need advanced help on trim button press and release

[-MadCat-]

I've tried everything that's been suggested in the past. Maybe the bug only manifests with certain joysticks or something.

 

I don't think the problem is all about certain joysticks or some like that.

 

As I already described -> here <-, I came to believe there is something wrong with the trimmer in the sim.

That is my opinion, based on knowledge and observation.

So everybody please don't start to hate or telling me I'm doing it all wrong and have no idea how to fly it,

which I know quite well how to.

I've PMed Evil already with my concerns, but didn't get an answer yet.

 

Greetings

MadCat

[RedRain]

This platform has many tools in the bag, use them all, but use them wisely. There is no right or wrong way, what works, works, and what doesn't, doesn't. The AP channels are great for flying a course or heading (bit like using cruise controll on your car), but you wouldn't use cruise controll for parking or tight maneuvering would you ? The AP channels are also very usefull for presidion engagement both static and mobile, as is FD mode. FD mode is great for tight manouvering, wheather it be evasion or positioning yourself between buildings, take off/landings etc. AP channels and FD mode are fundamentally the same, AP mode gives max stabilization but limited pilot authority where as FD gives less stabilization and more pilot authority. The choice is compromise and situation specific, choose wisely. Another form of trim (which Is discussed rarely and seriously neglected) is the collective brake. The collective brake should be squezed prior to making altitude adjustments via the collective, just like you would trim the pitch/roll & yaw conventially. If on board equipment is fitted, it is fitted for a purpose. I have many tools in my personal collection and avoid using screwdrivers to knock in nails, but, you can do if you want.

[RedRain]

Does turn to target function correctly when FD is engaged ?

 

I can't find out for myself right now as I'm in the middle of rebuilding my flight controls

 

Turn to target does not work in FD mode, nor does auto hover.

[Fishbreath]

The bouncing behavior is an artifact of lack of force feedback. If you don't have a stick which stays where you leave it, you can't do the frequent trimmer tapping the real pilots do. (Or at least, not easily—having to recenter the stick every time is highly inconvenient.)

 

The reason it's so hard to wrap your head around is because the trimmer button does two independent things when the autopilot is on/FD is disabled. It's both a standard trimmer and the button to command a new set attitude. The autopilot in the real helicopter has no information on controls position or controls deviation, so there's always going to be some conflict between the two. If you have a stick and pedals which don't need to be recentered, you can fly like the real pilots do. If you have a standard spring-loaded stick like most people, you can't—it's a limitation of the hardware. You can't tap the trimmer as often as you need to to fly like the real Ka-50 pilots if you have to recenter the stick every time you do.

[Irregular programming]

I don't understand why you shouldn't use the FD, as it gives you a much smoother flight! If some people are able to fly the Shark in precision with FD disengaged, fine. But I don't see how this is possible when the AP constantly tries to get back to set attitude while you try to change it... And the FD is way more elegant than just holding the trim button while you do anything apart from straight flight.

 

Because the FD does the exact opposite of what you are saying in this post.

 

FD makes the aircraft unstable and difficult to fly. Unnecessarily so, and to reiterate, I don't care if you use FD or not, I do care when people tell other players especially new ones learning the game to use it. Giving them a much more difficult time playing the game.

Edited February 11, 2014 by Irregular programming

[Extranajero]

I'm pretty new to the KA-50 and still have issues flying it, but for what it's worth my autopilot useage goes like this :-

Takeoff - 3 channels on, no waypoint selected

En route - 3 channels on, waypoint selected, route mode active

Stand off attacks - 3 channels on, no waypoint selected

Maneuver ( evading fire, rocket runs ) - FD engaged

 

I don't get too many " why the hell is it doing that ? " moments following the above routine, but the trimmer still seems to have a mind of it's own sometimes.

[Tone71]

Because the FD does the exact opposite of what you are saying in this post.

 

FD makes the aircraft unstable and difficult to fly. Unnecessarily so, and to reiterate, I don't care if you use FD or not, I do care when people tell other players especially new ones learning the game to use it. Giving them a much more difficult time playing the game.

 

That's not entirely true either...

[Fishbreath]

The real benefit to FD mode is that you can explain to someone the very basics of helicopter physics, and when they get into the Ka-50, it'll behave in a way that makes sense based on that explanation.

 

The autopilot makes flying the Ka-50 as a weapon system much easier, and the more time I spend with it, the more often I have all four channels on. FD mode is useful in a few places, like delivering rocket attacks when you don't have time to find the target with the Shkval and make a good run at it, but it takes attention off of using the avionics. I see that last point as the biggest argument in favor of autopilot almost all the time.

[Extranajero]

Anyone else find the altitude channel unreliable ? I don't trust it...

Maybe I'm doing something wrong with the collective brake key

[Flagrum]

Anyone else find the altitude channel unreliable ? I don't trust it...

Maybe I'm doing something wrong with the collective brake key

Yes, using ALT HOLD is a comfortable way for CFIT.

