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? The F-16 has a probe type AoA and no AoA vane that moves. An AoA vane moves freely with very little friction, but if would have no friction it would be hanging straight down. It would make no sense if the AoA would indicate a 90deg AoA on ground. Just tested. steady 20kt wind, no turbulence, static airplane and the AoA gauge fluctuates between 0 and 20 units...that's definitely not realistic.

No. The 1.6G occur between 20-30deg pitch. With increasing pitch attitude the G-load decreases, to less than 1 as she reaches the top of the (unintenional) loop. Interestingly with decreasing G-load the FCS increases the stab deflection to around +18deg at 80kts.

Once you have established the +20deg pitch attitude the plane will initially continue to pitch up with approx 1.6-1.7G. If you take off with auto flaps and +12deg stab trim, the stabilators will very quickly reset to the same +5deg after reaching the+ 20deg pitch attitude, like in the 0deg trim case and the result will be the same 1.6-1.7G pitch up. You can trim to 0deg, but this will take around 1min!

Noticed during testing the infamous pitch up with auto flaps, that the trim rate with the flaps in AUTO is only 0.1deg/sec if you select them while still on ground. This somewhat explains the complaint that trim doesn't have any effect if you take off with the flaps in AUTO, but it's actually the FCS that doesn't let you trim with more than 0.1°/sec which means that it's effectivelly ineffective. Tests: Start mission on the runway (half flaps) and trim from +12deg to 0deg = 6sec Start mission on the runway (half flaps), set flaps to auto and trim from +12deg to 0deg = 120sec Yes I know, you are not supposed to take off with the flaps in AUTO, but this is a) a simulator, and where else if not in a simulator you would/should train non-standard procedures/emergencies etc. b) this might affect other FCS areas as well.

Did a few tests (clean, 50% fuel) and while there is a very noticable pitch up, it's easy to counteract/control. Since you are not a passenger and hence you should always actively control your aircraft, this would not be a real problem. The main problem comes from an apparently wrong trim simulation if you take off with the flaps in auto! Resetting the trim before take off is somewhat sursprising. 1. flaps half > decrease trim from +12° to 0° = 6sec 2. flaps auto > decrease trim from +12° to 0° = 120sec, that's 0.1°/sec! 3. Half flaps (+12°), mil thrust, full aft stick at 110 (to confirm 24° stab deflection), neutral stick at 20° pitch attitude and the stab deflection will be around +3° The pitch attitude will continue to increase, the climb speed will initially increase to ~190kts but will decrease to 110kts with the highest pitch attitude being a tad over 50°. So you have the dreaded 'pitch up' with half flaps as well. 4. auto flaps (+12°), mil thrust, full aft stick at 110 (to confirm 24° stab deflection), neutral stick at 20° pitch attitude and the stab deflection will be around 9° with a much higher pitch up which will quite a bit of forward stick to counteract. 4a. with auto flaps and the trim reset to 0°, the stabs will 'reset' to ~5° after take off rotation with a less aggressive pitch up. The main problem is that the stab trim still runs at 0.1°/sec which means it's completely ineffective since the FCS is much faster, hence the impression that trim doesn't have any effect. But the trim is actually not moving at all.

Confirmed, the AoA vane doesn't move. But it's so tiny that it's interesting that someone did notice this animation glitch. That said, how should it be moved by the wind ? Usually they are parallel to the ground if the airplane isn't moving at an exceptionally high speed on ground.

It might be a bit more difficult, but not significant IMO. Depending on the technique, the nosewheel drops just below 100kts onto the runway. This seems to be roughly in line with the -1 which mentions that full aft stick at 100kts is possible without lifting the nosewheel from the runway.

+1 I didn't see any 'waving'. Just a gust/turbulence correction at 0:22. No significant stick movement at any other point. Curves are only unrealistic if the joystick has exactly the same lenght and travel like the real one. edit: just tested and I don't find the Su-25 to be too responsive, even without any external loads I can do the same full deflections like the Captain in this Tu-154 without any noticable bank ;)

Considerable work, since the whole high AoA and stall characteristics would need to be redesigned. Furthermore the approach speed with the slatted wing is 10kts lower. @meti140; what's a 'runaway stall'? Never heard or read about such a stall.

