These kinds of things happen to me all the time. The save button used to crash the game for me sometimes and I would lose work.

Had to edit the title, was creating some issues, my apologies

For This Reason I Never Attach The Cockpit Before Finishing The Work, And I Always Offset The Plane 2.000 To Right, So Even If I Pless This Button Nothing Happen, And I Save The Work Every 15 Minute.

skill issue smh

just save every modification 🤔🤔

How do you accidentally press that button 💀

wow, even the mirror button can do more damage than the undo button

Maybe jundroo should consider adding something that when you press the mirror button a message will pop up that says "are you sure you want to mirror this aircraft?" then you can press confirm if you want to continue

We do a little uploading unlisted posts

I set the mirror the entire craft button to nothing, so that doesn’t happen, I just only mirror individual parts or chunks of the plane anymore, I’d recommend that and also uploading many versions as unlisted to revert back on if something gets really messed up
(Same issue with the undo button, it sucky suck)

that's why i save my build every 10 seconds

just make the cockpit centered

Additionally, the Undo button exists, and works even if you have saved the plane before undoing. Before you respond with some variation of "but the Undo button will undo way more than I want it to", consider the following:
Which would you rather lose? Three or four steps that can likely be redone in 10 minutes, or 10 hours of work?

Alternatively, if you've been prudent with your saves (e.g. not just saving over the same thing again and again), it should be simple for you to go back to an earlier version of the build.

@DogeToTheMoon The second one ("full mirror", which mirrors one side of the entire build over a centerline) is already a two-step process (technically three steps if you count opening the menu, which itself is a separate action). You click the "Mirror" button, pick an offset from X=0 if you want one, and then hit "Mirror".

@HuskyDynamics01 There are two features, one mirrors the part that u selected and the others mirrors from left to right .I used the second one and saving it without even realising.

This is why I never use that feature

What ShinyGemsBro said, though with the addition of the tip that it seems you should probably be saving your progress more frequently. Ten hours is a long time to go without saving.

I'm not sure if this applies to what you're building, but I will typically work on the main body of the plane first, using the mirror function throughout, and only stopping completely once I get to the cockpit, which is the last thing I work on. With custom control surfaces, I still use the mirror function, and then edit the rotators themselves to be inverted.

Doesn't matter if you did it on accident or deliberately. You just have to carefully watch next time where your finger goes(If you're on mobile) or where your cursor is really hovering over(If you're on PC)
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No point in making a huge deal out of it. The mirror option has it's uses, but only in certain cases. The major point here is that you just need to be more careful. You can't get those 10 hours back anymore and neither the time you put into making this forum post, so just move up and go again. If you don't feel like it for now, then don't.

am I the only person who uses the mirror button frequently
ok but fr, yeah the mirror button is a bit weird
it shouldn't just mirror a part's properties and positions, it should also match the part's connection instead of auto reconnecting it after it gets mirrored
and that goddamn, fucking part obstruction on mirrorings... they really should remove that

yeah, they should give an option to remove it

Agree. I never ever use the mirror button, if i must mirror i will use Ctrl+m