What Interceptor or Fighter Can Stop the SR-71?

Actually thats not what I was arguing at all, you can never say never.

I was arguing this post, which, as you can see, suggests such capability may ALREADY exist.

Originally posted by BigTrain
Stealth does not have to be slow and low. Whats to say that they havent developed a stealth hypersonic aircraft. The im sure they could develop a way to make a hypersonic plane stealthy, almost invisible.

Train

[edit on 27-10-2005 by waynos]

Its sad to say that I think nobody but waynos and I are still on this thread. I think its dead. Maybe hypersonic aircraft exist, maybe, maybe not. We dont know.

Train

A X-43A turned missile could intercept an SR-71. Launched from a plane attached to a rocket to take it to Mach 3+ the it can accelerate up to Mach 10.

More than 3 time the speed of the SR-71 and once it got near enough it could detonate itself.

It think is the only known aircraft that could actually do it...

So an scram-jet missile is the answer

That's my 2 cents

Originally posted by carcharodon
A X-43A turned missile could intercept an SR-71. Launched from a plane attached to a rocket to take it to Mach 3+ the it can accelerate up to Mach 10.

More than 3 time the speed of the SR-71 and once it got near enough it could detonate itself.

It think is the only known aircraft that could actually do it...

So an scram-jet missile is the answer

That's my 2 cents

Lets install laser detection systems as well.

The X-43a is better off going in a straight line, then having to manuever after an SR-71, what I would like to know is, how much farther in advanced can you have the missile up and running?

Shattered OUT...

If an X-43 based missile was fired at a Blackbird going at mach 3 (assuming all of that is possible of course) then it would be going in a straight line anyway and would not have to manouvre at all.

Originally posted by waynos
Its nothing to do with attitude, its common sense. The first supersonic plane to fly without afterburners wasn't the F/A-22 as you might think, but the English Electric P.1 in 1954. It took half a century for technology to reach a level where the F/A-22 is one of the first group of fighters capable of the feat in normal operations.

If hypersonic stealth was at all possible then the F/A-22 and B-2 would be it, surely? If such ability has been developed. Otherwise whats the point?

Waynos, I think one of the problems with the ATF and ATB is that they were not designed to be purely hypersonic - their missions required other atributes.

The ATB needed extreme range and payload, and the ATF needed extreme agility. These things, coupled with technological limits at the time, prevented them from being considered.

I think the most telling thing is that the B-3 studies all seem to be a stealthy high supersonic-hypersonic aircraft.

Give us Yanks a few years, and we'll be raining hypersonic stealthy death from 100,000+ feet.

I agree with you there, my post was in reply to the blokes comment that such an aircraft might already have been developed in a 'for all we know' sort of way. To which I simply believe that if it really was the case then there would be no way the Raptor or B-2 (depending which mission we are on about) would ever see the operational light of day, given their own vast expense.

You may not know this but a swedish viggen fighter intercepted an sr-71 during the 80:ies and got a radarlock.

Originally posted by seecan
You may not know this but a swedish viggen fighter intercepted an sr-71 during the 80:ies and got a radarlock.

This same Viggen?

link







"Mach 2.0 (1,321 mph / 2126 km/h) at 36,000 ft (10975 m)" That speed and altitude is capable of successfully intercepting an SR-71?

"one ventral 30-mm Oerlikon KCA cannon w/ 150 rounds. Up to 6 Rb 71 Sky Flash and Rb 74 (AIM-9L) AAMs. Air-to-surface armament available."That armament is capable of successfully shooting down an SR-71.

Having a "Lock-on" and intercepting are two completely different things. Anything can lock-on with RADAR, I'm positive that the SR-71 has been locked on to by many a RADAR, but actually successfully launching a missile, or Anti-Aircraft weapon and bringing that SR-71 down to the ground, is something completely different.

And out of curiosity, with the SAAB 37 Viggen being Swedish and all, why would it need to have to lock-on to an SR-71? Unless of course it was an excersize.

Shattered OUT...

