This works for me- I’ve been neck-deep in schoolwork, so now that the semester is over, I’ll actually have time to do stuff. And I’m looking forward to taking a much deeper dive into the computer anyway.
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So what is the correct procedure to make sure that my Nav settings are all correct?
Last night I tried doing the ‘Nav fix’ at the (far) end of the runway (after takeoff) and must have messed it up because my target point was somewhat south of where it should have been.
On the next mission, after lining up just in front of the runway numbers (they were in front of me), I set the Master Mode to Nav mode and hit the ‘reference button’ and saw my compass (around the radar display) adjust. This time my target point was where I expected.
I read about people doing it at the far end of the runway after takeoff (hitting the reference button) but that never works for me.
Also, just for sanity sake … the Magnetic Declination Adjustment Knob. How do I know what to turn that to? It looks like a rotary that adjusts between +10/-10 degrees but I can not see an indication on the knob to tell what it is set to. How do I know how much to turn it? There must be some indicator that lets me know what it is affecting and i am missing it 
.
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Ok. So reading here: Magnetic declination - Bugs and Problems - ED Forums
And the Magnetic Declination knob is not really supposed to do anything in the sim. It is ‘magic’
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The aircraft must be in NAV mode 2 minutes before taxi out IIRC according to procedures though I am not 100% sure if I remember that from real life procedures… But keep it in NAV mode, and align on the runway! It will presume you are at Ls anyway until a certain altitude has been reached!
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The error in the system seems to add up fairly rapidly - supposedly the terra nav is supposed to keep it well aligned but then you go over long stretches of water…there is the Land/Sea switch… which I try to remember to switch on. I haven’t done a “study” to see of you are more accurate over land or what not…I suspect you are.
What I have been doing that seems to work well enough is to get a radar nav update for the last WP before I start my attack run. I like using a nice land/water interface like a peninsula or river inlet, although you can get good returns from big buildings. So I keep my speed down to under M0.6 as I approach the WP - tune the depression angle and contrast on the radar starting at about 30 km out. Inside 15 km (lowest zoom on the radar) I go to T0 and adjust - hit TV around 5 km. That give you enough time to realign yourself for the WP turn. From there, depending on how long your run in is, you should be well within the ball park at the target.
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Hitting the reference button on lineup basically tells the computer that whatever heading you have at that moment is actually the runway centerline to correct any slight deviations. It’s smart enough if you take off from the other end of the runway to figure that out and not freak out when you update.
The nav fix over the end of the runway, requires a nav point located at the end of the runway to update. Otherwise you’re updating your current active nav point to the end of the runway which will be way off.
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Times have been hectic, as I’m sure it has been for many. I was supposed to graduate on July the 10th. Now that I got a little assurance I’m still on track to do so despite not being able to do as much research as I could have done without an ongoing global pandemic I took a little break from thesis writing and flew my Viggen
I flew the viggen extensively when she was first released. I am especially fond of the Interdiction mission you can find included with her. In fact I’m so fond of it I modified that mission so it could be flown with many different airframes, it’s especially cool with a harrier at night!
https://www.youtube.com/watch?v=ScE09SQRc4s
I look forward to revisiting it. First, I had to get refamiliarized with the airframe. I gave this entire thread a read ( am looking forward to trying the missions some of you guys made) and read Chuck’s guide front to back.
Start up went smooth, She’s pretty easy to get going. I always find it funny the RAT hangs out when the gears are down, slowly spinning at taxi velocity. Take-off went smoothly as well, and I flew a couple of waypoints to find my practice target, somewhere close a lake.
At this point I borked things up a little bit for myself. I wanted to transform waypoint 3 into target 3, but I forgot setting the selector to TAKT before doing so. This somehow put waypoint 3 over 400km away from me as I was messing with the controls. Luckily, the viggen has that air-to-ground radar, and the lake was soon found anyway.
Low level leg of the flight.
Decently accurate! Although most shots ended up long.
Found my airfield to land at, although I’m coming in a little fast.
Oof… That braking power is something else compared to the F-16. But no written-off airframes yet!
