SF” seems to denote a low-height design regardless of series — it’s one of the prefixes that Flash Bristow did not cover. Yes there a few L4 towers that are used in a modified form usually to replace former PL1 S towers where diversion or replacement has been necessary in the past. This was quite tight in our test model and may need sanding slightly to allow the tailplane to be slid into place.

Note that the tower bible tells us that L16 D2 crossarms are mirrored, not rotationally symmetrical, but all the examples I have seen are rotationally symmetrical. To rethink one of the most crucial but controversial features of modern Britain: the electricity pylon. I make a specific caveat that all my photos are purely speculative because I have no documented evidence that any particular tower is what I assess it to be (it could be any of the undocumented intermediate variations) — it just helps give readers a better idea than the diagrams alone. I suppose it is quite possible to put an electric motor and battery pack in it, if you really want to.

The RIBA Competition Team, led by Joanne Wallis, provided superb support and expertise at all stages - from planning, to launching, shortlisting and finally judging. It's too late in the year to put together now (I don't build in the summer) but I'm sure this model will be as fast as the Viper and a lot more durable. Whether you use a 3s or 4s battery and for competition or just fun, it will put a smile on your face every time you fly.

I did wonder if there was a more complete copy of the tower bible, but I could only find forum comments from others indicating that what they had was also incomplete.I have been pondering about how to make my own PL design towers using the drawings that I acquired online some years ago and I asked a question on how best to make models e. e. a new(er) 275 kV type based on L12, possibly as there was insufficient justification for larger, heavier 400 kV towers. I need to complete phase 1 of the Tower Bible drawings, plus clean up all my own photos (got a few more types to come, including PL7 DDT and what may be PL4 DD2, although there is another four-crossarm DD type buried here on one of the pages that is neither PL4 nor in the Tower Bible).