nairb121

Engine overspeeds by an extreme amount when advancing throttle to afterburner immediately after spawning in air. To reproduce: 1. Spawn in air with throttle in MIL or below. 2. Immediately advance throttle to MAX. 3. Engine hangs at ~85% RPM, temperature climbs rapidly. Afterburner does not light. 4. Reduce throttle to MIL. Engine increases to 100% and overshoots significantly, to almost 200% RPM, with excessive thrust and fuel consumption. 5. Engine after some time slows back to 100%. The duration of this overspeed seems to be proportional to the time held at MAX prior to reducing to MIL. I believe I have encountered this overspeed issue in other situations, but I have only been able to reproduce it in this manner. Track is attached. F-5 engine overspeed.trk

The -1 notes speed brake on approach variously as "as required" or "as desired", which suggests to me that its use is optional, either based on pilot preference or squadron procedures. Speed brake usage is not elaborated on further other than what is shown in the diagrams.

Note that this is for the manuevering flaps installed in the F-5E, E-1, and E-2, and the F-5F and F-1. The section on the AUTO flaps installed in the E-3 and F-2 is slightly different. I agree though that manually setting flaps up at best does nothing at low AoA, and at worst reduces the L/D ratio at high AoA, increasing speed loss rather than decreasing it, for a given turn outcome. The only times, in my opinion, that flaps should not be set to AUTO are in cruising or formation flight (UP or FXD depending on speed and weight), to avoid transient effects. Outside of emergency situations there is no need at all for any setting on the flap lever other than THUMB SW, as the flaps automatically reposition to FULL with the landing gear deployed.

Public-release unlimited distribution document linked below provides data on the F-5's longitudinal feel characteristics and loads, starting on page 151 (numbered in document as 122). Of particular note are the charts showing measured stick force per g at various speeds and configurations on 169-171 (numbered in document as 140-142). https://apps.dtic.mil/sti/pdfs/AD0738625.pdf

The F-15's artificial feel system isn't like a lot of other planes. The stick force per displacement doesn't change significantly based on airspeed - instead the stabilator linkage is geared to airspeed such that the stabilator deflection is reduced at higher airspeed for a given stick force/displacement, in order to maintain proportional force per g. Might be a little weirdness from the CAS but for the most part there should be very little change in the stick feel, only the response of the aircraft.

I'll send you a DM so we don't derail this thread any further.

Are you sure CLS2Sim is properly connecting to DCS? It should show in the CLS2Sim window, once you're in a mission, that it's connected and receiving information. Otherwise you'll need to check and make sure the DCS plugin is properly installed.

BrunnerDX is an external program that uses an Arduino to interface between DirectInput and CLS2Sim, allowing DCS's native force feedback to work with Brunner hardware. I've been using the CLS-E with CLS2Sim in DCS for a couple years, and have only now been able to test the native implementation via BrunnerDX. This is indeed the behavior of DCS's native FFB implementation.

It's a Brunner CLS-E. I normally use Brunner's CLS2Sim software, since Brunner doesn't natively support DirectInput FFB, but I recently got BrunnerDX working and wanted to try it out with the F-5E. Until this is fixed though, I'll probably just keep using CLS2Sim instead.

Here's my F-5 profile, you're welcome to give it a try if you like. F-5.zcs

CLS2Sim uses a vJoy device to receive FFB effects from DCS, that's how modules with FFB support (like the F-14 for example) can send shaker effects. It only does effects though, not stick position or force, which is why it uses its own internal trim rather than DCS's. The F-5's FFB implementation doesn't provide any shaker effects that I'm aware of, all it does as far as I know is basic recentering, trim, and the aileron limiter at 50% lateral deflection.

When flying the DCS F-5E with a force feedback stick, the forces on the stick remain constant for a given displacement regardless of airspeed. This is inaccurate - the F-5E has an artificial feel system which should provide longitudinal (pitch) stick forces proportional to g. Increased airspeed results in more g for a given deflection - therefore stick forces should be higher at greater airspeeds.

Sure. Testing it with settings as below, I couldn't tell any difference in the intensity. I clicked "Apply" after the changes, not sure if that matters or not. I also tried checking the "Manual control" box and clicking "Apply", then adjusting the knob on the controller, but again, I couldn't tell a difference. EDIT: I tried the Russian Gametrix software instead, and that seems to have fixed it. Thank you! However, I also realized during testing that motor zone 2 was not responding. I can't find any damaged or disconnected wires. I measured the voltage between the pins at that connection though, and measured 0 voltage with those motors in test. Zone 1 worked in test, and measured 9 volts at my current setting, so I don't believe it's a measurement error, or an issue with the wiring or motors. Is it feasible to repair this, or will the board need replaced?

I'm having some trouble adjusting the intensity on my Jetseat - I can't tell any difference between minimum and maximum setting in the Jetseat control panel, or in manual with the controller adjustment. Is this normal, or is something wrong?

Yeah, I definitely agree with you here. I get confused enough with the airspeed/stick pull/g relationship, CG stuff isn't something I have any desire to worry about. It wouldn't surprise me either if DCS inputs already accounted for that anyway.

