Scripted Cobra by when in direct control mode (S key)

[Gierasimov]

I feel let down with my recent purchase of Su-27 module.

 

Is it just me or is the Su-27 performing Cobra maneuver “out-of-the-box” with single key press now?!?

 

I have seen some older DCS tutorials on how to perform Cobra in DCS and I was also interested in Direct Control Mode since PFM was introduced for this brilliant fighter. All the time they say – press S to disengage FBW and go into direct control mode. I went in to options and I see S mapped to the command but with (Cobra) suffix.

 

Took Sukhoi for a spin, leveled at 3500, speed 450, press S and WTF?!? Su went into Cobra all by itself….

 

 

Anybody else with the same problem?

 

 

Side / steam releasing note --

 

Was it done on purpose? If yes, then why bother to create PFM, script take - off and landing as well and since autopilot is capable handling the rest, and systems are in simple mode... sell it as Su-27 H.A.W.X. edition or Ace Combat ...

[Bushmanni]

Try pressing the S key while you push the nose down to see if it pulls up into cobra again. :smilewink:

[Pocket Sized]

Did your nose go up or down? Center your trim before pressing S.

 

Trust me, it's not scripted. Were you low on fuel? It gets really tail heavy and loves to "deep stall" when close to empty. Also, what sort of load out were you carrying? Wingtip stores move the CG even further aft.

 

(Deep stall = nose goes up and won't go back down, term comes from the F-16)

[Gierasimov]

Trimmed in level flight, 50% fuel, clean

 

Did your nose go up or down? Center your trim before pressing S.

 

Trust me, it's not scripted. Were you low on fuel? It gets really tail heavy and loves to "deep stall" when close to empty. Also, what sort of load out were you carrying? Wingtip stores move the CG even further aft.

 

(Deep stall = nose goes up and won't go back down, term comes from the F-16)

 

 

What I meant is, fighter performed full Cobra, not a nose up (or down), not a deep stall. Full and complete maneuver... I will try this again with direct control right from the ramp.

[Pocket Sized]

What I meant is, fighter performed full Cobra, not a nose up (or down), not a deep stall. Full and complete maneuver... I will try this again with direct control right from the ramp.

 

Wait, so you pressed S and the nose went up then back down without you touching the stick?

[Sweep]

Here's what a Kobra should look like...Notice the controls indicator and the entry parameters.

 

AFAIK the switch is indeed labeled "ACS Direct Control (Cobra)" or something like that. A switch left of the throttle is moved when the DC mode is engaged.

 

Skip to 2:50 for the Kobra.

 

[NineLine]

Looks like the vid is private.

[Sweep]

Looks like the vid is private.

 

Whoops, yeah, it is! Fixed!

[Gierasimov]

Yes it did...but I solved the problem now

 

Wait, so you pressed S and the nose went up then back down without you touching the stick?

 

Exactly!

 

But...

I just tried:

In flight pressing S now tossed the nose up and down by around 60deg but without Cobra.

On the runway prassing S disables FBW and all is good, manual Cobra includng.

 

I checked settings again and all seemed good, mapped S to controler button but I noticed that the config file did not update.... So I investigated this: Deleted the config file and recreared mappings to my X55 HOTAS. All works good now. Seems it was controller / config issue now...

 

All good and I am happy customer now. Thank you all for your tips.

[Winston 60]

BTW..... is it ever possible to recover from the inverted flat spin? I mean if you were high enough is there a procedure to regain control? Or is it a punch-out event?

[Drona]

BTW..... is it ever possible to recover from the inverted flat spin? I mean if you were high enough is there a procedure to regain control? Or is it a punch-out event?

 

It is possible, but you need to be high enough. There maybe a procedure, but so far, I've not used any procedure as I don't use the S key/Cobra often.

[Sweep]

BTW..... is it ever possible to recover from the inverted flat spin? I mean if you were high enough is there a procedure to regain control? Or is it a punch-out event?

 

Yeah, inducing pitch oscillations and CoG changes should do it.

 

Also, wheel brake key! Get the pitch/yaw limiter off and you'll stand a better chance, IIRC.

[Pocket Sized]

IRL you would try to recover and probably punch out if you're not recovered by 3km or so.

 

As for how to recover:

 

Idle engines as soon as you see the nose uncontrollably pitching down.

Turn on direct control

Attempt to rock the plane back and forth using full stick deflection

Apparently extending gear/flaps can help, not confirmed

 

If your engines die while trying to recover, you're dead.

