Stable hover check with/without trim?

[Wyverex]

Hi all,

 

I would appreciate some advice regarding a stable position while doing the hover check. I find it pretty tough to keep the heli hovering in one position without engaging the hover hold mode.

 

After a lot of practice I think I found a way to do hold it more or less stable just by pushing the cyclic gently in one direction or another BUT as soon as I trim the bird, I immediately lose the position because the nose will dive or rise.

 

Now I'm asking myself: Can it be done to trim the heli in such a way that you can essentially release your hand from the cyclic while hovering 3 meters above the ground WITHOUT hover hold mode? Or can't this be done with a helicopter? I think I read somewhere that they are always unstable while hovering (though I've digested so much information the last three days that it gets hard to keep track now...).

 

If this is possible I'd really appreciate a track showing this (preferably also showing the input window). :)

 

Cheers

 

P.S: I have AP engaged (Pitch, Bank & Heading)

[MTFDarkEagle]

Hi!

 

Yep, perfectly possible. Practice, practice, practice. Once you're done practicing, maybe some more practice. Did I mention practice yet? :D

 

I can't make a track now, but I'll see if I can make one soon (if not someone else beats me to it).

 

Hope this helps in some way though, for now.

 

P.s. Keep practicing!

[Bucic]

The case you're asking to be confirmed is actually a fundamental function of trim system i.e. it makes stable flight/hover easier. Simply put:

pilot manages to 'calm helicopter' to a stable flight/hover -> so stable that he does only small controls inputs for corrections -> !TRIM! -> forces on the stick are zeroed for that position (that position is the new stick neutrum)

 

And... that's all. In general the only thing that changes is that pilot doesn't have to wrestle with the stick anymore (let's leave AP for now for the sake of simplification). Think that RL scenario through and the only difficulty ahead of you will be choosing one of the two in-game trimming methods and practice.

Edited December 23, 2011 by Bucic

[AlphaOneSix]

You can achieve a stable hover within an air mass, but that normally won't be a stable hover over a point on the ground. To trim to a perfectly stable hover over a point on the ground, you'll need an absolute no-wind condition, which is rare in most missions I believe.

[Wyverex]

You can achieve a stable hover within an air mass, but that normally won't be a stable hover over a point on the ground. To trim to a perfectly stable hover over a point on the ground, you'll need an absolute no-wind condition, which is rare in most missions I believe.

 

That's what I mean. I can stabilize the heli (with manual input) but to keep it over the same point on the ground requires constant attention on my side. I'm practicing with the Take-Off in Beslan mission and it definitely has wind. I'm fully aware that this requires a lot of practice.

 

But what I actually find annoying is that as soon as I have stabilized the position and then press trim, I lose the position immediately since the stick moves a bit and my carefully balanced attitude is screwed. I should note that I use a G940 with FFB. I'd really like to know if that's just a calibration problem on my side or if everyone has it.

 

EDIT:

Please have a look the attached track. In the first part I just try to keep the heli from moving. I trim a couple of times. Note that each time I immediately let go of my stick. Observe that the heli starts moving into an unwanted direction. In the second part I show what might be the root cause. Take a look at the input window. I also trim a couple of times and let go of the stick afterwards. Note that the caret "jumps" in another direction. I already tried to minimize that jump by extensive calibration but I can't seem to get rid of it. So am I the only one with that behavior?

hover.trk

Edited December 23, 2011 by Wyverex
Added track

[Devrim]

That issue is annoying me too.

 

I take off slowly (no wind!) up to 100 meters. And engage the hover function (without trim).

Ok first, she stables on a point. But later, drifts backward with 8-10 km/s.

 

When even I try to hit a tank with Shkval (Auto Turn & Hover modes on), she drifts back continuously. Is that normal? And should I trim and manage %100 stable flight first?

[Wyverex]

Devrim, I'm talking about a different issue as can be seen in the track I provided. I specifically DO NOT engage the hover mode as the point is to learn to hover above a given point on the ground on my own.

 

But as to your point I noticed that for the hover mode to work as expected you have to stop the heli before activating it, otherwise it might just keep drifting.

[Xxx]

I think DarkEagle's point about practice is valid!

 

Remember we are trying to fly this helicopter just using one physical sense, that of sight! We have no perception of true flight, as our balance is firmly planted in our backside, which is parked in a comfy computer chair.( Unless you are lucky enough to own a full motion platform!)

http://www.flightemotion.com/

 

Please, Santa can I have one for Xmas?:D

[Smokin Hole]

Don't forget also that where you look is important. My advice, keep the door open and look 45 degrees to your left. Land with the door open, especially when landing on a friget. Small corrections and you'll get it.

[Wyverex]

Thanks for all your input but maybe I haven't made clear where my problem lies. I'll try again :)

 

I hover about 2 - 3 meters above the ground and try to hold the helo in position just using the cyclic (no trimming yet). Yes, this requires practice. And I'm already practicing that a lot. So far no problem (just lack of practice).

 

Now I have the assumption that when having found a fairly stable position (almost no drift in any direction), pressing the trim button should stabilize that position, meaning after that you have to give even less input to hold that position.

