Something wrong with flight dynamics.

Hi guys,

Just bought your module tonight.

In all honesty I must say you did an amazing job capturing the soul of this helicopter.

Except, I don't feel her!

Just to let you know my background, I'm a RL helicopter pilot working for civil market, the TR I flew are AS350, AS365, R22 and R44, with a couple hundred hours scattered on those types, most of my flight time is in the Dauphin and 350 in FF nowdays.

Please have in mind I never flew in a Gazelle, but I'm supposing that it has flight characteristics from both the 350 (though the Gazelle must be more rigid like the rotor of an Alouette III) and the fenestron from 365, although much smaller in the Gazelle.

I am also taking into account all the hardware problems associated with the desktop PC, this means, the lack of precision and the lack of sensations.

What I meant by not feeling her, is that I don't feel I am flying a helicopter. Something I felt with Huey, Mi-8 and Ka-50. The responses from the helicopter are not those that I would except in real life (albeit all the differences between types, just talking about non artificially stabilized flight), specially in turns, it feels like it doesn't have a vertical stabilizer. I know that the Gazelle one is small, and probably, has something to do with that, comparing it to the size of the vertical structure of the 365, that is massive, but I really feels like it lacks the feeling of flying. Also when using stabilization, it's like the SAS is fighting with me and not helping me at all flying the aircraft.

For sure, when I fly the Dauphin without SAS (CPL) on the aircraft is more responsive to inputs by the pilot, but it's not like fully mad! :P When in coupled mode, the aircraft is really smooth and stabilized, and in the Dauphin you use the beep trim or trim release to get rid of the forces, but its really smooth. In the 350, the aircraft its really more nervous, the inputs by the pilot feels more immediate, also it's almost half the mass of the Dauphin. The Gazelle, I suppose to feel like the 350 without SAS on, but with it on, more like the Dauphin.

I didn't tried any advance maneuver, such as auto-rotation or any other emergency.

I don't want you guys to this that this is bad criticism, it is not. I'm just hoping you guys can make it work better, or feel better.

I will try it with curves, to see if it feels better, but I am almost sure that is doesn't, because I never used curves for the Huey, and it is a non SAS bird, direct hydraulic control.

Just my thoughts, don't know what others think and I am really curious to ear about real Gazelle pilots and what they think of it.

Kind regards and continue the great work.

Be also aware that I am using a force feedback joystick. Just set it up externally to have centering force.

I have to agree with you Focha.

I feel like I am fighting the SAS when making a turn, it is very hard to hold a constant bank angle without it wanting to roll back to wings level. It takes quite a lot of bank to get it to start turning.

Its a great piece of work. Great potential.

CH Figherstick, Y axis 40.

RW Fixed Wing Pilot

Focha, I know what you mean.

What I felt when doing turns is, you roll into the turn, but when you center the stick to stop the roll (to maintain constant attitude to complete the turn), you can't just center the stick. You have to hold just a slight amount of aileron roll to hold it in the turn. If you go back to center, the Gazelle will roll back to level. My first thought was, "am I fighting some kind of auto pilot assist?", and I haven't learned enough about the Gazelle to know one way or the other. But when I realized that I needed to maintain a little aileron roll to maintain a turn, it made all the difference, and I was able to fly the Gazelle just fine.

This effect has another result, which is part of why I think many people are complaining about the sensitivity of the cyclic. People feel they must pull a lot of cyclic to initiate a turn, but then all of a sudden, the helicopter is banked too much because suddenly it responds very quickly. So they over react and pull back, and sit there flipping left and right because of this effect where if you center your stick, the Gazelle goes back to wings level. The trick seems to be to initiate a turn with minimal stick push, and be patient a moment for it to respond. Then when you have reached the desired attitude for the turn, pull the stick back some, but not all the way, in order to maintain the attitude, and it now it flies predictably. You have to be patient, and use small inputs.

Realistic or not, I can't comment, but this is the required technique to fly the DCS Gazelle.

