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The original SFI PDF I posted had about half the pages missing because I messed up. I've replaced the link with a new, fixed one.

As promised, here is the unclassified part of the AJS 37 SFI (speciell förarinstruktion - the flight manual). I used ScanTailor Experimental to attempt to make a cleaner "scan" from my smartphone camera pics - let me know if it messed up somewhere. Fpl AJS 37: speciell förarinstruktion (100MB PDF)

Napalm bombs were taken out of service with the A 32 Lansen in the late 70's and were never integrated on the Viggen.

The Viggen's gigantic delta wing and large control surfaces make it capable of a very high instantaneous turn rate, but that same gigantic delta also means it loses speed very quickly in tight turns. You can throw it around real quick but sustained turn performance is mediocre at best. I agree though that 500 m sounds extremely low. For the Draken I have seen performance charts that show that even at flight idle you need something like 1500 meters of altitude to do a 7 G split S at entry speeds between Mach 0.4 and 0.6, and that's with no margin of error at all (exit altitude 0 meters). Then again the Draken actually had some limitations on control surface deflection because the hydraulics simply weren't powerful enough, and it also accelerated extremely quickly in a dive.

J 29 Tunnan was one of the big culprits after WW2. Poorly understood flight characteristics early on paired with a very well entrenched culture of blatant disregard for safety regulations led to a shocking number of crashes. Out of 661 J 29's that served in the Swedish air force, 242 were written off as a result of crashes or other accidents, and 99 pilots were killed. Lansen and Draken were both pretty bad as well, but over the entire service life of the Viggen, "only" about 30 or so were lost in accidents. The problem seems to finally be mostly under control today with the Gripen, which has had only five hull losses in 20 years (all air forces operating it as well as prototypes included), and no dead pilots. http://www.svfplhist.com has some more on this if you're interested.

Chefsingenjören's blog is great, there are a lot of cool posts there worth reading. Related to the story about blowing the roof shingles off of houses, there was an incident back in 2002 where a JA 37 actually burned and seriously hurt several people on the ground with the afterburner exhaust flame. The full investigation report is available in English, but in case you can't be bothered to read it, I'll post some choice quotes below. [ame]http://www.havkom.se/assets/reports/rm2003_01e.pdf[/ame] If you watch the first 15-20 seconds of this video below it becomes very apparent that Volvo Flygmotor wasn't kidding - the visible part of the AB exhaust flame is almost half the length of the aircraft (which is about 16 meters long in total) and it gives the pavement a good grilling on rotation: [ame] [/ame] That's the transonic stabilization/artificial stick forces thing I was talking about earlier.

SPAK (dämpning/spakkraftstyrning) is just oscillation dampening (in all three axes), artificial stick forces and a bit of stabilization in the transonic area. It's normally always on. It's a thing the autopilot does but I don't think it counts as a "real" autopilot mode.

No, there are no provisions for any bombs other than 120kg frag bombs, 15 kg concrete practice bombs and 80 kg flare/illumination bombs.

The autopilot (SA 06, where SA stands for "styrautomat") is capable of two modes: - Attitude hold/course hold: press the button ATT to activate. If pitch angle is <60° and bank angle is >7° and <66°, maintains both as they are. If bank angle is <7°, the aircraft instead enters course hold mode and maintains current course at neutral bank. While in this mode, autopilot controlled turns can be commanded by using the trim button on the stick. The bank angle used by the autopilot depends on airspeed and ranges from 10° at 200 km/h IAS to 45° at 800 km/h IAS. You can still control the aircraft in both pitch and roll axis while attitude hold/course hold is active, you just need to use some physical force to get the stick to move. If you do this and stay within the limits above, the aircraft will hold your new attitude when you let go of the stick. If you exceed the limits the autopilot will disconnect and enter a passive mode where it'll automatically reactivate once you get back within the limits. - Altitude hold: press button HÖJD to activate. Works exactly like the previous mode but the aircraft will also maintain current barometric altitude. Adjusting the altitude is done with the trim button on the stick. If you activate autothrottle with the landing gear in, it'll try to maintain 550 km/h IAS. You can't adjust that. It's really only intended for landing. tl;dr: if you activate the autopilot in a reasonable situation and let go of the stick, the plane will keep doing what it's doing. If you move the stick and enter some new reasonable situation that you like better, the plane will keep doing that instead. Quite reasonable, I think. It can't follow waypoint routes for you, though.

