renhanxue

Viggens in the field (kinda literally in that first one). First one's most likely from the 70's, second from some big field maneuver in the late 80's IIRC.

Viggens in the field (kinda literally in that first one). First one's most likely from the 70's, second from some big field maneuver in the late 80's IIRC.

Viggens in the field (kinda literally in that first one). First one's most likely from the 70's, second from some big field maneuver in the late 80's IIRC.

Part 1 - general info, checklists, etc. Similar to the unclassified Sk 35C flight manual in English that's listed in the document thread, but contains more stuff (such as weapons procedures etc).
Part 2 - by far the most interesting part. Describes the airplane as a system and the working principles of its most important subsystems (radar, data link receiver, sights, armament etc) as well as its tactical use. Tons of cool diagrams in here.
Part 3 - performance charts for every imaginable situation and load alternative
Part 4 - more of the same
Climbing to 11000 meters eats about 25% of the internal fuel, by the way. It's a very intercepty interceptor.
For you poor unfortunate souls who don't read Swedish, I might be back later with more interesting tidbits.

Part 1 - general info, checklists, etc. Similar to the unclassified Sk 35C flight manual in English that's listed in the document thread, but contains more stuff (such as weapons procedures etc).
Part 2 - by far the most interesting part. Describes the airplane as a system and the working principles of its most important subsystems (radar, data link receiver, sights, armament etc) as well as its tactical use. Tons of cool diagrams in here.
Part 3 - performance charts for every imaginable situation and load alternative
Part 4 - more of the same
Climbing to 11000 meters eats about 25% of the internal fuel, by the way. It's a very intercepty interceptor.
For you poor unfortunate souls who don't read Swedish, I might be back later with more interesting tidbits.

Part 1 - general info, checklists, etc. Similar to the unclassified Sk 35C flight manual in English that's listed in the document thread, but contains more stuff (such as weapons procedures etc).
Part 2 - by far the most interesting part. Describes the airplane as a system and the working principles of its most important subsystems (radar, data link receiver, sights, armament etc) as well as its tactical use. Tons of cool diagrams in here.
Part 3 - performance charts for every imaginable situation and load alternative
Part 4 - more of the same
Climbing to 11000 meters eats about 25% of the internal fuel, by the way. It's a very intercepty interceptor.
For you poor unfortunate souls who don't read Swedish, I might be back later with more interesting tidbits.

Part 1 - general info, checklists, etc. Similar to the unclassified Sk 35C flight manual in English that's listed in the document thread, but contains more stuff (such as weapons procedures etc).
Part 2 - by far the most interesting part. Describes the airplane as a system and the working principles of its most important subsystems (radar, data link receiver, sights, armament etc) as well as its tactical use. Tons of cool diagrams in here.
Part 3 - performance charts for every imaginable situation and load alternative
Part 4 - more of the same
Climbing to 11000 meters eats about 25% of the internal fuel, by the way. It's a very intercepty interceptor.
For you poor unfortunate souls who don't read Swedish, I might be back later with more interesting tidbits.

Part 1 - general info, checklists, etc. Similar to the unclassified Sk 35C flight manual in English that's listed in the document thread, but contains more stuff (such as weapons procedures etc).
Part 2 - by far the most interesting part. Describes the airplane as a system and the working principles of its most important subsystems (radar, data link receiver, sights, armament etc) as well as its tactical use. Tons of cool diagrams in here.
Part 3 - performance charts for every imaginable situation and load alternative
Part 4 - more of the same
Climbing to 11000 meters eats about 25% of the internal fuel, by the way. It's a very intercepty interceptor.
For you poor unfortunate souls who don't read Swedish, I might be back later with more interesting tidbits.

The national archives emailed. About six months after I requested, they've finally declassified the secret parts of the J 35D and J 35F flight manuals. I know what I'm doing this afternoon.

The national archives emailed. About six months after I requested, they've finally declassified the secret parts of the J 35D and J 35F flight manuals. I know what I'm doing this afternoon.

The national archives emailed. About six months after I requested, they've finally declassified the secret parts of the J 35D and J 35F flight manuals. I know what I'm doing this afternoon.

The national archives emailed. About six months after I requested, they've finally declassified the secret parts of the J 35D and J 35F flight manuals. I know what I'm doing this afternoon.

