UI/UX Main engine wont turn on after undocking with engine turned off.

BechMeister · May 14, 2023

PC details:

IOS: Windows 11 Home
Version: 22H2
Processor: Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz 2.59 GHz
Ram: 16,0 GB
Graphics Card: NVIDIA GeForce GTX 1660 TI

Bug:
First a little explanation: I have a station in LKO - I had a few "tug drones" connected to that, that I use to push things from one station around Kerbin to the Mun. When they are docked, their engines are offline, except one which I use for orbital corrections. I had to use the Tug drone to push some cargo to the Mun Station, undocked it with the engine still offline, RCS thrusted to the do a hand over take over of the cargo before sending the rocket that flew the cargo into LKO back to "burn up" in the atmosphere:

I have a strong theory that the bug occures because the engine was undocked offline, and then turned online after undocked.

Step by Step Pictures for Context- marked as spoiler, as its not inherently important for the bug I think:

Spoiler

Hand over Take over from the 2nd stage with cargo to small Tug Drone, Which would then connect it to the Big Tug drone.. its because of docking port compatibility.

2nd stage send back to "burn up"

Big Tug Drone, Just undocked from the station - enroute to take the cargo from Medium Tug Drone.

Tug Drone Take Over.

Now detail explination of the bug:

Engine still offline after taking over the cargo.

Engine turned online. As you can see I have 1729 Δv. Full Throttle engine is off. I press space - because some times its like it didn't register the stage is activated.

After pressing Enter the Δv drops to 0 - even thought the fuel tank is full

Solution:

I tried to check if a classic quick load/quick save would fix it - it didnt.

But by making an extra stage, and placing the engine in that like this:

Then pressing enter to activate the stage, makes it work:

Note:

Some times the Δv will show as 0 - but a quicksave/quickload will fix that.