DCS Mi-24P feels very twitchy

[Richard Dastardly]

18 hours ago, admiki said:

I am. Still there is up-down oscilation at about 120 kph in level flight. I don't know how it is in real life, but I would expect attack helicopter to be more nimble than transport heli. 

It's an assault helicopter more than an outright attack helicopter - I'm not sure there's any other equivalents to be honest, and as a concept it obviously didn't really work because we ended up with the Mi-28. It's definitely faster than the Hip, at least, and from some very limited time in it seems to change direction a little easer. I suspect the wings do some very odd things at times. What's the rough stall speed of the wings? given they're sitting in the downwash it's probably not an easy question to answer.

Edited August 29, 2021 by Richard Dastardly

[Torun]

I find that the Yaw stab channel is currently unstable, so it's a good thing I run foot pedals. The pitch does indeed slip into a Rocking Horse effect at low speeds, it's even induced by using the trim hat sometimes.

But also, I sometimes get a really wierd phenomenon where placing my cyclic at a very specific fore deflection causes it to snap towards half aft. It only occurs when Pitch stab is on. It never occurs on any other aircraft. In Axis Tune settings, the axis doesn't snap like this either.

[Schlomo1933]

Am 16.8.2021 um 15:38 schrieb Hummingbird:

In addition to this I stumbled upon a peculiar characteristic when attempting to fly sideways, with the heli only wanting to weathervane nose forward when flying sideways to the left, whilst to the right it wants to go tail forward. 

 

 

This!!! Exactly this is my biggest problem with the hind ! 

Edited December 15, 2021 by Schlomo1933

[Lurker]

22 minutes ago, Schlomo1933 said:

This!!! Exactly this is my biggest problem with the hind ! 

 

Not sure, but when I think about it it might actually be correct behavior for the Hind. For the life of me I can't see why the devs would not correct this behavior if it isn't correct behavior. 

Edited December 15, 2021 by Lurker

[admiki]

Need to check more, but it is possible that by flying to the right you are  stalling tailrotor.

[Schlomo1933]

Am 15.12.2021 um 19:30 schrieb admiki:

Need to check more, but it is possible that by flying to the right you are  stalling tailrotor.

that must be an incredible big issue on the real helicopter . If u watch some mi-24 airshow videos u never see such behavior. and the fly much faster sideways as it is possible in DCS.

[IcedVenom]

On 7/2/2021 at 1:06 AM, Lurker said:

Make sure your AP Channels are on. Especially the YAW channel. I don't know why but flying without the yaw channel engaged will change how the helicopter behaves in pitch and make it twitchy. Which is kind of strange. 

 

To me this is currently the most difficult helicopter to fly, although it is much easier to land compared to the Mi8. It is also a bit more twitchy in forward flight during course changes, which is again kind of weird, I would expect it to be more stable than the HIP. I know that PilotMi8 was a HIP pilot, which is why I still believe that the Mi8 has the most accurate flight model of all the choppers in the game. I think that there is something off with how the AP channels work and interact with each other and the helicopter trim in the Hind. But I can't base it off anything but a subjective opinion, and the comparison I keep making with the Mi8. It does make some sense as this is a completely different airframe, but on the other hand I still think that there is something strange going on with the FM, or rather the AP channels\trim. 

I would argue the Mi-8 is much easier to land than the Mi-24 due to the rotor diameter.

[Baldrick33]

59 minutes ago, Schlomo1933 said:

that must be an incredible big issue on the real helicopter . If u watch some mi-24 airshow videos u never see such behavior. and the fly much faster sideways as it is possible in DCS.

Flying with a light load seems much easier. I downloaded an agility test mission which included the Mi-24 and can throw it around the course, fly inside hangars and so on. Fully loaded for a mission and I need a lot more care and can run out of right tail rotor if I mess up!

[AeriaGloria]

1 hour ago, IcedVenom said:

I would argue the Mi-8 is much easier to land than the Mi-24 due to the rotor diameter.

What effect does that have? I’m sure it has an effect but curious exactly what it is. The Mi-8 has larger rotor diameter, but Mi-24 has thicker chord, enough that both helicopters have identical rotor area, and the Mi-24 has a higher speed gearbox to make up for less tip speed

[Schlomo1933]

vor 2 Stunden schrieb Baldrick33:

Flying with a light load seems much easier. I downloaded an agility test mission which included the Mi-24 and can throw it around the course, fly inside hangars and so on. Fully loaded for a mission and I need a lot more care and can run out of right tail rotor if I mess up!

I can do this also , but when u are strafing to the right , u have also to push the right pedal instead the left one. otherwise the hind turn his tail to the wind

[admiki]

2 minutes ago, Schlomo1933 said:

I can do this also , but when u are strafing to the right , u have also to push the right pedal instead the left one. otherwise the hind turn his tail to the wind

Strafing to the right?

[Hummingbird]

9 hours ago, admiki said:

Strafing to the right?

I think he's talking about what I noted earlier:

 

Quote

In addition to this I stumbled upon a peculiar characteristic when attempting to fly sideways, with the heli only wanting to weathervane nose forward when flying sideways to the left, whilst to the right it wants to go tail forward. 