G forces are not involved since no artificial feel is required for G forces in the real thing. I might not have worded this as clearly as possible. Most sources I've found seem to indicate "constant stick force per g". I ended up finding this patent, U.S. Patent #2661169, relating to early artificial feel systems (in this case, actually granted to Northrop Co.). Relevant quotes: nullIt also included this figure, showing stick force vs. deflection at various airspeeds: Although the aircraft configuration is different, and the mechanism had likely changed by the time the F-5 was designed, it seems reasonable to me that the overall design philosophy (i.e. constant force per g) would be maintained. I was unclear here as well, I meant fore-and-aft stick movement, i.e. pitch.

Aircraft with hydraulic boosted controls don't give the pilot direct feedback from the control surfaces, like mechanical linkages would. They generally include some system to simulate that "feel", referred to as "artificial feel". Without that feedback, it's difficult to accurately control the inputs you're making. So really, using FFB in DCS is artificial artificial feel. Unfortunately, my stick (Brunner CLS-E) doesn't support the DirectInput force feedback API (maybe it's time for me to pester them about it again), so I can't easily use ED's implementation. I'm mostly restricted to a force vs. deflection curve, with an additional multiplier based on airspeed. There are a few other variables, but I'm mostly trying to figure out how to dial in the airspeed multiplier curve. Educated guess or not, this is really helpful, since it at least gives me a starting point for looking into these systems. It looks to me like (at least for longitudinal controls) it's generally expected that stick force will be proportional to g. I might have to do some math at some point, but I think this should at least get me headed in the right direction.

Aircraft with hydraulically boosted flight controls are generally equipped with artificial feel, to give the pilot some feedback on their control inputs. I'm trying to get realistic behavior from my force feedback stick, but I'm having a hard time finding any specific info. I'm mostly wondering whether the feel system accounts for airspeed (increasing stick forces as the aircraft accelerates), or if it's just a static spring system. Does this vary between aircraft? Or between hydraulic and FBW? If there are any solid sources anyone can recommend for more info on this, I'd really appreciate it.

I think this would be an awesome module. First real multi-crew WW2 module (Mossie navigator isn't really very necessary), radar unlike anything else we have, remote turret... lots of unique features. Plus it served in both the European and Pacific theaters, and within our late-war DCS timeframe.

OK, mystery solved... After experimenting with removing (via renaming) various directories, I eventually found that my issue resolves when I rename config/input/F-5E-3. I eventually narrowed it down further to a specific input device. Renaming that one .diff.lua file fixed it. So what about that file caused the problem? I went into my input settings after naming it back to see what was bound to it. Just a couple latching ON/ON switches, one for nose strut, and one for NWS. I look down... and sure enough, the NWS switch is on. Flip it back off, and ground crew can hear me again! This must be related to the usage of the NWS button as radio while airborne (coincidentally(?) it's currently bugged per another report). It appears that you can't talk to the ground crew while the NWS is engaged (at least with the engine off). So while I've found the source of my particular issue, this does seem to be a (very) minor bug.

I tried a few more things, but no luck so far. @BIGNEWY I ran your track. When I watch it, the comms come up fine, like they should. If I take over at any point though (even after the successful connection of the air supply) they no longer work. I ran through the rest of my modules (I can list if you need me to), this is the only one having this problem. I've also tried on other terrains, same thing. All signs point to it being corruption in the module - but I would think completely deleting and redownloading it should've worked. Are there any other files that might affect this?

I tried the slow repair before I posted, in addition to deleting and reinstalling the module. DCS is standalone open beta. I'll try the track tonight.

Yeah, this is the built-in instant action Caucasus cold start mission (went with that to rule out user error), but it's the same in any mission I've tried. The mission (and presumably any others) work fine on my laptop, I can only imagine something got corrupted in the files somewhere on my desktop (where this was recorded), wherever the comms functions are defined. Just don't know where to look, since I already deleted and repaired dcs.openbeta/mods/aircraft/F-5E. I think it has to be the module though, not something else, because I tried it with the Hornet and it worked fine. I don't think it's a mission issue either, since it happens on any I've tried, including a new one in the editor. Even if it was a coalition issue, I still think I'd get the "Connect ground air supply" voiceover, just not the "Copy". If you have any troubleshooting suggestions though, please let me know.

Yesterday I had a game crash while flying the F-5E online, and when I restarted, the comms menu wasn't working anymore. When I select something from the menu (e.g. "Connect ground air supply") my pilot doesn't say anything, there's no response, and the thing I asked for doesn't happen. Doesn't work either for ground crew (canopy open) or for ATC (Radio on and properly tuned). I've tried other modules and they still work normally. I've tried restarting the game, restarting the PC, running the repair (both fast and slow), and deleting the module files, then repairing. Does anyone have any other suggestions for fixing this? Track attached. F-5 comms issues.trk

Thanks for the suggestion. I messed around with that a bit last night before I posted, but I couldn't get it to affect the controllers. I figured, based on the name, that it was more for setting up emulation of controllers with hand tracking. I'll try some more tonight, maybe there was something I missed.