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Gazelle FM bugs?


zerO_crash

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If you go around 200km/h, or faster, the chopper wants to naturally start pitch down, into the ground (stick neutral). I find this weird, as any helicopter that I have ever flown (IRL + in DCS) just seems to require you to pull more pitch forward the faster you go (the helicopter wants to climb by naturally pitching up the faster you go). In Gazelle however, you seem to have to pitch down the faster you go...

 

Also, another thing. When you fly faster, and decide to slow down by tilting the chopper back, I find that depending on the angle of pitch you pull, the chopper can climb (while slowing down) at a collective setting which is close to 0. The only possible explanation I can figure for this is the blades being optimised for lift. Any comments on this Polychop?

 

The translational lift seems to be totally offset, you can fly with really low speed without feeling the need to use much collective. Tried it just recently and I can fly at around 30-40 km/h without translating to hover...? Although I`m not 100% sure about the speed, it was very low, suspiciously low.

 

I have been flying choppers for some 8-9 years, and these mentioned effects are not among things I can correlate my experience with. Now seeing how this is a different airframe, I can accept those characteristics, as long as they are realistic. But it would be nice to know if it`s a bug or not.

 

EDIT: I should mention that for the above, I tried both with SAS and without, and no difference observed.


Edited by zerO_crash

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The few reviews I have found about the Gazelles flight characteristics is that the most outstanding things about the Gazelle are its incredible acceleration and massive climb abilities. They are apparently "Ferrari" superb!

 

The general model is still in Beta remember.


Edited by Rogue Trooper

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zerO Crash,

 

1. never experienced this with the sim Gazelle in other situations than beeing in overspeed conditions. Then it becomes uncontrollable (in a dive) and hits the ground. In fact on my side it is totally as expected...the more speed, the more pitch down to maintain altitude. Some people seem to get some weird behaviour out of this chopper and I have no clue why.

 

2. and 3. I can not comment on this as I never flew the 342 in RL. But I assume, that a reccon/light attack helicopter must be constructed to optimal lift of the three blades (popping up quickly even in hot/high conditions with weight of the HOT for example and hide again...which induces for sure some amount of "stress" on the blades). Climb is specified to 12m/sec in forward flight.

Concering transitional lift: not on my side, and I think we are talking of a situation where the chopper is out of ground effect. I definitely need a fair amount of cyclic (fuel ~40-50%, HOT on/off rails) in slow forward movement. The slower the more - that is what I experience.

 

It would be cool the get a reliable statment on your questions from a former/active 342 pilot here.

[sIGPIC][/sIGPIC]my rig specs: i7-4790K CPU 4.50GHz, 32GB RAM, 64bit WIN10, NVidia GeForce GTX 980 Ti, SSD+

 

A10C, UH-1H, M2C, F5E, Gazelle, KA 50, F18C, DCS 2.5x OB

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to my above posting...just tested again: fuel 55%, 4 HOT, TOW ~4535+ LBS, standard conditions, sealevel

 

To maintain level in slow forward motion (below 60 km/h and slower) I need around 60% of torque at sealevel; hover up to 75%-80% TQ,

 

The faster I go the more the helicopter will climb and vice versa. When I cut collective in fast forward flight without altering my pitch (angle) the 342 will descend not climb. The faster it is (and given that I want to maintain altitude while slowing down the less input on the stick is necessary and the slower I am the more I need. Thats hwo I would expect it to behave.

That does not mean that it is like in real life with the Gaz...thats something a Gaz pilot has to chime in.

 

Another thing is that I would expect the nose come up/down while playing with the collectiv in forward flight....that does not happen above 60 km/h. The gaz just maintains the angle of longitudinal axis and climbs/decends.

 

Just my 2 cts.

 

Have a fine weekend

 

Willy

[sIGPIC][/sIGPIC]my rig specs: i7-4790K CPU 4.50GHz, 32GB RAM, 64bit WIN10, NVidia GeForce GTX 980 Ti, SSD+

 

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To reproduce my first point, I used 4 hots, 70% fuel (full chopper load). Fly at 180 ++ km/h. Then pitch around 5 deg down (as far as I noticed, even 1 degree in pitch below horizon does this). Now put the stick back to neutral. The chopper continues to drop down...