Does anyone mind if I post some contextless tank porn? No? I photoed a several decimeters tall stack of photographs at the national archives this summer and I have no idea what to do with them. Should I just turn tanks.mod16.org into a photoblog in the style of Yuri Pasholok? In the meantime, have some samples:
People on tanks:

Strv m/42, Stockholm, April 1944.

Strv m/39, Strängnäs, 1942.

Strv m/41, Stockholm, 1943.

Strv m/42, 1944.
People pretty far above tanks:

Pvkv m/43 and Saab B17, June 1947.

Strv m/42 and Saab A21.

You like the Lansen? Have some more! I posted this on SA originally but it deserves getting spread.
Someone dug up, digitized and YouTubed a 1975 Super8 recording from the Swedish air force's 6th wing/2nd strike squadron. It's cold war as fuck. In those days, men were men, pilots had ridiculous mustaches, safety regulations about low altitude flying were still a thing for pansies, the squadron still flew the Lansen (one of the last squadrons to do so; the strike version left service for good in 1978), and dumb bombs were still a valid weapon choice against naval targets.
The original film was mute, so all sounds have been added in postproduction.

Highlights (but you should really watch the whole thing):
2:00 if you want to skip the briefing and the mustaches
4:00 actual low altitude flying starts
6:20 bombing run starts
8:10 and onwards to the end has some pretty cool low altitude shots, with the shadow of the plane occasionally giving an idea of how low they're flying

You like the Lansen? Have some more! I posted this on SA originally but it deserves getting spread.
Someone dug up, digitized and YouTubed a 1975 Super8 recording from the Swedish air force's 6th wing/2nd strike squadron. It's cold war as fuck. In those days, men were men, pilots had ridiculous mustaches, safety regulations about low altitude flying were still a thing for pansies, the squadron still flew the Lansen (one of the last squadrons to do so; the strike version left service for good in 1978), and dumb bombs were still a valid weapon choice against naval targets.
The original film was mute, so all sounds have been added in postproduction.

Highlights (but you should really watch the whole thing):
2:00 if you want to skip the briefing and the mustaches
4:00 actual low altitude flying starts
6:20 bombing run starts
8:10 and onwards to the end has some pretty cool low altitude shots, with the shadow of the plane occasionally giving an idea of how low they're flying

Got penetration figures (or, rather, distances) for all Swedish anti-tank weapons as of 1970 declassified today. Enjoy: http://imgur.com/a/RExzB
105 mm APDS L28 and L52A1 for the L7 gun (both the standard variant and the longer one mounted on the S-tank) are included.

That's someone who cut out the juicy parts of this.

Proceedings of Symposium on human engineering aspects of main battle tank design, as held at Shrivenham in April 1969.

Does anyone mind if I post some contextless tank porn? No? I photoed a several decimeters tall stack of photographs at the national archives this summer and I have no idea what to do with them. Should I just turn tanks.mod16.org into a photoblog in the style of Yuri Pasholok? In the meantime, have some samples:
People on tanks:

Strv m/42, Stockholm, April 1944.

Strv m/39, Strängnäs, 1942.

Strv m/41, Stockholm, 1943.

Strv m/42, 1944.
People pretty far above tanks:

Pvkv m/43 and Saab B17, June 1947.

Strv m/42 and Saab A21.

The mean goons over on SA roped me into writing an effortpost, so I figured it's only fair that you freeloaders get to enjoy it too.
 
