That's all very exciting that you know this, but the rest of us members are arguably less pedantic and can admittedly confuse things like that. It's possible Fred may have, in his near-tangible excitement ( ) substituted one word for the other, making the connection that most of us would make - that there is little difference between a propellor and an engine.Back on topic, but possibly not so. The Swarm's construction is slow. We know this. It seems like every so often there is a burst of posts that expand this topic by about a page or two then some raincloud is tossed in saying how people should wait until track has arrived or something. The slow tempo of the build for one is obvious, and so long as the thread doesn't stray too far off topic then there is no need to repeat comments and tell people to stop talking about what is easily the most exciting UK coaster construction since 1998.