Tiger-II

I've been doing some reading about the MiG-19 and even have some books on order. So far I've discovered the MiG-19 was the best day fighter of its kind when it was built, and has a very impressive performance envelope to include maneuvering up to +8 g without losing airspeed in a turning fight [source: flight test report from an Aviation Week and Space Technology journal article re-published in a book called Military Aircraft Pilot Reports (McGraw-Hill, 1996)]. Yet to test this in the sim, but that is a whole heap of advantage right there.

Interesting discussion. AF447 - the official report is a whitewash to bury the fact the F/O royally screwed up and to hide deficient training and systems for post-stall recovery. It was a crash that should have never happened. Aircraft stall characteristics can be anything from not-a-damn-thing, to shaking so violently you can't see what you're doing anymore. I don't actually know what would be correct for the MiG-19. From what I do remember reading, it gives a little bit of warning before the departure, and we have that in the sim. We also get a little bit of Mach buffet around Mach 1.0. Nice touch, and I don't remember that being present the last time I flew it.

Learn to aileron roll (aka, pull in the same plane-of-motion as the bandit). Modern fighters won't let you use the rudders, either (well... depends, but it isn't really the correct technique).

I'm going to! Just wanted to hear what more regular pilots of it had to say.

I think people forget that older aircraft had it designed as part of the "DNA" to be relatively stable in the absence of pitch stability or FBW. The reason modern jets are crammed with stability augmentation is because the aircraft are designed to be unstable by default, to such an extent a human could not actually fly them. Ergo, they are designed to be flown using FBW control systems, and as part of that, require stability augmentation as they want to depart controlled flight. Older aircraft needed to be able to be flown by humans, so their stability is actually greater than that of modern aircraft. Where older aircraft have a problem is they can be departed from controlled flight more easily, but this does not mean they are not stable inside the normal flight envelope.

10 months later... Any news? Would be awesome!

Hi, This module is a long-time lurker on my wishlist. When I last flew it (maybe 3 years ago?) there were some issues with the flight model, including such things as ability to climb to 80000 ft under the right circumstances. I know there has been much work done in the intervening period, and I'm wondering if it is now in a better state and worthy of a buy? I had a lot of fun flying it last time, and I'm hoping the changes have been for the better. I'd really like to add this module to my hangar. Thanks in advance!

It's weird but you'll get the hang of it. Basically, just pull the power off for a second or two, then push it back up to cancel AB. Quite easy.

I flew it the other day for what must be the first time in over 2 years, and it broadly felt good to fly. My biggest criticism is the engine just quits if you lfy too fast. The real thing doesn't do this, and if anything you'd get surging/banging sounds out of the engine before it died. Seems "off" and a hack to offset game-isms. I rarely use nav functions in DCS in anything. Most of the aircraft I fly don't even have moving maps, anyway. It's definitely an older model, and anyone who was around when it was first started will be aware of what happend. We are still unable to get away from 3PD that don't understand systems and are unable to write them properly. Not so long ago a more recent module was feature-frozen with wholly fictional behavior (presumably because the math was beyond the developer). It's not hard if you actually understand what you're doing, and the level we are trying to get to with DCS means you can't be half-assed about it.

The F-100 did it a lot as a result of its wing sweep and tiny vertical stab. It was pretty much eliminated in later versions of the [real] aircraft after they re-designed the tail. They also mandated higher approach speeds which helped get it out of the danger zone.

That pretty much sums up my understanding of the modelling, too. It's over-simplified. The RADAR literally looking below the local horizon is insufficient. The question is does the target have a background, what angle is the background at (flat ground vs. mountain), how far behind the target is it, and how far from the emitting RADAR is it?

"It depends".

Sounds legit. Something is still happening when paused.

LD-10 is a pretty easy weapon to use once you understand the modes. Lofting it, even if it doesn't appear to be beneficial (same for SD-10) helps the missile avoid that initial turn under its own power. It is converting all its energy to turn rate rather than accelerating, so aiding it allows the missile to use a few seconds extra burn to gain speed instead (and speed = range). I always loft them.