So, suspensions. I'm going to introduce the book as well because it's probably the most Soviet book that ever existed. It is called TANK.     What makes this book so Soviet? Well, here's the first paragraph of the introduction:   "Under the guidance of the Communist party of the Soviet Union, our people built socialism, achieved a historical victory in the Great Patriotic War, and in launched an enormous campaign for the creation of a Communist society."   The next paragraph talks about the 19th Assembly of the CPSU, then a bit about how in the Soviet Union man no longer exploits man (now it's the other way around :haw:), then a little bit about the war again, then spends another three pages stroking the party's dick about production and growth. The word "tank" does not appear in the introduction.   The historical prelude section is written by someone who is a little closer to tanks and might be a little less politically reliable, since they actually give Tsarists credit for things. I guess they have to, since foreigners are only mentioned in this section when they are amazed by Russian progress. The next chapter is a Wikipedia-grade summary of various tank designs that gives WWI designs a pretty fair evaluation, then a huge section on Soviet tank development, then a tiny section on foreign tanks in WWII mostly consisting of listing all the mistakes their designers made. The party must have recuperated since the intro since we're in for another three pages of fellatio.   Having read so far, you might think that there is very little value in this sort of book, but then the writing style does a complete 180 and the rest of the book is 100% apolitical and mostly looks like this.     Which is what we care about, so let's begin. Bonus points to anyone who can identify what the diagram above is about. Sorry in advance if my terminology isn't 100% correct, there aren't exactly a lot of tank dictionaries lying around.   The book skips over primitive unsprung suspensions of WWI and starts off with describing the difference between independent suspensions and road-arm suspensions. In the former, every wheel is independently sprung. In the latter, two or more wheels are joined together by a spring. Some suspensions have a mix of these designs. For example, here's a simple road-arm suspension used in some Vickers designs and their derivatives. The two road wheels are connected by a spring and to the hull by a lever. A weight pushing down on top of the pair of wheels is going to compress the spring that's perpendicular to the ground, bringing the wheels closer together.     Here's a more complex road-arm suspension, with four wheels per unit instead of one, also AFAIK first used by Vickers and then migrating to an enormous amount of designs from there. This suspension provides springiness through a leaf spring that you can see above the four road wheels. The two pairs of wheels don't have their own springs. The black circles in the image show where the suspension elements can turn, keeping the tank flat while hugging the terrain.     Here's another road-arm suspension, similar to the first one. In this case, the spring is made of rubber instead of metal. Otherwise, the design is very similar. Two rubber bungs on the bottom of the axles prevent the wheels from slamming into each other too hard. This design was used by French tanks and nobody else.     For some reason, volute spring suspensions are completely absent from this section. This is the best image of a Vertical Volute Spring Suspension (early Shermans) that I could find. It's kind of similar to the first image, except the spring is a volute spring, and it's vertical instead of horizontal. Later Shermans used horizontal volute springs.     Of course, as the book points out, these suspension elements are very easy to damage externally and knocking out one part of the suspension will typically take out the rest of the assembly, so independent suspensions are the way to go. The best way to do this are torsion bars. The bar is attached to a lever that holds your road wheel. As pressure is applied to the road wheel, the bar subtly twists, remaining elastic enough to reset once the pressure is off. This image is kind of weird, but the part in the center is the part on the far left, zoomed in, showing you where the lever and the opposite side's torsion bar are attached. As you can see, road wheels in a torsion bar suspension are going to be a little off on one side, unlike what you're used to on cars and such.     Now, since torsion bars are metal bars on the floor, they are going to make your tank taller. If you want a tank that's as short as possible at the expense of width, you may want to consider a Christie like suspension. Here, much like in torsion bars, the pressure is transferred inside the tank, but instead of a bar to absorb it, it's a spring in a vertical (or angled) tube. In most tanks with this kind of suspension, the springs are on the inside, but if you want to make the tank roomier on the inside, you can have them on the outside too. If you're really fancy, you can put a spring within the spring like in this diagram.     Since this is a Soviet tank book, you gotta have a huge T-34 diagram. Here it is.     The T-34 uses Christie springs, which you can see in the diagram. The road wheel configuration is a mix of the externally dampened and internally dampened "Stalingrad type" road wheels. The former have more rubber for absorbing hits from terrain, but the latter use less rubber. When you're in Stalingrad and you have to make tanks with a rubber deficit, that's the kind you want. When road wheels from other factories were available, they would go in the front and then the back to absorb most of the impact from harsh terrain features, and the steel-rimmed wheels went in the middle. The diagram shows how both types of wheels work.   Rubber can't really take too much punishment, so the KV, being a heavy tank, went with internally dampened road wheels from the very beginning, with a ring of rubber on the inside around the axle.     And finally, idlers. If you don't have big Christie type wheels, you gotta have idlers so your saggy track doesn't fall off. This diagram shows the rubber coating on an idler, and also how the rear idler can adjust to tighten the track. A loose track makes more noise, gets worn more, and is liable to slip off.     Keep those tracks tight, and you'll be zooming towards glorious victory in no time flat!     Now, the book ends and my own stuff begins. I mentioned rubber, but not what a headache it was to tank designers. In hot weather, the rubber in your tracks and wheels tends to fall apart. If you go fast enough, tires that don't have proper ventilation are going to melt too. There was a lot of pre-war panic in the USSR about the German PzIII being able to do 70 kph on tracks, but once the Soviets started building SU-76Is on the PzIII chassis they found out that the speed had to be limited to a whopping 25 kph to keep the wear to a reasonable level.

