.......being required to do a 20 minute astro fix schedule across the Atlantic to check the accuracy of the INSs. How daft can you get?!!!
'cos no one believed INS would work at first, it was black magic. "In The Beginning" we had an early INS experimental thinggy fitted to the sidewall of the fuselage of a 707 freighter main cargo deck, it measured about 3ft by 1 ft and was full of winking lights and clicking relays, there was a long "boot up" procedure to follow,and I remember being amazed that, having started the thing up on chox, by the time we had got to the end of the runway it had moved 1 mile West and 1/2 mile South ( or thereabouts ) PFM ( Pure F****g Magic). I was impressed.
We treated INS in those days like I now treat a "Glass Cockpit" fitted to a club Microlight that I'm supposed to be an instructor for, i.e. "don't touch anything, and WTF is it doing now ?" I'm told this is what a dog thinks when it sees television ?
........old Hoover pipes to use diff pressure to vacuum clean the flight deck.
I've been told that Air New Zealand fitted a vacuum arrangement to the sextant mounting of their DC-8's. Can't comment.
The 707-336 had a Kollsman sextant. What did the 436 and VC10 have?
I think it was a Kelvin Hughes design manufactured by Smiths Instruments ? One difference was that the Kollsman had a mechanical pendulum permanently visible in the viewing chamber, whereas the other one required a bubble to be created by turning a large knob on the side each time, size of bubble you "custom created" had an effect on the viability of the sight, i.e. smaller was more accurate, but harder to "chase" the star. Overall I preferred the Kollsman.
The weather ships had a pretty good idea where they were, they had access to better Loran and navigation equipment than we did, weight not being a consideration for them, they steamed around in a "box" and sent their position out as X and Y co-ordinates of a square grid, which was also printed on our chart, so the morse code ident. would be something like "C(for Charlie, or whichever ship it was,) then-D-5" which put them in a small square, maybe 10 mile sides but as explained earlier this was small beer in the scale of things.
Smart thinking to follow PanAm's INS, except..... Once approaching JFK I was vectored for a visual approach to 22L from Deer Park ( or similar) to follow preceeding traffic, which was number one, a PanAm 707, did I have the traffic in sight ? Yes.
We followed PanAm, who made no attempt to turn on to the centre line and eventually passed through it, I then asked tower if I could make my own interception as I had the runway in sight and preceeding traffic had made no attempt to join. I was cleared to land, then we heard "Err - Kennedy Tower, PanAm One requests vectors to final ". Won one ! Turned out it was an SFO based PanAm crew who were less familiar with JFK then we were - at least that was their story when we met them in Customs.