renhanxue

Yeeeeah. Like, what's going to happen if you take this huge scary jump to the open beta tomorrow is that you're going to get to install a patch, which is exactly what would have happened anyway, and you will be incompatible with some multiplayer servers for about a week, because in all likelihood next patch will make this open beta version the new stable release. You don't need to install an entirely new client and there is nothing "extra" you need to download. You are going to get this patch sooner or later, the only question is when. There was always going to be a patch to release the aircraft, so literally the only difference here is that you need to choose to install it now instead of in one or two weeks. Okay sure if you love multiplayer and the Viggen and your favorite servers are going to be running the stable version (I've already seen several server admins announce that they're gonna be on open beta) you'll have to choose between the two for about a week or two, but there's nothing that stops you from patching back to 1.5.5 if you change your mind. I really, really don't see what the big deal is here.

I'll translate the full lines on each point you've listed, not just the parts you've copied. In some cases I've gone to the more detailed checklist (with more than just mnemonics) in the SFI to clarify what's going on. 1. Tailfin pitot tube protective cover --- Removed 3. Starboard equipment compartment --- Settings 5. Nose gear torque link --- Connected 6. Nose pitot tube protective cover --- Removed Fpl = short for "flygplan", so "A/C" which is what you typically shorten "aircraft" to is a good translation here. A/C prepared for flight (I don't know the proper aeronautical English term for this - the Swedish word is military aero jargon for an aircraft that has been gone over by the ground crew as per procedures, fueled and armed.) 3. HUD camera/forehead cover --- Fixed in position (the Rka, "registerkamera" is not implemented in DCS, and the "forehead cover" is the big bit of plastic just under the HUD with a big emergency procedures label on it) 8. Leg restraints --- Connected (leg restraints for the ejection seat, "fastened" would also work instead of "connected") 9. Warning lights --- As desired (It is referring to the warning lights but I don't know what they mean by "as desired" at all) 14. Strap in 18. Ventilation: * Temp --- As desired * Mode switch --- AUT * Emergency switch --- TILL 31. Reconnaissance mode switch --- As desired (The F after the number on the checklist indicates that this is a AJSF 37 only item. The switch only exists on the photo recon version.) 32. Radar stick --- Parked 38. I-ind/sight switch --- As desired (Again, AJSF 37 only. "Ind" stands for indicator but I dunno what exactly the switch does or what the I-ind is for) 40. CI light hood --- fixed (H = AJSH 37 only. The hood is just a plastic cover mounted above the radar screen, shading it a bit so it's easier to see details in bright sunlight.) 49. Frequency control --- As desired (AJSH 37 only, again) 50. Radar series/Box --- As desired (AJSH 37 only again, but RUTA means "box" or "rectangle" and is used in the nav system on the AJS 37 as well) 55. GPU-powered flight suit ventilation temperature --- As desired 56. Gas mask stowage bin --- Locked 58. Self-test switch A --- Position ÖVRIG EL NIK ("other electronics") 63. Weapon selector --- As desired (The weapon selector is sometimes referred to as a "J/A-väljare" or "jaktattackväljare", or in English an air-to-air/air-to-ground selector, kinda) 64. Aiming selector --- As desired (For some reason the knob that controls bomb intervals, wingspan ranging in the HUD and illumination bomb alignment is called an "aiming selector") 68. Emergency panel --- All switches down 1. Contact (Give the ground crew chief the "contact" hand sign, so he knows you're going to be starting the engine - yes, the hand sign and the terminology goes back to old prop planes where the mechanic had to turn the prop over by hand to start the engine) 2. Start switch --- TILL, hold 2 seconds, start the aircraft stopwatch (The stopwatch function on the aircraft clock is called a "tersur" for some reason, possibly because it uses a third hand or something, I dunno, it's a fairly cryptic word even to a native Swedish speaker) 3. Check: * Warning light STARTSYST --- On within 5 s - If not, start switch --- FRÅN * Exhaust temp --- Max 400°C - In case of overheating, quick acceleration past ground idle (MTG, "marktomgång") or RPM < 50% - Throttle --- To engine cutoff position - Start switch --- FRÅN 8. Check pod overheating (AJSH 37 only, dunno what pod it's referring to, there are several possible) 12. Remove straps (The ones that hold you to the seat, that is. You say "strap in", but is "strap out" actually a thing?) 13. Engine shutdown sign (Give the ground crew chief the engine shutdown handsign; this tells him it's safe to approach the aircraft and refueling/rearming can begin - once this is done you are no longer supposed to touch any switches in cockpit or use the radio, for the safety of the ground crew) 5. Data panel selector in the BANA/GRÄNS mode: * Runway heading and TILS channel * Flip runway heading to opposite direction if necessary (mnemonic "BANA UT"; BANA/GRÄNS mode, I/O switch UT, press button L MÅL) * Ingress/egress borders(s) for each waypoint 9. Data panel selector in the ID-NR mode: (For IFF, not implemented in DCS) * Mission and squadron number on waypoint button B1 * Date on button B2 15. Data selector in the TID mode: * Check time to throttle up * Check time on target Right, so this is pretty complicated. When flying radar recon missions (master mode SPA), target position and movement is recorded by taking radar fixes on the target position repeatedly. These fixes are numbered R1 to R10 and to see/read out the recorded data on the data panel you first press the LS/SKU button, then the waypoint button corresponding to the fix number you want to see, then press the fix trigger to the first detent and release it (T1-T0) to see the recorded latitude. Then do T1-T0 again to see longitude, then repeat the same thing again ("återupprepa") to see target course and speed between fixes as calculated by the computer. No idea if all that is implemented in DCS or not.