I think some people need to hit the books again and refresh themselves on the various flight controls and their effects. Right roll = left aileron down, right spoiler up. Aileron down = increased lift, increased drag. We are turning right, so yaw here is adverse. Spoiler up = increased drag, loss of lift. Drag may be more or less than the opposite control due to various factors (speed, area, deflection, location). Yaw effect may be variable based on location (inboard will have least yaw effect even if very high drag). Just because you lose lift doesn't mean the spoiler is neutral for drag. It is still stuck out in the airflow and has an associated turning moment. The only question is whether the forces ultimately balance out to be noticable or not.

It has been said before and I'll say it again... there is something alluring about the EN1 voice when she says "Missile! Missile!". Being shot at will never be the same...

I thought we were discussing it from the pilot perspective rather than an engineering perspective, but you are correct. The end result for a pilot, is that an unstable aircraft is always trying to end up out of control, and we do not experience this in the sim because the models are stable. It's not hard so much as the fact the average desktop computer lacks the processing power required to do so in real time, which we require for any usable flight simulation. Super-computers can about manage it, but anything of any real use is not capable of being computed in real-time. It's easy to defeat AoA protections of even something like an F-16 - point the nose at ~45 degrees nose-high, wings-level attitude at idle power. By the time the aircraft bleeds off speed, even if the aircraft starts to pitch nose down, gravity will take over and AoA will far exceed 60 degrees AoA. It should settle quite nicely into a pretty interesting situation. The F-16 as modelled right now doesn't seem to do this. It just kind of falls out of low speed flight and re-gains speed without any problem (i.e., as if it never stalled). PS: 60 degrees AoA isn't a random figure... My point still stands that the flight models are stable. It's easy to model instability in the aerodynamic sense - you add something that approximates neutral or negative stability, then create a second layer on top (e.g. FBW sim) that corrects it. The point is though, without doing that, and in the absence of real-time calculations for airflow (turbulent or otherwise) the models themselves will not inherently create this behavior. Inadvertent spin is another side-effect of stability of flight modelling. A spin is due to increasing yaw rate, created by stalling a wing (e.g. slow flight in an un-coordinated turn). One wing will have a higher AoA than the other, causing it to stall. Beyond the stall AoA it creates an increased amount of drag. This drag causes the yaw moment to increase, increasing yaw rate to that side. As the other wing accelerates it generates more lift, and causes the aircraft to roll over (until it, too, stalls - this is why aircraft sometimes enter inverted spins from an upright entry). The yaw rate becomes such that instead of the aircraft continuing to turn, conservation of momentum means that the aircraft stops turning/flying and starts rotating around the yaw axis (linear momentum becomes angular momentum). At this point it has departed controlled flight and unless the pilot does something, will continue into a fully developed spin where the aircraft is no longer flying, but rotating as it falls like a sycamore leaf to the ground. We do not see this in simulators why? Because the flight models don't or can't compute it. The only way we can get them to spin (usually) is by inputting certain inputs, and only if certain pre-determined conditions are met, will the flight model act like it is spinning. The equations used for normal forward flight are not capable of developing to a spin without additional help. This seems to be the point that is being missed when the word "stable" is used. It applies not only to situations like the above, but stability in the aerodynamic sense. Some aircraft have interesting roll stability characteristics. The 747, at roll angles less than 32 degrees, demonstrates positive spiral stability (that means the pilot must hold in some aileron to maintain a constant bank angle). At 32 degrees of roll it will hold the roll angle with neutral aileron input. Beyond 32 degrees of roll, it has negative stability, and will roll tighter into the turn unless you hold some opposite aileron input to prevent the roll angle increasing further. A simple model of dihedral will not model this particular behavior. It will always be positively stable at all roll angles. It must be augmented by additional calculations to determine the strength and limits of positive, neutral, and negative stability. Just look at what happens when you get the F-5 into a high AoA situation and add rudder. It yaws, but the reality is the aircraft should roll! Even this is not correct. This is because the calculations being made even in this "simple" situation of high AoA are not adequate. If the flight models were more sophisticated and modelled the more noticeable effects accurately, we wouldn't even be having this discussion. 7.22 makes for interesting reading for those who are still unconvinced that flight modelling is quite inaccurate. The flight models are failing at smaller (yet significant) details, so why is everyone so convinced they're right on the more important details? Just because something "hits the numbers" doesn't mean a whole lot for how the calculations were made to get there. https://www.f4phantom.com/docs/F4_Phantom_Guide.pdf

