Hummingbird

Just to be clear what to pay attention to in the video, it's when going straight and level, where I'm barely or not at all touching the pedals. I just can't seem to properly stabilize the chopper, it keeps wanting to subtly bob from side to side.

Yeah, bug reported this about 3 years ago when I noticed some pretty extreme climb performance: Viggen is basically a rocket until its engine dies around ~15+ km height, not really losing any speed until then. Had the engine not died, it seems it would've happily gone well into the stratosphere Meanwhile the F-15 is, as it should, losing speed gradually with altitude.

When trying to stabilize the chopper in a desired direction after a turn for example. I find the Apache very unstable in roll when just going straight, where it just always wants to subtly swing left & right like a pendulum in roll axis. By comparison the Hind is rock solid, and feels like a precision instrument.

Ok, here's a video of me doing a few circles round Mozdok AF: Now it may not look like much as I'm doing my best to keep the chopper stable, but as you'll notice it subtly but constantly wants to swing a little from left to right (like a pendulum), even when I'm not touching the pedals at all, and only using the cyclic. Having to constantly adjust in the roll axis as the chopper does this is very tiring, esp. as I just can't seem to get it perfectly stable after a turn, or just in general going straight, nomatter how hard I try. The Apache always seems to want to roll abit from side to side for me. By comparison the Hind is just easy, and gets stable real fast. I also feel like the Hind stabilizes much better in heading after a turn, i.e. it seems to stabilize more in the direction I want to go than the Apache, which after centering the pedals always seems to wanna slide more in an unwanted direction. In general the stability system in the Hind just feels way better, which is a surprise to me considering how supposedly advanced the Apache is supposed to be. Now I don't know if the SCAS is finished yet, so this could very well all be ironed out in later patches, but it's just how it feels to me now. PS: I had wind set to zero on the mission, so that isn't a factor.

But why is it not an issue in the Hind then? Also I feel like I'm centering it quite quick, but also I believe I am using the setting where no inputs are registered post trim until I center the stick, so should that even be an issue?

I'll record some footage later today and post it here. It's a super annoying issue for me when flying the Apache.

I am, so that sounds good Hopefully that solves the issue, as I can't really fly her atm due to that odd instability in roll.

Yeah this is exactly what I'm feeling too, that rocking pendular motion in roll as you try to level out. Feels very strange that the Apache should be doing that considering the advanced SCAS it's supposed to have. If realistic, it's certainly not a very impressive system compared to what's in the Hind, which is way more stable.

Has anything been changed/updated in the SCAS roll channel in the past few months? Just asking as like I said earlier, I really don't remember the Apache being so unstable in the roll axis during my first month of flying her. So when I came back to her a few weeks ago, I was surprised at how much she would rock in roll after no longer commanding any and just going straight. By comparison the Mi24 feels rock solid in roll, and quickly stabilizes after any roll commands. Is the RL Apache SCAS really that much worse than the Mi24's ?

They're certainly visible on real life guncam footage, so I'd say it would be really cool and add abit extra immersion if they made em so in DCS as well.

So here's a request I know isn't exactly realistic considering the real chopper doesn't feature a trim hat for trimming in small steps. However a trim hat functionality to make small trim corrections would be really helpful for those of us with regular spring centering jeysticks out there, as the 'hold and click' button trim technique is quite fatigueing and not very accurate for us as compared to if we were using a full length non centering stick/cyclic.

Hmm, I think that oversimplifies it a bit. Tuning the FM so that everything matches the real life performance charts, i.e. ITR, STR, straight line acceleration, climb rate & top speed (and for all altitudes), is obviously a complex & difficult task, otherwise it wouldn't give the various devs so much trouble. Take just HB's two other modules, the F-14 & AJS37, they still have performance discrepancy issues after several years. Now finding these, if there are any, with the EF module is obviously going to be almost impossible (unless it's just completely unrealistic ofcourse and either flies like a B17 or shoots to the moon like Saturn V), since we have no official performance charts to cross reference. Hence the slight worry. But I do have confidence in the devs, esp. since there are several RL EF pilots onboard, instructors no less, so I believe the FM will be close. Ultimately though, time will tell.

