IO I did not see a smiley on this post, I hope that was an oversight!
“How often is the empty weight checked and by who?”
To get it installed requires paperwork, which includes the weight of the installation plus the old empty weight. It would also get checked after any accident or incident if the insurance or the CAA thought there was a problem.
”It cannot be checked more often than at the Annual, so..... you remove the transponder for the Annual, possibly leaving behind just the antenna. The antenna can be installed (concealed) inside the hull if the hull is composite.”
So, you are helpfully suggesting that people fly illegally and with a set-up, which would not work? Most of these machines will be composite – carbon fibre – and no you cannot hide the antenna in the fuselage cuz it wont work, would be illegal and no avionic shop would do it (we are talking factory built £80k+ machines)
”The empty weight is meaningless in safety terms because all the pilot has to do is eat a few more burgers and ... and GA pilots are hardly a health conscious lot.”
I and many others have tried to get the CAA to relax the rules to allow the installation to be excluded from the empty weight calculation. Many parts of the world have similar exceptions, but the CAA would not budge. Perhaps it would have been a better use of my time posting ridicules bits of advice on an aviation forum…
It is rules like the empty weight rule that make the VLA solution, which has no such silly rule, a better option.
Rod1