The JA 37 has a full tactical map screen where you can see your own aircraft, friendly aircraft, enemy aircraft, various navigational markers etc. The AJ and AJS 37 do not have this, but it does have an inertial navigation system with waypoint support. Course, altitude, distance to destination etc can be shown both on the head-down radar display and on the HUD. The head-down radar display has at least two display modes: one is a traditional B-scope for A2A work, and the other is a "sector PPI" for A2G.

It's a weird dual purpose warning light. REV AVDR stands for "reversering avdrag". If the thrust reverser is engaged, the light will turn on when the speed falls below 130 km/h, warning the pilot that he should reduce power. The lamp will also turn on while flying in the transonic region (mach 0.97-1.05). The airshow trick where you turn the aircraft around using the thrust reverser is not really recommended for everyday use; at low speeds the disturbed air and dust kicked up by the reverser risk getting sucked into the air intakes, which can lead to stalling and FOD. Also, if you use the wheel brakes while the plane is moving backwards, you risk planting the entire thing on its rear end.

28. Table of contents: (click for bigger)

Yes, but that's only the first ~20 pages (the first section, "flik 1" - the general description of the aircraft). There are another couple hundred unclassified pages that aren't in that PDF.

That's a page from the unclassified part of the flight manual. While it is not exactly a widely circulated publication, it's not particularly hard to find either. The national military archives' library has a copy, for example. My photos of it are really bad because I couldn't get the pages flat - I plan to fix that on Saturday or next week by just opening the binder and re-photographing it - but here's the entire "presentation" section of the SFI (and again, sorry for the quality): https://drive.google.com/file/d/0B8bCDRcq9BVeai1MaEplRzVXM3c/view?usp=sharing Your pic is from paragraph 4.2 - page 14 in the PDF above. This is very handy to know! I need to re-formulate my request then - I asked for all of it, but if they've already declassified parts of it I should be able to get those immediately. I thought it was going to take six months, because that's what happened with the SFI for J 35F which was finally declassified on my request the other week. Thanks!

2. Strömställare KONTROLL triggers the self-test system, you hold this and if things seem broken the appropriate warning lights turn on. Example: with landing gear out and locked (like, on the ground), press and hold this, and if any of the redundant "gear in" sensors fire, warning lights will turn on. 6. Strömställare TIPPVÄXEL - Right, this is pretty complex. The AJ 37 isn't fly-by-wire, but there's a gearing system that provides artificial stick forces so that when you're going really fast and the elevons exert a gigantic amount of force, pulling really hard on the stick doesn't deflect the elevons as far as when you're going slow. If this system fails or hydraulic system 2 fails, you can switch this gear into the low speed setting (large stick movements = large elevon deflection) by flipping the TIPPVÄXEL switch to the LANDN (landing) position. The SFI has a lot to say about the flight controls system, so you figure this out: http://imgur.com/a/SMZTC 19. Strömställare TÄNDSTIFT - Controls the "spark plugs" for the engine starter. I think this is supposed to be wired into place in the TILL position, but you can turn it off manually if you really want to kill the power. 38. Strömställare BRÄNSLEREGL Switches between automatic and manual fuel regulation (for emergencies).

AFAIK it's common on carrier aircraft, not so much on anything else. Most aircraft tend to have instructions that say "maintain so and so airspeed and be at such and such altitude at so and so many miles from the threshold". In the ILS system there's a defined glideslope you're supposed to follow, but you don't do this by maintaining a specific angle of attack.