Couple of questions regarding the combat flaps switch: 1) Is it off as standard ? (RedKite's video seems to indicate so) 2) If answer to question #1 is yes, why is that? Reason for asking being that if the flaps/slats automatically deploy/retract within their speed/AoA limits anyway, then why turn it off? 3) Is it because this feature is only really meant to be used at rather low speeds for min radius, but not max STR? (I ask this as I noticed the LE slats are still automatically deploying when the cmbt flaps switch is off, just not the TE flaps, which indicates the switch is primarily for max lift but lower L/D) In short I'm trying to understand the logic behind the system, so as to prepare myself for how to properly use it.

Kermit I am very interested in seeing some papers to explain these "unexpected phenomena" you're talking about, because the well known coanda effect isn't one of them. As for the Cl/Cd graph I just showed you, it's from flight testing, and there are load factor charts there to compliment them: (full line is with slats, dashed line is without ) To get back to what started this whole debate, your claim that these devices shouldn't improve STR is false, pure and simple (as can be seen pretty clearly from the charts above). That's what Sgt. Pappy is trying to get you to understand, whilst you seem to want to avoid it at this point. And the positive effect on STR (& ITR) isn't unique to the F-4, you see it on the performance graphs of all such equipped fighters (Sgt Pappy already refered you to the F-14 as another clear example), all the way back to WW2 where some of the first to enjoy these benefits were the Messerschmitt 109 and 262, which is what prompted North American to copy the design for their F-86. In short there's a good reason these devices and/or derivatives there'of have been used on a lot of fighter designs since then.

Yes, same problem here. She seems very wobbly in roll.

Do you have a source for this so called "unexpected phenomena" without a name on the Phantom? So far I don't see it playing out on the actual Cl/Cd graphs for the F-4E in the report, instead they work exactly as I've described, I wonder why Also btw, automatic slats work in a range of AoA, not "a" single specific one. Also in general they're not speed dependant, and work entirely as a function of AoA, unless they're power assisted. You misinterpreted what was written. I'll try again; Typically slats increase the critical AoA on a regular straight wing from a normal ~15 deg, to about ~25 deg.

Sorry but it's very evident based on your drawings that you've completely misunderstood how slats work. Slats dont work by creating a vortice over the top of the wing, quite the contrary. Slats work by delaying boundary layer seperation, i.e. they help maintain smooth airflow over the top of the airfoil along a much higher AoA range -> higher critical AoA (usually from ~15 to ~25 deg on a normal straight wing), Clmax and L/D at typical AoA during thrust limited sustainable turns. https://images.app.goo.gl/ctFKB6VxYShw7uELA https://images.app.goo.gl/HtTziaqKQMFfCoV49

No, read the F-4E slat testing program report. The thrust-limited sustainable load factor goes up in the subsonic speed range thanks to the addition of the slats.

Sgt. Pappy is correct. If the slats are engineered to only start opening at a certain AoA, then they will improve both the ITR & STR of the aircraft, you can observe this effect on the performance charts of basically all fighter aircraft so equipped. To quote one of the conclusions from the F-4E slat testing program: - "Thrust-limited turning performance data obtained during the test program indicate a significant increase above the performance demonstrated during F-4E Category II testing (reference 6). The F-4E Flight Manual for slat-equipped aircraft should be revised to indicate the sustained load factor capabilities demonstrated during this test program." Why is this? A plain wing usually starts to experience a noticable increase in turbulent flow over the top surface starting around 10.5-11.5 deg AoA, hence most automatic LE slat/flap devices are designed to begin deploying in this AoA range. The effect is a smoothening of airflow over the top of the section and significantly increased critical AoA, resulting in a decrease in drag and thus increase in the L/D ratio (cl/cd). Simple illustration to showcase the effect: https://imgur.com/uR1whTF Now that being said, the L/D at clmax often decreases (i.e. L/D slope becomes less steep), but you don't fly at Clmax in a max sustainable turn anyway. Also if you're pulling Clmax you usually also desire a quicker loss in speed at the same time in order to reduce your radius as fast as possible. Hence why almost all modern fighter jets feature automatic LE slats/flaps.

I hope you're right. They got PhD's working on it in conjunction with EF instructor pilots, so I'm sure it will be believable. It's just hard to beat a module that matches the charts, as it gives a special feeling of authenticity That said, who knows, maybe TG have the charts and will use them for the module, just not share them publically as pr. agreement with Eurofighter GmbH.

I can confirm I have the fuel feed issue as well every time. Also the right engine refusing to start bug is back in all its glory.

this bug is back

No, that's the thing...

Only thing I'm slightly worried about is the lack of official EM charts based on RL flight testing to consult. Without this the realism of the FM is going to rely entirely how close CFD testing and physics calcs can get the module to reality.