 

The second point, I went with fully loaded chopper again, and tried various degrees of pitch to slow down (increasing pitch up the slower I went), and to my surprise it required barely any collective to keep it level, it was almost too easy to climb.

 

About the translational lift, I will have to test again. If you aren`t getting any issue, then it could have been the wind (always wind in my missions). Will try again without and chime back in on this one.


Edited by zerO_crash

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[quote name=

 

 

EDIT: I should mention that for the above, I tried both with SAS and without, and no difference observed.[/quote]

 

Make sure you turn the gyro off as well. This will remove any influence from the SAS which still has an effect, even with the master off.

 

..


Edited by Holbeach

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..

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If you go around 200km/h, or faster, the chopper wants to naturally start pitch down, into the ground (stick neutral). I find this weird, as any helicopter that I have ever flown (IRL + in DCS) just seems to require you to pull more pitch forward the faster you go (the helicopter wants to climb by naturally pitching up the faster you go). In Gazelle however, you seem to have to pitch down the faster you go...

 

Also, another thing. When you fly faster, and decide to slow down by tilting the chopper back, I find that depending on the angle of pitch you pull, the chopper can climb (while slowing down) at a collective setting which is close to 0. The only possible explanation I can figure for this is the blades being optimised for lift. Any comments on this Polychop?

 

The translational lift seems to be totally offset, you can fly with really low speed without feeling the need to use much collective. Tried it just recently and I can fly at around 30-40 km/h without translating to hover...? Although I`m not 100% sure about the speed, it was very low, suspiciously low.

 

I have been flying choppers for some 8-9 years, and these mentioned effects are not among things I can correlate my experience with. Now seeing how this is a different airframe, I can accept those characteristics, as long as they are realistic. But it would be nice to know if it`s a bug or not.

 

EDIT: I should mention that for the above, I tried both with SAS and without, and no difference observed.

Here is a report of a US evaluation of the Gazelles flight dynamics. It's very informative and should hopefully help Polychop to finish their Gazelle models FM?!

 

https://ntrl.ntis.gov/NTRL/dashboard/searchResults/titleDetail/ADA016921.xhtml

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Please take in consideration that the tested blades are different blades and not optimised for lift like the SA342M blades, which had to be done do to the VIVIANE systems weight.

 

We read a lot on the forums and have read many many documents on the gazelle during the past 3 years, also some documents directly from N.A.S.A.

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Here is a report of a US evaluation of the Gazelles flight dynamics. It's very informative and should hopefully help Polychop to finish their Gazelle models FM?!

 

https://ntrl.ntis.gov/NTRL/dashboard/searchResults/titleDetail/ADA016921.xhtml

 

Thanks for this document, very good read indeed.

Helljumper - M2000C Guru

 

Helljumper's Youtube

https://www.youtube.com/channel/UCK3rTjezLUxPbWHvJJ3W2fA

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Please take in consideration that the tested blades are different blades and not optimised for lift like the SA342M blades, which had to be done do to the VIVIANE systems weight.

 

We read a lot on the forums and have read many many documents on the gazelle during the past 3 years, also some documents directly from N.A.S.A.

So, do you actually mean that changing blades would change the laws of physics regarding the FM??? I am really losing faith in you being able to ever fix this FM... SORRY guys

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Hi Fredo, nobody said that changing the blades would change the laws of physics, or did any of polychop ever wrote something like that ?

No

 

We stated numerous times that we have seen the documents many times. Anything you can come up with as document consider that we might have seen it already or that it was provided to us by many other sources.

 

Maybe we do not fix it in your timescale, true, but in the end it will be fixed. The only thing we as developing team, that is still pulling this off as 2nd job, ask for is patience. Not more and not less, which sounds fair to me, cause during the past year we tryed to be as fair as possible to our customers too, no matter how many complaints or bashing we did read about the SA342M Gazelle and we also brought 3 versions of one helicopter for the price of one, which is also fair in my opinion, although it is not on par with bussniess.

 

I still wish you a wonderful christmas and all the fun in flying the DCS world game

and while you fly your game, we keep working on stuff like new 3D files of helicopters and programming the stuff that needs to be programmed.