 

But maybe something to think about: the AP has only 20% authority. If your collective setting is now "too high" so that the AP has to apply already +9% to keep the desired altitude, there is only 1% left for it to maneuver over obstacles.

 

I haven't really tried this myself for this use case, but try to set your desired altitude at the absolute minimum of your collective setting (i.e. without alt hold your alt ist just stable - one milimeter less collective and you would start to sink) so that the AP can exert his whole 20% authority to raise the collective if necesary.

[msalama]

i.e. without alt hold your alt ist just stable

 

+1

 

Always, ALWAYS, stabilize the chopper on all axii AND the collective before releasing trim and you'll find that it's stable as a rock :thumbup:

[doveman]

Yes, using ALT HOLD is a comfortable way for CFIT.

 

But maybe something to think about: the AP has only 20% authority. If your collective setting is now "too high" so that the AP has to apply already +9% to keep the desired altitude, there is only 1% left for it to maneuver over obstacles.

 

Not sure this makes sense. If the collective is "too high" than surely the AP would have to apply -9% to maintain the desired altitude, leaving 11% for it to increase the altitude?

 

I haven't really tried this myself for this use case, but try to set your desired altitude at the absolute minimum of your collective setting (i.e. without alt hold your alt ist just stable - one milimeter less collective and you would start to sink) so that the AP can exert his whole 20% authority to raise the collective if necesary.

 

So if the collective is set 5% higher than is needed, meaning the AP has to exert -5% to maintain the desired altitude, does this mean it's left with +15% to increase altitude, or is it a -20%/+20% range?

[doveman]

+1

 

Always, ALWAYS, stabilize the chopper on all axii AND the collective before releasing trim and you'll find that it's stable as a rock :thumbup:

 

Maybe it is but those Russian pilots clearly don't have time to "stabilize the chopper on all axii and the collective" before click-releasing the Trim repeatedly and often, so if we have to in the sim it seems there must be a bug in the simulation surely?

[Flagrum]

+1

 

Always, ALWAYS, stabilize the chopper on all axii AND the collective before releasing trim and you'll find that it's stable as a rock :thumbup:

Yes! But ... that was not my point (I think :o). My point was, set your collective so that the AP has not to use it's authority to just keep the helo in level flight - it then would have too less authority left if it really has to maneuver.

 

Example: if you would need, lets say, 70% collective for level flight, but you set the collective to 50%. Then the AP would have to add already it's full 20% that it has available to keep the helo stable. If you now fly over obstacles, there would be no authority left to add more collective - and you fly into terrain.

 

CFIT can ofc also happen if all settings are perfect - just if the terrain change is too steep and even the full 20% of the AP are not enough to get over the hills/mountains...

 

Hrm, yeah, I think, your conclusion was my point. The simplest and reliablest(sp!?) way to archieve what I wrote is just to always completely stabilize the helo. Makes especially sense when one keeps in mind, that we are talking about HOLD channels - the are not magic bullets, they just (try) to do what the pilot tells them :o)

Edited February 12, 2014 by Flagrum

[Fishbreath]

Maybe it is but those Russian pilots clearly don't have time to "stabilize the chopper on all axii and the collective" before click-releasing the Trim repeatedly and often, so if we have to in the sim it seems there must be a bug in the simulation surely?

 

The one video everyone always bandies about shows the Russian pilots clicking the trimmer several times per second while maneuvering. It's pretty much impossible to do that without a force feedback stick.

 

The oversteering effect happens because the autopilot tries to correct pilot inputs back to the commanded attitude. The autopilot's inputs are proportional to the amount of deviation from the commanded attitude. If you're trimming fast enough, I imagine you wouldn't see the oversteer effect, or rather that it would be small enough so that you can work with it.

 

Edit: I don't have any inside source which can tell me whether it's modeled completely correctly, but I do know that it's modeled consistently and fully explained by the fact that the Ka-50's pilot controls and autopilot don't share information beyond the autopilot disconnect/disable on the trimmer. I'm no ED cheerleader, but they have high standards when it comes to this sort of thing, and I wouldn't expect that the ultimate answer is outside of these two possibilities: 1) it's modeled correctly or 2) the Russian military wanted it modeled incorrectly in this way for public release.

Edited February 12, 2014 by Fishbreath

[tsumikae]

There seems to be some misconceptions about the FD mode.I may be wrong, but I took both from the manual and experience that if his mode does, indeed, nullify all AP stabilizations engaged, it still receive inputs from them. It is not an override button. With FD mode on, you get to see a visual of the most recent inputs on your hud, that directly depends on the AP functions currently engaged. It also considerably smooth your inputs on the stick, again depending on what AP channels are active.

 

Trimming in FD mode still have a strong impact on your helo behaviour.

 

This may be the reason why some would think FD mode is "trying to kill you". It's not.

Edited February 12, 2014 by tsumikae