renhanxue

Got a reply from the national archives re: the missing parts of the formerly classified SFI for the AJ 37: it wasn't that the missing tabs could not be declassified, it's just that they for whatever reason weren't in the binders to begin with. I think I shall try asking for the AJS 37 SFI next.

Lock in this case I think just means it follows the target automatically. There's no point in trying to paint the target since the AJ(S) 37 doesn't have any radar guided missiles.

Fpl AJ37: speciell förarinstruktion, del 2, kap 1, ändring 90 A package of updated pages from 1995. Among other things contains info about the new jammer pod, kapsel U22. Annoyingly I only got this one update pack - ideally I would've gotten all of them and could've been able to reconstruct a "final" version of the manual by replacing pages as instructed in the update packs, but this is the only one I got for whatever reason so here you go for now.

No, this is AJ 37 info only. I will request AJS 37 though and see what they say!

They're actually supposed to do that on all documents they declassify. Usually they're too lazy/busy though and just cross it out on the first page. The stamp itself doesn't have any legal effect, but it's a reminder to whoever handles the document that it could contain classified info, and unless you're responsible for the document you're supposed to trust it. No problem, glad you enjoy it. There's a bit more information in updated pages section from 1995 that's forthcoming (probably tomorrow), but I don't think there's a lot about rb 75/rb 24J there either. I suspect some of the info that was there might have been redacted too due to a non-disclosure agreement with the US.

Fpl AJ37: speciell förarinstruktion, del 3 (9 MB PDF) Performance charts, for all kinds of atmospheric conditions and loadouts. Chapter 7 (which contains information about maneuver performance, presumably rate of turn, rate of roll etc) is missing. Trivia: if I'm reading these graphs right, from a standstill on the ground, takeoff and acceleration to Mach 0.55 takes just over 30 seconds at full AB with a light combat loadout. From M 0.55 at a nominal 0 meters of altitude, accelerating to M 0.9 and climbing to 10 km with the same light combat loadout takes about 1 minute 45 seconds.

Without further ado, I present the first part of my findings from today: FPL AJ37: speciell förarinstruktion, del 2, kapitel 1 (57 MB PDF). Chapters 2-6 were not in what I received - I'm not sure if this was because they haven't been declassified or because they weren't in this publication. I have asked via email, but no reply yet. There are two more parts that I will upload later tonight: part 3, which is full of performance diagrams (climb times, acceleration times, top speeds at a given engine RPM, things like that), and a collection of updated pages for part 2 - basically an errata of things that have changed after its publication.

I don't, but even if I had, I wouldn't have been allowed to bring one into the national archives reading room. What I do have is my trusty camera and a program that makes document photos look like scans.

Speak of the devil, and he will soon appear on your doorstep. Look forward to tonight.

More than I knew! Thanks!

There were HEAT rockets for the Lansen and for the SK 60, but the Viggen's pods are HE (frag?) only AFAIK. Still waiting for a reply from the national archives re: the secret parts of the SFI.

4x rb 75 (Maverick) 2x rb 15, 4x rb 24 (Sidewinder) 2x rb 04 on the aircraft closest to the camera, 2x rb 24 + countermeasures pods on the farther aircraft (the text on the rb 04 nose says TRYCK EJ HÄR which means "don't press here") Mixed strike loadouts: rb 75, rocket pods, countermeasure pods.

post your favorite viggen paintjobs David 12, painted to resemble the symbol for the order of the Viggen knights (member association for people who had flown the Viggen) Urban 48. "Akktu stakki" is Lule Sami for "lonely wolf" and is the name Urban Röd (1st sqn/21st air wing out of Luleå) chose for themselves. Should explain the wolf motif. Petter 11, commemorating the disbanding of the 16th air wing out of Uppsala. An aside about Swedish military aircraft callsigns during the later cold war: the wing number (painted on the plane beneath the cockpit) is translated to a letter (1 = A, 2 = B etc) in the Swedish phonetic alphabet, which is then combined with the aircraft's tail number to form a callsign. 21-48 above is thus Urban (for 21) 48. Squadrons are named in a similar fashion, but instead of the tail number you get a color: red for 1st, blue for 2nd and yellow for 3rd. The first squadron of the 4th air wing out of Östersund is thus David Röd (where Röd obviously means red, duh). Swedish squadron badges from the cold war are frequently hilarious, by the way. Forget skulls, pirate flags, grim reapers and all that American "badass" stuff, in Sweden they didn't take that stuff seriously at all and you get squadron badges like these: (the latin is a direct translation of the squadron's motto "Filip Blå kan ingen slå", or "nobody beats Foxtrot Blue") (source: http://www.uniformsdetaljer.com)

Originally this was true but it was changed in the AJS mod (as well as on the JA 37, I believe) to deploy when the nose gear compresses at touch down. It's also deployed automatically in case of generator failure and can be deployed/stowed manually with a switch in the cockpit. It's also stowed automatically at gear up. (SFI AJS 37 tab 3 page 23; page 52 in the PDF.) I don't know what the purpose of deploying it automatically at touch down is, since it requires at least 300 km/h to deliver electrical current, but I've seen speculation that it might be because there's some service points behind the same hatch and since it's hydraulically actuated it can't be opened by the ground crew without hydraulic pressure in system 2, so it's always deployed on the ground. I can see the point of having it deployed at take off though, since it's nice to be able to instantly switch to reserve power in case of a generator failure at a critical phase of the flight. Inside the RAT hatch there's also a hand pump that can be used to build up some brake pressure, in order to be able to emergency brake the airplane while it is being towed on the ground.

