Pitching up while trimming in route mode.

[Itkovian]

Hi there,

 

I was doing some flying last night, the first real flying since BS2 came out (I've spent time re-learning the manual since BS2's release, but the Simming Gods were unkind to me until now), and I've got a question:

 

NOTE: I have a MSFFB2, and this isn't the old trimming loss-of-control routine, never had that issue with my trusty Force Feedback stick *grin*)

 

While I'm flying in route mode and trim the A/C to a new altitude and speed, the moment I release the trimmer the autopilot seems to immediately react by pitching up for a while before settling down (at a significantly lower speed and higher altitude that I trimmed for). Sometimes, in fact, it will start wobbling as it tries to stabilize itself because it pitched up too much and has to correct.

 

So what I end up doing when I release trim is maintaining a slight forward pressure on the stick to counteract the pitching, at which point the route AP settles down and the rest of the route is uneventful. But this will occur whenever I trim with route mode on (though to be honest, I didn't specifically test if this occurs with route mode off, I'll have to check that tonight).

 

Any thoughts on what might be causing this?

 

Thank you.

 

Itkovian

[Itkovian]

I think the route mode tries to keep the speed despite you trim, and you have to disengage it, change speed, and then re-enable it.

 

Really? so when I settle on a course and want to change the speed, I should disengage route mode, reach my new speed, trim, and then engage route mode?

 

That's strange, because the HUD clearly shows the new "set speed" when I trim. Is that somehow entirely independent from the route AP?

 

Itkovian

[Itkovian]

Oops, then I'm plain wrong.

 

I answered based on my experience that the ka-50 seems to refuse to change the speed while route mode is on. Very uncomfortable indeed.

 

So you're getting the same symptoms I am? I'll have to test what you're talking about, and double-check that I'm only having this issue with route mode on.

 

Itkovian

[StoOopiD]

since the 1111 patch i cant complain. as for the route mode, my blackshark wants to pitch down when i release the stick. so i keep triming intil i feel the weight shift towards the back of the stick, then i release, then the bs rocks alittle then stablizes. All APs on.

 

OP,

while ur in route mode, u must be going forward with the BS's noise pitched down, right? then u release the stick and then BS's noise pitches up. weird.

 

i remember reading somewhere bout how the forces on the MS FFB2 stick being backwards. try to flop the FFB axes in the in game FFB settings.

[Ramstein]

if you use trim in helos, it pitches when you release it,, I (and several other freinds)stopped dusing trim a year or two ago,, and don't have to deal with the trim problems.. makes flying much easier, it has a couple disadvantages like firing from altitudes a little higher than targets, while pitched down... so without pitch you must be more level with targets, small price to pay...

 

:joystick:

Edited February 2, 2012 by Ramstein

[PeterP]

 

While I'm flying in route mode and trim the A/C to a new altitude and speed, the moment I release the trimmer the autopilot seems to immediately react by pitching up for a while before settling down (at a significantly lower speed and higher altitude that I trimmed for). Sometimes, in fact, it will start wobbling as it tries to stabilize itself because it pitched up too much and has to correct.

 

So what I end up doing when I release trim is maintaining a slight forward pressure on the stick to counteract the pitching, at which point the route AP settles down and the rest of the route is uneventful. But this will occur whenever I trim with route mode on (though to be honest, I didn't specifically test if this occurs with route mode off, I'll have to check that tonight).

 

Any thoughts on what might be causing this?

 

Thank you.

 

Itkovian

 

 

Was the Alt-Hold channel on ?

Did you had a relative high nosed-down angle and compensated it with a higher collective pitch to keep level before trim release?

Did you set a new altitude with the collective brake?

From the manual:

Scale of Deviation from Assigned Radar Altitude. This index and scale appear when route mode is engaged with altitude hold. An assigned altitude is set each time you release the collective brake (see Collective stick description). After you reach the desired altitude you release the brake on the collective and the current altitude will be set as the Assigned Altitude. After that, the deviation index indicates deviation from Assigned Altitude in meters.

There are many factors that can cause this ...

 

I experienced this also some time - in both direction: pitch down or up - but I can clearly say that it was always my fault and I trimmed in a flight condition that was outside of what the AP could hold in route-mode.

 

So please post a Track showing this behaviour.

 

(I use also a MSFFB2)

Edited February 1, 2012 by PeterP

[Itkovian]

Actually, I flew again last night and this behavior occurs without the route mode (with the AP channels on, except the ALT HOLD channels).

 

For example, I'm flying along a given course (not using the route mode) and trim to the desire attitude, and the A/C will pitch up.

