Don't Mention the T Word

[MeerCaT]

"Trim!" - there I said it.

Nobody wants to hear it, I know, but it had to be said and now we can all move on with our lives.

 

Now then, for the only two people continuing to read this thread I would like to share a short flight 'track' (and accompanying bare-bones mission file) I have recorded. [see attached]

 

If you watch this track I would love to hear back from you regarding how this compares with your own experiences of the beloved trim mechanism.

 

Of course any general tips/comments on my flying will be greatly recieved, but the purpose of the flight was to probe and analyse the mechanism-that-cannot-be-named.

 

During the flight I repeatedly hold a (fairly?) steady attitude, with either the nose up gently, nose down gently or banking gently. While holding the steady attitude I 'tap' the you-know-what button.

 

All documentation (that I've ever come across at least - PDF manual and numerous forum postings) indicate the following actions will occur at this point:

...<skip technical details that we are all too familar with by now>...

- the physical position of the (in-game) cyclic and pedals are maintained ('fixed' if you like)

- the auto pilot system(s) will attempt to maintain the current attitude (or rate of turn, if appropriate) within a certain limit of control authority (20%).

 

 

From the track, you might observe that each time the T button is 'clicked' the helicopter is being held at a pretty stable attitude. So once the cyclic and pedals have been fixed in place by the T mechanism, the autopilot shouldn't really have very much work to do (if any) to maintain the attitude.

 

However, for reasons I am here to discover, the autopilot is seeing fit to provide some additional input, which I don't believe is at all necessary.

 

Each time the T button is clicked I quickly return my (non-force feedback) joystick controller to neutral. Yet in the track you may see that (aside from the small 'bump' effect caused by not returning my controller to neutral quick enough) the helicopter is lurching to a greater or lesser degree further in the direction of the current attitude.

 

For example, holding a gentle nose-down attitude and clicking the T button results in an overly exaggerated nose down attitude. ('Bump' effect exluded).

The extent to which this exaggeration takes effect seems to be somewhat proportional to the extent of deviation of the current attitude from the 'level' attitude.

 

Does anyone else observe this when watching that track, or experience it during their own flight?

 

This effect seems much more pronounced in Black Shark 2 than I remember it being in Black Shark 1 (which I have now uninstalled).

In BS1 I don't remember experiencing any significant struggle using the 'T' mechanism but in BS2 I feel in constant battle against this 'exaggeration' effect.

 

I can get a little frustrated with it, not because it is difficult but more because I simply don't understand the cause of the effect; and the reason for not understanding is because the observed behaviour does not correspond to the documented behaviour of the mechanism.

 

If the pilot is already holding a steady attitude, then why when 'T'-ing would the autopilot think it necessary to provide ANY additional input whatsoever? The 'locking' of the cyclic and pedals is clearly all that is necessary to maintain the attitiude (assuming no change in external forces, such as wind strength/direction) because that is all the pilot was doing before he/she unwisely chose to press the "random attitude" button :)

 

 

Basically, my subconsious expectation of the T behaviour that was built up during 50+ hours in BS1 does not feel applicable to BS2.

What makes it feel worse is that I am struggling to build up a new subconsious model of expectation for the new behaviour.

 

Is it really just a case of putting in the hours to train my brain on this?

Or are there a few golden nuggets of information that I am missing to complete the puzzle?

 

Thanks all.

 

 

My Controls:

- Saitek X54 "Flight Control System" (not a force feedback controller)

- Saitek "Pro Flight Rudder Pedals"

ToyingWithTrim3.trk

TrimTesting.miz

[Skkuda]

Thank god!

I was afraid to start looking like a "its a placebo effect, nothing was changed"

I lack the capacity to express in English as you, but enough to me to say Trim in BS2 its different than BS 1.02:joystick:

Cheers

[Luigi Gorgonzola]

IIRC it had been discovered that the mechanism-that-cannot-be-named ist being updated on button-that-shall-not-be-mentioned press instead of release. Also IIRC, this is supposed to be fixed soon™ Maybe this is an explanation for the symptoms-you-imagine-to-encounter?

 

Until then, I will strongly attempt to refrain from looking into any further thread covering the topic-that-cannot-be-named. It simply drives me crazy :wacko:

[159th_Viper]

Also IIRC, this is supposed to be fixed soon™

 

Pending fix relates to FFB sticky only.

[Luigi Gorgonzola]

Pending fix relates to FFB sticky only.

Wot? So Non-FFB users will still experience these symptoms? Weren't there quite some who described the same or similar behaviour in the original thread?