Regards,

Michael

FOCHA

Bump +1

I have been flying simulators since the 1980's. I have always been fortunate to be able to afford the latest greatest for home use. I have a few hours stick time in a CH53E. Granted it has nothing similar to the gazelle except the names of the controls but wow what a difference. If the real Gazelle requires this much workload from the pilot just to lift off straight to a 5 foot hover and hold it there well... I was born at night but not last night. In real life I worked on, repaired and rigged helicopter flight controls and engine controls for 20 years, if I had ever rigged the flight control system to respond the way this is responding I would have been fired and banned from working on aircraft forever. lol

+1 as well!

I've already opened a thread (cyclic response question) with a similar topic. I noticed that whatever situation I am in, I never move the cyclic more than a millimeter or two. Complete lack of blowback. Kind of feels like in an RC-Helicopter with a broken tail-gyro. :huh:

I do understand the chopper is beta!

I do not understand the lack of communication from Polychop. Everybody thinks the AFM is final and is applauding on how good it is, but I hate to say it is simply very far from finished.

Again, I do understand it is beta and it is no complaint about the current FM status, but please improve your communication Polychop!! (RAZBAM has set the bar in terms of communication with the M2000)

+1 Focha I've a little experience in real copters too and I don't feel the gazelle.

i was on the fence of buying the gazelle, but after reading this and several other threads and user-reviews i will wait and observe how this is gonna be handled and adressed by polychop.

the model looks excellent, overall features, sound, texture, etc is all top notch, but the flight model is kinda the most important thing for a simulator and should always strife to be as realistic as possible (even if that means harder to control, more complicated, less powerful, not competitive in PvP environments, etc).

i really wish there was some kind of demo mode available for DCS modules, something like the aircraft with only extreme low res or crazy colored textures, placeholder sounds, limited flight time, but full flight model, systems. try before buy style.

+1

i was on the fence of buying the gazelle, but after reading this and several other threads and user-reviews i will wait and observe how this is gonna be handled and adressed by polychop.

 

the model looks excellent, overall features, sound, texture, etc is all top notch, but the flight model is kinda the most important thing for a simulator and should always strife to be as realistic as possible (even if that means harder to control, more complicated, less powerful, not competitive in PvP environments, etc).

 

i really wish there was some kind of demo mode available for DCS modules, something like the aircraft with only extreme low res or crazy colored textures, placeholder sounds, limited flight time, but full flight model, systems. try before buy style.

I think you are save to still buy early access. I have no doubt in Polychop getting it as realistic as possible in the future, and buying it now will only support them. Even though I'm very confused about the current flight model, I do not regret the purchase!

Well, i do not agree with you guys. Is it different?, yes. Is it realistic? I cant tell. We know it has been tested by real Gazelle pilots.

I find it rally easy once you change your chip.... I am using very little curves only in rudder pedals. I am really happy. For me it was an another inpulsive purchasing. But i am loving it.

So wanted to response with a couple quick things.

First, make sure any bug/issues are reported in the Bug Report thread that is a sticky. I spent quite a couple hours last night cataloging all the reports bugs from there along with the requests so we can analyze them, replicate them, and correct them. Just makes it easy to have things there, otherwise I might miss an issue like this since I have tons of threads to reply to.

Second, is about the flight model. You bring up a valid concern. So in order to get the correct answer for this, I need to contact our primary coder who created the flight model. Along with him, we also have several real world Gazelle pilots who, along with flying the SA-342M, are currently deployed in various military forces. Some of them are easier to reach then others. But they were a great resource for us for getting this far, and we'll defer to them for any possible modifications to the FM.

So while I'd love to give you an answer now, I'd rather give you a correct answer and it takes time to get that. So know were working on it.

There is something wrong with the FM but unfortunately the community on these forums is apt to saying essentially "You suck, practice more"

As of right now the best way to get the Gazelle under control is via heavy saturation changes to spread out the response over a longer throw instead of the mm sensitivity there is now. I touched on this in a response to Roie the other day and it can be seen in his video. He is able to throw his stick around heavily which implies major saturation and/or curve changes.

http://forums.eagle.ru/showpost.php?p=2762487&postcount=65

Massive saturation and curve changes are a bandaid fix to a larger problem. I'm sure Polychop can get it sorted out over time, just buyer beware at the moment.