Remember the White Elephant essay? No? Well maybe you shouldn't read it immediately before you read the long-awaited* sequel.
 
*May not actually have been awaited or even expected

le epic meme face XD
 
Have a copy of a post I made a while ago:
Here are some words about the JA 37 intercepts of the SR-71 during the 80's. Most of the text is translated or adapted from the book "System 37 Viggen" (Flyghistorisk revy, 2009).
The JA 37 tactics development unit got started quite early on with working on a mission profile for intercepting targets at very high altitudes. The targets considered were the SR-71 Blackbird and the MiG-25 Foxbat; both types were capable of mach 3 at altitudes above 20,000 meters (65,000 ft).
Since the Viggen obviously wasn't fast enough to catch up to the target, the profile they came up with involved the intercepting aircraft meeting the target on a directly opposite course, with intercept vectors and combat control provided by ground-based installations over datalink and/or regular speech radio (in Swedish terminology, the air combat control system was known as "Stril", portmanteu for "Stridsledning och luftbevakning", which means something like "combat control and aerial surveillance"). This meant the JA 37's PS-46 radar would be supported by the ground-based Stril ones, since the intercepting aircraft couldn't catch the target on its own radar in time to climb and accelerate to intercept.
The tactics and armament systems were developed in the JA 37 systems simulator at Saab, with the simulator connected to Stril. For obvious reasons there were no opportunities to practice against our own aircraft in reality. The mission profile started with acceleration in level flight to mach 1.35 at 8000 meters (~26,000 ft). Then the nose was raised to 3-5 degrees above the horizon in order to climb while accelerating further. The maximum altitude was kept within the 16000 meter envelope ceiling mandated during training.
The USAF SR-71 recon missions were commonly known as the "Baltic Express". Usually, the SR-71's entered the Baltic at an altitude of about 21,500 meters (70,000 ft) about 80 km south of Copenhagen, accelerated to mach 2.98-3.0, continued eastwards and then northwards along the coasts of East Germany, Poland and the Baltic states, followed by a left turn westward, crossing the Baltic sea to the Swedish side just south of Åland, then another left turn southward and flying through the narrow corridor of international airspace between Öland and Gotland. Initially the left turn westward south of Åland was so wide that the SR-71's ended up violating Swedish air space, which led to a diplomatic protest which caused the SR-71's to slow down to mach 2.54 during the turn before accelerating to mach 3 again on the southbound leg. Between 1977 and 1988, 322 such missions were flown; in a few cases the mission was also flown in reverse.
Map of a typical SR-71 flight (note the times - wallclock time - noted along the flight path, the violation of Swedish airspace near the top and the Soviets running circles in the top right):

The intercepts would typically be done around the place that says "0910" on the route, or slightly north of it.
Simulator training on the mission profile started in Norrköping at the 13th air wing (one of the first wings to receive JA 37's; it had been equipped with them during 1981) for both pilots and air combat controllers. You couldn't know who ended up getting the intercept, so everyone was trained. The first real intercept opportunity came on October 26th 1982, when a pair of Viggens encountered an SR-71 for the first time. One of the pilots tells the story:
 

The second intercept occurred a week later, on November 1st, 1982, with another pair of Viggens from the 13th air wing:
 