 

[IcedVenom]

22 hours ago, AeriaGloria said:

What effect does that have? I’m sure it has an effect but curious exactly what it is. The Mi-8 has larger rotor diameter, but Mi-24 has thicker chord, enough that both helicopters have identical rotor area, and the Mi-24 has a higher speed gearbox to make up for less tip speed

Well, judging by how Mi-24 is armored and much heavier than Mi-8, that in combination with a smaller diameter you need a higher rotor angle degree to get into a hover of around 10, as opposed to the Mi-8 which is around 8. I'm not an expert in Aeronautics, I'm an Economist, but maybe you're right that they have the same overall surface area, but I remain skeptical. I'm not sure if having a thicker chord is an effective substitute or if the Mi-24 is just heavier or a little bit of both, but I find it  more difficult and requiring much more energy to transfer into a hover from a straight flight than the Mi-8. Mi-24's wings seem to give it more lift in a straight however.

[unknown]

23 hours ago, AeriaGloria said:

What effect does that have? I’m sure it has an effect but curious exactly what it is. The Mi-8 has larger rotor diameter, but Mi-24 has thicker chord, enough that both helicopters have identical rotor area, and the Mi-24 has a higher speed gearbox to make up for less tip speed

Maybe because you "hit" ground effect(~1/2 rotor diameter) earlier in the Mi-8?

[AeriaGloria]

5 hours ago, unknown said:

Maybe because you "hit" ground effect(~1/2 rotor diameter) earlier in the Mi-8?

No I mean I’ve literally read sources that state “Mi-24 has increased blade chord in order to equal same rotor area as Mi-8 despite its longer rotor span.”

I don’t remember the source, it was a while ago, but we can verify this with the in game LUA files.

Mi-8

Rotor diameter: 21.33m

blade chord: .52m

blade area: 4.63m squared

Mi-24

rotor diameter: 17.3m

Blade chord: .58m 

blade area: 3.34m squared

So it’s not the same, I’m sure that source over exaggerates, but with a 18% smaller diameter the chord is increased by 12%, so it more then splits the difference if they had just decreased diameter but not changed chord. It doesn’t equal the Mi-8 blade area so I stand corrected on that, but the difference is smaller then the difference in rotor diameter makes it seem 

Combine with the fact that the gearbox in the Mi-24 spins the rotor 20% faster, the difference in lift becomes even smaller 

Edited February 1, 2022 by AeriaGloria

[admiki]

You can't compare it by blade area. You need to take rotor disc area for comparison.

Mi-8 disc is 356 m2 and Mi-24 disc is 235,1 m2.

[Schlomo1933]

Am 30.1.2022 um 21:56 schrieb admiki:

Strafing to the right?

fast hovering to the right. 

if u hover to the left the chopper will turn his front into the flight direcetion (thats correct). but if u hover to the right, the choppper will turn his tail into flight  direction (absolutly wrong - no helicopter will do this) 

[Lurker]

1 hour ago, Schlomo1933 said:

fast hovering to the right. 

if u hover to the left the chopper will turn his front into the flight direcetion (thats correct). but if u hover to the right, the choppper will turn his tail into flight  direction (absolutly wrong - no helicopter will do this) 

 

Just checking as I haven't flown the Hind in quite a while. Is this still the behavior that the module currently exhibits? 

[Schlomo1933]

vor 5 Minuten schrieb Lurker:

 

Just checking as I haven't flown the Hind in quite a while. Is this still the behavior that the module currently exhibits? 

i think so... havent also flown the hind since 2 patches

 

[AeriaGloria]

12 hours ago, admiki said:

You can't compare it by blade area. You need to take rotor disc area for comparison.

Mi-8 disc is 356 m2 and Mi-24 disc is 235,1 m2.

I’m sure that makes a big difference for things like control leverage, but we’re talking about the lifting area here. How much lifting surface is available. If blade area didn’t matter, everyone would use minuscule or the same blade chord to maximize efficiency with high aspect ratios. Increasing blade chord will absolutely increase the total lift created by the rotor even if it’s effect is slightly differently then a larger span/disk. Chord is one of the main variables in calculating the lift of the wing, and these rotors are wings 

The increased span helos a lot o think in sling loading or cargo lifting, it increases the amount of leverage there is to balance a wide range loads of center of gravities. But I’ll stand by that increasing chord increases lift the same it does on any wing, and that while rotor disk is a good measure of certain things rotor blade area is a good measure of other things, telling actually how much lifting surface there is in the rotor disk and how loaded that area actually is with the weight of the helicopter. Just like how the Hind rotor has 20% higher RPM, if you looked at only rotor disk area I think you would not get the fullest picture of the difference in rotor lift between the two helicopters 

The original statement I responded to was that the Mi-8 was easier to land then Mi-24 becuase of the rotor diameter, and I asked what is the exact effect that has becuase I’ve always been curious other then things live leverage/inertia. I assumed they meant that becuase of larger rotor disk= higher lift, and I wanted to point out that while it may have higher lift the rotor disk area isn’t the only number to look at for that information, as the blades of the Mi-24 themselves have higher chord and RPM

Edited February 1, 2022 by AeriaGloria

[lee1hy]

Turn OFF all APs are better flying this aircraft 

[admiki]

I don't want to hover without pitch and roll AP. I can, but I don't want to

[AeriaGloria]

29 minutes ago, admiki said:

I don't want to hover without pitch and roll AP. I can, but I don't want to

Agree. Some things are smoother, and a lot of things aren’t you can feel the inertia alot more