"Mach 2.0 (1,321 mph / 2126 km/h) at 36,000 ft (10975 m)" That speed and altitude is capable of successfully intercepting an SR-71?

Just want to point out that the max altitude of the Viggen is 60,000ft, the 36,000ft figure is just the altitude at which its maximum speed is achieved, in common with most other fighters.

It doesn't change the fact that what you are saying is right, 60,000 is still too low to intercept an SR-71, and a radar lock is not quite an interception is it.

And out of curiosity, with the SAAB 37 Viggen being Swedish and all, why would it need to have to lock-on to an SR-71?

Sweden is a neutral country and would treat overflights by the USA and USSR,(as was) or anybody else, with equal contempt.

A good read on the Viggen and MIG 25/31 interceptions is in Paul Crickmores LOCKHEED BLACKBIRD BEYOND THE SECRET MISSIONS.

"It doesn't change the fact that what you are saying is right, 60,000 is still too low to intercept an SR-71"

Nah - you can intercept one from zero feet altitude with the right missile.
See the comments earlier from the F-15 pilot.

OK,fair do's, correction, maybe I should have said too low to intercept it with either a Sidewinder or a Skyflash.

well i should mention that the sr-71 had some engine trouble so it had to slow down a little bit and lose som altitude, but the words of the pilot is that we reached altitudes and speeds that we never thought were possible, by the way every time there is an interception like this (QRA) the pilots take pictures of the aircraft they intercept and so is the case with this interception. Just to remind you the viggen has a JT8D engine with a localy built three stage A/B capable of producing 125KN of thrust. The speed of this A/C is mostly limited by the amount of fuel it can cary so it is a MACH 2+ A/C .

Fighter viggen JA37

Take off run: 400 m
Landing run: 450 m
Landing speed: 220 km/h
Length: 16.43 m
Span: 10.6 m
Height: 5.9 m
w folded fin: 4.0 m
Engine thrust: 7415 kp
w afterburner: 13125 kp
Range: 2000 km
Ferry range would be 2250 km, about 15-16% more with Jet A1 fuel.
Empty weight: 9500 kg
Max payload: 1700 kg
(excluding external tank)
Max take off
weight: 18600 kg
Max speed
low altitude: Mach 1.2
high altitude: Mach 2+
Guaranteed speed
high altitude: Mach 1.8
Time from brake release to 10 km or Mach 1 at low altitude: 100 s
Max altitude: 18000 m


[edit on 6-11-2005 by seecan]

Seecan, I think that with enough fuel, any Aircraft can run forever.

O, and Waynos, yea, but you see, when I first posted that bit of information I asked myself "Wait a second, 36,000 can't be right, but then I thought another thing, 36,000 is the altitude required for max speed possible. So at its fastest, the Viggen is way too slow and too low to even be able to get a sidewinder at the right range."

Yea, the armaments is one of the most important factors for shooting down aircraft, you don't necessarily see an Sa-2 on a fighter jet now do you?

Shattered OUT...

Hi guys, I´d like to contribute with a brief translation of an article posted in the official magazine from the swedish armed forces, called "insats & försvar".

The article presents an interview with the former Viggen division leader, Per-Olof Eldh. The article is about near encounters with the sr-71 blackbird near swedish airspace. He recalls one time as they where practicing airdefense over gotland (an island outside the eastcoast of sweden) but suddenly where interupted by the command central to intercept a target moving towards them, coming from the near costal area south of stockholm. Per-Olof was guided to an directattack at a target flying at 21500 meters. His radar locked on at maximum distance,and the primary weapon selected was the rb 71 skyflash, and by the numbers presented to him he knew that it could only be a mig 25 or the sr-71. As the contct came closer he could eventually see the gray siluette of an sr-71 passing a couple of 1000 meters above. Per-Olofs altitude is claimed to still be classified. But he says that he was higher then he had ever been before, and the sky turned black instead of the usual blueish colour. Since that day they had several contacts with the sr-71. They often flew very close to swedish airspace. coming from the east just south of åland at mach 3, decreasing speed to mach 2.56 to make the turn and head south along the swedish coast, accelerating between the islands gotland and öland. Per-olof says that he made 5 encounters during his time as an active pilot.