Another intercept worth mentioning involved a group of three Viggens and occurred on January 9th, 1986. The group started southward from Norrköping with the intention of intercept training, but immediately after takeoff it was ordered to prepare to intercept a target that was suspected to be a SR-71. The group climbed to 8000 meters on a southeasterly course and then turned northward over the Baltic sea southeast of Västervik, forming up in a column. At this point the JA 37 had been equipped with the fighter-to-fighter data link, so the Viggens could share targeting data with each other, not just with the ground. All three aircraft conducted a simulated missile firing independently. The intercept started at 13:14 local time and was complete at 13:25; the intercept point was about 50 km west of Visby, on the island of Gotland.
The target was flying at an altitude of 21,500 meters at mach 2.9 and as usual attempted to jam the PS-46 radar. The Viggen group had had plenty of time to climb and accelerate, so when the lead and the second aircraft had passed the target the flight lead called to continue at maximum speed since the mach number at that point was around 2.0. The third aircraft did not reply, though, so the leader asked for his status. The answer was "I'm gliding". The third aircraft had suffered a high temperature engine stall. The engine had stalled briefly, the exhaust temperature rose and the warning light "EXHAUST TEMP." was lit. The pilot followed procedure and turned the engine off, and then restarted it when he descended below 12,000 meters. Having the engine stall at that kind of altitude was very scary since without bleed air from the engine, the cabin would lose pressurization within minutes. The entire group exceeded 18,000 meters of altitude during the intercept.
The fighter version of the Viggen really wasn't what you'd normally consider well suited to high speed/high altitude intercepts. It had fixed engine intakes, which meant it couldn't exceed mach 2 and it ordinarily had a ceiling of 16,000 meters, where its performance was decent for its time but not really comparable to that of purpose-built high altitude interceptors. Flying it at such high altitudes could be risky; the engine and the intakes were operating at the very edge of their capabilities and there was a passage in the flight manual that cautioned against "hammershocks" in the intakes that could possibly tear the aircraft apart if the engine stalled at high speed and high altitude. Nevertheless, in many cases it succeeded with intercepting even such a difficult target as the SR-71 anyway (over 50 successful intercepts recorded by the air force during the 1982-1988 period). The success can be attributed in part to the predictable flight paths but also to the aircraft's excellent data links, which were quite exceptional for its time and made it a lot more capable interceptor than it would otherwise be. Catching up to the target is one thing, but you also need to know where to find it.

le epic meme face XD
 
Have a copy of a post I made a while ago:
Here are some words about the JA 37 intercepts of the SR-71 during the 80's. Most of the text is translated or adapted from the book "System 37 Viggen" (Flyghistorisk revy, 2009).
The JA 37 tactics development unit got started quite early on with working on a mission profile for intercepting targets at very high altitudes. The targets considered were the SR-71 Blackbird and the MiG-25 Foxbat; both types were capable of mach 3 at altitudes above 20,000 meters (65,000 ft).
Since the Viggen obviously wasn't fast enough to catch up to the target, the profile they came up with involved the intercepting aircraft meeting the target on a directly opposite course, with intercept vectors and combat control provided by ground-based installations over datalink and/or regular speech radio (in Swedish terminology, the air combat control system was known as "Stril", portmanteu for "Stridsledning och luftbevakning", which means something like "combat control and aerial surveillance"). This meant the JA 37's PS-46 radar would be supported by the ground-based Stril ones, since the intercepting aircraft couldn't catch the target on its own radar in time to climb and accelerate to intercept.
The tactics and armament systems were developed in the JA 37 systems simulator at Saab, with the simulator connected to Stril. For obvious reasons there were no opportunities to practice against our own aircraft in reality. The mission profile started with acceleration in level flight to mach 1.35 at 8000 meters (~26,000 ft). Then the nose was raised to 3-5 degrees above the horizon in order to climb while accelerating further. The maximum altitude was kept within the 16000 meter envelope ceiling mandated during training.
The USAF SR-71 recon missions were commonly known as the "Baltic Express". Usually, the SR-71's entered the Baltic at an altitude of about 21,500 meters (70,000 ft) about 80 km south of Copenhagen, accelerated to mach 2.98-3.0, continued eastwards and then northwards along the coasts of East Germany, Poland and the Baltic states, followed by a left turn westward, crossing the Baltic sea to the Swedish side just south of Åland, then another left turn southward and flying through the narrow corridor of international airspace between Öland and Gotland. Initially the left turn westward south of Åland was so wide that the SR-71's ended up violating Swedish air space, which led to a diplomatic protest which caused the SR-71's to slow down to mach 2.54 during the turn before accelerating to mach 3 again on the southbound leg. Between 1977 and 1988, 322 such missions were flown; in a few cases the mission was also flown in reverse.
Map of a typical SR-71 flight (note the times - wallclock time - noted along the flight path, the violation of Swedish airspace near the top and the Soviets running circles in the top right):

The intercepts would typically be done around the place that says "0910" on the route, or slightly north of it.
Simulator training on the mission profile started in Norrköping at the 13th air wing (one of the first wings to receive JA 37's; it had been equipped with them during 1981) for both pilots and air combat controllers. You couldn't know who ended up getting the intercept, so everyone was trained. The first real intercept opportunity came on October 26th 1982, when a pair of Viggens encountered an SR-71 for the first time. One of the pilots tells the story:
 

The second intercept occurred a week later, on November 1st, 1982, with another pair of Viggens from the 13th air wing:
 

