Going back in time... In the 1952-3 era, a York's calculator was made by Dalton ( not yet a Jeppeson), the A/P when it worked, tended to cycle the elevator about 30 - 40 times per minute, the A/T would be manually adjusted. The Navigator was human and the ECAS was in Morse Code at 20-25 wpm by another human, using a key.No CVR invented yet.( Two Pilots, one Navigator, one Radio Officer and one Flying Spanner, plus a stewardess for 36 passengers.)
My fourth and last flight in a York to KIN was from the UK via Lages, ( two 8 1/2 hour flights to Gander(N/S), then Bermuda to Kingston ). Usually we had routed via Keflavik.
Skyways York G-AHFA was the third airliner to have ditched in the N.Atlantic, on 2nd. Feb. 1953, sending out a position report followed quickly by an interrupted "SOS GA- " ( Like AF447 people knew very soon, WHEN and, to some extent, WHERE, whatever happened had occurred...) The SOS was some 6 hours and five minutes after T/O.
After about 6 hours night flight from Lages, fuel which had been in the 540 gallon Centre tank at Take Off and then subsequently transferred to the two inner tanks, when their fuel had been consumed ( each of which fed both the two engines on their own wing) would start to be used.
The water tank filler (40 gallons ?) was close to the Centre tank filler. I cannot recall whether they were marked differently. Both had similar flaps hinged at the front then fastened down with a Dzuz fastener. ( It had been part of my job as a Second Officer to check that they were screwed down.)
IF, and just if, water HAD got into the centre tank, the four fuel pressure warning lights on the flight deck would have remained out... All four engines would splutter to a stop...
An oil slick was found after a day or two 120 nm. SW of LKP. ( A number of oil slicks were found when first looking for AF447, but not related.)
120 nm. from LKP...? The aircraft was not equipped with LORAN... The sky might have been too overcast for ASTRO. It sometimes is, below F/L 10.0.
At the Inquiry, the Solicitor General " Ruled out Contaminated Fuel..."
How could he have been so certain ? The aircraft was never found...
As IGh in #230 on 7th April wrote :
" Investigating Authorities can be led astray... "