Try "C:\DCS World\bin\DCS_updater.exe" update 1.5 with the quotation marks placed exactly like that.

Yeah I dunno why they never bothered giving it countermeasures that didn't occupy a weapon station. The BOL (countermeasures dispenser integrated into an AIM-9 launcher mount) was definitely around at the time of the AJS upgrade and I'm pretty sure the JA 37 could use it.

Correct. In reality there were no 1 KB pod/1 autocannon pod combinations approved for flight but I don't think there was anything technical stopping you from doing that. The KB pod could be combined with a whole bunch of different things on the opposite pylon so I can't see why the autocannon pod wouldn't be possible. It's certainly not a weight imbalance issue since you can have a loadout with a KB pod on one wing pylon and a rb 04 on the other - the rb 04 is more than double the weight of the KB pod. e: there might be something I don't understand going on behind the scenes though. KB + 1 AIM-9 + 2 rb75 is approved but KB + 3 rb75 is not, and the only autocannon+rb75 loadout that's approved is 2 gun pods + 1 rb 75 + 1 AIM-9, not 2+2 gun pods/rb 75 like you'd expect. Might possibly have something to do with center of mass, I guess? Just speculating though.

The word in Swedish is "stolpbana", where bana means track, path or trajectory and stolp(e) is a pole (as in flagpole, not as in the North Pole), post (as in fencepost or goalpost) or stake. Both pole track and post track are okay translations but I think pole track has less potential for confusion. edit: I may have misunderstood what you're asking about. The pole track consists of the pair of three vertical lines (short line near the center, longer line a bit further out and longest line to the furthest out) on both sides of the gap in the center of the artificial horizon. Imagine that those vertical lines are fenceposts standing on the ground, forming a track stretching away in front of you. To maintain the correct altitude for your programmed waypoint or selected weapon, align the aircraft with the top of the poles - that is, make the top of the vertical lines touch the artificial horizon.