LOL. Do they? Really?? Do you even know what instability actually is? Two aircraft you really should be discussing didn't even get a mention, which is very telling indeed. I have nearly every DCS module going, and I can tell you that at the edges of the flight envelope, several of them are quite seriously deficient. They don't perform as the real aircraft would (because the flight models are inherently stable). MiG-15: if flying at high altitude/high Mach and you get into an accelerated stall, it should get into an aggressive, unrecoverable spin. F-5: If you do a loop at too low an airspeed, the aircraft should want to pitch NOSE DOWN and enter an inverted spin. It does not. High alpha flight is also too stable, and in fact doesn't remotely reflect the difficulty of its handling. You can roll with ailerons without any care. The real thing would kill you. F-86 is hard to spin, but the real thing wasn't. MiG-19 last time I flew it (2020?) had some strange behaviors and didn't behave as reality. It could also climb far above its service ceiling. F-14: it used to spin well (initial release) but because of "balance" or whatever the justification was, they dumbed down the flight model so now you need to work to spin it (not realistic at all). It was far better at release. The real thing was very prone to spins if mis-handled, especially at low speed. The two aircraft you didn't mention which should be top of the list, are the F-18 and F-16. These aircraft were designed to be unstable and can't fly without FBW. Did you explore the flight envelopes of either of these? Again: too stable. Don't get me started on the F-16 handling in pitch. It improved recently, but still has a long way to go. The F-16 also doesn't seem to understand what a stall is. It just mushes. All these problems are the result of the inherent stability of flight models. Instability must be added. Equations are insufficient to capture the instability of their designs as the airflow itself can't be modelled to sufficient detail to do so. It's a combination of aerodynamics and turbulent airflow around them that causes these handling difficulties. Add on top of that the fact that some aspects of the flight models are seriously lacking in fidelity (the LEF of the F-5 for example). Aside from adding a bit of drag and lift, they don't seem to affect the handling of the aircraft at all. The magic words that hardly any simmer ever has to utter is: "I did a dumb thing and the aircraft departed controlled flight". Inadvertent spins are non-existent in any sim I can name, yet they kill many aviators in real life on an annual basis. The reason is: stability.

Take an empty jet and 50% fuel load, and as you approach 180 kts, pull the power off so it slowly accelerates through 180 kts, then you'll see it in operation. The tires only burst if you abuse the aircraft or exceed absolute tires speed limits (200 kts IIRC). Tires really do have such low safety margins. I wish the pitch problem would be addressed as a matter of priority. It flew really well and now is busted.

Sims are too stable (flight models do not suffer the instability of real aircraft or model the minor perturbations you get from flying through real air), so I'd say it is a non-issue if you are relatively smooth to begin with (a major problem sim pilots suffer is they are not smooth). If you can refuel the F-18, you should be able to refuel the F-4 (in the sim).

Yes... not much written about its deployment or successes.

Ahh! That's the part I missed! Thanks for the procedures. Very useful!

Regardless of where the trim is, the shift of the center of pressure will require you ease back-stick pressure through lift-off. I'm just pointing out that speed vs. trim isn't the only thing affecting the change of trim condition.

How do you place objects to pick up? Add static items?

Swept wing causes a pitch up at the stall, but during takeoff you are above the stall and accelerating. As the aircraft leaves ground effect, the center of pressure moves forward, causing a pitch-up moment. This, and the fact you're accelerating above trim speed, require that you trim nose down after lift-off.