FM - vertical speed in turns. Neutral pedal v slight input.

I'm finding the turn performance at cruise in the Gazelle still to be a little odd.

It's something that was addressed before in a previous patch but it still seems off. In a constant rate banked turn with neutral pedals and ball centered the helicopter will descend without collective input. With just a tiny amount of pedal in the direction of the turn the helicopter will maintain altitude although the instruments indicate the turn to now be slightly uncoordinated. The amount of pedal input, even very slight, has a dramatic effect on the vsi needle in the turn. It's as though without the slight pedal input the helicopter is sliding laterally rather than turning. Is this a factor of the fenestron tail rotor, the SAS or an issue with the flight model?

Anyone else find it seems a bit off?

I will not fly her until Sunday.

Is this the same in both left and right turns?

Yes. Which makes me think it's a FM issue as lift in the turn increases both when working against and with torque.

Interesting, especially as you are nosing down into the turn.

do you think this is a new update thing as I did not notice it previously.

Also note that seating angle to reading the slip ball can give a slightly incorrect reading to what you think is ball centred.

Just so that I can replicate it on sunday... maybe Saturday :D are you simply banking into... lets say a 45 degree turn and allowing the chopper to turn naturally or are you pulling a touch back?

What is your air speed doing whilst naturally turning and nosing down?

What I'm experiencing isn't new to this update. I've considered a few things that could cause this at my end. I'm not using self centering pedals so perhaps I've been flying uncoordinated and it only becomes obvious in turns or maybe I need to compensate for the loss in the vertical component of lift when banked with more collective.

As an example to try and illustrate what I'm experiencing try a banked turn with neutral pedals without compensating for the bank angle with collective and notice the VSI. Then repeat with a very slight pedal input into the turn and again no collective change. The difference in the VSI should be very noticeable.

This aircraft does not like turns, you give a little force and it bleeds off all airspeed.

Doesn't help the fact that the Gazelle continues to pitch/roll in the direction you give it, despite you returning the stick to center. You end up over rolling and losing a ton altitude.

I wish Polychop would address these issues, as there are a few threads asking the same questions with no reply from them :(

Also still missing basic aerodynamic effects like flap/blowback.

Strange.... ok Sunday was to long to wait!

If I keep all controllers neutral and bank into a very slight turn I loose lift and start dropping (no pull back and no push forward on the cyclic).

If I add a touch of pedal into the turn I loose height real fast but gain speed. To maintain the turn without loss of height collective and pedal work is critical but is liquid and easy to maintain.

What angle are you turning and are you pulling on the cyclic to maintain lift (nose up)?

By the way did the last jetseat update make vibros stronger?

I also note that you have the komodo sim cyclic.... I spent an hour with that bad boy when komodo sim was setting up for an exhibition... flying the squirrel chopper in FSX I think, never did I work so hard.

That cyclic ain't liquid.... it is soaking fu%8£ng wet in the centre zone!... very nice.

are you using the joystick cheat window?

I'm not using the window as I'm in vr. As the Komodo is so smooth perhaps I'm unwittingly pitching the cyclic in the turn. I'll test further to see.

My Jetseat is currently in bits waiting to have the vibe motors fitted to my g-Seat so I can't comment on the gazelle effects. I haven't had time to work on it lately.

I have said this from day one and spent quite some effort via PM explaining why I think the FM very off, the more I look into it, the more off I find it. The last answer I got was they are busy with the mistral and multicrew, and after that is finished they will have a look at the stuff that I have pointed out in quite some detail. The explanation was: "our testpilots did not point these issues out".

Basically in my humble opinion, the gazelle tries to fly like a helicopter but fails. The only input affecting pitch and roll is cyclic, where in a real helicopter any input affects pitch and roll. You pull collective, nose goes up. You press a pedal and you will introduce roll (less than yaw of course, but it will roll!). You gain speed your nose will pitch up. Nothing like that is happening in the gazelle, and I am 100% sure this is not because of the semi-rigid rotorhead, the SAS, the fenestron or the gazelle being different. After all it has two spinning disks that are bound to physics. This is just because it is not modeled. If you wanna slow down you apply aft cyclic and hold attitude by lowering collective accordingly, if you do this in the gazelle it will not stop pitching up with aft cyclic no matter how much you lower collective, actually collective seems to have absolutely no influence on pitch attitude AT ALL, which is plain unrealistic.

Sorry Polychop, I have been pointing this out since the initial release, and I will continue to point this out until you at least acknoledge there is somethign wrong or explain in a reasonable way why my assumptions are wrong (I am always happy to learn). So far all you said is "there is only tweaks necessary to the flightmodel" and "we cannot simulate the rotorhead 1:1" and "our testpilots are very happy, and they flew the real deal thousands of hours".

