How ironic. This whole “engine run” issue has been fought over in all the FAI classes of radio control soaring for 10 years now. Some of the classes involve scale birds (JS-1s, Arcii, ASG-29s, etc) with spans up to 30 feet. It’s as contentious as ever and makes a Chinese fire drill look like a Marine parade. Good luck.
Remember when men where men (post above) and gliders didn’t have engines?? Old fashioned? Proudly! Snobbish? To the max!