 

So, do you actually mean that changing blades would change the laws of physics regarding the FM??? I am really losing faith in you being able to ever fix this FM... SORRY guys

Edited by borchi_2b
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So, do you actually mean that changing blades would change the laws of physics regarding the FM??? I am really losing faith in you being able to ever fix this FM... SORRY guys

 

Dude if you're not able to see by yourself that a doc from 1975 dealing with Gazelle blades won't be valid for the Viviane version as long as blades were changed specially for it, then you perhaps should come back to work before saying stuff like this, you don't look like knowing anything about this helicopter...

 

Nicolas

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Hi Fredo, nobody said that changing the blades would change the laws of physics, or did any of polychop ever wrote something like that ?

No

 

We stated numerous times that we have seen the documents many times. Anything you can come up with as document consider that we might have seen it already or that it was provided to us by many other sources.

 

Maybe we do not fix it in your timescale, true, but in the end it will be fixed. The only thing we as developing team, that is still pulling this off as 2nd job, ask for is patience. Not more and not less, which sounds fair to me, cause during the past year we tryed to be as fair as possible to our customers too, no matter how many complaints or bashing we did read about the SA342M Gazelle and we also brought 3 versions of one helicopter for the price of one, which is also fair in my opinion, although it is not on par with bussniess.

 

I still wish you a wonderful christmas and all the fun in flying the DCS world game

and while you fly your game, we keep working on stuff like new 3D files of helicopters and programming the stuff that needs to be programmed.

 

People forget good things and concentrate on the bad thing. I am very pleased with the way polychop handle the Gaz and how it is modeled. Even with the little FM bugs and oddities it is very pleasant and interesting to fly.

Helljumper - M2000C Guru

 

Helljumper's Youtube

https://www.youtube.com/channel/UCK3rTjezLUxPbWHvJJ3W2fA

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Dude if you're not able to see by yourself that a doc from 1975 dealing with Gazelle blades won't be valid for the Viviane version as long as blades were changed specially for it, then you perhaps should come back to work before saying stuff like this, you don't look like knowing anything about this helicopter...

 

Nicolas

 

It's too typical on this forum, the same happened with the mirage...

Helljumper - M2000C Guru

 

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EDIT: After some more testing, it seems the Gazelle is much affected by wind, esp. from rear. Apparently even the smallest of wind (really talking 1m/s) is enough to push this helicopters rotor ahead and therefore give the impression of it wanting to pitch down all the time. So nevermind this issue, there`s no problem here.

 

Merry Christmas to all ;)

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Dude if you're not able to see by yourself that a doc from 1975 dealing with Gazelle blades won't be valid for the Viviane version as long as blades were changed specially for it, then you perhaps should come back to work before saying stuff like this, you don't look like knowing anything about this helicopter...

 

Nicolas

A documented 1975 test flight can be used as a basis for discussing Gazelle flight behaviour and/or why the SA-342M is different.

 

No one has had an issue with the different performance of a SA-342M to a clean Gazelle, it's easily explained and understood by the increased weight, 'high lift optimised blades', etc.

 

When 'odd' behaviour is seen, it's reported. The last I heard, the FM was being checked with RL pilots and stuff would be fixed if needed.

 

IMHO that's all anyone can reasonably ask for and I don't expect a quick fix because making an accurate flight model is hard (the FM of many modules are still iterating years after 'release').

 

 

Bit of a rant, not in the Christmas spirit:

 

It is disingenuous to suggest that '1975 SA-342 test flight' documentation used in a discussion about pitch, yaw and roll changes in flight is irreverent. It's behaviour is most likely closer than a UH-1H/Bell or AS-350 in a discussion about the flight model but as always it's the feedback from RL Gazelle pilots and SA-342M documents that should be a primary source.

 

Without access to SA-342M documents or RL pilots, we use what's available, be it Gazelle test flights, manuals or personal experience with RL helicopters.

 

When the F-86 was released and the pitch change due to dropping the flaps was queried, IIRC the explanation given at the time was a shift in the centre of gravity, while it still 'felt' off, it seemed a reasoned explanation and only changed when new information came to light.