Another intercept worth mentioning involved a group of three Viggens and occurred on January 9th, 1986. The group started southward from Norrköping with the intention of intercept training, but immediately after takeoff it was ordered to prepare to intercept a target that was suspected to be a SR-71. The group climbed to 8000 meters on a southeasterly course and then turned northward over the Baltic sea southeast of Västervik, forming up in a column. At this point the JA 37 had been equipped with the fighter-to-fighter data link, so the Viggens could share targeting data with each other, not just with the ground. All three aircraft conducted a simulated missile firing independently. The intercept started at 13:14 local time and was complete at 13:25; the intercept point was about 50 km west of Visby, on the island of Gotland.
The target was flying at an altitude of 21,500 meters at mach 2.9 and as usual attempted to jam the PS-46 radar. The Viggen group had had plenty of time to climb and accelerate, so when the lead and the second aircraft had passed the target the flight lead called to continue at maximum speed since the mach number at that point was around 2.0. The third aircraft did not reply, though, so the leader asked for his status. The answer was "I'm gliding". The third aircraft had suffered a high temperature engine stall. The engine had stalled briefly, the exhaust temperature rose and the warning light "EXHAUST TEMP." was lit. The pilot followed procedure and turned the engine off, and then restarted it when he descended below 12,000 meters. Having the engine stall at that kind of altitude was very scary since without bleed air from the engine, the cabin would lose pressurization within minutes. The entire group exceeded 18,000 meters of altitude during the intercept.
The fighter version of the Viggen really wasn't what you'd normally consider well suited to high speed/high altitude intercepts. It had fixed engine intakes, which meant it couldn't exceed mach 2 and it ordinarily had a ceiling of 16,000 meters, where its performance was decent for its time but not really comparable to that of purpose-built high altitude interceptors. Flying it at such high altitudes could be risky; the engine and the intakes were operating at the very edge of their capabilities and there was a passage in the flight manual that cautioned against "hammershocks" in the intakes that could possibly tear the aircraft apart if the engine stalled at high speed and high altitude. Nevertheless, in many cases it succeeded with intercepting even such a difficult target as the SR-71 anyway (over 50 successful intercepts recorded by the air force during the 1982-1988 period). The success can be attributed in part to the predictable flight paths but also to the aircraft's excellent data links, which were quite exceptional for its time and made it a lot more capable interceptor than it would otherwise be. Catching up to the target is one thing, but you also need to know where to find it.

le epic meme face XD
 
Have a copy of a post I made a while ago:
Here are some words about the JA 37 intercepts of the SR-71 during the 80's. Most of the text is translated or adapted from the book "System 37 Viggen" (Flyghistorisk revy, 2009).
The JA 37 tactics development unit got started quite early on with working on a mission profile for intercepting targets at very high altitudes. The targets considered were the SR-71 Blackbird and the MiG-25 Foxbat; both types were capable of mach 3 at altitudes above 20,000 meters (65,000 ft).
Since the Viggen obviously wasn't fast enough to catch up to the target, the profile they came up with involved the intercepting aircraft meeting the target on a directly opposite course, with intercept vectors and combat control provided by ground-based installations over datalink and/or regular speech radio (in Swedish terminology, the air combat control system was known as "Stril", portmanteu for "Stridsledning och luftbevakning", which means something like "combat control and aerial surveillance"). This meant the JA 37's PS-46 radar would be supported by the ground-based Stril ones, since the intercepting aircraft couldn't catch the target on its own radar in time to climb and accelerate to intercept.
The tactics and armament systems were developed in the JA 37 systems simulator at Saab, with the simulator connected to Stril. For obvious reasons there were no opportunities to practice against our own aircraft in reality. The mission profile started with acceleration in level flight to mach 1.35 at 8000 meters (~26,000 ft). Then the nose was raised to 3-5 degrees above the horizon in order to climb while accelerating further. The maximum altitude was kept within the 16000 meter envelope ceiling mandated during training.
The USAF SR-71 recon missions were commonly known as the "Baltic Express". Usually, the SR-71's entered the Baltic at an altitude of about 21,500 meters (70,000 ft) about 80 km south of Copenhagen, accelerated to mach 2.98-3.0, continued eastwards and then northwards along the coasts of East Germany, Poland and the Baltic states, followed by a left turn westward, crossing the Baltic sea to the Swedish side just south of Åland, then another left turn southward and flying through the narrow corridor of international airspace between Öland and Gotland. Initially the left turn westward south of Åland was so wide that the SR-71's ended up violating Swedish air space, which led to a diplomatic protest which caused the SR-71's to slow down to mach 2.54 during the turn before accelerating to mach 3 again on the southbound leg. Between 1977 and 1988, 322 such missions were flown; in a few cases the mission was also flown in reverse.
Map of a typical SR-71 flight (note the times - wallclock time - noted along the flight path, the violation of Swedish airspace near the top and the Soviets running circles in the top right):