Great it works now :) enjoy :) :)

Just tried taxiing (SP) the Su-25 and the Su-25T (100% fuel. no external load) on the runways in Senaki and Mozdok. On both runways the shock struts nicely filter the uneven runways and you have the expected slow frequency rocking motion. But in both cases you additionally get the very high frequency, 'tire failure like', minimal but nevertheless annoying camera shake.

A lightly loaded F-16 could easily takeoff from a carrier, even at 0 wind since the t/o distance at low weight is only 800ft. With a 20kts headwind this distance decreases to 500ft.

So much nonsense, sigh. Looks like you don't know much about airplane design and certification. A 'whole new manual' has absolutely nothing to do with a 'significant performance difference'. If you are using different engines, if they have a very similar, or even identical performance, you need to re-fly and re-test and publish all performance data valid for this airframe/engine combination. Btw. you don't need a 'whole new manual'. In case of e.g. the F-16 there are simply separate performance sections for the GE and the PW engines, and guess what, the difference in landing distance difference is (of course) negligible. You definitely don't need scientific proof to find out that there's a quite a difference between rolling and sliding friction and that idle thrust of the small F/A-18 engines doesn't have a significant impact on landing distance.

If you honestly believe that there's zero difference in braking capability between anti-skid braking and locked/sliding wheels, then any further discussion is useless. Not 100% correct? We are talking about a 50% error! Please enlighten me, how to actually read/interpret the performance tables since you claim that 'they aren’t used that way IRL'

You have apparently never tried to operate any controls in a RW cockpit in turbulence ;) Auto throttle systems are usually doing a rather bad job in turbulence and in most planes it's SOP to disengage the system in severe turbulence. Again, the ATC is a convenience item, nothing more. If it doesn't perform the way it should, or if it disturbs your operation, disengage it.

I've explained already why it is this way, that ATC behaves that way IRL, it's definitely not a design flaw and there's nothing to improve! If you don't like throttle movements simply don't use ATC, same IRL. Can't imagine that anyone would use ATC during anything but straight and level cruise and approach. The F/A-18 is a combat aircraft and the ATC is just convenient for a few cases, but that's it. As David said, if you are cruising straight and level, the throttles will certainly not move all the time. Apart from that; how are you performing your fine inputs in case of turbulence, even without ATC?

I highly appreciate your tests :), but it would be great if you could aim for standard no-flare landings (like the above one), which will result in the most precise measurement. Brake application was almost immediate in the above video btw :)

How did you get 4000ft? Using the landing distance table I get 2600ft (without flare)? edit: just watched the video, I didn't notice any flare and you didn't cross the threshold at 50ft either.

Apparently you do have a problem ;) The runway at Batumi is 8000ft and the landing distance for a flared landing at 30000lbs IRL is 3800ft. This means that you should be able to come to a full stop halfway down the runway if the brakes would work as they should!

And how much distance do you need with this method?

I don't understand this question. Again, if you have to operate the TDC it doesn't make any difference if you move the throttles manually or the ATC moves them. Furthermore the throttles shouldn't significantly move when e.g. in a steady state cruise. During the approach things are different, but you shouldn't do anything else than flying the F/A-18 ;) One advantage of the moving throttles during auto throttle operation is, that you have the immediate feedback about power changes and the present power setting without having to constantly scan the engine gauges.

Especially if the autothrottle is controlling the throttles on 'civilian' airplanes it's required that you keep the hands on throttles at all times during the approach. The go-around button and A/T disengage button are located on the throttles! I would expect that you need to apply considerable force to disengage the ATC in the F/A-18. On e.g. the 767 you can't disengage the auto throttle by manually moving the throttles since the auto throttle system immediately repositions the throttles as soon as you let go of the throttles. But you need to apply considerable force to override the electric motors. edit: force required to disengage ATC on the F/A-18 is approx 12lbs.

It's the same like the auto throttle in e.g. a 737, 767, etc. which means an electric motor is moving the throttles. You can't 'break' it. If you apply force to the throttles, or you hold them, the ATC will disengage. Since you always have the hand on the throttles, there's no problem to operate the switches the same way as usual when manually controlling the throttles.

We can agree, but not ED, since they consider this obvious bug as 'correct as is'....

CB = circuit breaker G = gravitational force. 1G = level flight. If you are pulling back on the stick you are increasing the G load (Gs) which 'pulls' the gear down and makes retraction more difficult or even prevents it.