To add to the comment from the VK5 above and some other comments on aerials and groundplanes. VSWR is a good indication that the circuit i.e. the feeder and aerial are tuned to the frequency in use. However it gives no indication of efficiency. Many shortened aerials give a very good VSWR, but so does a 50 ohm dummy load!
In most cases an aluminium aircraft with a well bonded structure will provide an excellent groundplane, as will a fibreglass one if sufficient conducting tape or foil is applied as a ground plane. The short rubber counterpoise some use is more to achieve a match (VSWR) than to provide effective radiation.
There is no need to run any wires back from foil groundplanes to anywhere, just ensure that the braid of the coax is well connected to it.
From what I've seen there are few standards when it comes to radio connections, in fact non-standard seems to be the standard! Pleased to hear that somebody got a good response from Xcom.