[BaD CrC]

Understand what you meant MeerCaT. It's true the behavior of the BS2 trim is really disturbing and different from BS1. I loved the option ED added in 1.02 to wait for the stick to go back to central position before applying the trim, but I don't understand how it is supposed to work now. Everytime I trim then go back to central position, got a violent pitch up or down movement from my aircraft.

[MeerCaT]

I want to be very careful we do not confuse the issue, so I would just like to make it very clear that we are talking here about non-force feedback controllers only.

 

I stress this point because I understand there is a known issue that relates only to force feedback controllers. So I think it is important we keep threads completely separate for the two types of contoller.

[159th_Viper]

I want to be very careful we do not confuse the issue, so I would just like to make it very clear that we are talking here about non-force feedback controllers only.....

 

Understanding the distinction between the controllers might shed light on the issues experienced, but that's a discussion again for another thread - I'm still pondering myself in a bid to better understand :)

 

In any event, back on topic: At the outset I must state that my reply following is merely informative and must please not be construed as 'Do it my way or else' or 'It's the only way' etc etc - just another way which, upon analysis, might contribute to the discussion.

 

Re your track, took control immediately after your very first trim input at mission-start and flew as follows:

 

# - Approx 8 trim inputs to establish a 10m/s+ climb rate.

 

# - Trim to level off.

 

# - Approx 6 trim inputs to establish 10m/s descent rate.

 

# - Trim to level off.

 

# - Fooled about under the bridges at 30 degree bank whilst trimming for speed.

 

# - Commenced RTB, trimmed out accumulated errors, trimmed for 8m/s climb rate.

 

# - Levelled out and trimmed for descent, landed.

 

What I took out of the above is that small, continuous trim inputs to establish a wanted attitude works for me.

 

Is it the only way?

 

Most definitely Not!

 

It does however work for me and seems to in sync with the footage in other threads that small, constant trim inputs mirror equally small attitude adjustments to keep the Helo happy. Pay little attention to my rudder-trim issues - my pedals are a tad sensitive which leads to over-correction and as such not indicative of SIM behaviour but rather user-error on my part.

 

In any event, as said, merely another way to skin this particular cat it would seem :)

 

Track: ToyingWithTrim3 Control.trk

Edited December 2, 2011 by 159th_Viper

[WildBillKelsoe]

"Trim!" - there I said it.

Nobody wants to hear it, I know, but it had to be said and now we can all move on with our lives.

 

Now then, for the only two people continuing to read this thread I would like to share a short flight 'track' (and accompanying bare-bones mission file) I have recorded. [see attached]

 

If you watch this track I would love to hear back from you regarding how this compares with your own experiences of the beloved trim mechanism.

 

Of course any general tips/comments on my flying will be greatly recieved, but the purpose of the flight was to probe and analyse the mechanism-that-cannot-be-named.

 

During the flight I repeatedly hold a (fairly?) steady attitude, with either the nose up gently, nose down gently or banking gently. While holding the steady attitude I 'tap' the you-know-what button.

 

All documentation (that I've ever come across at least - PDF manual and numerous forum postings) indicate the following actions will occur at this point:

...<skip technical details that we are all too familar with by now>...

- the physical position of the (in-game) cyclic and pedals are maintained ('fixed' if you like)

- the auto pilot system(s) will attempt to maintain the current attitude (or rate of turn, if appropriate) within a certain limit of control authority (20%).

 

 

From the track, you might observe that each time the T button is 'clicked' the helicopter is being held at a pretty stable attitude. So once the cyclic and pedals have been fixed in place by the T mechanism, the autopilot shouldn't really have very much work to do (if any) to maintain the attitude.

 

However, for reasons I am here to discover, the autopilot is seeing fit to provide some additional input, which I don't believe is at all necessary.

 

Each time the T button is clicked I quickly return my (non-force feedback) joystick controller to neutral. Yet in the track you may see that (aside from the small 'bump' effect caused by not returning my controller to neutral quick enough) the helicopter is lurching to a greater or lesser degree further in the direction of the current attitude.

 

For example, holding a gentle nose-down attitude and clicking the T button results in an overly exaggerated nose down attitude. ('Bump' effect exluded).

The extent to which this exaggeration takes effect seems to be somewhat proportional to the extent of deviation of the current attitude from the 'level' attitude.

 

Does anyone else observe this when watching that track, or experience it during their own flight?

 

This effect seems much more pronounced in Black Shark 2 than I remember it being in Black Shark 1 (which I have now uninstalled).

In BS1 I don't remember experiencing any significant struggle using the 'T' mechanism but in BS2 I feel in constant battle against this 'exaggeration' effect.

