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Everything posted by outbaxx

  1. It’s a recommended limit, the charts show that the afterburner zoneIII have enough power to accelerate further. But the real limit seem to be the fuel pumps, it can’t keep up with the fuel needed for the engine. “Flying at M1.1 will deplete the fuel within 10minutes, but the fuel feed won’t allow that, the engine will light out before the fuel is empty” So perhaps the question would be for how long can the pumps keep up before a engine light out? /F
  2. You are not supposed to fly that fast at sea level in the Viggen. You need to fly it realistic. /F
  3. Well, for anyone thinking about the Nano Every for your RS485 slave project, to get it to work you need to write Slave-code for the 4809, I wouldn’t even know where to start. Regards F
  4. Remembered that there is a DCSBIOS_DEFAULT_SERIAL... That will compile the sketch, haven’t had time to test it yet though.
  5. Has anyone used the Every for your DCS-Bios projects? It’s not compiling for me, the error log states something about tx/rx in the DCS-bios library. Tried with both serial and rs485. Anyway, reason I wanted these was the extra memory to be used with my Datapanel display, it works with a nano but I get low memory warning. So, is there support for this board? Regards F
  6. Only reason I can think of is that there is a g-limit for firing RB from R7, it’s 0-3.5G. And: So perhaps these limits is the reason? It’s hard to do a2a with that :)
  7. Ah, thanks, man I feel stupid, it’s an unsigned int... Thanks :)
  8. Hi guys Can someone please explain how the g_iInitIntervalCounter in the code snippets posted in this thread work? It’s set to 0, then in the if statement it’s ++ and check if it’s 0 and if so run pollcontrol ? I just don’t get what it counts, and why we check if it’s zero? Regards f
  9. DCS-BIOS over RS485 Windows update? Today I was going to do a fast test with a new solenoid, connected and started the sim, but none of the panels I have worked, the tx light on the master flashed but no response. Disconnected all network cables to the master and tried with only one panel, nothing. Got prompted about a windows update, pressed later. Loaded stand alone code to one panel, that worked, crap, master might be broken... Windows restarts automagic and updates and now everything works again? Could the windows update be blocking the transmission from the master but not a stand alone panel? I have no idea but I didn’t do anything during the update, it just started to work again.
  10. bool power_is_on; void onMainElectricPowerChange(unsigned in newValue) { power_is_on = newValue; } DcsBios::IntegerBuffer MainElectricPowerBuffer(0x..., 0x...., 00, onMainElectricPowerChange); Then on backlight change check if power is on or not and turn power on if so and so on. This is what I use to check if power is on etc to make my solenoid for my start switch in the Viggen to engage only when all the needed switches is in the correct position.
  11. It’s a DCS thing, and perhaps the default DCS code isn’t up to par with the Viggens demand :) Maybe if the Viggen got a dedicated ground handling code but I guess that’s not a 5minute job. My workaround solution was to set Y saturation to 50 and just use one brake axis for both wheels. This means I’ve lost the ability to brake left or right side but so far I have not found that I actually miss that. I can land and not skid off the runway at least :)
  12. It did work one update ago at least.
  13. Yes, you are correct, and I found these two: Describing the trim angle for 1G (level flight?) at height 1km and as I understand it show that there should be about 1degree up trim at M0.8 for a clean aircraft?
  14. No, I fly almost only fly with a clean aircraft so I start with 0 trim. I guess I have 2-3 up trim at M0.8. But I thought I would have some down trim when I read the picture above.
  15. The title is : The Saab 37 Viggen. The development of a new multi purpose military aircraft for the Swedish Airforce 1952-1971 Author: Krister Karling So it’s the same author as the compendium mentioned above. Can’t say for sure but as I interpreted the text it’s the whole clean aircraft. There are graphs for aircraft with wing ordinance and for aircraft with center placed ordinance but they are the same up to M0.8 where the curves start to differ. But I’m only interested in the M0-0.8 regime where there is a positive pitch moment at alpha 0 but I need to trim nose up to go level flight and I don’t understand why.
