP that the SR-71 could be considered stealthy.

Regarding the ECM, there is footage of ECM-use as well in the vid. ECM at that time was mostly white noise and barrage… and it wouldn’t add to the stealthiness.

It had reduced RCS compared to many contemporary fighters, however radars at the time where able to pick up the SR71 at max range (+400 km in some cases) and it was designed to be stealthy. F117 was the first actual stealth jet outside of the likes of skunk works.

Some examples of tracking from an old thread:

Sample track points from the vid.

Tracked with “This one (PS-66) had a signal enhancement of 10dB compared to noise, 10 years later, 1975/1977 signal processing in the Giraffe had improved to >40dB over noise level. (the year is wrong in my pic, radar is from 1966, hence the name. PS-66)”

So there was no problem tracking the SR71 with radar systems anno 1966.

//Tu22m

None claimed the SR-71 could not be tracked during its typical “Baltic Express Run”. No ECM in use by the SR-71 and it stayed outside national boundaries using its side-looking sensors high up- The ones tracking are on alert if the SR-71 may diverting from its assumed track.

http://www.airsceneuk.org.uk/oldstuff/2006/sr71/sr71.htm

It had reduced RCS compared to many contemporary fighters, however radars at the time where able to pick up the SR71 at max range (+400 km in some cases) and it was designed to be stealthy. F117 was the first actual stealth jet outside of the likes of skunk works.

Some examples of tracking from an old thread:

All videos are from outside Gotland, southern Sweden and the Baltic region. It is speeded up… you might need a map on the side 😉

First up PS-08 from 1955 (2:00 –>)

5:40 Chaffs from Tu-16, 1962. 7 strakes outside of Ösel.
6:40 1965 Polish/German war excercise, total 200 ac, Tu 16 jamming and releasing chaffs. Coming from east. Chaffs released together with jamming during egress after “successful attack”.

PS-65 from 1965 9:00–>
1968 10:40 Soviet drops troops in Chechoslovakia, the colons in south heading north east are returning aircrafts. Center of radar Blekinge (or Skåne) Sweden.
12:00 Krivak Mutiny outside of Riga and how the air forces reacted. The flashing numbers are altitude measurements. Possibly in 100s of meters.
17:00 Fake attack 1980, Backfires coming in from south east. What a small attack from startegic bombers look like without EW support.
19:50 1984, Incident breach of airspace + jamming and chaff releases. Radar located at Gotland. Jamming caused anomalies making the coast of Baltikum show on the screens. 21:00 the Plot of how the Russian aircrafts moved. In 20:10 you will see heavy EW.

PS-66 from 1970 –> 24:20
27:00 SR71 1980 (quick flash at Bornholm, 27:53. 27:58 it is between Latvia and Gotland, makes a sharp left turn and passes between Öland and Gotland in 28:06
30:00 1987, SR71 photographed by two Viggens after the SR71 lost power in right engine. SR71 comes in the same way (south, and really really fast), you will see two dots come in after the break take some pictures and then return back.

32:11 statistics of breach of airspace and by who. 32:40, blue dots, visual confirmation of NATO aircrafts, red dots WP during one year.

I hope this can clarify at what ranges targets at altitude can be tracked as well as how jamming, chaff releases etc affect the performance of the tracking.

Interesting to note: SR71 was tracked as far out as 400km (Olofström -> the Baltic airspace).

Sample track points from the vid.

Tracked with “This one (PS-66) had a signal enhancement of 10dB compared to noise, 10 years later, 1975/1977 signal processing in the Giraffe had improved to >40dB over noise level. (the year is wrong in my pic, radar is from 1966, hence the name. PS-66)”

So there was no problem tracking the SR71 with radar systems anno 1966.

//Tu22m

Those tests took place in the mid-1960s. If the A-11, A-12, and SR-71 were not intended to be stealthy, then why spend the money on RCS testing?

I thinks it’s a semantics issue. The term “stealth aircraft” didn’t come about until the 80s or 90s. Certainly the Skunk Works was trying to reduce the radar return (RCS) to improve operating characteristics, thus the testing and efforts to measure and reduce the RCS. But the term “stealth” hadn’t been invented (or popularized) by the media yet. So, first aircraft to be specifically designed to reduce RCS? Yes. First to be called a stealth aircraft? No, because the media hadn’t made up the term as a public “nom de jour”.

Google “SR-71 RCS test picture”

Those tests took place in the mid-1960s. If the A-11, A-12, and SR-71 were not intended to be stealthy, then why spend the money on RCS testing?

General Dynamics’ Kingfish vehicle was in competition for the Oxcart contract. Kingfish was a development of GD’s Fish LO airplane. Kingfish lost the competition to Lockheed’s airplane.

The SR-71 certainly had design features intended to reduce its radar signature, including chines, canted tails, RAM at leading/trailing edges, and a number of others.

That radar systems could still detect it doesn’t mean it wasn’t stealthy — stealth just reduces the range at which you can be detected, tracked, shot at, etc. Given that the SR-71 was never shot down, I guess you can say the stealth was successful, although it’s more due to a combination of stealth, height, and speed, not stealth alone. It really depends on what you mean by “stealth aircraft”. You might call it first generation stealth if you want.

P(обнаружения) – “вероятность обнаружения” – probability of detection, IMHO

Can’t be, it gets higher for lower RCS.

Radar contact established unknown radar. On the “Kola Peninsula”, a lot of them. All ships have a “post air defense alert.” When the flying enemy, its coordinates transmitted Morse code. The operator draws the flight path on the tablet. I served on the destroyer “Flawless” (“Безупречный”, проект 956)

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What’s at the Y axis ? Frequency ?

P(обнаружения) – “вероятность обнаружения” – probability of detection, IMHO

For those interested, here is a good read on the SR-71 design evolution and RCS reduction:
http://enu.kz/repository/2009/AIAA-2009-1522.pdf

Detecting and tracking the SR-71 is not difficult for the Soviet anti-air defense. I’ve heard about it many times during my service on the destroyer (1989 – 1990 year).
Score RCS – 6.8 m2

https://www.youtube.com/watch?feature=player_embedded&v=rAUodXI4LPw#t=1621

… and never got an idea how it is masked by the own ECM.
“The SR-71 program’s main operational capabilities came to a close at the end of fiscal year 1989 (October 1989). The 1st SRS kept its pilots and aircraft operational and active, and flew a limited number of operational reconnaissance missions through the end of 1989 and into 1990, due to uncertainty over the timing of the final termination of funding for the program. The squadron finally closed in mid-1990, and the aircraft were distributed to static display locations, with a number kept in reserve storage.”
The name of the destroyer will be helpfull to verify, if there was a radar contact at all at that time-scale at the end of the Cold War.