 

I can get a little frustrated with it, not because it is difficult but more because I simply don't understand the cause of the effect; and the reason for not understanding is because the observed behaviour does not correspond to the documented behaviour of the mechanism.

 

If the pilot is already holding a steady attitude, then why when 'T'-ing would the autopilot think it necessary to provide ANY additional input whatsoever? The 'locking' of the cyclic and pedals is clearly all that is necessary to maintain the attitiude (assuming no change in external forces, such as wind strength/direction) because that is all the pilot was doing before he/she unwisely chose to press the "random attitude" button :)

 

 

Basically, my subconsious expectation of the T behaviour that was built up during 50+ hours in BS1 does not feel applicable to BS2.

What makes it feel worse is that I am struggling to build up a new subconsious model of expectation for the new behaviour.

 

Is it really just a case of putting in the hours to train my brain on this?

Or are there a few golden nuggets of information that I am missing to complete the puzzle?

 

Thanks all.

 

 

My Controls:

- Saitek X54 "Flight Control System" (not a force feedback controller)

- Saitek "Pro Flight Rudder Pedals"

 

Tits :D

[Kite]

cannot-say-it-but-yes-same-to-me-with-x52-completely-different-trim method from bs1

fighting-to-have-level-flight all day long. sigh... but i love bs and i will fight this dam mr. "T" !!! :-)

[Xxx]

I "borrowed" this from PeterP on the Problems thread.

 

 

It illustrates the way I fly the Ka 50. After every small Cyclic input "Trim" Click and release Cyclic back to centre. If you listen to the guy in the vid he is "trimmin" like twice per second.

 

Just a thought.:joystick:

[bluepilot76]

In the (famous/fabulous) YouTube Kamov Ka-50 Cockpit view video, the guy only trims something like 8 times through the whole transition from sitting on the ground to airborne, to changing course as well as changing altitdes and speeds, so I think that trimming after every small movement of the cyclic might be a bit much? I dont see any of those big bumps in the video.

[StoOopiD]

i blame it on the rudder axis. its bugged.

 

the trim works perfectly when u un-bind the rudder axis?

 

try it.

[159th_Viper]

In the (famous/fabulous) YouTube Kamov Ka-50 Cockpit view video, the guy only trims something like 8 times through the whole transition from sitting on the ground to airborne, to changing course as well as changing altitdes and speeds.....

 

He climbed from take-off straight up to his flight altitude of approx 100m AGL and thereafter trimmed for level flight - no need to trim any more than he did. He did not deviate to any great extent from his flight parameters which would have necessitated further trim input.

 

 

so I think that trimming after every small movement of the cyclic might be a bit much?

 

Depending on what you want to do, definitely not, as illustrated in the cockpit-trainer vid. Especially relevant in changing altitude at speed.

 

I dont see any of those big bumps in the video.

 

Quite so - his attitude adjustments were sufficiently small, followed by immediate trim input.

[bluepilot76]

He climbed from take-off straight up to his flight altitude of approx 100m AGL and thereafter trimmed for level flight - no need to trim any more than he did. He did not deviate to any great extent from his flight parameters which would have necessitated further trim input.

 

 

 

 

Depending on what you want to do, definitely not, as illustrated in the cockpit-trainer vid. Especially relevant in changing altitude at speed.

 

 

 

Quite so - his attitude adjustments were sufficiently small, followed by immediate trim input.

 

The one I have been watching, I seem to recall he climbs, side slips a bit , swings the nose through 90 degrees whilst accelerating, climbs more, turns about 90 degrees again, accelerates more, climbs more.

 

I wouldnt say the attitude adjustments were small, see above, some of those manoevres have huge gaps in trimmer use. The only time it really calms down is when he gets onto course at altitude, after turning along the road. Then of course he hardly has to touch anything because the AP is holding required trajectory.

 

Is there any other good KA50 in cockipt videos, I couldnt find any?

[bluepilot76]

Who mentioned the T word anyway! dammit I hope it wasnt me!

[bluepilot76]

Quite so - his attitude adjustments were sufficiently small, followed by immediate trim input.

 

I would just like to add, that I was impressed by the precision of the OPs flying. I think he quite clearly demonstrated the problem. In my opinion his attitude adjustments were not as big or abrupt as the guy taking off in the Kamov video.

[genbrien]

I "borrowed" this from PeterP on the Problems thread.

 

 

It illustrates the way I fly the Ka 50. After every small Cyclic input "Trim" Click and release Cyclic back to centre. If you listen to the guy in the vid he is "trimmin" like twice per second.

