Trim...again.

[Frederf]

but there's a major issue. The rudder is still trimmed in the non-FFB way and that means after some trimming it isn't centered in the Ka-50 while it is below my desk.

 

The trim-then-center zones for each axis are configurable via LUA edits which should mean you can should be able to make the "Ok I'm centered after trim" window super large, even from -100% to +100% so centering is instant.

 

However if you have a real FFB cyclic then I don't know why you don't use the old style trim scheme (pre-patch) which doesn't require recentering. I guess it would depend on your preference for the pedals.

 

Apart from that issue I just wonder why it needs huge amount of rudder to keep the ball centered in a straight flight with coax rotors (even with all AP channels on). I don't know the exact physics but I'd like to know why it still slips like hell then.

I believe forward motion makes one side of the top rotor (advancing) generate a heck of a lot more lift than the other side of the rotor (retreating). More lift = more drag = pulls to that side. I think because one rotor is on top and the other is below that the one in "clean air" generates more lift so its pull is stronger.

 

A third thing I found strange while hovering is the fact that the Shark always flips over backwards with a neutralized trim. I've got to trim it a bit forward first to keep it where I want it. This is not documented at all. The lessons and the manual just say like "kick in the Hover Autopilot and there you go". I've always 20-30km/h backwards speed without using the trim to compensate for that.

You're not using "Reset trim to center" are you? That's a fictional command for the sim that's not in the real aircraft which will definately give you abrupt movement when used. Trim at 0/0 and trim for hover are not necessarily the same thing. Don't assume that a trim reset to 0/0 is anywhere near what's required to hover.

 

Auto-hover is best used to hold a hover from a hovering state. It is not good for getting to a hover while moving. If you engage autohover while moving forward not only will the AP try to bring the aircraft back to the spot in memory where the autohover was engaged. In other words it will try to recenter the HSI autohover crosshairs even if that point is behind you.

Edited December 7, 2009 by Frederf

[Eldur]

The stick is fine and it doesn't matter if I use the new or the old method. It's just the rudder. The point is, for example I'm hovering and pointing to 90°. Now I use right rudder to get it to 180°. Then, to prevent it from turning back to 90° I press the trimmer once shortly. What happens now is that the initial rudder input I gave to get there is added while I'm still pressing the right pedal. When I center my pedals it keeps turning right. Just to show the effect more clearly, get in a hover, push rudder a little bit into one direction and then push the trimmer often while you hold the rudder. Eventually it will be trimmed to it's max. deflection. And now without looking at the RCtrl+Enter figure I don't know where the center is to get it back there.

I can just do one thing not to get the problem: While having my new direction, press trim and hold it, release rudder pedals and THEN release trim. Problem here is that while I hold the trim, the Auto Hover is off. I can do so in a hover, but not in flight. Only solution there: Don't use rudder when trimming. And that's bad.

 

And I don't use Hover to get into it. I do so without and then activate it. The backwards issue is most apparent when taking off. I already roughly know how far I have to push the stick forward and trim it there not to flip backwards on lifting off. But I had to find this out first without any hint from the documentation. And I would believe that a helicopter is trimmed neutral to hover without any input with the AP channels and Hover mode on. But it isn't, as it needs slight forward pressure on the stick (= trimmed forward a bit) to stay there.

[Frederf]

I edited above to be "preference for rudder pedals." Of course stick is fine with FFB mode since the two trimmer logics don't really apply at all.

 

Ah I know that issue.

 

Possibility #1: Trimming in that extra right pedal when you turn in a hover and adding too much. It takes more rudder to change heading than to hold the new heading. After changing heading relax some back to center and hold that new heading with just your feet for 1-2 seconds. Then trim and AP 20% should easily hold heading. If you do this too quickly you can trim in too much rudder by accident.

 

Possibility #2: When you release trim it captures a new heading for heading hold right? WRONG! Ok, not wrong but it does not do it 100% of the time. Depending on your navigation systems modes, DH-DT switch, etc sometimes the heading hold heading is locked to the navigation point and not to the heading you were at when you released trim button. Watch the diamond on the HUD and make sure it updates when you release the trimmer. If it doesn't that means you are in a special locked-heading-hold mode. Putting the DH-DT switch to the middle position means you are never in a locked mode.

 

Possibility #3: You were yawing at >3° per second when you captured the heading. The autopilot will keep your yaw rate (so you keep spinning) if you capture when the heading is changing by more than 3° per second.

Edited December 7, 2009 by Frederf

[Tango]

While what you say is true in part you still must work within the stiff limitations of your environment. The real Ka50 FCS was never designed with the X52 in mind. Watch the split screen demo video (not the cool Frazier track but the real video). I don't recall ever seeing the pilot press and hold the trim. He didn't need to because he was working with the real cyclic attached to real actuators which are in turn attached to real AP servos. By using the FD or by holding the trim, WE are overcoming our limitations to achieve as best we can HIS controllability. That's the ultimate use of a "study sim" IMO.

 

Smokin' Hole

I've seen this video, and agree entirely.

 

The whole problem with our setups is the return-to-center sticks. By trimming then returning to center, you immediately restricted your aft/right roll travel.

 

The trim-then-center zones for each axis are configurable via LUA edits which should mean you can should be able to make the "Ok I'm centered after trim" window super large, even from -100% to +100% so centering is instant.

Great to know! Getting some pedals soon and don't want to have to keep returning those to center.

 

Best regards,

Tango.

Edited December 7, 2009 by Tango

[ddahlstrom]

May I ask what Lua file, and what setting this is?

[Frederf]

DCS\Scripts\Aircrafts\_Common\FMOptions.lua

[Bisch]

Neverending story I guess... after a long break in BlackShark.... what is the suggested way to trim if you use a FFB-Stick along with non-FFB-Pedals (should apply to almost any FFB-Stick user; use of pedals/twist/rocker as pedal input shouldnt make a difference either)?

 

My friends and I started with lots of problems using our MS FFB2 / Saitek Combo until we found out that you have to change the controls in the settings according to the FAQs. Triming the cyclic finally seemed to work. But the pedal problem mentioned in the posts in here above is still sth to worry about. I know why it is a problem but I didnt understand yet what the best solution is. I have three options in mind:

 

1. If you release the pedals before clicking the trim button it should have no impact (perhaps slight calibration issues with pedal axis could lead to cumulative pedal input? no axis sensor is in perfect balanced state when released, is it?) on pedal trim/input, but it makes trimming more complicated while not using it in the way it is meant to be. The BlackShark is not fully trimed after using trim.

 

2. Keeping the trim button pressed like the non-FFB-pilots to give you the time to release the pedals. Not only sad to lose an advantage of FFB but also quite difficult - at least to me. When pressing the trim button, no forces are applied to the MS FFB2 which makes me suddenly oversteer the stick even when only using clicks.... but with keeping trim pressed I need to worry about not moving the stick into any direction as long as the trim button is pressed. Quite difficult with the wishy-washy stick (as I said, no forces on the stick while trim button is pressed).

 

3. Don't use trim at all... meh....

 

So how I am supposed to do it?

[Frederf]

1. There is this thing called "deadzone" so even small variations around the center of the axis can be transformed into identical 0s. Besides even if you got "0 trim creep" you could still undo that with a major rudder trimming. Trim is so fluid that who would care?

[Bisch]

Thanks for your suggestion. I guess I ll do that... and generally trim not so often as others do. So far I dont think I miss too much. Releasing pedals screws my cruise flight so keeping trim rare should be the best idea for me.

However, is there no way to completley disable (exclude) trim for pedals? That way I could forget about releasing at least