Well, I am not a real helicopter pilot, minus a few hours in an R22.

I am an avid helicopter flight simmer though, using a set of full-sized controls and flown pretty much every helicopter on every sim.

I don't know if it's realistic but in my opinion, for what its worth, its just not fun to fly. Not, I feel because it is sensitive (I was hoping for that).

I fly the Gazelle with an X55 and i don't use curves or saturation changes. There isn't even a need for pedals. The twist axis works fine.

Maybe there is a truth to the whole learn to fly thing?

Just give it a chance and try it for more than a day?

So wanted to response with a couple quick things.

 

First, make sure any bug/issues are reported in the Bug Report thread that is a sticky. I spent quite a couple hours last night cataloging all the reports bugs from there along with the requests so we can analyze them, replicate them, and correct them. Just makes it easy to have things there, otherwise I might miss an issue like this since I have tons of threads to reply to.

 

Second, is about the flight model. You bring up a valid concern. So in order to get the correct answer for this, I need to contact our primary coder who created the flight model. Along with him, we also have several real world Gazelle pilots who, along with flying the SA-342M, are currently deployed in various military forces. Some of them are easier to reach then others. But they were a great resource for us for getting this far, and we'll defer to them for any possible modifications to the FM.

 

So while I'd love to give you an answer now, I'd rather give you a correct answer and it takes time to get that. So know were working on it.

Thank you very much Roie! You guys have all my trust and patience.

Maybe there is a truth to the whole learn to fly thing?

try this: fly ~150kph forward level flight. slowly drop the collective and watch your attitude. As far as my knowledge goes, every helicopter will nose down (even a cessna 172 will if you cut power). The current Gazelle wont.

You can practice as much as you want, it will not change anything on this behaviour.

once again the disclaimer:

I have not flown the gazelle IRL, if this is something it really does i will apologize, I just currently have no reason to believe it does. My understanding of SAS is that it dampens these effects without completely removing them, but even If I switch off SAS i do not see any change. I do reserve the right to be wrong.

Love it, fly it, land it, do it again.

Focha +1!!!

I just don't get why the helo tumbles violently into the opposite direction after giving a cyclic stick input. You move the stick briefly forward and right while in forward level flight, upon moving it back to center the helo behaves as if you would have given an even bigger impulse aft left now and even assuming a nose-up attitude. This is not how it is supposed to be.

Does anybody have found a way to take off without the Gazelle sliding forward for some meters? Not possible. The amount of aft cyclic necessary to stop this tendency actually endangers the tail boom to touch the ground.

Even small pedal inputs frequently induce intense pendulum yaw movement. At the same time, and as already mentioned, applying stick to roll into turns feels as if you would fight against some invisible dragging surface, pulling you back all the time. Maybe that is the reason why I lose half of my airspeed easily in a glimpse when trying to do some agile turns.

Also it feels so weird to apply just enough collective to get airborne and maintaining the collective setting then catapults the helo 10 meters and beyond upwards, just to have it fall back onto the hard ground seconds later. This is not the way it works. It is pretty realistic to have to adjust collective every few moments to keep a specific height while taxiing. But here those adjustments mostly enjoy a range between 55 and up to 70 % on the torquemeter. This range is remarkably huge, only for keeping the helo in its height. In real life, required collective for leaving the ground will at least carry you safely in or just sitting on that cushion. Not so here.

When commencing taxiing, we will of course lose a bit lift vector to gain some slow speed, so a minor increase of collective is obligatory. But certainly not a constant pendulum between 55 and 70 % torque...

