acknowledged The huey's performance profile is unacceptably inaccurate (documentation provided)

[sniperwolfpk5]

Great work @Tim_Fragmagnet

[BIGNEWY]

Hi all, 

please if you think something is wrong include the DCS track replays showing your tests. 

Please do not use any mods, and use Caucasus terrain if possible for the test tracks. 

thank you

[BIGNEWY]

I have marked this thread as acknowledge as the team are aware and will look to make changes in the future. 

thank you 

[Jester986]

Honestly I only skimmed this, but as a Huey pilot she does feel a little weak to me and the tail rotor authority is a little lacking. But I can’t be bothered to break out the charts and really dig into the weeds. In my opinion she’s close enough and the autorotation performance feels shockingly right. My biggest complaint is that we don’t have a weight and balance and performance planning options. We should have a weight and balance graph showing our load and way to calculate HOGE/HIGE in game. How are we supposed to be able to plan a mission without this? How many troops can I take? How far can I take them? What altitude can I drop them off at? No idea. It would also have the benefit of putting the performance accuracy question to rest. 

Edited February 28, 2023 by Jester986

[Tim_Fragmagnet]

16 minutes ago, Jester986 said:

 and the tail rotor authority is a little lacking.

With the new knowledge of our torque being too high for any specific speed, you may want to look into this thread as well.
 

 

[HILOK]

16 hours ago, Jester986 said:

My biggest complaint is that we don’t have a weight and balance and performance planning options. We should have a weight and balance graph showing our load and way to calculate HOGE/HIGE in game. How are we supposed to be able to plan a mission without this? How many troops can I take? How far can I take them? What altitude can I drop them off at?

very good points. and if the flight model was accurate enough, we could just use graphs from the original OM, which i personally always prefer 

[Ramsay]

On 2/27/2023 at 9:23 PM, Rudel_chw said:

So, we have been flying the DCS Uh-1 for 7 years now, and yet no one had noticed such great performance difference before?

I have not flown a real-life uh-1h, so I have no idea if it is performing as it should or not, but on this forum there have been real life uh pilots and yet this is the first time that I see such a huge difference in performance being pointed out. Seems odd to me.

No, this isn't the first time the Huey's lack of performance has been noticed - there's a long thread from Jan 2018* discussing the problem ...

... and promises from ED it would be looked into.

However ED's priorities shifted and nothing came of it.

* In 2013 when I bought the Huey I noticed issues when trying to use the RL power available hover charts (similar to calculating rotation speeds for fixed wing) but initially put them down to lack of understanding on my part.

Lack of power/engine overheating only became a significant issue in 2018 when EGT engine damage was implemented, by then I had a better grasp of the charts and how to read them, so was one of many who reported the mismatch between DCS and RL performance (note some threads/posts have been deleted/lost perhaps due to rule 1.16). 

Edited March 1, 2023 by Ramsay

[PilotMi8]

14 минут назад, Ramsay сказал:

No, this isn't the first time the Huey's lack of performance has been noticed - there's a long thread from Jan 2018* discussing the problem ...

... and promises from ED it would be looked into.

However ED's priorities shifted and nothing came of it.

* In 2013 when I bought the Huey I noticed issues when trying to use the RL power available hover charts (similar to calculating rotation speeds for fixed wing) but initially put them down to lack of understanding on my part.

Lack of power/engine overheating only became a significant issue in 2018 when EGT engine damage was implemented, by then I had a better grasp of the charts and how to read them, so was one of many who reported it (note some threads/posts have been deleted/lost perhaps due to rule 1.16). 

 

thank you for finding errors, nothing just goes away!))
HUEY engine is in the fixing stage now, and its model update will come out in a while

PS about deleting any messages about Huey - I don’t know ... there were no problems, no instructions were given to delete something from messages about Huey. Maybe the moderators themselves decided and deleted something ..

[Rudel_chw]

23 minutes ago, Ramsay said:

No, this isn't the first time the Huey's lack of performance has been noticed - there's a long thread from Jan 2018* discussing the problem

thanks for pointing it out, will take a read and hopefully ED will agree to improve their engine modeling. 

[BIGNEWY]

29 minutes ago, Ramsay said:

No, this isn't the first time the Huey's lack of performance has been noticed - there's a long thread from Jan 2018* discussing the problem ...

... and promises from ED it would be looked into.

However ED's priorities shifted and nothing came of it.

* In 2013 when I bought the Huey I noticed issues when trying to use the RL power available hover charts (similar to calculating rotation speeds for fixed wing) but initially put them down to lack of understanding on my part.

Lack of power/engine overheating only became a significant issue in 2018 when EGT engine damage was implemented, by then I had a better grasp of the charts and how to read them, so was one of many who reported the mismatch between DCS and RL performance (note some threads/posts have been deleted/lost perhaps due to rule 1.16). 

