Yet Another Trm Post ! (FD)

[kraszus]

I've given up on DCS so many times, yet keep doggedly coming back to it. I've owned it since release but just cant master Trimming (either patch). Using the rudder would spin the craft out of control; banking for a turn would leave me going in a straight line with the craft at an angle (maybe turning very slowly); etc.

 

But today, I flicked Flight Director on and, although my flying was still all over the place, it was tons better. I could use the rudder (gently) and fly to my chosen point and land!

 

I still haven't even looked at the avionics nor fired a shot - want to fly the thing properly first.

 

Feeling very pleased with myself, but get the feeling this isn't the 'correct' way to fly.

 

Later, when I can do combat missions, will being dependant on FD handicap me in any way?

[Nate--IRL--]

I've given up on DCS so many times, yet keep doggedly coming back to it. I've owned it since release but just cant master Trimming (either patch). Using the rudder would spin the craft out of control; banking for a turn would leave me going in a straight line with the craft at an angle (maybe turning very slowly); etc.

 

But today, I flicked Flight Director on and, although my flying was still all over the place, it was tons better. I could use the rudder (gently) and fly to my chosen point and land!

 

I still haven't even looked at the avionics nor fired a shot - want to fly the thing properly first.

 

Feeling very pleased with myself, but get the feeling this isn't the 'correct' way to fly.

 

Later, when I can do combat missions, will being dependant on FD handicap me in any way?

 

Personally I use FD for most flying and only switch it off on a long waypoint leg or in combat. To me it is the more intuitive way to fly, however using the FD does not go well with flying and fighting.

 

I guess the reason you are having difficulty is down to understanding what the autopilot is trying to achieve. Once you understand what it is for and how it does what it does, it will become intuitive.

 

With the FD off you must trim and trim and trim and....... so on, for every change to your flight regime and the autopilot will attempt to maintain the status you last released the trim button at. With the FD on you must trim for your current flight regime you are in(speed & altitude) however you are free to alter course as you see fit, the autopilot will not interfere.

 

The "correct" way, as I'm often told here, is to never use the FD at all, hold the trim down, manoeuvre to desired attitude and course, and release trim. However my view is that the current limitation of the simulated trim and hardware makes the Autopilot more difficult to use than it would be in the real thing. So I fly it the way I want.

 

Another tip might be to leave the FD off, but temporarily disengage the yaw channel when turning and re-engaging it when you get to the desired heading. Note, this is definitely not the "correct" way to fly, but it works.

 

Nate

Edited February 1, 2010 by Nate--IRL--

[kraszus]

Thx Nate - nice to see another Irishman on the forums :)

 

I meant to mention, in FD mode, I rarely have to trim. Are you saying that in FD mode I only need to trim for Pitch / Altitude changes?

 

Am off work tomorrow so gonna play around on DCS for a few hours to try and get this down :)

[Nate--IRL--]

I find in FD mode you will have to trim as you speed up and slow down, just to maintain a straight and level attitude. With the FD off the autopilot will automatically try to maintain a straight and level flight (if that's what you had when you released the trim) no matter your speed.

 

With the FD on you are free to change your Pitch and attitude. The trim will merely establish a new centre point for the controls.

 

With FD off trim not only establishes a new centre point, but also the autopilot tries to maintain the pitch and attitude and heading when the trim is released.

 

Have a read in the FAQ here -> http://forums.eagle.ru/showpost.php?p=572028&postcount=34

 

Nate

 

Edit- Also, ABSOLUTELY vital to understanding what is going on, is to use the controls indicator. This will let you know if you have trimmed to some crazy centre point by accident (this usually happens to me when trying to hover in windy conditions)

Edited February 1, 2010 by Nate--IRL--

[Mr Pink]

Hey guys just your posts and realised that i didnt have my location set!! updated now, Tipperary!!

 

Anyway just getting to grips lately with the autopilot modes/trim and 4 autopilot channels, havent messed too much with the FD mode yet. i think it would be better to use autopilot then transition to autohover and leaves you avaliable to work sensors/weapons identifying and targetting!!

[EinsteinEP]

Krazus,

 

My $0.02USD: Flying for a while with the FD off is a *great* idea. It's really important to learn how the control system works without the autopilot "help". Eventually, once you master flying with FD, you should try the AP again, to see if it works for you. It may or may not! Personally, I fly with Flight Director off about %99 of the time, but I spent many flight hours with it on, trying to understand how the Trimmer works, etc.

 

Here's a link to some lengthy reads on the subject, if you'd like some reading material, otherwise here's some quick take-away points:

- As airspeed, increases, the Ka-50 NATURALLY banks to the right and yaws to the left. You have to counter this with left cyclic and right rudder to maintain coordinated level flight.

- Trimmer trims your cyclic AND rudder inputs

- Autopilot only has 20% control authority

Edited February 1, 2010 by EinsteinEP

[isoul]

Another Auto-Pilot fighter here! No worries, many of us made the same mistake in the beginning!