 

If this assumption is correct then I suppose my G940 is either broken or misconfigured because when pressing the trim button (in a quite stable position!), the helo immediately drops away in some other direction and then it's even more work to recover.

 

In some other threads I also read that there seem to be problems related to FFB sticks and slight position changes of the stick after trimming, so this could be a similar symptom.

 

So all I'm asking is to kindly watch the track I attached above and give feedback on whether this input behavior is nomal, I'd really appreciate that! :)

Edited December 23, 2011 by Wyverex
Typos

[Luigi Gorgonzola]

Please keep in mind that you're actually dealing with two systems when hitting the trim button:

 

Trim -- removes all forces on cyclic and rudder, thus easing a pilot's life (that's the clicking sound you hear)

 

Attitude Hold -- determines the helicopters current attitude in space and stores the resulting values in the flight control system which is then (within certain limits) modifying the pilot's input to match the attitude determined when the trim button was hit.

 

Result: If the helicopter's attitude does not match the pilot's intention, the helicopter wins. This is often described as "strange behaviour" or "trim is broken".

 

As you can switch off the Attitude Hold system by engaging the Flight Director Mode, it seems advisable to do so in training situation when the intention is to actively control the aircraft.

 

IRL, most definately every pilot would use "Auto Hover" (or "Hover Hold" in our case) to keep a hover attitude. It doesn't make any sense -- again, except of training situations -- to "waste" precious pilot attention to maintain a desired attitude if there's a system doing the job at least as good as the pilot, usually even better. ;)

[OGREMAN]

BlackShark2 what happened to the trim & AutoHover?

 

Absolutely love Black Shark2 .... BUT! (why must there always be a BUT?)

 

1)The trimmer reaction is now severely adverse.... I normally use in BS1 the "auto centre" setting in options as off and when attempting to trim for a particular airspeed BS2 with the same setting selected now reacts by an extreme dive at the ground that is outside of the range of the stick (un correctable) resulting in certain crash.....

 

2)The auto hover is now frequently overwhelmed by even minor winds making it a liability... the result is that I now have to "augment" the auto hover with manual added correction or simply use manual hovering. Attempting to re-trim while in auto hover to correct for slight drift will compound the drift correction error.

 

To summarise ... while its great that the key bindings/settings allow BS2 to work as BS1 there is definately something wrong with the trim and hover functions.

Edited December 23, 2011 by OGREMAN
Addition

[tobyeez]

I also have the G940 and the trimmer absolutely deoes not act the same as it did in BS1. The nose keeps wanting to go down.

[OGREMAN]

I have the same issue and I regularly fly BS1 now BS2 for 3or more hours a day.... fact is the trimmer in BS2 behaves much less predictably and often radicaly different from the identicle setting in BS1. In all likelyhood its not your techneque or hardware its the upgrade version has totally different behaviour.

Edited December 23, 2011 by OGREMAN

[Jona33]

Are you pressing trim and then releasing all controls including rudder within 0.5 seconds?

 

Thanks for all your input but maybe I haven't made clear where my problem lies. I'll try again :)

 

I hover about 2 - 3 meters above the ground and try to hold the helo in position just using the cyclic (no trimming yet). Yes, this requires practice. And I'm already practicing that a lot. So far no problem (just lack of practice).

 

Now I have the assumption that when having found a fairly stable position (almost no drift in any direction), pressing the trim button should stabilize that position, meaning after that you have to give even less input to hold that position.

 

If this assumption is correct then I suppose my G940 is either broken or misconfigured because when pressing the trim button (in a quite stable position!), the helo immediately drops away in some other direction and then it's even more work to recover.

 

In some other threads I also read that there seem to be problems related to FFB sticks and slight position changes of the stick after trimming, so this could be a similar symptom.

 

So all I'm asking is to kindly watch the track I attached above and give feedback on whether this input behavior is nomal, I'd really appreciate that! :)

[Wyverex]

As already written above, the G940 is an FFB joystick, so I do not have to release the joystick in that timeframe because it stays where it is (more or less, that's part of the problem). I DID take my hand from it in the track though to show what happens afterwards.

 

Anyone watched the track yet? I'm still very curious about that jump in the input window.

[Bucic]

I think DarkEagle's point about practice is valid!

 

Remember we are trying to fly this helicopter just using one physical sense, that of sight! We have no perception of true flight...

This is why in a sim you make sure you have lots of points of references during flight. Practice hover near airfield lamp towers etc., set up some cloudy weather if you go higher, have your wingman flying around.

[Smokin Hole]

I have a G940 and see a huge improvement with trim functionality since the 1.1.1.1 patch. But I still sometimes have to trick it. I generally trim slightly more aft stick than is needed because otherwise the help will pitch down slightly in a hands-off hover. Other than that, it works perfectly. But I can now fly with the AP on (FD off) and this was never the case before.

[Kite]

That s normal that when you trim you will sink or pitch a little

what I do is the first trim give a lot of pitch or sink.

then I correct again and trim little than before. Then it sink less. Correct again little and trim again avery time making smaller movement. The final little little little trim will give you stable hover. Face to wind... Remember otherwise you will have lateral shift.