 

Hi, if you have a problem with moderation you should always PM me or nineline. 

4 minutes ago, Rudel_chw said:

thanks for pointing it out, will take a read and hopefully ED will agree to improve their engine modeling. 

Please read the above post from PilotMi8

 

thank you

[Tim_Fragmagnet]

So, I was asked to provide track files, that seems to no longer be a requirement

However, I had still made them, if you wish for me to provide them, simply ask. However, the flights did allow me to produce more information.

I flew the huey at 6,500lbs, 7,500lbs, 8,500lbs, and 9,500lbs, each at speeds lining up with specific points on the torque performance chart in the manual, these were flown at TRUE airspeed, facilitated by the use of the true airspeed display in the F2 infobar. So there is no error in the data collection due to IAS inaccuracies.

I then compiled the information onto a chart alongside the real huey's torque performance.

here is that chart.

The expected torque values have been corrected by the 2sqft drag factor of the IR suppressor.

 

As you can see, we are underperforming by a fairly significant margin at higher speeds, and the loss in performance forms a very clear trend as you can see by the delta data at the bottom.


However

that is not the full set of data

This is.

 

 

 

Now, you're likely wondering what those extra bits of data are at the top end of the graph.

Those are plots of the real huey with standard blades being pushed past its transmission limit, all the way to the maximum output of the engine, 1340shp.

However you will notice that if you try to line them up with the real composite blade huey data, they don't form a smooth set of data. That is because the composite blades have higher performance than the standard blades due to being lighter.

So, if you spare a little bit of your imagination, just for a moment.

This is what I propose

I didn't really know exactly what to do here, I could have just shifted the standard blade plots to the right until they formed a smooth plot of data, but that would put the huey at somewhere near 160knots at 6500lbs if you push the engine all the way. Instead, I opted for an assumption, while the new blades are higher performance, they're also lighter, meaning drag on the rotor is more of a factor, meaning a higher blade pitch likely produces more torque than a heavier rotor, coming out to what is actually a reduction in max power performance but an improvement in the performance at the transmission limit.
 

 

Now, I'm sure there's some math in the composite blade documents that could let us just compute the real performance of the composite blade huey at that level of power output. However, I do not have the intelligence to do it.
I believe this would be the math.
null








As for where that standard blade huey data comes from.

once again, our friend from the original post

 

On page 95 we have a velocity limits table


As a reminder, the transmission limit is not the absolute limit of the aircraft, it can push harder to achieve max power performance, you are just risking damage to the transmission. All of these speeds are in true airspeed in knots.



As a reminder, that table is for the STANDARD blades, NOT the composite ones. the data shown there is theoretically lower than it would be for the composite blades, however I do not believe that I have found similar data for the composite bladed huey, so we can only guess as far as I know.

Edited March 1, 2023 by Tim_Fragmagnet

[firefox121]

Hello...Hello, sorry....but.....at the end, this is a game, and this is for fun......don't bother if I can fly with two...or twenty troops, just fly and have fun....I am not a real pilot and I don't need this tables......if all is implemented as the original chop, we will have less fun, because , at first, is impossible to feel the g-forces, or the behaviour...., so please enjoy the game...

ED if you take all this and adapt it to the game, please leave a "for more enjoy" option or something like that for all we just fly and fun......

As mandalorian said....this is the way......

 

[SPAS79]

52 minutes ago, firefox121 said:

Hello...Hello, sorry....but.....at the end, this is a game, and this is for fun......don't bother if I can fly with two...or twenty troops, just fly and have fun....I am not a real pilot and I don't need this tables......if all is implemented as the original chop, we will have less fun, because , at first, is impossible to feel the g-forces, or the behaviour...., so please enjoy the game...

ED if you take all this and adapt it to the game, please leave a "for more enjoy" option or something like that for all we just fly and fun......

As mandalorian said....this is the way......

 

At the end of the day if ED implements what Tim is pointing out, IT IS going to be "for more enjoy". Flying the Huey will be the same, you will just have more power to spare, you will be able to fly faster, higher and with heavier loads... 

Nothing else should change. 

[firefox121]

hace 16 horas, SPAS79 dijo:

At the end of the day if ED implements what Tim is pointing out, IT IS going to be "for more enjoy". Flying the Huey will be the same, you will just have more power to spare, you will be able to fly faster, higher and with heavier loads... 

Nothing else should change. 

If it is like you think, perfect for me....I didn't read all the blahblahbl data that mostly is inintelligible for me ( ), If I can have the same funny experience ED has all my consent...

[Lurker]

On 3/2/2023 at 12:45 AM, SPAS79 said:

At the end of the day if ED implements what Tim is pointing out, IT IS going to be "for more enjoy". Flying the Huey will be the same, you will just have more power to spare, you will be able to fly faster, higher and with heavier loads... 

Nothing else should change. 

