hi,
Welcome to the forum and sorry for the lost.
I only found 6m 54.3s of log record (as uploaded by msinger), which equals to 414.3 sec. But you mentioned flight time T=473.4s. I wonder if there is another log?
From the log available...
As someone who flys the Mavic 3 in the Rain , you cannot just put duct tape over the top vent as water will still find it way in.
This is why the Mavic 3 wet suits have a 3 Part System just for the top vent.
Duct Tape also leaves heavy...
hi captain~
I think Mavic 3 Pro is a good choice. But please be reminded that in terms of rain proof capacity, mavic 3 series is not that impressive as there are ventilation vents on the top of the body and rain easier get in and short circuit...
Tried this before?
https://alienth.cn/products/alientech-deimox-antenna
If it perform half it’s claim, the drone will be out of battery before out of range.