There's a section in the SFI (flight manual for the real aircraft) that describes procedures for check flights - that is, test flying the aircraft after maintenance or some other event and putting it through its paces to ensure that all onboard systems are working as intended. When it gets to the part when you're checking the barometric altimeters, the procedure is as follows: By parallel to the isobars they mean ensuring that you're not flying towards or away from a low or high pressure center, so something like the blue line I've drawn here as an example: Does DCS model pressure centers at all? :V

Mattebubben is correct. In general, you decide on one major weapon system you want to carry and then you can add AIM-9's and/or countermeasures to that. No other mixing is possible, with the gun pods being the only exception - they can be combined with rb 05 and rb 75. Asymmetric loadouts are possible in reality though, like KB pod (flares/chaff) + 1 AIM-9 + 1 or 2 rb 75 is an explicitly allowed combination for example, but I dunno if that's implemented in DCS. One of the main reasons for this limitation is the design of the weapon selector knob, which uses the same position to mean different things with different weapon systems. I don't think they thought when designing it that mixing weapon systems was a particularly common use case, especially not since the aircraft for a large part of its life only had four usable weapon stations.

Yep, QFE depends on weather. Each air wing had its own meteorology section that did weather flights daily, usually more than once. Figuring out the target altitude was trickier. For preplanned missions (that is, the only kind of mission the AJ 37 flew for the majority of its career) you'd usually just look at a map (militaries love maps), so the kneeboard QFE data is a pretty good abstraction of this going on in the background. If you were doing something a bit more improvised you'd hopefully have a FAC or someone like that who could figure it out for you. If not, well, you'd have to either eyeball it or use the radar altimeter on a similarly elevated section of the terrain. Artillery has the same problem of finding the target elevation, and the solution is the same - either you guess based on a map or you have your forward observer figure it out.

I may be remembering wrong. 1988 was the year I remembered but I can't remember where I saw it. May have been in SIPRI's arms transfer database or something.

IIRC the autopilot takes control in pitch and yaw, but not in roll. It will tell you on the HUD what it wants you to do in the roll axis, though. No idea why they did it that way. But no, the JA 37 isn't stellar in a sustained dogfight compared to other 80's fighters. No all-aspect heaters before, what, 1988?, no fancy off-boresight tricks like on the MiG-29 and the sustained turn rate isn't great, nor is the thrust anything special, and in a drawn-out fight the need to use very high afterburner thrust settings to keep speed up in turns shortens its already short legs pretty quickly. BVR though it can be a pretty interesting opponent before 1990-ish, especially if not operating alone. The PS-46/A was a very good radar for its time, situational awareness is great with the tactical map screen and there's potential for buddy illumination for the Skyflash as well as other neat tricks. Only two radar missiles, though.

I have a hard time thinking of a more obscure and practically useless skill to learn than early 1970's military aviation jargon, long out of use, in a language spoken by less than 0.15% of the world's population, where said jargon is also highly specific to a long retired aircraft of which less than 150 airframes were ever built, and only one of which remains flying today. Which of course means that yes you should learn it you numbnut, what are you waiting for? Do you even realize what kind of stupidly exclusive club doing that puts you in? The only people who ever had any reason to learn this stuff were the pilots, and there really weren't very many of those. We're talking about maybe a couple thousand people, tops. It's the best combination of hipster and nerd cred you'll ever come across!

I made a thing that might conceivably be of interest to someone, so I might as well post it. AJS 37 electrical power supply, block diagram, translated:

Official English cockpit has been confirmed, don't worry.

No, in part 7 he explicitly wonders why the RWR isn't doing anything and cycles it with that exact knob. I think there might be a bug somewhere because it should be working.

Single guy with few commitments working a 9-5 desk job, so it's not too hard... I was actually at university last year doing history, and then it was even less hard. Also, digging in the classified archives consists of 99.2% waiting for them to actually declassify things, 0.3% paging through stuff you're not interested in but which happened to be in the same file, and 0.5% highly interesting reading. :V

That's the max fuel pump capacity, not quite the same as actual fuel consumption. Actual fuel consumption: Standard atmosphere on the left, standard atmosphere +10° C on the right. At Mach 1.1 on the deck, ~19% of internal fuel (4476 kg as per Leatherneck's manual) works out to about 850 kg/minute or 51 metric tons per hour. That's only 112,400 lbs/hour. Fuel consumption is lower at higher altitudes; doing Mach 1.6 at 8km MSL it's down to only 12%/minute. I have no idea how much the F110 drinks at full afterburner, but I'd bet a pretty hefty sum it's one heck of a lot less :V