More importantly the Huey will be more manageable at edge of the envelope conditions, which is where the "more enjoy" is, flying this thing at treetop level and coming in for fast landings is basically the reason I bought the Huey, and while I have been able to manage doing it, it always felt like I was barely able to keep it from falling out of the sky. Some of that is definitely due to pilot error, but it looks like that wasn't the whole story. KUDOS to the OP, hopefully Eagle Dynamics gets this sorted during this decade. 

Edited March 7, 2023 by Lurker

[admiki]

Even if we get more power, nothing will change.

It shakes like a wet dog if you go over 100 knots anyway, we'll load more stuff into it and be power limited again.

We'll have more performance higher up, but tbh, I don't see a lot of high alt flying going on on servers in the first place.

Edited March 7, 2023 by admiki

[Tim_Fragmagnet]

8 hours ago, admiki said:

Even if we get more power, nothing will change.

It shakes like a wet dog if you go over 100 knots anyway, we'll load more stuff into it and be power limited again.

We'll have more performance higher up, but tbh, I don't see a lot of high alt flying going on on servers in the first place.

 

Our performance high up as it is, is already too high. In fact, we GAIN performance as we gain altitude up to about 8000ft density altitude right now, which is not what is supposed to happen.
Anything over 5000ft density altitude sees our huey currently performing over spec.

If it were realistic we would have worse performance higher up than we currently do.

Also saying "we'll load more stuff into it and be power limited again"

Load WHAT into it. We are underperforming by an amount equal to what our useful load should be. Our huey at 6500lbs is currently performing like its at 9500lbs.
So if you load our current huey to 9000lbs, it's basically performing like it's at 12000lbs
Fix the power issue, and it would then correctly perform like it's at 9000lbs, what else are you going to throw into the helicopter that will add another 3000lbs that would cause it to perform like it previously did.
What are you going to load full fuel, all the miniguns, the rocket pods, 2400lbs of troops AND a slingload onto it? You being power limited at that point is YOUR fault.

And it's not "getting more power"

it's "using the correct amount of power"
We are currently using TOO MUCH power, that's the problem. Which INCIDENTALLY, also means we are generating too much torque.

If the power usage gets fixed, we will be generating less torque, which will mean an increase in stability.
If this gets fixed, the huey will be more stable and shake less, because currently, with our overdraw of power and thus overproduction of torque, we have to jam the pedals to the left to combat the torque which causes axial instability from the tail rotor. Lower the torque, lower the required amount of left pedal, lower the axial instability, lessen the shakes, gyrations, and wobbles.

[Lurker]

17 hours ago, admiki said:

Even if we get more power, nothing will change.

 

Seriously? So, less power required, less torque required will change absolutely nothing. Yeah, makes perfect sense 

Edited March 8, 2023 by Lurker

[admiki]

1 hour ago, Lurker said:

Seriously? So, less power required, less torque required will change absolutely nothing. Yeah, makes perfect sense 

 

I meant we will load more stuff and have same performance. It's just how human nature is, if it's there we will use it.

[Lurker]

 

On 3/8/2023 at 10:25 AM, admiki said:

I meant we will load more stuff and have same performance. It's just how human nature is, if it's there we will use it.

How is that not changing things? Once you load it up, you suddenly have a much heavier helicopter. More mass = more inertia. Completely different handling. 

Edited March 10, 2023 by Lurker

[Tim_Fragmagnet]

Here's some interesting data


From

 

 

 

We find info on the gas producer speeds for a huey with the standard blades.

 

Ground Idle/start speed 48-52% on the gas producer gauge.

We can test that in game.

\

 

 

 

57%
Nearly 10% too high, interesting.

 

One would assume the new rotor blades wouldn't increase idle power requirement by that much. 
I'll have to do some digging to try and find out what's going on with that.

Edited March 19, 2023 by Tim_Fragmagnet

[Foka1]

Hello!

I think there is a degree of misunderstanding brewing up here   So I will clarify some things.

First of all most likely post of PilotMi8 was misunderstood, English is not his mother tongue but he tries to improve  

What PilotMi8 indeed said is that UH-1H engine model is indeed being reworked and in testing stage. What he did not mention is that UH-1H engine model was in the workshop for some time already (we are talking at least year). So rephrasing his answer you can read it as "We've already developed new engine model and it is in testing phase currently and should be available in one of the next near updates"

I'm clarifying this mostly to prevent some time wasted in vein, but I'm a bit too late, sorry

Essentially what this thread started from is a good initiative. Only problem is it is done on the currently available old engine model. I would suggest at this point to not waste your time on testing old engine model and save it for the new model when it comes out.

We've gathered problems of old engine model years ago and new model should reflect all the needed tuning. There will be more details about new engine model in the newsletter.

Let's reconvene after new engine model is out and you guys can try it. 

Again sorry we couldn't clarify it sooner and save some of your time.