Machalot

Did you notice that starting a few seconds into the track, you are inputting opposing rudder and stick? You input left rudder along with strong right stick -- a recipe for unpredictable flight. There's no reason to use the rudder in flight. For most of the track your stick was hard to the right. Let go of both controls and let the aircraft settle. As for the airspeed, note that the 4 mark on the airspeed indicator is 400 km/h, which is only 216 knots. That is not a good speed for maneuvering, and a delta-wing aircraft like the Viggen has high drag when flying at low speed and high angle of attack. You also exceeded 20 deg angle of attack many times during this flight, which is prohibited and will cause big problems (shown on the gauge just left and below the HUD). Anything above 17 deg comes with a high chance of compressor stall, which also happened in your flight (sounds like a hammer accompanied with flashing Master Warning and tones ["HUVUDVARNING"]). Compressor stalls drastically reduce engine power and are deadly at low altitude. My advice to you is to lay off the rudder, keep your airspeed above 550 km/h except when approaching an airfield to land, and take it easy on the stick inputs. Spend some time doing gentle maneuvers with simple, single-axis inputs (pitch only, roll only, etc.), and get a sense of how to fly without pegging the angle of attack so hard. If you experience a compressor stall, reduce the angle of attack below 10 deg by letting go of the pull or gently pushing forward on the stick, throttle back to clear the stall, and then go to max power, wait for thrust to come back, and gently pull up.

Generally if you take damage, all bets are off. I've had damage where my aircraft wouldn't even retain missiles on pylons -- as soon as rearming was complete they would just fall through the ground. So is this issue reproducible or was it just in one mission where you were damaged?

I wonder if this is also supposed to include the use of the IR Missile Fast Select.

A series of me shooting rockets at an Ural truck with a ZU-23 AAA cannon in the back, taken by my pal Arctic in the chilly early morning on Kola.

I pinged BN and he replied within 5 minutes!

@BIGNEWY Any acknowledgement or status on this bug? Thanks.

The default functions of those keybinds has been changed to that of the real aircraft, which is documented in TOViper's post above. But luckily, new "Toggle" keybinds have also been added that function like the old way. Press once to activate, and again to deactivate.

Sure would be nice if this filter could be set on by default for a night start. The unfiltered radar is blinding!

A fix on an M point ("Target fix") changes the coordinates of that point only, without making any other changes to your navigation system. A fix on a B or Bx point ("Navigation fix") doesn't change anything about the waypoint, rather it overwrites your current navigation system coordinates to match the waypoint. You're telling the navigation computer, "Wherever I thought I was, forget about it, I am actually at the waypoint." This moves your navigation state onto the current waypoint so it is now 0 km away. From your perspective this waypoint appears to shift onto you, and the entire set of waypoints shifts accordingly. The effect is exactly the same as the automatic TERNAV fixes performed by the CK37 using radar altimeter data. (If you do a radar fix instead of a flyover fix, everything here is still true but is applied with an additional offset equal on the radar cursor position.) The E is not a type of point, it's an intermediate state that is displayed once you initiate the fix process (trigger to T1) until you finalize it (trigger TV). Read the manual starting at p. 264. Just as a point of forum etiquette, it's better to start a new thread of your own and link to this one if necessary, rather than resurrect a 7 year old thread. Hope this helps!

Interesting thing about the mass table in that source is that the propellant and all expendables are (978 lbm - 602 lbm ) / (2.2 lbm/kg) = 171 kg compared to 163 kg in the DCS lua. (Are there other expendables like coolant or hydraulic fluid? I wouldn't expect motor insulation and nozzle erosion to account for 8 kg.) The public source also suggests an Isp of 97,000 lbf-s / 376 lbf = 258 s, compared to (13,595 N * 27 s) / 163 kg = 230 s for DCS. The problem is we don't know what altitude that 97,000 lb-s total impulse and 4,000 lbf thrust pertain to. In Tavarish's table it would be somewhere around 30,000 ft. If 4,000 lbf is the average thrust, it suggests a nominal burn time of 97,000 lbf-s / 4,000 lbf = 24.25 s.

ELINT has had issues for a while. I'm not sure exactly what's wrong with it. The kneeboard maps are not connected to the Viggen's cartridge system unfortunately. Only the waypoint listing on the first two pages.

For a bit more background on the effects of propellant temperature, see chart 7 here: https://web.stanford.edu/~cantwell/AA284A_Course_Material/Karabeyoglu AA 284A Lectures/AA284a_Lecture11.pdf

The motor propellant temperature starts at roughly sea level ambient where it was stored. It takes hours and hours for the propellant to equilibrate with the outside temperature, certainly not within a single F-14 sortie.

The DCS missile may well have too much induced drag, if that is what's causing the 7 second period of very low acceleration I mentioned.

The NASA figure caption says that trajectory was optimized for maximum Mach number, which is not what the DCS missile guidance is optimized for. Also note in your DCS data the missile has a little hiccup between 5 and 10 sec after launch, increasing only 0.1 Mach over 7 sec, while its average acceleration over the rest of the burn is more like 0.5 Mach every 5 sec (0.1 Mach/sec), and only exceeds Mach 3 nearly 18 sec after launch. The NASA sim has no such lull period, reaching Mach 3 within 10 sec or so, which shows (no surprise) that its guidance (and possibly the aerodynamic model) is better optimized for the initial pull up. With a pull-up guidance optimization, I think the DCS missile would gain roughly 0.5 peak Mach -- but this is not necessarily the guidance the missile should use tactically.

First, I would encourage everyone on this thread to stop using the term "NASA test". They ran simulations only, no tests. Second, NASA used publicly available data, no doubt full of estimates and assumptions, along with an in-house trajectory optimizer to fly "zero-lift trajectories ... with no missile guidance (fixed fins)". When I contacted the lead author through a mutual acquaintance to ask for more details, he described the results as "far from being definitive."

NASA used publicly available data.

For some reason, somebody at HB or ED decided to simplify the thrust model by setting the nozzle exit area to 1 square millimeter, effectively zero. Here's the readout from Quaggles' DCS LUA datamine, with a little searching: ./_G/rockets/AIM_54C_Mk47.lua: nozzle_exit_area = 1e-06, ./_G/rockets/AIM_54A_Mk47.lua: nozzle_exit_area = 1e-06, ./_G/rockets/AIM_54A_Mk60.lua: nozzle_exit_area = 1e-06, ./_G/rockets/AIM_54C_Mk60.lua: nozzle_exit_area = 1e-06, ./_G/rockets/AIM_54.lua: nozzle_exit_area = 1e-06,

The thrust variation with altitude is caused by the ambient atmospheric pressure acting on the nozzle exit area. If I remember correctly, the AIM-54 is modeled in DCS as having zero nozzle exit area, so the the pressure variation doesn't affect the delivered thrust at all. I believe if you were to change the nozzle exit area you would see a change in thrust as shown in the figure.

Are we just stuck without the ability to tune to airfields above 72 forever?

Press T1, then use the radar stick.

I don't have the same problem. Can you check if there's a cartridge with any non-standard characters in the name? Typically people who use unusual punctuation or non-English letters have this issue. Try deleting any such cartridge file from your Saved Games folder.

A minor typo, "the missiles has an operational range". Are you sure about the word "immediately" or is there a min range or min time delay before it will start locking targets? I would expect some kind of safety minimums, and maybe a warmup time for the radar.

Is it true that the engine must be running to power the radar? The engine powers a generator, and the radar is not powered by a battery?

Just to clarify, this means 20 km in front of the missile as it flies forward, not only when it is launched.