 

Here I've read 'it's the magic of SAS' there's no pitch/roll/yaw linkage and 'the SA-342M has special blades', so can't be compared to any other helicopter including other 'Gazelles' (i.e. it has special physics) in a discussion about the ease of increasing collective to stop a VRS.

 

If an answer was 'we checked with RL pilots and the 'special' SA-342M high lift blades allow it to power out of a VRS', we might not like the answer but most would accept it.

 

As a closing thought, I'd like to say "Happy Christmas to all" and just give 'PolyChop' time to work their 'magic' on the flight model.

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I still wish you a wonderful christmas and all the fun in flying the DCS world game

and while you fly your game, we keep working on stuff like new 3D files of helicopters and programming the stuff that needs to be programmed.

And the best Holiday wishes and cheer to the whole Polychop team.:xmas:

 

May the season bring you joy and dreams of new helicopters to create!:D

 

Hawkeye

"Yeah, and though I work in the valley of Death, I will fear no Evil. For where there is one, there is always three. I preparest my aircraft to receive the Iron that will be delivered in the presence of my enemies. Thy ALCM and JDAM they comfort me. Power was given unto the aircrew to make peace upon the world by way of the sword. And when the call went out, Behold the "Sword of Stealth". And his name was Death. And Hell followed him. For the day of wrath has come and no mercy shall be given."

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Hi everyone, firstly disclosure up front "I am NOT a pilot" but enjoy throwing the Huey around in DCS it's actually fun. :pilotfly:

 

The Gazelle seems more counter intuitive to fly (see disclosure above) for me because... and please these are not criticisms of the model as such just how it seems to function for me.

 

The model is not consistent between iterations, as in after a cash (which happens often for me :thumbup:) and "Fly Again" the model has somewhat different flight characteristics if not un-flyable at times at least in DCS 2.0x.

 

NGE seems to occur when touching the ground, AKA the skating on ice effect as collective is dropped or the rebound off the ground then drop it effect , not a gradual onset effect. Now this may be a real effect but lack of resolution on DME doesn't help getting a feel for height above ground and for me the view needs to zoomed out a lot and the out of focus effect of near ground as in looking down sux, why wouldn't near ground be in focus?

 

The tendency to "pendulum" especially roll, seems correction is not consistent with reaction but provides positive feedback and worsens the situation, Again that's how the Gazelle seems to respond most times maybe SAS?

 

Okay I am still dialling down the controls on the Gazelle (Huey too) so maybe I'm my own worst enemy but when I do get the chance to throw the Gazelle around it seems like it has no or reduced VRS effect, maybe SAS?? but for me it doesn't feel right.

 

Again for me the Gazelle just doesn't feel consistent to fly and therefore not realistically engaging.

 

Please no flame wars I'm simply learning to fly and happy to learn. :thumbup:


Edited by FragBum
typos

Control is an illusion which usually shatters at the least expected moment.

Gazelle Mini-gun version is endorphins with rotors. See above.

 

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The few reviews I have found about the Gazelles flight characteristics is that the most outstanding things about the Gazelle are its incredible acceleration and massive climb abilities. They are apparently "Ferrari" superb!

 

The general model is still in Beta remember.

 

The thing is when we talk about realism we deal with numbers (most of the time) and comparisons between simulation and real life, not with subjective forms of explanations. What the topic starter has found shows some possible irregularities within the flight model, not that the Gazelle wouldn't be a good climber or have a good acceleration. If you could compare something with real values it would be much better, otherwise it can be misleading.

 

Good day!

When you can't prove something with words, let the maths do the talking.

I have an insatiable passion for helping simulated aircraft fly realistically!

Sincerely, your correct flight model simulation advisor!

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Please take in consideration that the tested blades are different blades and not optimised for lift like the SA342M blades, which had to be done do to the VIVIANE systems weight.

 

We read a lot on the forums and have read many many documents on the gazelle during the past 3 years, also some documents directly from N.A.S.A.

