But charting was the province of the Navy. The Navy would say where Ascension was and then the RAF would photograph it and the RE would map it.
PN - you forgot the last bit - 'Then the navy would run into it!'
It was astro nav - or rather using the astro compass one evening - that allowed Frank E.... to prove that Gan was actually 1 mile South of the Equator rather than 1 mile North (or maybe the other way round). The position had remained 'as was' since the Navy had first plotted it and then used it as their secret 'Port T'.
Certainly remember having to learn to do Manual Air Plot during MOTU as a pilot (we were supposed to know how to do every other role in the ac), and still find I use some of the elements of that instruction whilst discussing nav at DHFS.
At least I'll never again hear those dreaded words 'Steady for Astro' whilst flying at low level in gale force winds!