 

All I can think of is that there may be some slack in my MSFFB2 which allows minute movements that frequently translate into pitching up. If I maintain tight control after trim and ensure it stays pitched properly, I can let go of the stick and the pitch will remain stable.

 

It's still very unusual, however. I'll be doing some free flying to test it some more.

 

In reply to Ramstein: I use a Force Feedback stick, so my stick actually is supposed to behave like the real cyclic, in that trim will "freeze" the stick in its current position (so if I'm pushing the cyclic forward and to the left and trim, the motors will keep the stick in that position even if I stop applying force). Most problems people have with trim are due to having non-FFB sticks, which requires you to quickly center your stick as trimming sets a new "neutral" position.

 

Point is, I shouldn't be getting this behavior with a FFB stick, at least not with Alt Hold off.

 

PeterP: So you're saying that w/ the Alt Hold channel on, the set altitude is NOT determined by trimming, but rather by the collective brake?

 

I've never used the collective brake to be honest, and I always thought desired altitude was specified by trimming.

 

I'll do some more tests tonight, with some free flights, and post my findings.

 

Thank you.

 

Itkovian

[PeterP]

Which version are you using?

 

BS2 had a bug on its initial release: http://forums.eagle.ru/showthread.php?t=80992

 

But with version 1.1.1.1 is everything back to normal and trimming with a FFB joystick is working nice again.

Edited February 1, 2012 by PeterP

[Itkovian]

Which version are you using?

 

BS2 had a bug on its initial release: http://forums.eagle.ru/showthread.php?t=80992

 

But with version 1.1.1.1 is everything back to normal and trimming with a FFB joystick is working nice again.

 

I have not patched BS2 at all, didn't even KNOW there were patches... so this must be the problem! That post is exactly the problem I'm getting.

 

I'll install it tonight and post an update. :)

 

Itkovian

[PeterP]

You can rest assured that a update to 1.1.1.1 will cure the problem!

 

A reminder for everyone:

When posting a problem/bug - add info about the version you are using!!! :)

[Itkovian]

You can rest assured that a update to 1.1.1.1 will cure the problem!

 

A reminder for everyone:

When posting a problem/bug - add info about the version you are using!!! :)

 

Looking at the announcements board might have helped... as it is I just looked at this board and saw nothing of a new patch. D'oh. :)

 

That said, the post served its purpose, thank you a lot for the help (mind you, I'll update after I patch and test it out tonight).

 

Love the sim, and a good community indeed. :)

 

Itkovian

[WildBillKelsoe]

Hi there,

 

I was doing some flying last night, the first real flying since BS2 came out (I've spent time re-learning the manual since BS2's release, but the Simming Gods were unkind to me until now), and I've got a question:

 

NOTE: I have a MSFFB2, and this isn't the old trimming loss-of-control routine, never had that issue with my trusty Force Feedback stick *grin*)

 

While I'm flying in route mode and trim the A/C to a new altitude and speed, the moment I release the trimmer the autopilot seems to immediately react by pitching up for a while before settling down (at a significantly lower speed and higher altitude that I trimmed for). Sometimes, in fact, it will start wobbling as it tries to stabilize itself because it pitched up too much and has to correct.

 

So what I end up doing when I release trim is maintaining a slight forward pressure on the stick to counteract the pitching, at which point the route AP settles down and the rest of the route is uneventful. But this will occur whenever I trim with route mode on (though to be honest, I didn't specifically test if this occurs with route mode off, I'll have to check that tonight).

 

Any thoughts on what might be causing this?

 

Thank you.

 

Itkovian

 

 

Just leave it be, control the nose with the collective... If you reset the trim with route or without route mode, she'll nose up. Therefore, before I reset trim/ suspect a nose-up attitude, I lower the collective fully (provided there is no ground underneath me or I lower the collective just to get the VVI to horizontal (middle)..

 

And just so you know, the trim for route mode adds to stock trim ( normal AP channels on -mode)..

 

So for instance you trim the shark to +2 deg forward, and you then engage route mode, then trim it +1 degree forward, your total trim once route is off is +2 + 1 = +3 forward. The key here being nose and route co-ordination.. By collective...

 

And if you re-engage the route mode, it will return to +2 forward, and you'll have to trim her +1 again, only to suffer a + 6 forward trim once route mode is re-disengaged..

Edited February 1, 2012 by WildBillKelsoe

[Itkovian]

Well, I just installed the patch, and the problem is compeltely gone. Did a free flight, and it holds its trim rock steady. It's a pleasure to fly once again. :)

 

Thanks for all the help, the patch definitely did the trick.

 

Itkovian