  16. Flight model of the Viggen This is the image I looked at. I have no aerodynamic schooling so I assumed positive moment meant nose up :) But if it’s like you say, then we should have a nose down up to M0.8 then a large nose up followed by a a nose down to about M1.3 and then a raising nose again? (Edit: someone answered the thread and said that positive meant nose down but I can’t see that post now?) The image show the momentum at alpha 0 so it’s not an absolute truth off course. Regards F
  17. One thing I have a hard time wrapping my head around is that when accelerating after takeoff (M0-0.8) the Viggen has a “nose down momentum”, I have to stick aft or trim up or it will fly into the ground. Reading a book about the development of the Viggen there is a picture of the zero moment Mach characteristic and that show a positive zero moment at M0-0.8 (Cm 0.003-ish), then there is a steep negative moment at 0.8-0.9 (Cm -0.009 to -0.01) followed by a fast positive at M1.0 (Cm 0.005 to 0.006) and then a sloping curve where at M1.3 the Cm is negative again. (In DCS over M0.8 the behavior is what I expect it to be) The problem I have is that I don’t understand why the Viggen in DCS wants to dive below M0.8 if the zero moment is positive? Shouldn’t it be the other way around? A small nose up moment? Regards F
  18. This is how interpret it when reading the pilot manual too. And if you press it in SPAK you will disconnect SPAK.
  19. What ive read it is working very good with the exception when decelerating fast from supersonic because the “series trim” take 15sec to go from high speed to low speed and the pitch gearing will give more elevator deflection than it “should”. The pitch gearing at speed 0 give 22deg elevator but at 850km/h it will only give 8.7degress elevator with the stick full aft. Above 850 we are in “high speed” and full aft will give 11.8deg. And those extra degrees is what is causing the high G when decelerating fast from supersonic to about M0.8.
  20. I was under the impression that using SPAK would eliminate such behavior, that when in SPAK if you let say pull 25% aft you will have the same amount of G regardless what speed or altitude you’re at, it’s called “stickforce per G”. Why you can pull 12g is that the trim can’t keep up when you decelerate fast from supersonic, and that peak is around M0.8. So you shouldn’t be able to pull that high if you are accelerating through M0.8 if I understand it correctly, because the trim is still in subsonic. At M1.1 the servos aren’t strong enough to pull that high so no, it can’t do that, not according to the Max G charts anyway.
  21. What about the elevator/aileron effect? Could that be too small at lower speeds? I often “feel” like the effect is exaggerated, that I get max G before I have the stick full aft for example. But perhaps it’s too small during the take off run?
  22. I think you were on to something when you talked about 0 alpha and speed. I had time to do some take offs today and rotated at 280-ish km/h both with Mil and AB and i had a much smoother rotation. If I try to rotate at 240-250 with full AB, I almost always end up over rotating and get a high alpha warning. The nose lift so fast perhaps due to a combination of acceleration, alpha and lift coefficients that I have no chance to stop it before I over rotate, even if I release the stick as soon as I see the rotation it will continue and I have to do stick fwd to compensate. Perhaps the tweaking has to be done in the speed/alpha/lift section but that might have side effects on its own?
  23. Hi @15°C, mil power 15000kg ~ 280km/h 16000kg ~ 290km/h 17000kg ~ 295km/h I’ve had thoughts like you about the main gears but I’m not sure, been awhile but when taking off with Mil power I think has a smoother rotation than Z2 or 3, could be the low acceleration in Mil compared to afterburner but the resistance in the main gears would be the same? Could be some some “ground handling” code that doesn’t transition smooth to “airborne”, I only have the AJS37 so I can’t compare to any other fast aircraft if they are the same during take off on different weights. Why I say this about “ground vs air” is that when on landing with aerodynamic braking the loss of lift is also very sudden, but that is just a “feel” too, can’t say it’s wrong or just me doing something wrong. Me: -This doesn’t “feel” right. Truth: -Your “feel” probably suck. Me: -Need to post a question/statement. Truth: -Please don’t Me: -posting anyway ;) Regards F
  24. And it seems to be correct, you should flare when landing with α12 or weight over 14000kg. Even landing with α15.5 and weight under 14kkg there’s a dip depending on weight. perhaps if you are really really light weight there might not be a noticeable dip?
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