Flight KSP2 Turns Off Rocket Engines Automatically on Staging When this Should Only be Done by the Player. (KSP1 Video for Comparison)

[Anth]

Reported Version: v0.1.2 (latest) | Mods: none | Can replicate without mods? Yes 
OS: Windows 10 | CPU: Intel i9 9900K | GPU: Nvidia 3070ti | RAM: 32GB

This is How it Happens in KSP1:

Spoiler

• Player needs to wait for the moment that the tanks are empty and the engine stops firing to stage.
• If they stage too early the upper stage will have problems moving and won't respond correctly.
• If done way too early they can get to see their previous stage fly off by itself which is actually pretty awesome to watch.

Video Evidence of premature staging in KSP1:
Open KSP1+KSP2 Videos.zip attached below and play KSP1EnginesNotTurningOff.mp4

This is How it Happens in KSP2:

Spoiler

• Player stages whenever they want.
• The previous stage turns itself off automatically.
• No consequences.
• And no impressive first stage flying off by itself.

Video Evidence:
Open KSP1+KSP2 Videos.zip attached below and play KSP2EnginesTurningOff.mp4

Action Groups aren't a Work Around.

Spoiler

It appears that manual staging isn't necessary for the automatic turning off to work.
Add engines to action groups and make the second stage fire first and the first stage engine will be removed from staging and wont fire at all.
Also it appears I can change between the stages as if the game think they are different crafts when they are still attached even though a decoupler wasn't used.

Video Evidence:
Note the attempts to relight the engines on the bottom towards the end. Turned off top engine using action groups. Attempts to start the first engine using another action group.
https://youtu.be/6Nvdul2a-iY (9 Seconds)

Steps to Replicate:

1. Launch ActionGroupTestCraft
2. Press 1 to activate First Stage
3. Press 2 to activate Second Stage
4. Press 2 to deactivate the Second Stage
5. Press 1 constantly to see the attempted relight

Additionally:
Also attempt to change to the first stage by double clicking on it.
Then Use [ and ] To change between the same craft. The game shouldn't be thinking they have separated.

Craft File:
https://www.dropbox.com/s/0a3fdkphp5krxsp/ActionGroupTestCraft.zip?dl=0

Included Attachment:
KSP1KSP2Videos.zip

Hot Staging:

Spoiler

According to wikipedia: To light the engine(s) of a rocket stage while still attached to the stage beneath it.
The second stage will start firing before the first stage stops firing.

KSP1 could do this. KSP2 cannot.

Showing KSP2 without staging the decoupler (works exactly like this without a decoupler)
https://youtu.be/4B9eO9CqPxc (12 Seconds)

Educational and Emotional Perspective:

Spoiler

Educational Point of View:
A real rocket has MECO (Main Engine Cut Off) which happens via a computer as below:

• At a certain point the rocket engine is turned off (With fuel still in the tank)
• Then there is a pause while the next stage gets some distance (caused by some sort of force)
• Then the next stage activates its engines.

Rocket engines in reality are controlled by computers.
Rocket engines in KSP2 are controlled by human computers.

If we saw a real rocket engine miss its MECO point the decoupling would be catastrophic.  Shouldn't we be letting the player experience this?

The Emotional Side:
There's the fear of staging too early.
And the emotional satisfaction of timing the stage correctly because the possible consequences.

Edited June 6, 2023 by Anth12
Adding Hot Staging Section and Action group Section

[Sea_Kerman]

Also, what if you want the engines to keep running, perhaps for a novel stage sep method?

[linuxgurugamer]

There is also a mod for KSP 1 called Sensible Staging which does this

[Anth]

Excellent Point . Hot Staging.