Heatblur: AJS-37 Viggen

This thread has lead to the most satisfying tangents.

So does the radar not have a mode for Air to Ground Ranging?

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What do you think this is…a MiG-21??

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or an F/A-18, or an F-14, or an F-111, or an F-16, or a Mirage-2000, or a Tornado, or an A-6. or an A-7.

I’ll leave…

:door:

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Imperial Scum!

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Check page 280 of the Viggen beta manual.

“In mode ANF the radar will range the distance to the target if the triangulated range is about less than or equal to 15310.6 cubits.”

Note 1 : There’s more instances where it is used but I got lazy of typing the manual verbatim.

Note 2: Unit of measure for range converted from being sub-standard/boring to one more interesting.

Note 3: Using the radar range measurement for IP update / INS fix is a pretty vital element of the Viggen’s system suite.

2992 if we are above the transition altitude, what you think we take off like that?

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So what I’m seeing here is either @einsteinEP or SAAB are a big fat phony, and we shouldn’t need QFE.

No, I am convinced that that is very much a Jeremy Clarkson meets Team America affair…

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I just eyeball it. When I see my FO’s knuckles go white…I ease in to the flare. Works nearly every time. Of course…no FO in the Viggen. :thinking: …gonna need a wingman to fly close formation.

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Skimming the rest of that section seems to indicate there’s logic a little more involved than “IS RADAR ON, USE RADAR FIX RANGE, IF NO, USE ALTITUDE MEASUREMENT.”

On top of that, cross-correlating @EinsteinEP’s screenshots with Page 296 of the Viggen manual, I don’t recognize the HUD symbology with what’s shown as the step-by-step progression for level bombing. Not sure if that’s a bug or if that’s a switch mishap.

EDIT: TO BE FAIR, listed in the procedure as part of your ingress checklist is “SET ALTIMETER PRESSURE (QFE)”, so it’s probably important.

From previous reading of the manual that I’ve done I think I’d comment that everything in the Viggen seems extremely specific- You want to do attack X with weapon system Y using parameter Z, make sure your systems are configured like so, then follow this very deterministic procedure. Pretty different from what I’m accustomed to from flying the Viper in BMS or Hawg in DCS.

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Yeah, it’s not as versatile as its more modern counterparts. The Viggen was more like a classic bomber. Go there and drop your ordinance. Try to return home. You don’t see a Viggen loitering for targets of opportunity. :wink:

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It does – DYK-Precision seems to work pretty well, and there are other modes that use precision ranging with the radar (more testing to do still) – but the radar is not used in all A2G deliveries.

Note my impressions are all based on my interpretation of the Leatherneck Sims manual and a promotional version of the Viggen module, which is being updated nightly. Before we write off Saab as making things difficult just to make things difficult, let’s let the WIP dust settle.

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stands on the soap box

So your accuracy when using anything that has “Constantly Computed” or synonym in the title is going to be determined by the accuracy of the information you’re feeding into the formula. Every aircraft has a hierarchy of sensors that provide varying levels of precision, it’s up to the pilot to decide which to use.

Referencing the standard of the Lawndart, it’s hierarchy would go something like TGP->FCR->GPS->RALT->BALT->INS.

As a pilot, you want to use the TGP to des your target as it offers effective VID and accurate fix via a laser. Failing that, the radar is your second best, which should be as accurate, but harder to ID the target. If that fails, you might use GPS depending on the accuracy of your local map area. Or Radar alt depending on the terrain, etc. etc.

The Viggen sensors seem like it’s going to be FCR->RALT->BALT.

So I was confused when I heard baro being used as the primary drop metric when there was, seemingly a more accurate alternative. I wasn’t sure if this was for mission reasons, or if there was other Swedish shenanigans at play.

steps off of soap box

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Okay that’s it, no more soap in the showers if all you guys do is stand on the boxes anyway… What’s next, racing them downhill?! :wink:

I prefer blocks of pine wood.

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Codes in action… must see codes…

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I’ll see what I can do!

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Hey @EinsteinEP!

Would you be so kind and test the DYK-ANF mode for us? If possible,with a deliberatly faulty set-up barometric altimeter. It took some digging, but according to page 281 of the manual the ANF mode actually allows the radar to collect range data. The manual even states this is by far the most superior way of having hopes of hitting a target on inclined ground on the next page.

According to some other place of the manual the DYK-NAV mode allows calculation based on RALT triangulation. It would be very sweet if you could try that as well, again with a faulty BALT setup. If you have time for any more of my requests, it’d be sweet if you could:

  • Comment on ease of use of ANF versus NAV in the DYK mode.
  • Comment on accuracy of ANF versus NAV on targets on virtually flat terrain.
  • Comment on accuracy of ANF versus NAV on targets on hilled terrain (I can already predict the outcome but it’d be great to actually see how much worse NAV perfoms against ANF in this situation).

Lastly, it’d be great to see a CCIP drop and the corresponding HUD symbology :smiley:

Remember that the Viggen I’m flying is pre-pre-release and should not be considered fully representative of the final product. I’m loving testing it out and sharing it with you folks, but this model and my impressions of it should not be used to characterize Leatherneck’s implementation, only its potential.

That said, DYK-NAV does seem much more accurate. I haven’t deliberately tested it with bad QFE settings, but my deliveries with that mode have been more on target than Level. The testing ground for these shots were flat ground (an island near POTI and the X runway near Kobuleti). I’ll look into experimenting with hilly/sloping terrain.

Also, if by “CCIP” you’re referring to dropping high-drag bomb in PLAN/NAV, I already have some pics of the symbology and will post them later tonight. They’ll have the WIP caveat, of course. The fun/scary thing about that mode is you have to be LOW to drop them.

I was also planning on looking at all the bombing modes, as well as Rb04, Rb15, and BK90 deliveries. That, plus some approaches and I’ll probably be out of time, but leave me with some specific requests and I’ll see what I can do.

Near blind do I have to get up here and explain HAT hierarchies again :stuck_out_tongue:

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