It can take some effort presumably because the rope is pulling on the side of the sheave and the angle of the rope out to the side of the boat, but it can be done with a winch on the cabin top. It is easier if you have a masthead spinnaker halyard. BTW an Etchell spinnaker is the perfect size for a masthead spinnaker on an RL28 and ex-racing ones are cheap.
The problem comes with where to store the inflatable once you get it on deck. It limits visibility and makes tacking the jib a real chore. Instead, I built a couple of removable timber struts that project back from the transom a foot or so above the waterline, tipped the dinghy on its side onto the struts and tied it to the pushpit rail. Then it is well out of the way. Of course this did involve removing the motor first and maybe you are hoping to leave it attached.
Thanks Keith...I have Russell Roger's old boat...the Swan...now called Nammu...at the Tin Can Bay Marina...two weeks back...I watched the
same tender being hoisted onto a 32 footer...using what looked to be the spinnaker halyard...though the fellow's winch was on his mast...I have a relatively new self tailing winch but I am more concerned about the mast...we are still novice sailors so much to learn...plan at present is to have a few options...our RL 28 is used primarily in the Great Sandy Straits...and the tender is less for ship to shore...more for fishing and crabbing...but I would like the option of getting it on board the yacht...and then probably deflate it...it deflates very quickly...Cheers...MIchael