I have said this from day one and spent quite some effort via PM explaining why I think the FM very off, the more I look into it, the more off I find it. The last answer I got was they are busy with the mistral and multicrew, and after that is finished they will have a look at the stuff that I have pointed out in quite some detail. The explanation was: "our testpilots did not point these issues out".

I know a current EC-135 pilot who bought the Gazelle module 1-2 weeks ago.

Now it is his favourite DCS helicopter.

Maybe the FM isn't 100% perfect but it could be closer to the real thing than you thought.

I know a current EC-135 pilot who bought the Gazelle module 1-2 weeks ago.

Now it is his favourite DCS helicopter.

Maybe the FM isn't 100% perfect but it could be closer to the real thing than you thought.

Do me a favour and ask him if the EC-135 will pitch up if you pull collective in forward flight while keeping cyclic in place.

Ask him when he presses full pedal either direction at about 30 knots if the EC-135 helicopter will roll or if he can keep cyclic in place (apart from the obvious yaw).

Ask him if applies slight aft cyclic at about 80kias and keeps it in that position, if he is able to stop the helicopter from nosing up by lowering collective until the helicopter stops, or if it will keep nosing up until you put cyclic fwd again. Ask him to repeat the same process in the Gazelle and let us know what he thinks.

This reliance on pilots impressions is very dangerous.

Don't believe me... believe the guru of FM of ED

https://forums.eagle.ru/showpost.php?p=2847042&postcount=53

It annoys me a bit to see the appeal at emotions some devs do with this "6 pilots tested our plane and they said we are awesome... and forgot to check if the flaps and gear do something to FM". It makes them confident when they should doubt. You can see confidence oozing out of their posts and that scares me. "Oh is the SAS doing magic!" There is no magic in science.

A problem that is not admitted have almost zero chance to be resolved.

This is dangerous like being confident you can finally ride to the max a motorcycle and crashing in the first turn.

I am an arm chair DCS pilot only. I could fly decently Ka-50 when UH1H came out and it was difficult... it was tuned, tweaked and still needs tweaking but I can fly it now without any stress and feels OK. Mi-8 was easier for me... it was more close to BST home I think, it has more automations and they had a lot of engineers to correct pilots "impressions" (As Yo-Yo said). I can fly Mi-8 good.

But this little bird? Feels the oddest and unnatural of all in DCS. To take off you don't touch cyclic! If you touch it you die. I have a FFB stick and obviously without FFB implemented yet it stays limp out of center. When I take off vertically I need to make sure the stick is 100% centered. No skill no nothing. Stick centered, a bit of rudder as she goes and pull pull pull... It would be a BF like helicopter with more buttons if it wouldn't go haywire on different regimes.

They say is nimble because is light. It also is underpowered I think... It shouldn't try to kill you that easy.

One more thing on pilots. They are not gamers. Remember the story with the Mirage 3 test pilot that after some inconclusive talking with engineers finally in one flight decided to open the airbrakes in supersonic mode? He almost hit the HUD with the face. What a gamer would do do in first 30 seconds of first flight? Go supersonic then drop the gear because he want to land on a cloud! What a "Pilot tested FM" will do? Nothing! No pilot in his right mind would drop the gear in supersonic.

Pilots may know their aircraft well, but not as well as the engineers that designed it ;)

Great post zaelu!

I totally share you're view on the Gazelle feeling of flight i DCS - it's a very "distanced" feeling (you as a pilot are not in "contact" with the flying of this chopper)

No pilot in his right mind would drop the gear in supersonic.

I think, this is the point. When real pilots check the FM they stay in an envelope as they would in a real aircraft – in case of the gazelle: small movements on the controls according to the flight state, learned procedures in given situations, not even attempting to fly a looping or pushing the collective down to recover 20ft AGL after the free fall. In this envelope the FM may be pretty good – now an armchair pilot takes the controls and tries manouvers that would never be flown IRL, the FM feels ›wrong, not like the real thing‹ and no one can say wether it is or it is not as no one knows how the aircraft behaves in the real world when it was flown that way.

Nevertheless I think the FM is not yet fully done in this state of development. Rapid movements on the collective should induce torque and changes in pitch and maybe in roll. I don’t think the SAS-Magic is that quick and that precise to let the aircraft fly as it was on rails – especially when Gyro and AP are turned off ;)

But the gazelle is under heavy developement and I assume/hope the FM will be tweaked further like the other things that will be improved over time :)

So just some history about how things get developed. We pour through lots of manuals to learn everything we can about the aircraft - this includes both flight and service manuals. This helps us determine when a pilot turns on X it's suppose to do Y. There is a lot of that even in a small helicopter like the Gazelle.

