The blue green model appears to have an RC carb on the engine so some sort of throttle set up is probably a good guess. Wing spans and engine brands/ sizes would help for looking up the models. Which side of the Atlantic you are on may also make a difference as there were different companies selling kits on either side of the ocean. I ask because one of the engines is a diesel. They aren't unheard of in North America but are much more common in Europe.