 

Hello,

 

Let me get straight to the subject, and please don't find me offensive, as I'm not, even though pi%##off by what I see when I fly this bird! Did NASA forget to evaluate the gyroscopic and P-factor effects on the rotor in their report? If that's so, it would perfectly explain why the GAZ acts like a space shuttle flying through the vacuum of space. You only induce some pitch/roll accelerations and achieve some maximum angular velocities with the cyclic stick, nothing more, and these accelerations and maximum angular rates don't differ at any flying speeds (IAS or TAS)! A perfect spacecraft. How is this possible? There is NO gyroscopic effect driven by the rotor blades...! Why? Are the blades having 0 (zero) weight? There is NO P-factor (which is purely aerodynamic) simulated either. This explains why the helo keeps a gained pitch and/or roll rate for very long and won't decelerate those gained angular rates as quickly as normally should once the stick is returned to neutral, because the aerodynamic effect being generated on EACH blade is not the correct one. There is just a visual effect of the rotor blades bending under loads during flight, but not a complete aerodynamic effect on each one. The AoA is the angle between the free stream of air and a given airfoil chord (everybody seems to know the definition, but few completely understand it). Remember that a correct aerodynamic effect should take into consideration both the AoA and the beta angles which only together can correctly simulate the effects between the airspeed vector (which seems of concern here) and chord while the airspeed vector may vary quite high (as direction and value, although in a cyclic fashion correlated to the rotor's RPM) as long as there is a relative airspeed higher than zero between the rotor's axis and the free stream of air. The way it is right now demonstrates that not even the AoA alone is being correctly modelled for each blade in flight due to the fact that the airspeed vector's direction that should meet each blade's mean aerodynamic chord depending on rotor rpm, total airspeed relative to the rotor's axis (translational movement) and any angular pitch and/or roll velocities that SHOULD affect the AoA on each blade aren't fully/correctly simulated.

 

Where are these effects which have a huge impact in flight behavior (for helos at least)?

 

I don't have to be a pilot (for quite some years) and aerodynamicist (aerospace engineer) to tell these things! These shuold've already been known. It would've been common sense to just test other DCS (done by Eagle Dynamics not third parties) helicopters to see how in general a helicopter responds in all known situations, because right now, ED are still the best in making authentic simulation of an aircraft's flight behavior (flight model) and it's other systems and so are a benchmark or source in determining if a flight model is accurate enough (modern simulators achieve beyond 95% level of accuracy in FMs) or is still a WIP. The FM is mostly the first thing that you start with (at least that's what I'd do if I were to start my own simulation as I want REALISM and PHYSICS FIRST instead of graphics, electronic systems, etc.) if you want to impress someone and not leave it for last. Don't know how does ED do it, but they do it right with little error. Somewhere in this topic it's said that Polychop had actually talked with RL helo pilots. Don't know if it was just a chat or those pilots actually tested the Gazelle in DCS, but normally they'll all tell that everything that can differ from one helo to another (as well as from one airplane to another) are the values or quantities within the effects, but NOT the effects themselves..., those can't be non-existent and are all governed by the same laws and physical principles.

 

Also, on the other hand, the chopper seems to enter some weird zones of the flight envelope (I don't have it's flight envelope to tell, but I bet that those who have it can look at it and compare it with what the sim does), because in many cases when applying full right and backwards stick for a split moment (to avoid something or just because you want to) and then return to neutral or push full forward and left stick to counter the first inputs the helicopter keeps maintaining a slow rightward roll rate which rarely stops or starts to develop (respond) towards the new stick input, if you haven't already hit the ground. So, in other words if you sharply pull full aft and right stick (no matter how long if beyond 0.5 seconds), the helicopter enters some strange phenomena which keeps it banking right no matter how you'd jerk the stick in order to get out from that situation. You will see this strange effect after the 2nd and further flights from the following posted track:

 

[ATTACH]153910[/ATTACH]

 

People forget good things and concentrate on the bad thing. I am very pleased with the way polychop handle the Gaz and how it is modeled. Even with the little FM bugs and oddities it is very pleasant and interesting to fly.

 

Oh, really? Don't get me wrong..., but if you say that "I am very pleased with the way polychop handle the Gaz and how it is modeled", then that's either because you are ignorant to what's going on or you don't yet understand the laws of physics at the level needed to see what's wrong with this helo, cause right now it has little in common comparable to a real life helo. Do you like flying a spaceship or a rotary winged aircraft flying through air? It still needs work on the FM and I bet the guys will do their best to figure out what's going on (even if it might take to review things back from the beginning, regarding the FM alone of course).

