Hummingbird

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.

I'm Danish so can understand what is said. What narrator is saying is that as the video shows the F-16 still can have a good chance against the EF in a dogfight, esp. at low speeds. But like Spectre kind of alluded to, it's not evidence of anything. Infact all it is is a Danish F-16 pilot narrating two pieces of HUD footage to a civilian audience (explaining what the different symbols in the HUD mean along the way), and probably with the main intent of showing that the RDAF's F-16 is still (early 2000's video) a potent fighter that isn't helpless in a DF against the newer ones out there. Update: Also just to be clear, the narrator at no point says the F-16 has better maneuverability than the EF at low speeds, just that it [F-16] has a good chance, esp. at low speeds. Once again though, early 2000's video, for a civilian audience.

It's interesting to see how quick & smooth the slats are to extend and retract in that video, it's a very cool system. Also I wonder, were the leading edge slats on the F-4 variable in their degree of deployment, i.e. would they be half extended at a certain AoA and gradually come out more as AoA increased? or was it either fully in or fully out ? Asking as on for most fighter (for example F-16, Mirage F1 or F-5 Tiger) the degree of leading edge device (flap or slat) deployment depends on the AoA.

I guess the opinions on the slats differ, as so far I've read lots of positives about them from other F-4 pilots. But they were also all airforce, not Navy. Btw, a cool little video showing them in operation on greek F4E:

Did the slatted F-4 engage in any combat in VN ?

I guess it's akin to when the maneuver slats/flaps deploy in the F-14, here you also only notice it when flying slow and level.

I don't know, I just noticed he said "if you're not watching for it, then you wont know they've moved ". But that could be refering to when maneuvering. In the landing pattern, or when flying level at low speed, I can see that it might be noticeable as Kirk says, as here even slight changes to pitch moment & trim are usually noticable.

Interesting, the opposite is mentioned in the instruction video: Or perhaps you're refering to only when in the landing pattern at low speed with flaps & gear down?

Oh didn't know he flew the Phantom, and I didn't want to come across as lecturing, just merely stating the conclusions of the report. There's no doubt the F-4E, esp. the slatted one, was draggier, and lost some speed, that's also outlined in the report. But apart from when landing the report indicates the slatted F4 was just as nice to fly, and more so during maneuvering. In cruise flight it was described as the same as the unslatted Phantoms. In short we should expect a really nice flying aircraft

Hmm... as far as I can read, apart from when landing, then the F-4E is said to be the nicer aircraft to fly -> esp. in maneuvering flight. As I gather it, the reason the slatted E was less comfortable to fly on landing was first of all the increased AoA limiting the forward visibility, and secondly that with gear & flaps down at low speeds a decrease in longditudinal stability and thus increased sensitivity in pitch in a landing approach at 19 units AoA was experienced . Test report: https://apps.dtic.mil/sti/pdfs/AD0904287.pdf Some key take aways: - "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-eguipped aircraft should be- revised to indicate the sustained load factor capabilities demonstrated during this test program." - The aircraft pitch response and pitch rate capability at high CN'S were satisfactory, and the increased stick force and deflection needed to attain CN'S greater than 0.9 provided additional security against inadvertently exceeding safe AOA limits. - Simulated air-to-air tracking tests showed that terminal tracking could be effectively accomplished up to 30 units AOA without excessive pilot workload. - Static and dynamic longditudinal stability in the cruise and combat configurations was comparable to that of the unslatted F-4E. However, in the power approach configuration with no external stores and a mid eg position reduced static stability was noted in the 17 to 21 units AOA range. This reduction of reduced stability made precise control of AOA moderately difficult during landing approaches at 19 units AOA - The aerodynamic stall warning characteristics of the test aircraft were generally better than these of the previously evaluated slat configurations, as well as those of the unslatted aircraft. Conclusions: "The two-position slat test results show an increase in turning capability in the subsonic portion of the flight envelope compared with that of the basic F-4E, and were comparable to those obtained with the previous fixed slat configuration, Agile Eagle IV. Flying qualities of the slatted F-4E were basically comparable to those of the unslatted aircraft. Most noticeable in the flying qualities area was the increased maneuvering capability at high angles of attack."