Yes, and it's also mentioned somewhere (I think in the aerodynamics compendium?) that the AJ 37 is considerably draggier than the Draken is in most situations but especially in level flight (not surprising if you look at a Draken from the front - it's really thin), so you slow down faster when coming out of afterburner too. A clean Draken can easily break the sound barrier in level flight on just dry thrust at altitude, something that is definitely impossible on the Viggen. Then again a Draken without drop tanks at military power has an endurance of maybe 40 minutes, and that's at high altitude... edit: also, to clarify, Mach 0.55 is distance-economical cruise speed at sea level. It gradually increases with altitude up to Mach 0.9 around 7-8km MSL or somewhere around there.

Glad you liked it :] For a more relevant and correct comparison with other aircraft of the period: according to the F-14D flight manual, the GE-F110-400, which is almost 20 years younger, starts at 61 kN static dry thrust installed in the aircraft. The RM8A cranks out 65.6 kN in the test rig and does 55 kN installed in the aircraft at M 0.3, so eyeballing the thrust diagram let's say 60kN-ish static in the aircraft, which is a very conveniently close figure. Going from there to Mach 0.9 at sea level in full afterburner, the F110's thrust more than doubles to 134 kN, but in the same conditions the RM8A is now up to 145 kN. It's pretty interesting to see that the mid-60's airline engine conversion not only keeps up but actually edges ahead as far as thrust goes, but the F110 is a bit lighter and smaller and I bet it has advantages in other areas (like avoiding compressor stalls at high alpha, for example...). And of course the F-14 is cheating and has two of the things while not even coming close to twice the Viggen's mass.