 

Let's not feel offended and rather evaluate what's going on before jumping!

 

 

If there are no hard feelings and we're all looking forward to good results, I wish everyone a Happy Christmas!

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When you can't prove something with words, let the maths do the talking.

I have an insatiable passion for helping simulated aircraft fly realistically!

Sincerely, your correct flight model simulation advisor!

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Hello,

 

Let me get straight to the subject, and please don't find me offensive, as I'm not, even though pi%##off by what I see when I fly this bird! Did NASA forget to evaluate the gyroscopic and P-factor effects on the rotor in their report? If that's so, it would perfectly explain why the GAZ acts like a space shuttle flying through the vacuum of space. You only induce some pitch/roll accelerations and achieve some maximum angular velocities with the cyclic stick, nothing more, and these accelerations and maximum angular rates don't differ at any flying speeds (IAS or TAS)! A perfect spacecraft. How is this possible? There is NO gyroscopic effect driven by the rotor blades...! Why? Are the blades having 0 (zero) weight? There is NO P-factor (which is purely aerodynamic) simulated either. This explains why the helo keeps a gained pitch and/or roll rate for very long and won't decelerate those gained angular rates as quickly as normally should once the stick is returned to neutral, because the aerodynamic effect being generated on EACH blade is not the correct one. There is just a visual effect of the rotor blades bending under loads during flight, but not a complete aerodynamic effect on each one. The AoA is the angle between the free stream of air and a given airfoil chord (everybody seems to know the definition, but few completely understand it). Remember that a correct aerodynamic effect should take into consideration both the AoA and the beta angles which only together can correctly simulate the effects between the airspeed vector (which seems of concern here) and chord while the airspeed vector may vary quite high (as direction and value, although in a cyclic fashion correlated to the rotor's RPM) as long as there is a relative airspeed higher than zero between the rotor's axis and the free stream of air. The way it is right now demonstrates that not even the AoA alone is being correctly modelled for each blade in flight due to the fact that the airspeed vector's direction that should meet each blade's mean aerodynamic chord depending on rotor rpm, total airspeed relative to the rotor's axis (translational movement) and any angular pitch and/or roll velocities that SHOULD affect the AoA on each blade aren't fully/correctly simulated.

 

Where are these effects which have a huge impact in flight behavior (for helos at least)?

 

I don't have to be a pilot (for quite some years) and aerodynamicist (aerospace engineer) to tell these things! These shuold've already been known. It would've been common sense to just test other DCS (done by Eagle Dynamics not third parties) helicopters to see how in general a helicopter responds in all known situations, because right now, ED are still the best in making authentic simulation of an aircraft's flight behavior (flight model) and it's other systems and so are a benchmark or source in determining if a flight model is accurate enough (modern simulators achieve beyond 95% level of accuracy in FMs) or is still a WIP. The FM is mostly the first thing that you start with (at least that's what I'd do if I were to start my own simulation as I want REALISM and PHYSICS FIRST instead of graphics, electronic systems, etc.) if you want to impress someone and not leave it for last. Don't know how does ED do it, but they do it right with little error. Somewhere in this topic it's said that Polychop had actually talked with RL helo pilots. Don't know if it was just a chat or those pilots actually tested the Gazelle in DCS, but normally they'll all tell that everything that can differ from one helo to another (as well as from one airplane to another) are the values or quantities within the effects, but NOT the effects themselves..., those can't be non-existent and are all governed by the same laws and physical principles.