My personal favorite Viggen thrust reverser video is this old classic: [ame] [/ame]

Before the AJ 37 Viggen was the A 32 Lansen, which had the same role. One of the last squadrons to fly it was "Filip Blå" at the 6th air wing out of Karlsborg. Here's a 1975 Super8 recording of some of those "silent men of honor" (with magnificent facial hair), the ones one of the test pilots were talking about in the JA 37 seminar above, doing their thing - with dumb bombs, though. Look out for some very, very low flying. Actual bombing run starts at at around 6:30. [ame] [/ame]

Bonus, a highly interesting 1983 issue of Ericsson Review, which covers the design of the JA 37's pulse-doppler radar as well as some radar theory in general: [ame]http://ericssonhistory.com/Global/Ericsson%20review/Ericsson%20Review.%201983.%20V.60/Ericsson_Review_Vol_60_1983_2.pdf[/ame]

Part 2:

I've translated some of the jucier parts of that for another forum. I'll just go ahead and paste them here. A few terms: - FMV is the Defense Materiel Administration, which was (and is) the government authority responsible for buying and developing all kinds of equipment for the Swedish armed forces. At the time when the Viggen was being developed, FMV still had a lot of engineers in house, which was considered important since it was thought at that time that in order to buy or develop a good system you had to know how it worked - they figured you had to understand the cutting edge technology in order to be able to write proper design requirements and adjust to technical challenges as they arose. - JA 37 is the fighter version of the Viggen. - AJ 37 is the strike version, which predates the fighter version by about ten years (entered service around 1970; the JA 37 around 1980). - 35/"aircraft 35" is the Draken. - 37/"aircraft 37" is the Viggen airframe in general. My comments are in parentheses. Please ask away if there's anything that seems unclear.

http://www.amf-arkiv.se/ You can order digital versions of old Swedish military film clips from here. Expensive, though.

Someone (I think it was former commander-in-chief and air force general Owe Wiktorin) described it with the more or less untranslatable word "fulsnygg", which I think fits perfectly. It's a moniker for a person who is attractive despite having features that would normally be regarded as ugly or at least not conventionally beautiful. Unlike a lot of fighter aircraft which have this sleek, graceful look going on, the Viggen is big, fat, angular, stubby-tailed and has weird bulges all over. It looks like it's been pumping iron at the gym. Nevertheless, from certain angles it can look downright elegant.

The JA 37 only got wired for AMRAAM's with the JA 37D upgrade in the mid-90's. The Skyflash is a British-developed improved version of the Sparrow (forget which version it was based on).

This is a typical "bas 90" - the newer model of dispersed basing, designed for the Viggen and built from the 70's and on: Letters H, B, C and D are runways, and all of them except H are widened road strips about 800 meters long. The triangles marked KC and BasC are fortified command bunkers (KC for the squadron, BasC for the base battalion), the smaller triangles are minor defensive bunkers/bomb shelters. The numbered squares along the roads are aircraft parking spots for one or two aircraft each. The numbered squares near the H runway are parking spots where aircraft can be held at high readiness with the engine running and the pilot in the cockpit, ready to take off for an intercept at a moment's notice. The base battalion that serves the base has, in addition to the aircraft mechanics etc, a good number of runway clearing assets (dump trucks, road graders, earthmovers, asphalt cookers, steamrollers etc etc). This base is supposed to house a single squadron (nominally 16 aircraft, usually plus a few spares). As you can see, there are about twice as many aircraft parking spots as there are aircraft, and they're all so far from each other that you'd have to use one guided weapon on each spot (camo/roofing makes sure you can't tell from the air if there's an aircraft in a given spot). Getting that sort of force into place requires a lot of time and effort, and back in the day PGM's were rare and expensive. The dispersed basing system was a reasonable response to the threats of the time.

As far as I understand it, no. It's all or nothing. You _may_ be able to fire one pod at a time but I don't think so.

Yeah, there's a lot of interesting quirks. In some ways (but not in others) the aircraft seems surprisingly ergonomic and user-friendly for its time. The fuel gauge is one example. On a lot of aircraft you get a display in kg/lbs in various tanks and everything else you get to figure out yourself, but here it's one single percentage meter that works both with and without the drop tank, and that also tells you if you're gonna have to turn back early or not. There are no manual flaps either, instead the canard flap setting is automatically adjusted depending on the landing gear position and the aircraft weight. Data input and output for things like setting the targeting data for the BK90 or waypoint data for the Rb 15F on the other hand is amazingly primitive. You get a number keypad, a LED display with six digits, an in/out selector and a knob which selects what system you want to work with. Better remember all those six-digit codes you might need! There's also a number of hilarious Sweden-specific "optimizations", especially in the navigation system - it really shows that the aircraft was only ever intended to be used in Sweden, or at least not outside Europe. For example, you can enter latitude and longitude into the nav system in any order, because longitude must be <40° while latitude must be >40° but <90°. Don't try going east of Yaroslavl or south of Madrid or the nav system will freak out! The nav system also comes pre-loaded with coordinates and "shortcuts" for all major Swedish bases so you don't need to punch in lat/long for those.