 

Just a thought.:joystick:

 

woah... so much ''click'' !!!:joystick:

Is there a way to trim that fast if you dont have a FFB joystick?

[bluepilot76]

woah... so much ''click'' !!!:joystick:

Is there a way to trim that fast if you dont have a FFB joystick?

 

Yeah there is, but if I told you I'd have to kill you...

Carrier landing.trk

[MeerCaT]

Firstly, Viper thanks for taking the time that you did, and kudos for the bridge stunt. (You just had to out do my powerlines piece didn't you!)

 

But let me shake some of that brown off my nose by pointing out how I noticed you shyed away from the 'random attitude' button during your bridge and landing manouvres; and baiscally anytime that the safety of your neglected but nevertheless valued bottom requires the ability to control the beast in a predicable, logical and intricate manner.

What, don't you trust your nameless-mechanism to not give you an imprompu face-to-floor meeting at these delicate times?

 

<commence tongue out procedue; deploy raspberries...>

 

(You know I'm just kidding right? ...your bottom isn't really that valuable!)

 

 

Never one to pass up the opportunity for a good tangent - this topic has got me thinking about the various flight modes of the BlackShark and how they apply to the many different flying situations.

 

The way I see it, any given flight will contain one or more of the following 'situations/stages/phases/modes':

 

1. Simple travel (straight line or curved) between two points (long or short distance)
   
2. Medium-long distance flight path following
   
3. Intricate, precision and delicate manouvering; such as: takeoff, landing, positioning relative to environment/objects, etc.
   
4. Fast-paced abrupt manouvering; such as emergencies and acrobatics
   
5. Hovering (although technically could classify as an 'intricate precision' situation, it is worthy of it's own category I feel)
   
6. <completely skipping over more detailed combat activities>
   
7. ...you could think of more I'm sure...
   

 

Now let's consider the different flight 'modes' of our lovely Shark:

 

1. 'naked/raw' - no computer aided control whatsoever (for those that like to rock and roll!...and have a penchant for eating dirt)
   
2. Pitch, Bank, Heading 'damping' (let's throw in Altitude as well). I am tempted to call this "normal" just for the sake of giving it a name, but I feel so dirty doing so. I'll call it "damp" instead. 'Moist' if you will. Yes, definitely moist mode. Effective whenever trimming is not active
   
3. Pitch, Bank, Heading 'holding' - Takes effect while trimming is in place and active
   
4. Flight Director (FD)
   
5. Autopilot Route
   
6. Auto Hover
   
7. Descent
   
8. Shkval yaw (auto turn to target) - this is more of a combat-based mode. Let's ignore it for now. Guns 'an that, Pah! Have a daisy for your hair. Love thy neighbour man! ... he said what about my mum?! Doris, fetch me my Vihkrs! (No not my "slippers"!!)
   

 

Ok, so when (situation) to use what (flight mode)?

Here's how I would marry the two lists together:

 

• Mode: Raw
  
  • Situation: No. Never. Don't do it. Naughty. Bad boy. Sit Booboo, sit.
    

   

  [*]Mode: Normal ...no, Moist ...no, Damping

  • Trim, trim and ...what was the 3rd one? Oh, and trim again. While trim is active this simple damping-only mode isn't, and since we fly at ALL times in a trimmed state this mode will hardly ever be in effect. (Depending on ones trim strategy). Not used - by me.
    

   

  [*]Mode: Holding

  • Situation: 1) Simple travel
    

   

  [*]Mode: Flight Director

  • Situation: 2) Flight path (maybe, sometimes), 3) Intricate, 4) fast-paced (emergency, acrobatics, and general arzing about. In fact I would like to petition to have the label on the FD button changed to reflect this. We can use an abreviation of "eaga", or perhaps simply "arze"?)
    

   

  [*]Mode: Route

  • Situation: 2) Flight Path
    

   

  [*]Mode: Hover

  • Situation: 3) Intricate, 5) Hovering
    

   

  [*]Mode: Descent

  • Situation: 3) Intricate, 5) Hovering
    

   

 

 

 

Side note: bluepilot, what is this famous youtube video thou doth speak of?

[159th_Viper]

In my opinion his attitude adjustments were not as big or abrupt as the guy taking off in the Kamov video.

 

You need to analyse the vid again :)

 

The OP, with his third trim input illustrating the 'bump', engaged trim whilst in a 11m/s climb rate at a pitch angle of 10 degrees. It took me 8 trim-presses to trim properly for a 11m/s climb. The Pilot in the RL Kamov vid established trim for an approximate climb rate of 1m/s, a tenth of what the OP was trimming for.

