Hind - Rotation/Spin on ground

[Nightmare22]

I seem to have got the hang of the hind but one thing eludes me, why do I occasionally start frantically spinning on the ground?. Sometimes this happens after performing a cold start and at the point of increasing the RPM and having had NO input on the control surfaces to this point as the revs come up the aircraft will start to spin to the right, even with the wheel brakes on and brake light illuminated and no AP active. I seem to have had some luck stopping this by using reset trim as part of my startup (despite it already showing centred) but when it happens rudder input does nothing.

 

It also happens when I then land again, I get a satisfying nice gentle landing. Settle back to idle speeds, the aircraft can even be stable for some time on the ground then after a few seconds the spin starts again, stomping the brakes or applying the wheel brakes has zero effect - i've even had a gentle landing, rearmed all fine - gone off to make a drink and I come back to a smashed up helicopter that's spun itself to death  

[scoobie]

Hi, I'm super new to Hind, I've only had a few rides, so I don't if this is a side effect of some RL system operation ("correct as is") or it's a bug.

However... watch the pedals in the cockpit and you'll see what's going on! At some point during start-up from cold & dark, the right pedal (I think it's the right one) starts moving forward on its own, in such funny jerky steps tick-tick-tick-tick... it moves all the way forward and so she starts spinning around.

In order to prevent it you simply need to tap any of your pedals, this automa-tick-tick-tick will stop and pedals (in the cockpit) will miracously recenter.

I suspect that when this phenomen is NOT occurring (sometimes), it is when you (or I) have already tapped or moved the pedals before the tick-tick.

 

(It never happened to me after landing, though, so I don't know.)

 

EDIT: Wait... "rudder input does nothing"... it does cure my Hind. Maybe they are two different cases - yours and mine. Also... since trim reset helps (I never tried that), maybe it has something to do with "rudder trim" option turned on in "Special" menu? I have it on. I'll see if turning it off changes anything.

Edited September 7, 2021 by scoobie

[71st_Mastiff]

1 hour ago, Nightmare22 said:

I seem to have got the hang of the hind but one thing eludes me, why do I occasionally start frantically spinning on the ground?. Sometimes this happens after performing a cold start and at the point of increasing the RPM and having had NO input on the control surfaces to this point as the revs come up the aircraft will start to spin to the right, even with the wheel brakes on and brake light illuminated and no AP active. I seem to have had some luck stopping this by using reset trim as part of my startup (despite it already showing centred) but when it happens rudder input does nothing.

 

It also happens when I then land again, I get a satisfying nice gentle landing. Settle back to idle speeds, the aircraft can even be stable for some time on the ground then after a few seconds the spin starts again, stomping the brakes or applying the wheel brakes has zero effect - i've even had a gentle landing, rearmed all fine - gone off to make a drink and I come back to a smashed up helicopter that's spun itself to death  

could be wind? and angle of attack on the back prop. try setting the crew to "chock the aircraft". also make sure the throttle is in idle.

[admiki]

@scoobiefor you pedal movements, check that synchronise controls in Misc. tab is not active. It seems to be working in reverse of what name implies.

@Nightmare22I guess the spin is to the left? Check that your collective is ALL the way down, especially on spool up. this will input a lot of torque and tailrotor (because of gearbox ratio) does not have power to overcome it.

[Nightmare22]

3 hours ago, admiki said:

@scoobiefor you pedal movements, check that synchronise controls in Misc. tab is not active. It seems to be working in reverse of what name implies.

@Nightmare22I guess the spin is to the left? Check that your collective is ALL the way down, especially on spool up. this will input a lot of torque and tailrotor (because of gearbox ratio) does not have power to overcome it.

I'm pretty certain it's a clockwise rotation, but I could be mis remembering - i'll double check my sync settings and collective next time it happens thank you!

 

4 hours ago, 71st_Mastiff said:

could be wind? and angle of attack on the back prop. try setting the crew to "chock the aircraft". also make sure the throttle is in idle.