 

When you start learning the Shark, in order to understand the helicopter's handling, you should fly with FD on for a while. Since Flight Director disables the Heading Hold and Altitude Hold channels it is nice for trainning purposes because it will let you see how the Shark will respond to your input without having the (frustrating while learning) AutoPilot 20% authority over the input nor the Hold channels trying to maintain flight course and altitude.

 

After familiarizing yourself with controling the Shark you can disengage FD and get use in controlling the Shark with all channels on (and much trimming)! Keep in mind that "Autopilot is your friend", don't fight it, get used to it and it will aid you!

Edited February 1, 2010 by isoul

[hollywoody]

Hi, where is the FD switch located so I can try this?

thanks

[kraszus]

Hi, where is the FD switch located so I can try this?

thanks

 

right hand side...it's just to the right of all the other AP buttons.

[Nate--IRL--]

Hi, where is the FD switch located so I can try this?

thanks

 

Blue button to the right of the 4 Autopilot channel buttons. Pg 2-67 of the manual

 

Nate

[hollywoody]

what is the diffferences between TRIM and TRIMMER and when would you most likely use one over the other and visversa? Thanks

[G3]

i think you will find the terminology is referring to the same thing :thumbup:

[hollywoody]

I do notice from the key mapping list it has both listed? any ideas?

[AlphaOneSix]

"Trimmer" is the actual button on the cyclic.

[Frederf]

I wish the FD was called "Hold Suspend" so it was more clear what is was doing. I also forget if FD suspends the ALT hold too of it's just the 3 axial holds.

 

FD is fine if all you want to do is fly since it allows your talents to translate to good control over the aircraft. However in combat normal AP lowers the task burden related to flying and lets you complete the mission.

[Bushmanni]

Here's how I use the autopilot modes. I mostly fly with the default mode(holds on, no FD) because mostly I fly in straight line or look through the Shkval. Then it's good that the chopper stays on course by itself and doesn't need babysitting.

 

The default mode is also nice when landing or popping sideways behind a building or hill. Trim for hover and when you let go of the stick, the chopper levels automatically. All you need to do after this is push left a little for a while to get yourself going to left. After that you can release the stick and keep going to left. When you want to stop, push right until you are stationary and release stick and you are in hover again. Using this method makes landing very easy and accurate.

 

When I need to maneuver for a while or make rapid or extreme maneuvers or just not fly in a straight line I use FD. The default mode has gotten me out of control pretty much allways when pitch or bank angles go over 60 degrees. So using FD when diving for cover, making break turns, etc. is advisable. Basically I use FD allways when not flying straight or doing precise hover flying. In combat I found myself switching FD on and off many times.

 

Example: I approach the target area at 500m altitude (no radar missile threat) and slow down to about 70-120km/h to search targets from long range and I have FD off. When I get closer, I stop to almost hover and do a more thorough search with "turn to target" mode on. I might see a SAM launch or get LWS alarm and instantly turn FD on and dive while shooting flares. I get to safe altitude and turn FD off again while flying a little farther before turning it on again and using my speed to climb again higher. I turn to target area again, stop to a hover, disengage FD and trim. I turn on "turn to tgt" mode again and do a search to find the guy who tried to kill me, find the guilty one and fire him. I keep this up until vikhr targets are destroyed.

 

There might be some infantry and trucks etc. left so I fly closer. I reduce my speed to about 100km/h and trim, have FD off and heading hold off. I trim so that my chopper flies mostly straight. I arm the gun and start searching forward and to sides with Shkval and eyes. I can turn fast from side to side without fussing with trim and stay on that direction while using HMS to point shkval on target and shoot it with the gun. When I'm finished cleaning, I engage heading hold, engage FD and pick up speed, then disengage FD and trim for home flight.

 

One thing to remember when disengaging FD is that it doesn't set new hold parameters for autopilot. Autopilot will try to turn to the heading and attitude you had before engaging FD so you need to trim the aircraft again after turning FD off.

 

Basic thing to remember is that the default mode is to keep the nose pointing in one certain direction and isn't good for much else. If you need to do some turning around, FD is better for that. You can trim the default mode for some constant turn but that's really useful only if you want to keep circling for a while. Maybe you need to stay put and don't need to hover so you can save fuel by flying circles. When I just change direction, I hold the trimmer button while maneuvering. Stabilizing after maneuver for a good trim takes some time and I rather turn fast and stabilize once rather than stabilize for both turn and straight flight.

 

I personally can't understand reasoning behind doing quick presses of the trimmer button. You can't achieve stable trim that way in one push because you have to counter the AP. You will have to hold it least a while to let AP recenter and aircraft stop swaying after resulting jerk. When AP releases, you have to find a new stick position anyway to keep stable flight. It's just easier and quicker to hold the button while maneuvering and release when you have a new direction established.