@Parkside6568
Based on your observation of shutting down while on working on the landing gear, I would suspect a battery connection problem inside the H. It could be the battery terminal is making poor contact. Remove the battery and inspect the contacts on it to see if you see any signs of arcing. Also use a flashlight and inspect inside the H battery terminals.
Put the battery back in, power it up and then wiggle the battery and tap the outside of the H to see if you can duplicate the shutdown.
Based on your observation of shutting down while on working on the landing gear, I would suspect a battery connection problem inside the H. It could be the battery terminal is making poor contact. Remove the battery and inspect the contacts on it to see if you see any signs of arcing. Also use a flashlight and inspect inside the H battery terminals.
Put the battery back in, power it up and then wiggle the battery and tap the outside of the H to see if you can duplicate the shutdown.