A lot of the dubious things requires reading the SFI (Särskild Förarinstruktion - the flight manual) to understand what is going on. It's split into four parts, and only part 1 is unclassified. I have most (but not all) of part 1 photographed - I ran out of time at the national archives last time I was there and had to skip some sections that I thought was uninteresting. I'll go back, probably on Saturday or next week and photo the entire thing and put it up as a PDF. I've requested to have parts 2-4 declassified but the handling of such requests can take months. So to get to the point, here's what I've found in the SFI to clarify those points you've marked as unclear in your PDF: 1. Kanalväljare styrautomat - Selects which stick sensor channel to use. For use in case one of them fails. SFI chapter 1, section 12, page 28, paragraph 4.4.1. 7. Potentiometer LJUDSTYRKA UK-DÄMP - Volume control for the Sidewinders. Additionally, if you press and hold this, you get "100% UK-dämpning" - not sure what that means. Muting the radio? Dunno. 8. Tryckströmställare IR-RB FRAMSTEGN - In case of launching Sidewinders, Mavericks, BK 90 or rb 15 one by one, in order to proceed to the next weapon, you need to either make the weapons safe and then arm again, or press this button before you can launch the next weapon. The entire weapons section of the SFI is really confusing, probably because there are two parallel systems, the old analog system from the original AJ 37 and a newer computerized MIL-STD-1553-based system that they added with the AJS 37 mod. See SFI chapter 1, section 25. 39. Strömställare ÅTERSTART - This is indeed manual engine restart. It's supposed to restart automatically, but if it doesn't you press and hold this for two seconds. SFI chapter 1, section 9, page 32 and 33. 46. Reglagebroms - Enables or disables autothrottle (fittingly named "AFK", automatisk fartkontroll). While it is enabled the physical throttle handle is locked in position, hence the name "reglagebroms" (roughly, "lever brake"). You can disable it either with a kill switch on the throttle handle, by pulling back the reglagebroms again, or by using violence to force the throttle to move (the SFI says 100 Newton of force is needed). SFI chapter 1, section 10. By the way, the α 15.5° thing isn't just a warning light, it's also a toggle switch. When landing, you fly the final approach based on a target AoA, not on a target speed. Normally this target AoA is 12°, but pressing the button makes it 15.5° instead, in case you want to slam into the ground harder (recommended at road bases).

[ame] [/ame]

If I understand the flight manual correctly then no, it cannot. If you want to program the target data in the air, it looks like you basically have to punch the coordinates in on a keypad by hand.

I've read somewhere (no source, sorry - might be completely wrong) that TARAS was actually kicked out of the Gripen C/D. My narrative was mainly based on what Wiseman wrote a year ago - I figured he should know what he was talking about. If you have sources that prove me wrong I'd be very interested to read them, but Wiseman says when the Gripen C/D arrived there simply was no datalink anymore for many years. edit: seems I'm confused - the aircraft-to-aircraft link (TIDLS, which originated on the JA 37) is still in use, but the ground-to-air link/TARAS is not. I think? edit 2: right: [ame] [/ame] So you're correct in that the JA 37's fighter-to-fighter data link (or a modernized version of it) lives on even today. The ground-to-air link is a different thing these days though. I confused the two systems - my bad!

Correct. This is what the unclassified part of the flight manual has to say about the weapon: http://imgur.com/a/NtY7f To summarize in English, the guidance is inertial and target data (its geographical position in latitude/longitude) is either pre-loaded on the ground or programmed in flight via the data panel, which is next to the weapon selector panel on the right side of the cockpit. The dispenser approach altitude and sub-munition deployment altitude are both programmable independently of each other.

I believe the rb 05 was initially conceived as an alternative to the rb 04E. The rb 04 could not be used in archipelagos or anywhere other than on the open sea because its seeker couldn't tell the target from the ground clutter. Hence, a backup was needed since the dumb 450kg bombs used on the Lansen were out of fashion, and the rb 05A was born. Once it was there, you could use it against anything you'd use a Paveway on. There were plans for an optically guided version (like the Maverick) but the Air Force just bought the Maverick instead.

No, this is not the case. The Swedish data link system was implemented on the Gripen A and B, but when the big doctrine shift arrived in the early 2000's everything had to be NATO compatible, so on the Gripen C/D, along with changing all the instrumentation away from metric and a lot of other things, they threw out the old data link system and replaced it with the NATO standard Link 16. Or at least, that was the plan - in reality they put in the radios etc for Link 16 but didn't actually implement the software for old functionality that had been there even on the JA 37 (such as buddy illumination for the Skyflash, sharing of situational info between aircraft) for many years. It's there today (I think - the actual capabilities are probably classified) but there was a period of several years in the early 2000's when the Gripen C/D was actually less capable than the A/B in some ways. If you're interested in how the old data link system worked, I have some great reading for you: [ame]http://fht.nu/Dokument/Flygvapnet/flyg_publ_dok_svenska_flygvapnets_styrdatasystem.pdf[/ame] The system was originally really simple - one modem on the ground and one in the aircraft (initially J 35 only). The ground installation continuously sent data packets 103 bits long at 3000 bits/s, containing info about the target position, altitude, heading etc. Then it evolved over the years but the basics (including the 103-bit data packets!) persisted until the very end in the early 2000's. Not bad for a system designed in the dawn of the digital era...