The usual way to make an intercept was to climb up to 8000 meter, turn around and head north back towards stockholm, accelerating to maximum speed and altitude. The later evaluations told them that they would have succeded in shooting down the aircraft if they had used their missiles.

My conclusion: Dont underestimate the viggen, the official performance data is probably not that correct.

Regards Eric

[edit on 16-12-2005 by Iqbad]

The SR-71 must have had so much fun toying with the swedes, lowering down to a resonable altitude, closing at mach 3, slowing to mach 2.5, just to let the pilots get alittle happy, and then rocketing away at mach 3.2+ 100,000 feet saying, catch this!!

Train

The F-15 'rule of thumb' for the MiG-25R intercept profile was-

"Clean up, sprint up, ramp up!" with the AIM-7 coming off as the jet hung, nose high, on the edge of a stall at around 1.89 and 50-60K. Whether or not you could get the SARH flyout (maintained dish point) interval afterwards before flameout bunny hopping over the top is not made clear but the pilot said that the only real assumption that could be made workable was if the Foxbat was either a radiobombing (LORAN equivalent) direct attack or photorecce run which required overflight.

Because then the Eagles could stagger back multiple offset shooter-eyeball teams (the shooter zooms-passive) and hope to get the MiG-25 to slow up (in a relative closure sense) as it 'deflected' off any contrail sightings as much as RWR detections of obstacles in it's direct objective ground track.

They could never catch the 'Bat-D if it used standoff SLAR or ELINT systems.

The SR-71 is roughly similar to the MiG-25 in that 'Warp 9' was rarely if ever used, both because of serious, never resolved, problems with fuel efficiencies for range and some /nasty/ (especially in the first two decades of use before the digital integrated spike/engine/autopilot controls) unstart behaviors if you tried to command thrust and vector change as a reactionary measure.

OTOH, where the Foxbat could only run at about Mach 2.34 in sustained cruise and took that up to about 2.65 for 15 minute sprints after a further 1-2 minute acceleration, the Habu would merrily gallumph along at about 2.61-2.79 with the 3.2 'official' max in reserve. And it's HUGE lifting body effect on wingloading was such that it could do some things with the speed profile without sacrificing absolute ceiling performance (fully half the MiG-25's effective 'lift' came off the inlets and then only in certain ramp/engine modes).

Of course the Blackbird also had a /vastly/ superior electronics suite.

Still there were a LOT of compromises for our mission profiles so that heading into an enclosed space like the Gulf of Bothnia or the Yellow Sea, you didn't squeeze yourself between tanking issues (inshore, 'oblique' to the dipsydoodle and recce run flyup profile, but also visible and vulnerable to long range intercept) and overflight.

These tended to make the jet a lot more vulnerable on egress than common sense said it should have been and is one of the reasons the Soviet Foxbat/Foxhound platforms (themselves with massive external as well as internal fuel supersonic-time boosting and an AAR probe later) did so much to shut down the BB's mission utility with pack tactics closing down the vector swing (The Acrid and Amos are both massively bigger than the Sparrow too).

'On a straight run', if you look at the shock patterns coming off the nose (draw a triangle) the SR-71 was good for about 3.7-4.0 and probably over 89,000ft. This should have been enough to limit A2A interception from anything outside +/- 20 degrees on the nose.

Whether it would be equally useful for the aircraft's original 'RS= SIOP' support mission is rather dubious IMO. Because even the Guild/Guideline had nuclear tip options. And the S-300V in particular could also make kinematic cutoff by 'hanging a curtain' of multishot weapons which rounded-the-top of a ballistic arc and then TVM'd their way into the SR-71's cockpit, from above.

