I just saw this post, and I’d like to make a small correction.
Contrary to RL, the neutral point of the joystick and hence the elevator doesn’t change when trimming.
This means that e.g. pitch authority is too high in the low speed case if the aircraft has been trimmed for this speed.
In aeroplanes with a trimmable horizontal stabiliser (THS), the elevator travel relative to the stabiliser is not affected by the trim setting. The A320, 747 and 787 all have a THS. In the 152, though, you are entirely correct, as it works with tabs that aerodynamically move the elevator to the trim point and the stabiliser does not move.
If you would have read my whole post and quoted it correctly, no ‘small correction’ would have been required, because I’ve stated that my explanation only applies to elevator trimming.
Btw, a THS can be found in many small GA as well, like the Piper Cub/Super Cub and the Mooney.
Particularly for airliners, the exaggerated ground effect together with way too sensitive controls makes it impossible to produce consistently stable landings. I am wondering how landing challenge scores > 1.8 Mio are achieved
I know that the sensitivity can be reduced, and I have done that drastically, but that does not change the way simulated forces on the control surfaces are interpreted. I got used to the need to push the stick during flare, however it is then unrealistically easy to induce nose up/down oscillations especially in low speed configurations. In my opinion this needs to be fixed. Small aircraft seem to behave better, but still too sensitive. The same effect is noticed when taking off, after leaving the ground effect the nose has a clear tendency to drop. Don’t know if this is the case in real life as well.
Seb was asked this question around ground-effect in a Twitch Q&A (I think the one before last), from what I recall it is still based from FSX and that it will be updated at some point (SU6 or 7?)
I did. I have heard “elevator” and “pitch” trim used interchangeably by pilots (language barrier maybe? English is not my mother tongue). Correction may not have been the correct word, clarification would have been better. If Asobo read this, they need to be aware of the difference.
The pipers you mentioned do not have a THS. They have a stabilator. While a THS only trims the aircraft, the stabilator provides both primary pitch control and trim and is subject to the same travel restrictions as an elevator. The Mooney does have a THS.
This quote above is wrong. The Cubs do have a THS; it is other Pipers, such as the PA28 different models, that have the stabilator. Disregard. I have not found a “crossed out” format.
Regarding ground effect, I saw a post with a good explanation of the whole aerodynamics and weight/balance being fully wrong (pressue centre in front of CG and the horizontal tail lifting upwards), and that spells disaster at landing, to the point that the column must be pushed during the flare due to the ground effect in the stabiliser providing nose-up pitch moment (which is wrong if simulated that way). I’ll locate the post and link it here. I’ll try to modify the empty CG of the aeroplane this afternoon and post results. I’ll try with the 747.
I think it was @Boufogre who cracked the case. As soon as you take a straight wing and adjust the sweep angle, things get weird. I don’t believe this got fixed yet…
I am indeed wrong. It is other Pipers that have a stabilator. I lost myself in research and inadvertently got to another aeroplane’s info. I just found a POH and the Cub definitely has a THS. I’ll cross out the wrong info on my previous post.
I’ve tried to upload the video to no avail. The result is, even with a crazy forward CG, as seen in the picture, where I had the aeroplane trimmed for the approach and neutral elevator:
I hope also they fix the ground effect because it is sometimes really frustrating to land with these airliners because of these to strong ground effect
I came to this thread after struggling with 747 landing challenge at JFK. Overly strong ground effect makes smooth landing to certain spot on the runway very difficult.
What I observed was that the ground effect issue is only related to runway. When you fly very low over the ground or runway threshold there is no issue. Once you cross over the actual runway the plane will float excessively. I noticed the same issue with other planes too, but larger ones seem to suffer the most.
I was landing the A320 - which I flew in the sim at Jet Blue University. Every one I have tried was still floating at 120 knots or less. I can tell you from first hand experience that will not happen in real life. Landing is MSFS is much harder than it was flying the real deal.
The sad thing is, it was much better before the July update. They seemed to have inadvertently increased ground effect 2x with the sim update in July. It’s been mentioned before but as of right now I don’t think anyone is looking into it.
I don’t understand what 120kts have to do with floating.
Without knowing the weight 120kts means exactly nothing.
You don’t know how it is IRL. You have flown a level D sim a few times, that’s a big difference.
But I still don’t know what you are trying to say and why landing the A320 in MSFS is more difficult.
Weight on the left, landing speed on the right. Unless you have no passengers/luggage and are down to minimum fuel, you will be landing at 120 knots or greater. But even without that… I would come in at 120 knots, throttle to idle at 30 ft and the speed bleeds off without any drop in altitude. That is not real life in any airplane. When you pull the throttle to idle (barring a super strong head wind), you are going to lose lift, even with ground effect due to induced drag from the flaps slowing the plane down.
I fly in real life (not an A320), not just in MSFS or in simulators.