Flight model?

I haven't spent too much time in this bird but it doesn't appear to me that VRS is modeled and the flight model in general seems more gamelike than sim. I dropped straight down 500 feet and then lightly pulled collective to gently settle to the ground. I thought for a second I was in FSX. Am I the only one?

Again and again the same discussion. This year we will get an update of the FM. Anyway, sim the VRS is complicated because usually the people who can experience it is dead.

NM, I just noticed the other 20 page thread in the root directory. Yikes. Looks like I'm not the only one. Please delete this thread if you want.

If I were mod, but nope, I am just a member like you.

Anyway, sim the VRS is complicated because usually the people who can experience it is dead.

No, thats not true at all. Maybe you ment to be ironic ?

In my basic military training we got teatched to know how it felt by putting the helo in VRS( at safe

altitude, of course). The main idea was to be able to recognize it early and to have done the exit at least once. I done it with two different types, and it really took some tries both times to be able to hot the sweet spot to enter VRS. It isnt easy even when you are aiming for it.

It takes to be very exact in airspeed 0 , or grounds speed = windspeed and direction to get a hit.

We did not stay in VRS that long, but vibrations and a bit unstable/twitchy in pitch and roll and heading and the VSI starting to point downwards.

I also have two collegues that crashed a helo because of VRS, and they still here(we lost another crewmember though, which was very sad :-( .

If we see how some other features or behavior is modelled on some other modules on DCS, I know for sure that some of these are quite overworked in DCS. They wouldnt happen at all, or they wouldnt happen that quick or with that severity. I see there is a risk that the VRS could be overdone in this case. Not maybe how it behaves when in VRS, but how easy it is to accidentally or intentionally enter it.

[Edit]Just remembered this:

When the Gazelle was first released, VRS was a thing, and it was pretty sudden and violent from what I remember. It certainly doesn't exist anymore.

No, thats not true at all. Maybe you ment to be ironic ?

 

In my basic military training we got teatched to know how it felt by putting the helo in VRS( at safe

altitude, of course). The main idea was to be able to recognize it early and to have done the exit at least once. I done it with two different types, and it really took some tries both times to be able to hot the sweet spot to enter VRS. It isnt easy even when you are aiming for it.

It takes to be very exact in airspeed 0 , or grounds speed = windspeed and direction to get a hit.

We did not stay in VRS that long, but vibrations and a bit unstable/twitchy in pitch and roll and heading and the VSI starting to point downwards.

I also have two collegues that crashed a helo because of VRS, and they still here(we lost another crewmember though, which was very sad :-( .

 

If we see how some other features or behavior is modelled on some other modules on DCS, I know for sure that some of these are quite overworked in DCS. They wouldnt happen at all, or they wouldnt happen that quick or with that severity. I see there is a risk that the VRS could be overdone in this case. Not maybe how it behaves when in VRS, but how easy it is to accidentally or intentionally enter it.

 

[Edit]Just remembered this:

 

Thats an interesting comment. Flying DCS I experience it all the time in the Huey/Mi-8 and to a lesser extent the Gaz. Would you say its overmodled in the other helos?

No, thats not true at all. Maybe you ment to be ironic ?

 

In my basic military training we got teatched to know how it felt by putting the helo in VRS( at safe

altitude, of course). The main idea was to be able to recognize it early and to have done the exit at least once. I done it with two different types, and it really took some tries both times to be able to hot the sweet spot to enter VRS. It isnt easy even when you are aiming for it.

It takes to be very exact in airspeed 0 , or grounds speed = windspeed and direction to get a hit.

We did not stay in VRS that long, but vibrations and a bit unstable/twitchy in pitch and roll and heading and the VSI starting to point downwards.

I also have two collegues that crashed a helo because of VRS, and they still here(we lost another crewmember though, which was very sad :-( .