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Hitting the reference button should not be necessary in practice though. The computer will automatically figure out from which runway and direction you are taking off and update the heading in the navigation system by integrating aircraft heading during the take-off run. I think the manual input with the reference button is only necessary with strong crosswind and a wet runway, where a side-slip during take-off would introduce a faulty automatic heading fix.
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The key word being “yet”…I speak from some experience. 
My understanding ding is that you are supposed to get down to practically taxi speed with the reverse thrust before engaging braking.
One thing I have noticed is that using the rudder to keep centered while using heavy reverse thrust can be tricky. While I’ve never completely lost the jet I have done some wicked ground loops and one time bent a main mount. If this is accurate it might have something to do with the rudder and reverse thrust putting unusual force vectors in the tail area. (?) You can feel if it is starting to happen and can either drop to idle and apply rudder or lightly tap the toe brake to steer.
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Speaking of landing…an AAR.
So I built a mission in the PG where you launch from Sirri Island, attack a couple of ships with Rb-15s and return.
Nearby Aba Musa Island is enemy held and defended by ZU-23 emplacements.
After a successful attack I’m heading for home. I got behind my wingman–probably when I cut him loose because he was Bingo. So he’s up ahead somewhere.
I’m a little concerned because he will land first and I myself am at Bingo so don’t really have the gas to circle all that long while he lands and taxis. No worries, I’ll just land after him and since he (being an AI) has to go all the way down the runway before he turns around, I’ll just use the thrust reverse to stop around mid field.
As I go by Abu Musa I see some tracers heading my way and hear a couple of “plinks”…jink a bit and I’m good to go.
…but something just doesn’t feel right…hmmmm…
Sure enough Dash-2 is on short final as I start my line up. I go though my checklist:
Automatisk Fart Kontroll - (chuckle)…On
Gear - Down
Thrust Reverse Lever - Out
…the jet is decelerating and is controllable but something still does not feel right…
I finish the Checklist…
Master Switch - LANDN P/O
I come in a bit fast but make a nice landing - nose wheel down and forward throttle…nothing…no…wait…going faster? Check reverse thrust - the lever is out…is the light on? Throttle idle, cycle the reverse thrust lever, throttle up…going faster…
So now I’m about the mid field mark and not only do I probably not have room to stop but I’ve also got Mrt. Wingman, slowly taxiing down the runway ahead of me…what to do, what to do?
AFK off
Throttle full AB
I’ve angled to the side of the runway but…I pull up with the stall warning yelling at me - get the gear up fast and level out…I’m flying…
"OK…let’s take a look at things…hey what that light on the warning panel? "
A few thoughts on sim vs RL pilots:
I get the feeling from reading these forums that the real pilots in the group probably take a completely different attitude towards the illumination of a warning or caution light. First, they probably have memorized where the various important lights are located and don’t need a couple of minutes to squint at them. Second, they probably have some pre-planned procedures or check list items that they execute when a light illuminates.
For a purely sim pilot, like myself, the reaction is quite different. Upon seeing the light come on the initial reactions goes something like this, “Well…that’s odd. I don’t think I have seen that come on before. I wonder what it means? Let me take a look.” In this case, flying the Viggen, the lights are in Swedish, a language that I do not speak. “Hmmm…it appears to say something about a ‘BRA 24’…what could that be? ‘BRA’? Maybe it’s a women’s thing. I’ll just ignore it for now. Maybe it will go away.”
Think…aviate, navigate, communicate.
Aviate: No TR…I’m going to need a long runway and I don’t have much gas. So I turn SE and head for the UAE coast - hoping for one of those Int’l airports with the long runways - get the jet up around 1,500 m and set AFK (chuckle)
Navigate: Switch Master to NAV. Take a look at the chart - pick out what looks to be the closest - Dubai Int’l. Reset the Alternate to Dubai Int’l and get the direct healing on the HUD - steer towards it.
Communicate: Switch to Dubai Int’l and call inbound.
The fuel is going pretty low but I think I can make it to an upwind landing (will help slowing down). I make a good landing, speed brakes on and roll out, lightly pumping my toe brakes until I come to a stoop.