Speed only really works when it is so high that you can make the rocket boosted alternative always have to slant /across/ as much as up to get you. And that in turn means leaving the high-penalty region of 4.0-6.0 with an envelope expansion on both ceiling and range rate numbers up to the 'sunline' declinator on a 200-400,000ft range and /minimum/ Mach-8 to 12.

In this mode you are a minimum 1,000-1,500km out from target grazing angle horizon on your sensor suite and constantly crossing the margin between waveriding and orbital insert behaviors which means your fuel burn goes back down towards a predictable and thermodynamically 'affordable' level /once you get into the groove/.

Fruthermore, the only thing which can touch you is typically DEW weapons as any kind of mechanical intercept has to strain just to (Brilliant Eyes) see you as it generates the kind of cross track collision-lead for a cuttoff.

The problem then being that the amount of power you need to put in to get out of the low hypersonics requires methane or slush-hydrogen in significant quantities and the storage, fueling, expansion and structurals-cooling questions deriving from this makes a real mess of your takeoff and climbout profiles. So bad in fact that you typically end up packaged as a 'Sanger' which, as the D-21 program showed, is also just not an easy or wise solution for preaccelerating a PDWE or Scram type powerplant up to 'higher and faster enough'.

IF ever we get there, technologically, with systems approaches like Falcon, the solution will pose entirely new strategic difficulties however, not least because the U.S. will no longer be an island continent or untouchable 'Arsenal Of Democracy'. It will be fully vulnerable to tactical, -conventional-, (albeit rod from god) attacks from any other overseas power with a like tech base. This will in turn mean the Space Weapons Treaties will have to go the way of the dinos. As you kill FOBS/TAV vehicles with lookdown/shootdown DEWs from orbital battlestations, not surface launch.


KPl.

[edit on 17-12-2005 by ch1466]

Originally posted by BigTrain
The SR-71 must have had so much fun toying with the swedes, lowering down to a resonable altitude, closing at mach 3, slowing to mach 2.5, just to let the pilots get alittle happy, and then rocketing away at mach 3.2+ 100,000 feet saying, catch this!!

Train

I can understand that this kind of speed is a great advantage if someone is trying to catch up with you, but I don´t quiet understand that the speed makes you invurnable to head-to-head colission with missiles.

Lets make a brief calculation. The PS-46/A radar in the viggen has a range of finding small targets of 40 nautical miles, which is aprox. 74km. And I doubt that the sr-71 has that little radar signature. Let's say that the sr-71 is flying 10000 m above the viggen, (not the case in sweden, but just to get some margin to our calculations) The skyflash moves in mach 4, and the sr-71 in mach 3. The sonic speed for heights over 36089 feet is 1062 km/h. That means that the sr-71 is moving with 3190 km/h and the skyflash with 4248 km/h. The range of the skyflash is 45km at high altitude. With the given altitude difference, the angle between the sr-71 and the viggen at detection is aprox. 8 degress. If the skyflash was launched at this point we would get the equations: (calculated i SI units m/s)

866t+1180t*cosa= 73300
1180t*sina=10000

Solving this gives us: t=36 a=13.72 degrees

This would be pushing it with the range of the skyflash, but the onboard computer would probably take care of this, since it has knowlage of maximum angle of atack for the missile, which i don´t have.

But is it not resonable to think that:
1. the sr-71 can't turn very fast at these speeds.
2. the sr-71 would on an normal flight in the baltic sea not fly higher then 10000 meter above the maximum altitude for the viggen.
3. the skyflash can increase its altitude with atleast 14 degrees.
4. it is quiet easy for a missile to calculate a hit on a non turning object, even if it is closing very fast.

Regards eric

I recall one of my engineering lecturers saying that at its maximum speed the safety factor of the Blackbird dropped to 0.8 meaning that it could not make fast course corrections at speed.

My Dad has told me of watching Lightnings taking off when he was stationed in South-East Asia. They would rotate to vertical and then head straight up, going through the sound barrier as they did so. Eventually the Brass banned that sort of behaviour because the afterburners were ripping up the tarmac.