[rrohde]

BTW..... is it ever possible to recover from the inverted flat spin? I mean if you were high enough is there a procedure to regain control? Or is it a punch-out event?

 

Given you have enough altitude, you can. I've done it multiple times and you can "rock" the controls to hopefully change attitude. I also drop flaps and gears, and extend the airbrake, to break the airflow and regain some control. It's harrowing, but can be done. :)

[rrohde]

 

Is it just me or is the Su-27 performing Cobra maneuver “out-of-the-box” with single key press now?!?

 

 

First off, no need for a thumb-down on a thread when you're not understanding how this works. :thumbup: You also need to be sure to have trimmed the 27 for level flight before attempting any of this.

 

And no, the "S" key only disengages the FBW authority on the pitch axis. Maybe you're flying the old "Lock On" where the Cobra maneuver was indeed "canned". :music_whistling:

[hreich]

Here's what a Kobra should look like...Notice the controls indicator and the entry parameters.

 

AFAIK the switch is indeed labeled "ACS Direct Control (Cobra)" or something like that. A switch left of the throttle is moved when the DC mode is engaged.

 

Skip to 2:50 for the Kobra.

 

 

How can one get those control indicators instead of default ones?

[Sweep]

How can one get those control indicators instead of default ones?

 

That isn't default? :huh:

[DarkFire]

Given you have enough altitude, you can. I've done it multiple times and you can "rock" the controls to hopefully change attitude. I also drop flaps and gears, and extend the airbrake, to break the airflow and regain some control. It's harrowing, but can be done. :)

 

This. I don't usually bother with the gear, but the flaps decrease your Vmin and opening the airbrake appears to shift the center of pressure forwards slightly which helps. Engage direct control mode and attempt to 'rock' the aircraft out of the stall condition. If your engines flame out, eject. If you have less than ~4,000m altitude remaining when the aircraft enters the inverted stall, eject. The lowest altitude I've ever been able to successfully recover from was around 4,600m.

Edited October 3, 2016 by DarkFire

[Gierasimov]

Eject! Eject! Eject!

 

(...)

 

If your engines die while trying to recover, you're dead.

 

No, you pull the handle... and hope it is going to work as designed...

[Gierasimov]

No need for such comments thank you!

 

First off, no need for a thumb-down on a thread when you're not understanding how this works. :thumbup: You also need to be sure to have trimmed the 27 for level flight before attempting any of this.

 

Bit rude to tell me off like that, not knowing what I was doing (which you would if you took time to read what I said). My thread, my thumb, no need to chime in if don't feel like to.

[Ironhand]

This. I don't usually bother with the gear, but the flaps decrease your Vmin and opening the airbrake appears to shift the center of pressure forwards slightly which helps. Engage direct control mode and attempt to 'rock' the aircraft out of the stall condition. If your engines flame out, eject. If you have less than ~4,000m altitude remaining when the aircraft enters the inverted stall, eject. The lowest altitude I've ever been able to successfully recover from was around 4,600m.

I've also had a decent amount of success popping the chute as the tail is oscillating up.

[Stuge]

Here is Stuge's Su-27 inverted deep stall recovery procedure , guaranteed to work if executed correctly:

 

1. Throttle idle immediately to prevent flameout which would hinder recovery possibility

 

2. Reset trim (Ctrl-T) and make sure gear, flaps and airbrake are RETRACTED.

 

3. Fire off all missiles with launch override (Alt-W)

 

4. Engage direct control (S key)

 

5. Initiate oscillation if necessary by pulling full stick back deflection. This will move your nose TOWARDS THE SKY!

 

6. Once the nose stops moving skyward (at the apex) release the stick to neutral position. This will speed up nose movement TOWARDS THE GROUND!

 

7. Once the nose stops moving towards the ground (lowest pitch), pull the stick fully back again.

 

8. If the nose starts moving again towards the sky, keep the stick fully back until the apex and resume from step 6. This will increase the oscillation. Once you reach this step with steep enough pitch (more than -45 degrees) then the nose starts moving even more downwards and you will have recovered!

 

Do not push the stick forward past neutral position at any point, this is likely to dampen the oscillations and you will have to start the recovery procedure all over again!!

 

The correct timings to change the control input between fully back and neutral is when the nose stops moving at the top and bottom of the oscillations. Do not change control position while the nose is moving upwards or downwards!

Edited October 4, 2016 by Stuge

[DarkFire]

I've also had a decent amount of success popping the chute as the tail is oscillating up.

 

Analogous to the MiG-21 spin recovery technique... Interesting! I'll give that a try next time I manage to get it to depart.