Then the FM starts. We take any flight data we can find (and usually we have a lot before we even start) and work to convert that to DCS. DCS itself is a bit different then other simulators, mainly X-plane, in that the FM is programmed into the aircraft. In X-plane, you model the aircraft and engines and the real world determines the FM. In DCS you could have a C-130 with a FM of a Gazelle because that is whats programmed into it. So we program the FM. Now at this point, we need pilots who fly the aircraft to tell us if it feels correct or not. If it doesn't, we have to translate what they tell us into FM code. Not as easy as somewhat would think. We fix, and re-test, and fix, and re-test. Sometimes the pilots are busy and testing takes longer...so you get some gaps between FM tweaks.

Currently we're working on fixing up the multi crew side of things. There are a lot of small things that need to be fixed. Also the FFB needs a bit of work as well and we are working on that already. We're also getting the snipers ready for their version, and working on the BO-105. So a bit busy.

So, yes, we hear you. Keep the issues coming, but if you can please limit it to the bug report section so it can be classified correctly and so we don't have to search half way through thread to find it.

A certain amount of perceived FM issues will be subjective. Real world pilots being placed in front of a 2d monitor with a hotas joystick that has springs and completely different travel to the real thing coupled with no feedback other than what they see on the screen will have a hard time expressing how good or bad the flight model feels. Similarly us sim guys can only offer feedback based on implementations of helicopter flight dynamics from this or other sims.

The key is to identify known helicopter behaviors and see are they implemented. That is not subjective. They either happen as expected or they don't. The Gazelle has several areas where improvements need to be made in this regard. The background of the person raising the issue be that real world or sim flying has no bearing on that. I hope Polychop will revisit the FM issues raised that are repeatable and clearly incorrect.

This aircraft does not like turns, you give a little force and it bleeds off all airspeed.

 

Doesn't help the fact that the Gazelle continues to pitch/roll in the direction you give it, despite you returning the stick to center. You end up over rolling and losing a ton altitude.

 

I wish Polychop would address these issues, as there are a few threads asking the same questions with no reply from them :(

 

Also still missing basic aerodynamic effects like flap/blowback.

I am getting the same problem. When entering a slight bank, it keeps banking until I correct with a violent bank in the opposite direction. I think it is a bug in the flight model. The bank input appears to run away even with the stick centered

I am getting the same problem. When entering a slight bank, it keeps banking until I correct with a violent bank in the opposite direction. I think it is a bug in the flight model. The bank input appears to run away even with the stick centered

Is this not because helicopters are dynamically unstable in roll? Once you enter a turn, a number of small corrections will need to be made with the cyclic to keep attitude constant; you shouldn't need to bank violently in any direction.

Check out this video - constant attitude turns are certainly possible.

Video does not show the control indicator. The Huey, Mi8 and KA50 do not bank creep like this. In forward flight a helicopter is stable, because of the airflow straightening it out. To me it feels like a bug in the code allows the bank input to keep creeping up even if the stick is held in position.

Video does not show the control indicator. The Huey, Mi8 and KA50 do not bank creep like this. In forward flight a helicopter is stable, because of the airflow straightening it out. To me it feels like a bug in the code allows the bank input to keep creeping up even if the stick is held in position.

At what airspeeds/bank angles does this occur for you? And are you using any pedal during the turns? I've just fired up DCS and can only achieve some slight divergence (with hands off the cyclic) during turns to the left at ~150 km/h and ~30 AoB. Turns to the right require me to keep applying in-to-turn cyclic which is the opposite of what's happening to you!

Is this not because helicopters are dynamically unstable in roll? Once you enter a turn, a number of small corrections will need to be made with the cyclic to keep attitude constant; you shouldn't need to bank violently in any direction.

 

Check out this video - constant attitude turns are certainly possible.

 

They are very possible. I've never experienced this issue. You don't centre the stick in a turn to hold a given bank angle. It's not a plane!

This is not what this thread was originally referring too though.

Turns to the right require me to keep applying in-to-turn cyclic which is the opposite of what's happening to you!

turn off SAS, you really get to see what we are talking about.

I'll make a video later along with a bug report.

EDIT: here is video:

I have to hold the angle of roll by holding the sticks position. I see no progressive roll or roll back unless I change my stick position.

Concerning the original post;

I only get side slip and climb if I over pull the turn and loose speed, then when I apply pedal into the turn I increase side slip and the chopper slows faster and gains lift with my stable collective setting.

In a normal turn I can hold attitude, speed and altitude perfectly with a little input from all controllers.