 

Above is just one example clearly evident after a wee bit of careful analysis.

 

 

I noticed you shyed away from the 'random attitude' button during your bridge and landing manouvres; and baiscally anytime that the safety of your neglected but nevertheless valued bottom requires the ability to control the beast in a predicable, logical and intricate manner.

What, don't you trust your nameless-mechanism to not give you an imprompu face-to-floor meeting at these delicate times?

 

Quite so - no reason to dabble in that button 'ol chap, provided you are properly set-up to begin with, ie free of any unwanted, nasty accumulated errors. As an illustration, herewith track illustrating the complete absence of trim provided the Helo is properly set up to begin with:

 

[ATTACH]59647[/ATTACH]

 

Absence of trim also clearly illustrated in the RL vid where pilot performs the aerobatics display from approx 3:30 in to the vid. You clearly see he trims for hover and thereafter sets off with the display with no trim input.

 

Herewith vid:

 

eq1kkvxAsd0

[bluepilot76]

Viper Im getting confused, not by flying the thing, I can see a logical method for doing so and am no longer having any further problems now that Im doing it "my way". However what is the official line; should we trim regularly or not? Maybe only when were not doing very much? What about through manoevres. At what point is it OK to just fly off trim through manoevres, and at what point should we trim 2 times a second?

 

Anyway since you asked, lets analyse that video.

 

Time 0.10.

The Kamov guy trims in hover at 012m with pitch +08 degs and hdg 120. He then side slips to right..Changes heading to 220 and reduces pitch to -18, whilst climbing to 090m and increasing speed to 91kmh before finally trimming again when he is pointing the trajectory he wants to go, at Time 0.24. Through the enroute phase, IIRC there are no significant changes in attitude when he trims onto a new trajectory.

 

Meanwhile out hero Meercat, in the first of his tests just after he zooms into the hud, 1) trims 2) changes pitch a "Meer" 10 degs then 3) trims again. As he releases the controls there is a further 10 degree pitch change. This is what he is complaioning about. It seems legitimate to me.

 

The "should you trim whilst flying manoevres argument" is OT I think. But Im happy to discuss it all day, Im on shift and getting paid to sit here for the next 12 hours!

[MeerCaT]

Thanks for the video. It's good to see the real life thing from the pilots view.

 

I notice in that video there is no heading 'diamind' on the HUD. I'd say the pilot perhaps has the heading AP channel switched off. (Though I hear real life pilots would always have these channels on).

Or is it maybe just a slightly different version of the HUD software to the one we see in game?

[Jona33]

Well given every single Ka-50, all 15 of them are basically upgrades to each other that's possible. Or he's not following the PVI. Another possibility.

[159th_Viper]

However what is the official line; should we trim regularly or not?

 

That's the thing - there is no 'official line'. As long as all of us are flying it our own way then there is no mandatory way of doing things. The most that we can do is attempt to replicate RL doctrine - if that is what we want to do - and that has it to trim often, as in the vids. What would further clarify the issue is if we had actual Kamov Pilot input in the debate. Until then, we have to rely on video footage alone.

 

And if that is not enough - we also have to rely on Non-FFB controllers vs the real deal, which further affects behaviour.

 

Time 0.10.

The Kamov guy trims in hover at 012m .........This is what he is complaioning about. It seems legitimate to me.

 

You are forgetting that MeerCat was in a 11m/s climb when he trimmed. He is trimming, telling the AP to maintain a 11m/s climb whilst at the same time wanting to keep the current attitude the instant he hits the Trim tab and not forgetting the previous AP setting - It's little wonder the Kamov attempts to climb further (10-degree pitch change) - that's what you told it to do. The Kamov pilot was nowhere near that - remember the 1m/s climb rate, at most.

 

Important also not to overlook the influence that the collective has when manoeuvring and trimming the Kamov. Easy to test yourself: Trim at a 5 degree pitch angle at a positive rate of climb vs Trim at a 5 degree pitch angle at a neutral rate of climb and note the difference.

 

 

The "should you trim whilst flying manoevres argument" is OT I think.

 

There is no argument if you have regard to one of the few sources we have at present: The real Pilot does not trim, ergo it's not necessary, provided you are set up correctly. In the absence of actual Pilot info, the RL footage is a wee bit more authoritative than our debate. Then again, my interpretation of the footage insofar as the absence of trim in the vid is concerned could also be fatally flawed. Times like this when I wished we had recourse to a SME, if only for my own peace-of-mind.

Edited December 3, 2011 by 159th_Viper