Aftermath:
The BRA < 24 was my low fuel light so…I actually did the right thing by ignoring it…after all I was already in "Land ASAP"mode.
An outside inspection of the aircraft showed some AAA holes around the Reverse Thrust mechanism area - it was evidently shot…figuratively and literally.
The Debrief report stated I had lost the back up AP…huh? Not sure but that may have contributed to the “didn’t feel right”
Anyway, it was fun!
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It is on the real jet too… In fact, reversing on landing is not recommended if SPAK mode can’t be engaged. SPAK autopilot (steering automat) is a bit like a damping mode for all axes.
I have my rudders on a hefty S curve because of how twitchy the Viggen is on the ground.
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anybody flew the Mjolnir campaign recently? What’s the status? I flew the second mission and did the show-of-force pass dropping the high-drag ordnance, but I got nothing but crickets and failed the mission.
Frankly I think the ground handling in DCS is a bit dubious. I have the impression that sometimes SPAK is not dampening but rather over-controlling rudder input. Have a look in the external view and compare the rudder movement by SPAK with your own input.
I also think it is rather strange that you can’t disable nose wheel steering. Touch down in a cross-wind with rudder input and you will get immediate nose wheel reaction. This welcomes disaster.
What is certainly wrong is the lack of any anti-skid braking in DCS which the real yet is supposed to have.
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I agree. The Viggen was designed to travel fast on the ground and according to friends of mine who have flown the real deal, it had great ground handling. It tracked straight at high speeds due to the inline main wheels.
The only caveat was when reversing, which generated an air cushion under the belly that reduced the load on the main wheels and increased the nosewheel load.
It certainly did when the module was new. It was addressed in an update, but I’m not sure they are done with it…?
You can’t.
The NWS is a direct link with the pedals. Full rudder input means 30° nosewheel angle, and that’s a lot! But, again, those inline mains kept it on the straight and narrow.
It does have a crude mechanical anti-brake lock. Each main wheel has it’s own mechanical inertia sensor that keeps it from locking up. It’s not like modern ABS computer braking systems that will modulate the brakes to keep you going straight. It will just keep the wheels from locking up. But this happens regularly in DCS, so something is off.
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Some real-life aircraft are like this, if the nose wheel doesn’t center at full strut extension.
In that case, rudder neutral before nose wheel touchdown prevents yaw excursions.
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Good point, @WarPig. The nose wheel steering is unloaded until the nose gear strut compresses.
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I just took the Viggen for a ride and when taxing at 10 kph, at the slightest touch on the pedals SPAK will spike with full rudder deflection, often being counteracted by full deflection in the opposite direction.
Frankly I wouldn’t expect much more adjustments on the Viggen. I had the impression that Heatblur has hardly worked on it anymore for some time now (Tomcat and all). I have filed a few bug reports over the years which didn’t go anywhere.
The VR pilot and RAT update this winter was a pleasant although long delayed update and I hope we will still get the engine sound update that was being talked about since release. Other than that I don’t expect anything else.
Yeah…what’s up with the RAT? Does it really just pop out? Why? It seems to do so on the ground where it is pretty useless…kind of reminds me of…
Seriously, what is it for?
I think that the idea is that it is out by default and held in by hydraulic pressure? So, if you lose hydraulics/power, it pops out without requiring any effort. May be simpler to design and maintain that way.
Let me quote the manual on the RAT!
Backup generator (ram air turbine)The backup generator is in the form of a mechanically controlled and hydraulically de-ployed ram air turbine mounted on the left side of the fuselage.The turbine is effective between airspeeds of 300 – 700 km/h. Speeds over 700 km/h may lead to damage of the RAT, and at speeds below 290 km/h no voltage is being generated.The RAT extends automatically when the nose wheel is depressed, and is retracted automat-ically on landing gear retraction, but is not connected as a power source unless required. On loss of power from the generator due to a failure, the RAT is automatically extended. The RAT can be manually extended with the RESERVSTRÖM (Backup power) switch