Also it feels so weird to apply just enough collective to get airborne and maintaining the collective setting then catapults the helo 10 meters and beyond upwards, just to have it fall back onto the hard ground seconds later. This is not the way it works. It is pretty realistic to have to adjust collective every few moments to keep a specific height while taxiing. But here those adjustments mostly enjoy a range between 55 and up to 70 % on the torquemeter. This range is remarkably huge, only for keeping the helo in its height. In real life, required collective for leaving the ground will at least carry you safely in or just sitting on that cushion. Not so here.

When commencing taxiing, we will of course lose a bit lift vector to gain some slow speed, so a minor increase of collective is obligatory. But certainly not a constant pendulum between 55 and 70 % torque...

I want to agree here. I noticed it especially during lowering the collective. It seems as when you lower the collective just a little bit it starts to descend at a shallow rate, then you lower it just a very little momentum more and suddenly you pretty much tumble towards the ground. That especially happens to me when I'm in a hover and try to descend just a little bit. I know about vortex ring stall, but i can't believe that just a tiny movement of the collective triggers such a "fatal" reaction.

i was on the fence of buying the gazelle, but after reading this and several other threads and user-reviews i will wait and observe how this is gonna be handled and adressed by polychop.

 

the model looks excellent, overall features, sound, texture, etc is all top notch, but the flight model is kinda the most important thing for a simulator and should always strife to be as realistic as possible (even if that means harder to control, more complicated, less powerful, not competitive in PvP environments, etc).

 

i really wish there was some kind of demo mode available for DCS modules, something like the aircraft with only extreme low res or crazy colored textures, placeholder sounds, limited flight time, but full flight model, systems. try before buy style.

There is a demo. You get the whole DCS World for free and then the Su-25T and the P-51 trainer, again for free. That is more than enough for one to decide whether this simulation is worth the money. What more could one ask for?

Guys, please don't go OT.

No one is talking about "buying VS not buying" (I bought it and just started thus thread to make the module even better) or any other subject but flight dynamics.

If you guys don't mind, before giving your opinion I would like to know what are your background (eg. Real life experience, either flight or commercial simulators, etc) and in what you based your opinion on this matter.

So far people have done it, but a lot of people just came here and said simple, non objective senteces that just don't make any sense to me.

As I said, for me, it is not behaving like I would expect from a real helicopter flight, based on my real life experienced and the other modules.

Regards.

Sent from Tapatalk via Samsung Alpha.

So wanted to response with a couple quick things.

 

First, make sure any bug/issues are reported in the Bug Report thread that is a sticky. I spent quite a couple hours last night cataloging all the reports bugs from there along with the requests so we can analyze them, replicate them, and correct them. Just makes it easy to have things there, otherwise I might miss an issue like this since I have tons of threads to reply to.

 

Second, is about the flight model. You bring up a valid concern. So in order to get the correct answer for this, I need to contact our primary coder who created the flight model. Along with him, we also have several real world Gazelle pilots who, along with flying the SA-342M, are currently deployed in various military forces. Some of them are easier to reach then others. But they were a great resource for us for getting this far, and we'll defer to them for any possible modifications to the FM.

 

So while I'd love to give you an answer now, I'd rather give you a correct answer and it takes time to get that. So know were working on it.

Hi,

First of all, sorry if this was placed in the wrong part on the Polychop's forum section.

Second, it is good to know you are working with a lot of RL Gazelle pilots, and that makes all the difference.

No worries about the answer to my question. This was just to talk about the FM, giving you my real life experience, based on other helicopters, not in the Gazelle. That was why I didn't put it in the Bug section, because it might only be a problem based on my own experience in helicopters and nothing more.

Thank you for your reply and I surely know you will look for it, and if it is like this, then it's because someone with a lot more experience then me, told you so.

Kind regards and continue the great work.

and in what you based your opinion on this matter

No opinion so far since I only have the beta (v1.5) at the moment, but I've seen comments by alleged RL helo pilots who think the FM is actually very good for a light and agile turbine chopper. Make of that what you will, but I'll just mention it here regardless ;) Anyway, going to test next Friday if/when the patch for v1.5 comes out...