Death Spin

[eoh]

Hi,

 

just yesterday something strange happened.

 

During an epic mission (I've been ~2hrs continuously in the air) I got a message from a teammate saying we changed our attack plan and were heading for another waypoint.

 

Naturally I tried to do a turn, moved the cyclic and collective in order to head towards our new target. If I remember correctly (sorry, I have no track of this mission -- can I even create tracks of MP mission? if yes, where is that button?) I was initially moving ~150 kph (no guarantees) and the chopper 'felt' a bit like doing a powerslide while entering the turn.

 

Then, suddenly, the whole helicopter started to spin around like hell, as if an imaginary tail rotor had been broken, with about 2 rounds per second. Also, if I remember that correctly I got the feeling the chopper was swinging sideways.

 

No matter what I did, I was unable to recover. I pressed the pedals, they had no effect. I tried to play with the collective, I think it only made it worse. 10 seconds later I was a smoking hole in the ground.

 

So my questions are:

 

1) What is this phenomenon? I am pretty sure that no blades burst or smashed or did something else, at least I heard nothing and it felt different.

 

2) How can I avoid it?

 

3) How can I recover from it? My first thought was "oh shit, vortex suck", so I tried to push the collective in order to gain forward speed, the chopper however didn't seem to respond.

 

 

If anyone could bring some light in this issue I'd be very grateful. Also sorry if this topic has already been addressed elsewhere, but I didn't find something when searching for spinning.

 

Thanks

Ralf

Edited August 27, 2009 by eoh

[ZaltysZ]

Sounds like your tail was blown off. :) Are you sure you were not hit by MANPAD? Anyway, multiplayer tracks are auto saved to temp folder, so look there.

[eoh]

I am pretty sure I have not heard any impact or explosion sound (like I usually do when eating SAMs and others) before that, I was, however, flying over contested territory.

[ZaltysZ]

Watch the track. ..\Ka-50\Temp\...

[26-J39]

Did it happen after you trimmed? There's been some threads about some issues with the new trim locking out the controls.. Might be this? had any issues with trim after 1.0.1 ?

[eoh]

In 1.0.0 I almost never used trimming because of frequent blade crashes. From 1.0.1 I started using it frequently and the only thing I noticed was that the controls lock up unless you move paddels and cyclick back to the 0-position.

 

However, I think I was flying trimmed in that situation, but 5 seconds before the incident I was able to steer perfectly (well, sort of *g*).

[26-J39]

**Trim shouldn't ever cause a blade clash unless your trimming the BS in a wild maneuver. ( remember there is no difference between holding the stick forward for forward flight and trimming for forward flight.. )

 

Still sounds to me like your trim locked out your controls.. might pay to do some experimenting in mission editor to see if you can replicate the problem?

Edited August 27, 2009 by 26-J39

[eoh]

In 1.0.0 trimming added its own force to your cyclic force if you weren't quick enough to release the stick. At ~250kph this quite often resulted in the blades meeting each other ...

 

And regarding trimming in last night's flight: I really doubt that my controls were locked, because I still had *some* authority, just not enough anymore to change anything.

[DarkWanderer]

Looks like rotor failure due to MANPAD hit.

[26-J39]

Hmmm... not sure bud.. :cry: I've never experienced an "out of control spin" in the KA50 unless you bust the blades on one of the rotor heads.

[DarkWanderer]

I've never experienced an "out of control spin" in the KA50 unless you bust the blades on one of the rotor heads.

I've not flown it much, but once after a hit i've got "freed" of all the blades except two on upper rotor. The symptoms looked quite similar.

Was the camera shaking?..

[eoh]

No, thats what brings me to the idea it was no hit. The screen was not shaking. Just spinning and slinging.

 

My personal theory is

 

1) "Caught Spinning Inside a Vortex Ring" (I don't know if that's technically possible, but given the symptoms it is most believable to me)

 

other theories so far are

 

2) Enemy fire (I have not heard anything like an explosion and I was low between hills, I therefore rather doubt that)

 

3) Blade smashing (I had no shaking of the screen and I was rather slow, ~150).

 

Tomorrow I should have access to the PC again, so I see if I find the replay. Until then, if anyone knows something about spinning and vortex rings I would be eager to hear about that.

[nemises]

Accidentally full trimming your rudders...

...trust me, it hapens a lot!...(well, lo...to me anyway)...

Make sure you have your ctrl-enter screen up to be able to tell where you have trimmed rudders too

[L4key]

Accidentally full trimming your rudders...