Thats an idea thank you I'll give that a go!

 

5 hours ago, scoobie said:

Hi, I'm super new to Hind, I've only had a few rides, so I don't if this is a side effect of some RL system operation ("correct as is") or it's a bug.

However... watch the pedals in the cockpit and you'll see what's going on! At some point during start-up from cold & dark, the right pedal (I think it's the right one) starts moving forward on its own, in such funny jerky steps tick-tick-tick-tick... it moves all the way forward and so she starts spinning around.

In order to prevent it you simply need to tap any of your pedals, this automa-tick-tick-tick will stop and pedals (in the cockpit) will miracously recenter.

I suspect that when this phenomen is NOT occurring (sometimes), it is when you (or I) have already tapped or moved the pedals before the tick-tick.

 

(It never happened to me after landing, though, so I don't know.)

 

EDIT: Wait... "rudder input does nothing"... it does cure my Hind. Maybe they are two different cases - yours and mine. Also... since trim reset helps (I never tried that), maybe it has something to do with "rudder trim" option turned on in "Special" menu? I have it on. I'll see if turning it off changes anything.

 

I'll watch out for this strange behaviour thanks - do let me know if you find a permanent solution to your issues too! 

[scoobie]

Solved for me! Thank you very much, @admiki! I'd never figure it out myself.

Tried a couple of times w/o touching pedals - worked each time. Does it mean it's permanent? - dunno yet, but so far so good.

 

[Radsr30]

This is a helpful video for Yaw issues. I am no way affiliated with this gentleman but his videos are excellent.

 

 

 

[Xtorris]

Another method, is to hit the 'Trimmer - Reset' button prior to increasing the Throttle Collective and/or Flight Collective.

[NWGJulian]

Am 7.9.2021 um 12:09 schrieb admiki:

@scoobiefor you pedal movements, check that synchronise controls in Misc. tab is not active. It seems to be working in reverse of what name implies.

@Nightmare22I guess the spin is to the left? Check that your collective is ALL the way down, especially on spool up. this will input a lot of torque and tailrotor (because of gearbox ratio) does not have power to overcome it.

think i will have to try this too.

 

i have the same problem as the OP, but with the collective!

when i fire up the first engine, i can watch the collective go up all the way from 0 to 100, in small steps.

same happens when i spawn into a hot mi24.

if i do not immediatelly move the collective lever a little bit, it stays on 100%, which leads into a fireball right after the spawn

Edited September 9, 2021 by NWGJulian

[Nealius]

On 9/7/2021 at 6:33 PM, 71st_Mastiff said:

could be wind? and angle of attack on the back prop.

Necroposting because I constantly have issues with the thing spinning uncontrollably once I get to my parking spot and have the parking brake on. Collective all the way down with pitch gauge reading 0. In my case, it consistently happens when there's winds (6-7kts) from the aft-right quadrant. If I park with my nose oriented in the opposite direction, with winds hitting my front-left quadrant, it doesn't spin. But it only happens after I land and park, never on startup despite being oriented in the same way relative to the wind.

 

Edited November 10, 2024 by Nealius

[AeriaGloria]

5 hours ago, Nealius said:

Necroposting because I constantly have issues with the thing spinning uncontrollably once I get to my parking spot and have the parking brake on. Collective all the way down with pitch gauge reading 0. In my case, it consistently happens when there's winds (6-7kts) from the aft-right quadrant. If I park with my nose oriented in the opposite direction, with winds hitting my front-left quadrant, it doesn't spin. But it only happens after I land and park, never on startup despite being oriented in the same way relative to the wind.

 

 

You turn on the wheel brakes? 

[admiki]

7 hours ago, Nealius said:

Necroposting because I constantly have issues with the thing spinning uncontrollably once I get to my parking spot and have the parking brake on. Collective all the way down with pitch gauge reading 0. In my case, it consistently happens when there's winds (6-7kts) from the aft-right quadrant. If I park with my nose oriented in the opposite direction, with winds hitting my front-left quadrant, it doesn't spin. But it only happens after I land and park, never on startup despite being oriented in the same way relative to the wind.

