How to change ship and still going?

[WolfyPlayer]

Hello mates, today i want to ask you guys, for example: How do i change planes in the middle of a flight, like, i'm flying one plane in the middle of the air, them i switch to another plane to fly under formation with the other one. How can i change vehicles like this? Every time i try to change it says something like this: "You can't change vessels while your engines are ON". Any tip?

[Scarecrow88]

As far as I know you can't swap between vehicles when they are throttled up. The only way I have been able to do any formation flying is in orbit.

[Dun Kirk]

there is a mod which does this

[WolfyPlayer]

there is a mod which does this

Can you tell me the name of the mod?