 

If we see how some other features or behavior is modelled on some other modules on DCS, I know for sure that some of these are quite overworked in DCS. They wouldnt happen at all, or they wouldnt happen that quick or with that severity. I see there is a risk that the VRS could be overdone in this case. Not maybe how it behaves when in VRS, but how easy it is to accidentally or intentionally enter it.

 

[Edit]Just remembered this:

 

I just did not want to explain all the way around :music_whistling::music_whistling::music_whistling:

BTW, I find quite useless dicussing a FM that will be changed anytime this year.

Thats an interesting comment. Flying DCS I experience it all the time in the Huey/Mi-8 and to a lesser extent the Gaz. Would you say its overmodled in the other helos?

I have no doubt that Gunnars Driver knows what he is talking about regarding VRS IRL vs DCS.

I've also read an article written by a guy who tries R22 in a different sim. Let's leave it at that. I won't go into details on what sim, but Claude Vuichard was involved with the creation and tuning of the FM. This is a small excerpt from the article:

"What a lot of folks don’t realize is that, although not impossible, VRS doesn’t happen easily. It certainly doesn’t happen as easily as in DCS, for example.

A few pilots I’ve talked to told me that the only situations they entered VRS was because they forced it and, even as they tried it, it was not easy. And it’s not easy with the R22 either."

VRS is a great effect (in a sim!) and a great FM showpiece, but most likely a bit overworked in DCS helicopters.

From what I have read and certainly in game is that it's more common (for me) to get into a situation of settling with power or simply not having enough power to control sink rate as opposed to VRS. But I have also gotten into VRS even in the Gazelle.

Flying Through the Vortex link.

As to FM the last major update was IMHO a huge step in the right direction and the lads are learning a lot from developing their new model so again it can only get better.

I also think some of the bad FM arguments stem from the controller that users have for cyclic input, I've said it before but for me making an actual cyclic for use in DCS had a profound effect on all helicopters and especially the Gazelle.

YMMV :thumbup:

I only have the Huey and I havent flown it that much. I dont have that much time playing around and I mostly follow my gaming friends choise of what to fly( and 50% of what we do is racing games).

The huey had a strange behaviour when I got it, around two years ago where it wouldnt stop descending clise to ground, even in autos where the helo cant build VRS. I think that behavior dissapeared by a update. I wouldnt even call that something close to VRS or settling with power, just a bad flight model. After that update I never encountered VRS so, it might be there but if it is I avoid by flying like I did the other 5K plus hours( except those minutes VRS-traning long time ago. I dont know really.

The flight behaviour of the Huey is very good. There is some parts that clearly need to be fixed to be like the real Huey, but it is not important for me.

I like it, I can fly it with my experience and I dont need to ’learn to fly the model’. I have seen full flight sims that actually flies worse.

For the over-do it parts I ment other issues than VRS, for example engine catching fire due to using a little to much power. That wont happen, ever.

I have no doubt that Gunnars Driver knows what he is talking about regarding VRS IRL vs DCS.

 

I've also read an article written by a guy who tries R22 in a different sim. Let's leave it at that. I won't go into details on what sim, but Claude Vuichard was involved with the creation and tuning of the FM. This is a small excerpt from the article:

 

"What a lot of folks don’t realize is that, although not impossible, VRS doesn’t happen easily. It certainly doesn’t happen as easily as in DCS, for example.

 

A few pilots I’ve talked to told me that the only situations they entered VRS was because they forced it and, even as they tried it, it was not easy. And it’s not easy with the R22 either."

 

 

VRS is a great effect (in a sim!) and a great FM showpiece, but most likely a bit overworked in DCS helicopters.

Well darn... And while I want the "sim" to be challening in some respects (you know like dropping bombs right :music_whistling:) I find landing helos to be the most challenging. Ironically not the Gaz, which might mean its more "right" than the other choppas.

which might mean its more "right" than the other choppas

Or it might mean the exact opposite just as well. Which leaves us... where, exactly?

Well, for the continued development of the flight model I see the risk of trying too much as we have seen examples of.