It has come to my attention that some people consider stage 2 of the Viggen's afterburner to be lagom. That's a very Swedish opinion to have, but it is also wrong and offensive to me and I will fight you about it. So, let's talk about afterburners. Many aircraft have them. They are useful, since in aircraft of the Viggen's era they tend to give about a 50 to 60% increase in thrust over what's available at full military power (to be clear, I'm talking nominal static thrust here), and in some cases reaching up to a 70% increase over dry thrust, and things like the MiG-21's emergency afterburner can go up to 75% if I'm not mistaken. Now, on dry thrust the AJ(S)37 is slightly underpowered compared to its contemporaries, especially the twin engined ones like the F-111 and the F-4. It has a max takeoff weight (MTOW) of just under 19 tons, while the RM8A has a nominal dry static thrust of 65.6 kN, which means around 3.5 kilonewtons per ton. In other words, that's a thrust to weight ratio of about 0.35:1, where the contemporaries tended to approach 0.4 and had a bigger payload margin to boot. But what about the afterburner? Yes... The Viggen's afterburner, on the ground, at a standstill in a test rig, tops out at a nominal thrust of 115.6 kN, which is a 76% increase over max dry thrust, and unlike on the MiG-21 which reaches this neighborhood only while on a rapidly ticking overheating clock, the Viggen's afterburner will stay at this throttle level for as long as you have fuel to feed it (which, granted, isn't very long, but we'll get there). It doesn't stop there, though. Let us look at a thrust (and thrust to drag) chart, because everyone loves charts, right? Standard atmospheric conditions (ISA), at sea level. On the vertical axis here, we have thrust in kilonewtons - if you don't speak metric, 10 kN is 2248 lbf, or approximately the force required to lift one metric ton at sea level. On the horizontal axis, Mach number. The afterburner stages are the shaded areas labeled zon 1, 2 and 3, with max dry thrust being the black line that follows the bottom of stage 1. The curved black lines marked 1-4 are total drag in level flight with four different external stores loadout "templates" where 1 is lightest/least draggy (drop tank plus something light/small like AIM-9's) and 4 is heaviest/most draggy (16x120kg bombs plus drop tank, basically). Similarly, the line marked R is total drag with a clean aircraft. Where those lines cross a particular thrust setting, that's where the equilibrium airspeed for that loadout and thrust setting is - in order words, that's the speed where the aircraft won't accelerate further because thrust pushing you forward is balanced out by the drag holding you back. Now, a jet engine works according to the principles of Newton's third law, or the conservation of momentum. It takes in air, accelerates it and shoots it out the back, and the equal and opposite reaction pushes it forward (a jet engine was called a "rea(ktions)motor" or "reaction engine" in Swedish in the 1940's and 50's). As your airspeed increases, the relative velocity of the air you're shooting out behind you decreases, and so we see what's happening in the bottom of the chart, at dry thrust and min zone 1: by the time we're up to Mach 0.55 (distance-economical airspeed at sea level), dry thrust in the real aircraft is down to under 50 kN from the 65 we had at a standstill in the test rig. In the transonic region (Mach 0.9 and above), dry thrust - and thrust in zone 1 afterburner - starts dropping sharply. However, in the upper part of the chart, there's something else going on. Recall that the RM8A is based on an early 1960's airliner turbofan that powered things like the DC-9, Boeing 727, and early 737's. That means it has a relatively high bypass ratio for a fighter engine, very close to 1:1, which in turn means that the afterburner has a lot of cold, fresh air to burn and accelerate. The faster you go, the more air it has to work with, and the more thrust it produces. From the chart we can see that in zone 1, as airspeed grows, this is just enough to outweigh the loss of thrust from the regular engine. In zone 2, the added thrust from the afterburner grows faster than the dry thrust drops, and total thrust now increases slightly with airspeed. In zone 3, though, and especially at max zone 3, that's where the fun begins. At sea level and max zone 3, increasing your airspeed by 0.1 Mach also increases your total thrust by ~5-7% throughout the entire speed envelope. The test rig maximum of 115kN is passed at around Mach 0.52, and at Mach 0.9 you're up to around 145 kN, which is over three times the dry thrust you'd have at that airspeed. Remember that figure of a typical increase of 50-70% over dry thrust? That was a in the test rig on the ground, so the numbers aren't really comparable, but it's still amusing to note that max zone 2 gets you 70% over dry thrust at Mach 0.5. Max zone 3 in that situation is like adding another afterburner on top of the regular afterburner, because max zone 3 gives you another 60 percentage points, topping out at 130% over dry thrust at that same Mach number. All of this comes at the price of massive fuel consumption, of course (over 15% of internal fuel per minute is easily achievable), but now I'm finally starting to get to the point. I've seen some people limit themselves to zone 2, presumably because they think that this will save them fuel. In many cases this simply isn't true. Yes, zones 1 and 2 use less fuel per minute, but you gotta ask yourself why you're throttling up. A lot of the time, it's simply because "I want to go faster". Well, zone 3 also wants you to go faster, as indicated by the fact that it gives you more fun (thrust) the faster you go, and if you are nice to the aircraft she will also be nice to you. Let's have a look at an acceleration chart: Standard atmospheric conditions, sea level, loadout in group 3 (roughly speaking, four rocket pods and a drop tank), full fuel minus 275 kg to account for takeoff and initial acceleration up to Mach 0.55. On the horizontal axis (way down at the bottom), Mach number. Vertically, we have three different graphs, where the lines marked "MAX SL" is max dry thrust and the other three are max afterburner zone 1/2/3 respectively. At the top, time taken to reach the given Mach number, in minutes. In the middle, fuel used, in percentage points (full internal fuel is around 100-106%). At the bottom, distance covered over the ground, in kilometers. We can tell two important things from this diagram. First, acceleration in max zone 3 is hilarious. Even with this relatively heavy loadout (and full fuel, too) you go from M 0.55 to M 0.8 in about 15 seconds. Additionally, the Mach number/time relation is almost linear all the way up to the transonic region because the thrust increases almost as fast as the drag does. Well, we already kinda knew that. Second, and more importantly, accelerating in max zone 2 is no more fuel efficient than doing it in zone 3. In fact, it rapidly becomes less fuel efficient. Zone 1 (or even max dry thrust) can be more fuel efficient if you're going slow and the desired difference in speeds is small, but if all you're thinking is "man I wish I was going faster right now", just kick it straight into max zone 3 - the shorter time needed for the acceleration outweighs the higher fuel consumption. The differences are smaller on a lightly loaded aircraft, but zone 2 is insignificantly more fuel efficient for acceleration even on a clean aircraft. On heavier aircraft or on a hot and humid day, the differences are bigger, in zone 3's favor. At higher altitudes, say 5-6km and above, max zone 3 is almost always the most fuel efficient (exception for small speed changes with light loadouts). If you reach the desired speed and want to maintain it, then you obviously throttle down, but for getting there just use max zone 3. The same thing goes for climbing, but there you also have to consider why you're climbing. If you just want to get high, right now, max zone 3 is almost always the most fuel efficient (or insignificantly less fuel efficient than the other options) and it gets you there really fast. If you want to climb because you're going to do a long ferry flight and want to take advantage of the better fuel economy per kilometer at high altitude, it's better to climb dry or in zone 1 because you'll spend about the same amount of fuel as in zone 3 but also cover a long distance while doing it. The exception to this rule is takeoff, where zone 2 is generally a good compromise between thrust and fuel consumption, except with very heavy loadouts. Well, as long as you have runway to spare, that is... tl;dr: zone 1 is useful for making noise and keeping formation at high subsonic speeds, zone 2 is rarely useful, zone 3 is the FARA zone