The intercepts would typically be done around the place that says "0910" on the route, or slightly north of it.
Simulator training on the mission profile started in Norrköping at the 13th air wing (one of the first wings to receive JA 37's; it had been equipped with them during 1981) for both pilots and air combat controllers. You couldn't know who ended up getting the intercept, so everyone was trained. The first real intercept opportunity came on October 26th 1982, when a pair of Viggens encountered an SR-71 for the first time. One of the pilots tells the story:
 

The second intercept occurred a week later, on November 1st, 1982, with another pair of Viggens from the 13th air wing:
 

Another intercept worth mentioning involved a group of three Viggens and occurred on January 9th, 1986. The group started southward from Norrköping with the intention of intercept training, but immediately after takeoff it was ordered to prepare to intercept a target that was suspected to be a SR-71. The group climbed to 8000 meters on a southeasterly course and then turned northward over the Baltic sea southeast of Västervik, forming up in a column. At this point the JA 37 had been equipped with the fighter-to-fighter data link, so the Viggens could share targeting data with each other, not just with the ground. All three aircraft conducted a simulated missile firing independently. The intercept started at 13:14 local time and was complete at 13:25; the intercept point was about 50 km west of Visby, on the island of Gotland.
The target was flying at an altitude of 21,500 meters at mach 2.9 and as usual attempted to jam the PS-46 radar. The Viggen group had had plenty of time to climb and accelerate, so when the lead and the second aircraft had passed the target the flight lead called to continue at maximum speed since the mach number at that point was around 2.0. The third aircraft did not reply, though, so the leader asked for his status. The answer was "I'm gliding". The third aircraft had suffered a high temperature engine stall. The engine had stalled briefly, the exhaust temperature rose and the warning light "EXHAUST TEMP." was lit. The pilot followed procedure and turned the engine off, and then restarted it when he descended below 12,000 meters. Having the engine stall at that kind of altitude was very scary since without bleed air from the engine, the cabin would lose pressurization within minutes. The entire group exceeded 18,000 meters of altitude during the intercept.
The fighter version of the Viggen really wasn't what you'd normally consider well suited to high speed/high altitude intercepts. It had fixed engine intakes, which meant it couldn't exceed mach 2 and it ordinarily had a ceiling of 16,000 meters, where its performance was decent for its time but not really comparable to that of purpose-built high altitude interceptors. Flying it at such high altitudes could be risky; the engine and the intakes were operating at the very edge of their capabilities and there was a passage in the flight manual that cautioned against "hammershocks" in the intakes that could possibly tear the aircraft apart if the engine stalled at high speed and high altitude. Nevertheless, in many cases it succeeded with intercepting even such a difficult target as the SR-71 anyway (over 50 successful intercepts recorded by the air force during the 1982-1988 period). The success can be attributed in part to the predictable flight paths but also to the aircraft's excellent data links, which were quite exceptional for its time and made it a lot more capable interceptor than it would otherwise be. Catching up to the target is one thing, but you also need to know where to find it.