One example might be LTE/ Loss of tail rotor effectiveness. Not all types are prone to it, and the ones that are in all cases I know of arent really that sensitive. One type that can get into it, where flown at least 10K hrs at my home base during my time and it never happened. If you look at the wind directions relative to aircraft where it is possible to get into it, there have been very many times it could have happened becasue by theory the heli was in the ”risk-of-window”. It never happened during this years, and I never heard of any LTE before I entered either.

When constructing the flight model, if you read discussions here it might render the idea that you enter this every time you are inside that window in DCS, despite maybe the risk is 1 on tousand in real life. The ”risk-of-window that the manufacturer or operator use in training is far wider than the actual window, and also a lot of other factors need to hit right on their target.

If properly modelled, perhaps with a slump generator that allows a ”feature” ( for example LTE) to only happen 1/100 or 1/1000 I guess the DCS community will complain and say ”This flight model is wrong cause it wont get LTE” so it isnt easy.

To get close to IRL you need to know your stuff really well and also need to be able to stand up against the ones that claims to know but really doesnt.

[Edit]I havent seen LTE overdone in any model, just an example of where it might happen.

Anyway, sim the VRS is complicated because usually the people who can experience it is dead.

Really? Just try entering VRS at a reasonably safe altitude and I'm pretty sure you will recover without trouble.

Really? Just try entering VRS at a reasonably safe altitude and I'm pretty sure you will recover without trouble.

From polychop: "fact is, vrs is an effect that there are little data sheets available. if customers think there is huge table with numbers available, sorry, there are not. Even ion a 280 pages manual of a flighttest of a helicopter that i had to read the past 3 month , I have not been able to find any data on VRS wat all. A lot of other information that makes the difference in realistic and not realistic, but no VRS, sorry."

Anyway, my statement is not true (well, its one of the principal causes of helo crashes), I am just tired seeing again and again same discussions. The fact is that a some real pilots said VRS is overrepresented in DCS, I think it was the guy who helped with a knwon sim with an R22.

From polychop: "fact is, vrs is an effect that there are little data sheets available. if customers think there is huge table with numbers available, sorry, there are not. Even ion a 280 pages manual of a flighttest of a helicopter that i had to read the past 3 month , I have not been able to find any data on VRS wat all. A lot of other information that makes the difference in realistic and not realistic, but no VRS, sorry

For some helos there is some info about VRS in the flight manual, but not closely enough data for building a flight model.

For one helo I flew before the manufacturer did not at all admit that it could get into VRS. I think they opened up for this later though.

For VRS you dont need flight test data to make a good enough flight model.

I did get the formula for calculating the critical rare of descend speeds for entering VRS in my work. I have them somewhere. Basically, the rotor downwash sets the frames: the heavier the same helo is the higher descend rate ro reach vrs. The smaller the rotor is, for the same weight, the higher descend rate.

There is descend rates values that describes in percent of the downwash when reaching for example disturbed air that causes movements in pitch, roll and yaw and also when reaching settling with power and VRS. I dont remember the details so I wont trow any number from memory. I think I can find the data, anyhow.

For some helos there is some info about VRS in the flight manual, but not closely enough data for building a flight model.

For one helo I flew before the manufacturer did not at all admit that it could get into VRS. I think they opened up for this later though.

 

For VRS you dont need flight test data to make a good enough flight model.

I did get the formula for calculating the critical rare of descend speeds for entering VRS in my work. I have them somewhere. Basically, the rotor downwash sets the frames: the heavier the same helo is the higher descend rate ro reach vrs. The smaller the rotor is, for the same weight, the higher descend rate.

There is descend rates values that describes in percent of the downwash when reaching for example disturbed air that causes movements in pitch, roll and yaw and also when reaching settling with power and VRS. I dont remember the details so I wont trow any number from memory. I think I can find the data, anyhow.

If you find them, can you send me or post them here?, I will send them to the PolyChop guys.

If you find them, can you send me or post them here?, I will send them to the PolyChop guys.

Yup!