Yeah, no problem. I'm not the most knowledgeable person about logic in this game (that award would most likely go to Talrey, who wrote the guide I linked), but I figured I could quickly rig up a simple error-proofing circuit, and once I did that I thought it would be shame not to share it with, along with the guide that helped me understand the logic system in the first place.

Oh man, I didn't take a proper look at this before as I was busy, but this is a really great mini tutorial. Very much appreciated.

I've included your suggestions in the updated version of the ship, and will definitely make good use of that guide in my next ship. Thanks again!

Sweet, nice one dude. I'll have a fiddle when I'm next in the game and see if I can get it going.

That's a simple work-around that only takes 3 new logic gates, but, if you want a better solution that only uses one button, you might want to try this guide [www.skywanderersgame.com], specifically the Reversing Sequence "ABBA" section, and probably the extendable version option (often known as an ABCCBA circuit).

Here's showing the new AND gate (in red for easy reference) for the cannon logic. Besides the switch seen here, it also ties into the switch for the safety cover on the opposite side. [i.imgur.com]
Important: while the button for the main cannon still ties into the switch, the switch itself no longer ties into the OR gate, but, rather, goes through the AND gate first. Also, you can see here how the switch leads to the XNOR gate on the opposite side for the safety cover circuit. [i.imgur.com]
Here you can see the new AND gate and XNOR gate (both in red). The XNOR gate gets its input from the switch for the cannon on the opposite side. [i.imgur.com]
Here you can see the AND gate get an input from both the XNOR gate and the safety cover button, and then it outputs into the switch. The button now only outputs into the AND gate instead of the switch. [i.imgur.com]

If you want to make the main cannon not able to deploy unless the safety cover is open, you can have the switch that the button for the main cannon activates tie into an AND gate before it ties into the OR gate, and have that AND gate also have the switch from the safety cover input into it.

Then have the button for the safety cover tie into a different AND gate before it ties into the switch, and have that AND gate also have an input from a XNOR gate that gets an input from the cannon deploy switch.