Heston Canal
I have been quizzing my mother who is still alive and kicking at 96 - and who has a very good memory of the period - and she is quite certain there was no canal spur to the aerodrome at any time (on the route shown on the OS map at least) from about 1938 onwards when she moved into the area.
Friends of hers (one of whom worked for Heston Aircraft) lived in a house in North Hyde Lane near Wentworth Road, in front of which, the canal spur is shown passing on the map, and she can never recall anything other than the current open space being there. So, if the canal spur ever existed it must have been from before that time and filled in when new housing was built around North Hyde Road and Wentworth Road.
The canal's purpose seems a little unclear to me unless it dated from the 1920s BEFORE the aerodrome was built when a lot of the land in the area was clay brickfields. It seems logical that barges may have hauled bricks to the growing London suburbs of that time but I can't picture why an aerodrome would need a canal.
Anyway, it seems the 1947 OS map may be in error - possibly, I imagine, because the aerodrome was still under military control and accurate civilian mapping was discouraged (or the surveying was just not very thorough in the immediate post war period and old info was used).
Out of interest her main memory of the aerodrome was from the war years when the loud, nearby, anti-aircraft guns there gave plenty of ongoing and scary background noise during air raids which, in particular, terrified her dog and didn't do much for the nerves of the humans either! I am pretty sure my late father (ex RAF) once mentioned that Hurricanes operated from Heston for part of the war and, I might be wrong, but I think he suggested that some of Northolt's Polish Air Force contingent spent some of the war there - or at least were frequent visitors.