Been asked before, and answered: https://forums.eagle.ru/showpost.php?p=3005508&postcount=59

As Farks says, what you want is the publication Taktiska anvisningar för attackförband, or "Tactical advisory for strike squadrons". For the Viggen's predecessor, the Lansen, these manuals have been declassified and you have one there at Farks' link. I requested to have a later version (from the early 1980's, IIRC) declassified about half a year ago but the mills at the national archives grind very slowly sometimes. On a high level the tactics with the Viggen remained similar to the ones used on the Lansen, but due to the improvements on the newer aircraft I believe the Viggen would have enabled more independent tactics and above all much more aggressive flight profiles because of its higher speed and acceleration. e: this anecdote may be of interest as well

Okay, so the story goes like this. When the Viggen still is in the planning stage, its only guided weapon and only anti-ship weapon is the rb 04. Which is fine, but it can only be used in open sea because of the sorta primitive seeker and navigation systems. So, a secondary weapon is needed for archipelagoes and beach landings and such things and it would be nice if it could do double duty for other strategic targets. Enter the rb 05A, which comes into service at the same time as the aircraft itself, in 1972. Now, what also happens in 1972 is that this new hot thing called the AGM-65 enters service in the US. TV seeker, so fancy! The SwAF wants in on that. Saab proposes an updated rb 05 with a new seeker similar to the one on the Maverick, but for economical reasons the air force ends up buying the AGM-65A only a few years later (IIRC deal signed in 1977). Also, you can "jam" the AGM-65 by using smoke, and IIRC the TV seeker on the A model had some problems with very high brightness environments such as snow-covered fields on a sunny late winter day and glittery seas etc, so the rb 05 remained relevant as a secondary guided weapon.

From memory I'm 95% certain you can configure all those things on the rb 15F. I am certain it does have cruise altitude settable between something like 2000 meters and "waveheight adaptive".

If there had been more money in the 80's and less focus on the Gripen, we could've gotten this truly multi-role Viggen instead, at least ten years earlier: Among other things, it would have included the same kind of data link as the JA 37 had, but for ground targets too. Full document here, IMG 3865 and on, if you want to dive deeper in the alt-hist swamp. There was a JA37B2 proposal too which was less comprehensive and just added the rb 15.