le epic meme face XD
 
Have a copy of a post I made a while ago:
Here are some words about the JA 37 intercepts of the SR-71 during the 80's. Most of the text is translated or adapted from the book "System 37 Viggen" (Flyghistorisk revy, 2009).
The JA 37 tactics development unit got started quite early on with working on a mission profile for intercepting targets at very high altitudes. The targets considered were the SR-71 Blackbird and the MiG-25 Foxbat; both types were capable of mach 3 at altitudes above 20,000 meters (65,000 ft).
Since the Viggen obviously wasn't fast enough to catch up to the target, the profile they came up with involved the intercepting aircraft meeting the target on a directly opposite course, with intercept vectors and combat control provided by ground-based installations over datalink and/or regular speech radio (in Swedish terminology, the air combat control system was known as "Stril", portmanteu for "Stridsledning och luftbevakning", which means something like "combat control and aerial surveillance"). This meant the JA 37's PS-46 radar would be supported by the ground-based Stril ones, since the intercepting aircraft couldn't catch the target on its own radar in time to climb and accelerate to intercept.
The tactics and armament systems were developed in the JA 37 systems simulator at Saab, with the simulator connected to Stril. For obvious reasons there were no opportunities to practice against our own aircraft in reality. The mission profile started with acceleration in level flight to mach 1.35 at 8000 meters (~26,000 ft). Then the nose was raised to 3-5 degrees above the horizon in order to climb while accelerating further. The maximum altitude was kept within the 16000 meter envelope ceiling mandated during training.
The USAF SR-71 recon missions were commonly known as the "Baltic Express". Usually, the SR-71's entered the Baltic at an altitude of about 21,500 meters (70,000 ft) about 80 km south of Copenhagen, accelerated to mach 2.98-3.0, continued eastwards and then northwards along the coasts of East Germany, Poland and the Baltic states, followed by a left turn westward, crossing the Baltic sea to the Swedish side just south of Åland, then another left turn southward and flying through the narrow corridor of international airspace between Öland and Gotland. Initially the left turn westward south of Åland was so wide that the SR-71's ended up violating Swedish air space, which led to a diplomatic protest which caused the SR-71's to slow down to mach 2.54 during the turn before accelerating to mach 3 again on the southbound leg. Between 1977 and 1988, 322 such missions were flown; in a few cases the mission was also flown in reverse.
Map of a typical SR-71 flight (note the times - wallclock time - noted along the flight path, the violation of Swedish airspace near the top and the Soviets running circles in the top right):

The intercepts would typically be done around the place that says "0910" on the route, or slightly north of it.
Simulator training on the mission profile started in Norrköping at the 13th air wing (one of the first wings to receive JA 37's; it had been equipped with them during 1981) for both pilots and air combat controllers. You couldn't know who ended up getting the intercept, so everyone was trained. The first real intercept opportunity came on October 26th 1982, when a pair of Viggens encountered an SR-71 for the first time. One of the pilots tells the story:
 

The second intercept occurred a week later, on November 1st, 1982, with another pair of Viggens from the 13th air wing:
 

Another intercept worth mentioning involved a group of three Viggens and occurred on January 9th, 1986. The group started southward from Norrköping with the intention of intercept training, but immediately after takeoff it was ordered to prepare to intercept a target that was suspected to be a SR-71. The group climbed to 8000 meters on a southeasterly course and then turned northward over the Baltic sea southeast of Västervik, forming up in a column. At this point the JA 37 had been equipped with the fighter-to-fighter data link, so the Viggens could share targeting data with each other, not just with the ground. All three aircraft conducted a simulated missile firing independently. The intercept started at 13:14 local time and was complete at 13:25; the intercept point was about 50 km west of Visby, on the island of Gotland.
The target was flying at an altitude of 21,500 meters at mach 2.9 and as usual attempted to jam the PS-46 radar. The Viggen group had had plenty of time to climb and accelerate, so when the lead and the second aircraft had passed the target the flight lead called to continue at maximum speed since the mach number at that point was around 2.0. The third aircraft did not reply, though, so the leader asked for his status. The answer was "I'm gliding". The third aircraft had suffered a high temperature engine stall. The engine had stalled briefly, the exhaust temperature rose and the warning light "EXHAUST TEMP." was lit. The pilot followed procedure and turned the engine off, and then restarted it when he descended below 12,000 meters. Having the engine stall at that kind of altitude was very scary since without bleed air from the engine, the cabin would lose pressurization within minutes. The entire group exceeded 18,000 meters of altitude during the intercept.
The fighter version of the Viggen really wasn't what you'd normally consider well suited to high speed/high altitude intercepts. It had fixed engine intakes, which meant it couldn't exceed mach 2 and it ordinarily had a ceiling of 16,000 meters, where its performance was decent for its time but not really comparable to that of purpose-built high altitude interceptors. Flying it at such high altitudes could be risky; the engine and the intakes were operating at the very edge of their capabilities and there was a passage in the flight manual that cautioned against "hammershocks" in the intakes that could possibly tear the aircraft apart if the engine stalled at high speed and high altitude. Nevertheless, in many cases it succeeded with intercepting even such a difficult target as the SR-71 anyway (over 50 successful intercepts recorded by the air force during the 1982-1988 period). The success can be attributed in part to the predictable flight paths but also to the aircraft's excellent data links, which were quite exceptional for its time and made it a lot more capable interceptor than it would otherwise be. Catching up to the target is one thing, but you also need to know where to find it.