...trust me, it hapens a lot!...(well, lo...to me anyway)...

Make sure you have your ctrl-enter screen up to be able to tell where you have trimmed rudders too

 

Arf - I do that! It takes me another five minutes to get it from spinning one way or the other. Embarrassing! ctrl-enter screen would help - cheers!

[sinelnic]

The screen was not shaking. Just spinning and slinging.

 

Is it possible that your three AP channels got turned off? (or you got a malfunction on them, becasue of enemy fire or other reason) This is not Flight Director, this is flying without damping.

 

When your AP channels are off the heli starts to spin and sling, conceded not with the intensity you mention, but maybe you can try a test flight doing the same maneuver with the AP channels off, if all other theories fail.

[159th_Viper]

nemises is correct :thumbup:

 

Once you get into your 'Have to Have to Have to Oh Please Have to Catch my own tail' Spin, apply Full Rudder in the opposite direction to the spin. Keep it there amd you'll arrest the Spin. Once you slow down trim for level flight and you'll be good to go!

[eoh]

omg omg omg omg ... the replay is messed up :cry:

 

I arrived earlier at home than expected and tried to watch it. The first few minutes however still match what I really did, but at some time I (yesterday) took a short flight over the sea while in the replay I never returned. In the replay I can see me aiming at the flat water, shooting missiles in it and finally crashing and drowning ...

 

This is not how it ended ... :mad:

[ZaltysZ]

Maybe a gremlin is trying to hide evidence. :D

 

P.S: try to ask the track from other players while gremlin still haven't gotten to them.

Edited August 27, 2009 by ZaltysZ

[eoh]

Regarding the other issues you raised :

 

1) AP turned off: I've also encountered this a number of times but with all off the chopper rather feels like balancing an elephant, still flyable, but nasty.

 

2) Trying to apply full rudder: I tried that, too. I don't want to say I applied it correctly or long enough, but, well, I tried ...

 

 

Have you ever watched Top Gun, where Goose dies because they enter a spin and don't manage to recover?

 

It felt exactly like that.

 

I am not saying that it really was a spin, or that it would be technically possible, I only state that no other reason of crash I encountered during my last half year of playing has even been close to being similar, which is why I initially started this thread.

 

I also really appreciate that you are trying to help me, but I feel a bit sad that most people suggest those every-day-reasons for this crash, whereas I tried to point out that I have had no evidence of such an ordinary occurrence, but in fact it really felt like a combination of vortex ring + spin.

 

Maybe (and it's not even unlikely) that one of you is right with their theories, it was late, I was tired and I have already been flying for a couple of hours before the time of crash.

 

However, I would really like to move the focus of this thread back from blade-smashing-trim-destroying-sams towards the question: "It there a chance that I did not err and might have encountered such a phenomenon as described above, or is it technically impossible that the Ka-50 (in this simulation?) can enter such a state?"

 

Thanks again

[GGTharos]

No. A vortex ring causes a loss of lift. In order to spin you need a rotational moment which comes from having pedal input (whether this is generated by differential torque or a tail-rotor doesn't matter, but we focus on the differential torque since we're flying a Ka-50).

 

Should you happen to damage your rotors in such a way that you lose lift AND one rotor provides more torque than the other, then you might run into something like this - you lose lift and you start spinning, you don't realize your forward velocity was already slow, and you eventually enter VRS ... while spinning.

 

Crazy theory though ;)

[159th_Viper]

"It there a chance that I did not err and might have encountered such a phenomenon as described above, or is it technically impossible that the Ka-50 (in this simulation?) can enter such a state?"

 

Watch this Track:

 

[ATTACH]30428[/ATTACH]

 

Is this close to what you experienced?

[eoh]

Thank you for your answer. In the meantime, I managed to upload the track (64mb):

 

http://rapidshare.com/files/272254357/client-20090826-201307.miz.trk

 

It didn't work for me the first time I tried to watch it, however, I will try again now. Btw, does speeding up the replay (CTRL-Y) affect its accuracy?

[eoh]

@Viper: Yes, that's it. With the only exception that I crashed ;-)

 

Given from your control's input I'd now assume that I did not consequently enough steer against the spinning rotation and that my height was too low to try it long enough (frankly, I panicked :joystick:)

 

Okay, this settled it for me. Thank you very much again.

Edited August 27, 2009 by eoh

[nemises]

yep, once it starts spinngin, it take s a hell of a lot of pedal to stop it again

[159th_Viper]

 

Okay, this settled it for me. Thank you very much again.

 

Jolly Good - Glad you got it sorted :)