Yes, I believe that it was Douglas Bader who was quoted as saying: "Regulations are for the obedience of fools, and the guidance of wise men". There's a lot more truth to this than the humour at the surface would suggest.
When I read and understand the myriad of design standards and regulations, I see a lot of wisdom, and hard lessons learned buried in there. There's not one I have ever read, with which I wholly disagree. However, it's how they are interpreted and applied in the "practical world" which is very subjective. I frequently find myself applying one interpretation, based upon my experience with certain types of aircraft, where another person (okay, the government regulator) has another interpretation.
Sometimes, I learn something from the experience presented by the other person, sometimes they don't seem too....
Thanks to all who contributed. I found a very simple device that fits the "cigar lighter" socket and allows 2 connections. Each item I use draws very little amperage so well within the rated limits, cost was £4.00 and no paperwork needed, job done! Many thanks
I have purchased about 5 different cigarette lighter to twin USB adapters until I found one that can both handle 24V and actually deliver the 2.1A needed for iPad 3/4. Unfortunately it was not one of the flush mount adapters but a larger one that met all criteria.
I am planning to install USB sockets into my dashboard and connect them behind the dashboard to the cigarette lighter. My mechanic doesn't object ("doesn't care" is more accurate).