 

 

Might sound as stupid question, but why are you approaching down wind?

Anyway, does it happen when full RPM or when spooling down?

[AeriaGloria]

Brakes are very important. Real pilots are required to lock them with the “parking brake” latch when parking. The nose wheel is free castoring like a shopping cart 

A shopping cart that might way 10 tons. But a shopping cart with a full load of groceries can still be pretty easy to steer, especiallly with all the weight in the back (since the weight in this case is centered right in front of the main wheels) 

[Nealius]

On 11/11/2024 at 7:27 AM, admiki said:

why are you approaching down wind?

I’m not. I’m taxiing to parking. Parking happens to be perpendicular to the wind because that’s how airbases have their parking designed. 

 

On 11/11/2024 at 8:26 AM, AeriaGloria said:

Brakes are very important. Real pilots are required to lock them with the “parking brake” latch when parking

Yes brakes are set. On a second flight I noticed that the aircraft will weathervane itself against the wind (i.e. nose downwind tail upwind) whenever the wind is from the starboard aft quarter despite 0 collective and brakes set. Yaw AP off as well. When parking opposite direction (wind from port forward quarter) this spin does not occur. By “wind” I’m talking 6-7 knots, which should be negligible. 

[admiki]

Can you post a track?

It can get squirely with some wind, but I have never experienced it that bad.

[AeriaGloria]

12 hours ago, Nealius said:

I’m not. I’m taxiing to parking. Parking happens to be perpendicular to the wind because that’s how airbases have their parking designed. 

 

Yes brakes are set. On a second flight I noticed that the aircraft will weathervane itself against the wind (i.e. nose downwind tail upwind) whenever the wind is from the starboard aft quarter despite 0 collective and brakes set. Yaw AP off as well. When parking opposite direction (wind from port forward quarter) this spin does not occur. By “wind” I’m talking 6-7 knots, which should be negligible. 

If the wind is 5 m/s or above, it can VRS the tail rotor when coming from stsrboard. Same if you hover translate right 18 kmh 

[Nealius]

5 hours ago, AeriaGloria said:

it can VRS the tail rotor when coming from stsrboard

....while parked with the brakes set?

Trying to reproduce but can only do so after a full 40+ minute flight. With a hot ground start I can reproduce minor movements but nothing as severe as what's experienced after a longer flight.

Original conditions: Kola, Severomorsk-1 (258ft elev.), real-world weather injected to .miz with the following parameters:
-surface winds 7kts 120
-winds aloft 47kts 300 / 50kts 147
-OAT 3C
-QNH 29.72
-Turbulence 39
-aircraft parked with heading 225

In this track I'm trying to reproduce on Caucausus with the same parameters, however my elevation choices are 150ft or 500ft+ so I went with 460ft at Mozdok with the same weather parameters and aircraft start hot on ground heading 225, 60% fuel and no stores to simulate a lighter post-mission load.

From mission start you can see the nose alread starts to shift left. I taxi around a bit (poorly) and stop at various points to see what happens. The nose can be observed moving/wobbling around slightly. Now after a longer mission and landing, the degree of this movement is much more severe, often causing a 20-degree turn before stopping.

One thing I noticed from looking at the controls indicator, the parking brake / latched brake is indicating almost half strength compared to using the brake axis. 

It's really frustrating to reproduce issues that only occur after longer flights because no one bothers to check a track that's longer than 5 minutes.
 

LastMissionTrack.trk

Edited November 13, 2024 by Nealius

[Gunnar81]

Sounds like it might be a trim issue if you are landing with yaw peddle trim set for forward flight and when you are stationary on the ground it is trimmed to input peddle. I would try resetting trim after you touch down and set park brake as mentioned.

[Raffi75]

@Nealius Can you repeat this with the YAV AP channel disabled? See how it behaves then.