 

Also, on the other hand, the chopper seems to enter some weird zones of the flight envelope (I don't have it's flight envelope to tell, but I bet that those who have it can look at it and compare it with what the sim does), because in many cases when applying full right and backwards stick for a split moment (to avoid something or just because you want to) and then return to neutral or push full forward and left stick to counter the first inputs the helicopter keeps maintaining a slow rightward roll rate which rarely stops or starts to develop (respond) towards the new stick input, if you haven't already hit the ground. So, in other words if you sharply pull full aft and right stick (no matter how long if beyond 0.5 seconds), the helicopter enters some strange phenomena which keeps it banking right no matter how you'd jerk the stick in order to get out from that situation. You will see this strange effect after the 2nd and further flights from the following posted track:

 

[ATTACH]153910[/ATTACH]

 

 

 

Oh, really? Don't get me wrong..., but if you say that "I am very pleased with the way polychop handle the Gaz and how it is modeled", then that's either because you are ignorant to what's going on or you don't yet understand the laws of physics at the level needed to see what's wrong with this helo, cause right now it has little in common comparable to a real life helo. Do you like flying a spaceship or a rotary winged aircraft flying through air? It still needs work on the FM and I bet the guys will do their best to figure out what's going on (even if it might take to review things back from the beginning, regarding the FM alone of course).

 

Let's not feel offended and rather evaluate what's going on before jumping!

 

 

If there are no hard feelings and we're all looking forward to good results, I wish everyone a Happy Christmas!

First:

 

Thank you Maverick, you manage to so eloquently put words on what I’ve been trying to communicate for a long time now!

 

Secondly:

 

Please fill out Polychops bug template (including much from your previous post in it) and post it in the ”Bugs & problems” thread, otherwise I don’t think Polychop will acknowledge.

 

Thirdly:

 

I bought the Gaz six months ago. Quite early I started to question its strange FM. Polychops initial response was that it had been tested by ”RL Gaz pilots” and been found to be ”very close to the real thing”, thereby trying to kill any discussions and whipe any problems under the carpet (my impression).

 

This has gradually changed so that Polychop now acknowledges(!) that the FM needs ”tuning” and that they are awaiting further ”evaluation by RL pilots”…

”Tuning” for me is adjusting parameters and coefficients in the FM to get correct accelerations and rates, and it can probably be tricky and require lots of testing. But letting RL Gaz pilots evaluate this FM any further is wasting their precious time! As You Maverick so well described the FM misses vital parts of helicopter aerodynamics in it, and is now much like manoeuvring a moon-lander in vacuum.

 

t was long since I last coded something but I would guess that we are talking of at least a couple of hundred lines of code needing to be added to the FM, to simulate the missing parts of helicopter aerodynamics? IF JUST Polychop could acknowledge this, instead of talking about ”tuning” and having to wait for mor RL pilot testing - the FM needs to be completed in all parts (still though requiring tuning) before further RL pilot testing will be of real use.

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First:

 

Thank you Maverick, you manage to so eloquently put words on what I’ve been trying to communicate for a long time now!

 

Thank you! I don't want to sound arrogant or bad tempered as some may see me losing it very easy, but this is what I'm an aerospace engineer and pilot for..., for the loving of a realistically made flight model, nothing more!

 

Although the flight model is the most painstakingly hard thing to achieve in order to go past 95% realism as other simulators praise with, but with people which have a good knowledge of flight dynamics and aerodynamics in first hand, only modelling and programming remains an effort.

 

Best wishes!:thumbup:

When you can't prove something with words, let the maths do the talking.

I have an insatiable passion for helping simulated aircraft fly realistically!

Sincerely, your correct flight model simulation advisor!

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It was long since I last coded something but I would guess that we are talking of at least a couple of hundred lines of code needing to be added to the FM, to simulate the missing parts of helicopter aerodynamics? IF JUST Polychop could acknowledge this, instead of talking about ”tuning” and having to wait for mor RL pilot testing - the FM needs to be completed in all parts (still though requiring tuning) before further RL pilot testing will be of real use.

 

I'm on the same track with you mate, but we should only hope that Polychop will take the time to re-look into it. We know they are busy and as they've said they worked 3 years at the helo and that it's their 2nd job doing this, so they can't work at it everyday and most probably needed some time to learn flight dynamics and software programming in order to make this all happen. Nobody gets born with knowledge and learning, working and testing cost time and I personally know this well too, but indeed action should take place though, slow but thorough!

When you can't prove something with words, let the maths do the talking.

I have an insatiable passion for helping simulated aircraft fly realistically!

Sincerely, your correct flight model simulation advisor!

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