Even in the 80s you could have problems. In April 82 just after the Argentinians had invaded the Falkland Islands, and before the Victor tankers deployed to Ascension Island, there was an AAR trail for Harriers to Goose Bay. After taking on fuel in a Tanker/Tanker bracket at Stornoway we set off across the North Atlantic in company with 3 Harriers. Shortly thereafter the Doppler failed. The forecast wind was 270/40, so this what we had to use for DR. Fixing was not possible as although there were several Position Lines to give a Latitude check (Stavanger Consol, Faroes NDB and Sun Shots) there was nothing to give a Longitude check. The wind was actually 270/120!! Fortunately we had 3 INS equipped chicks with us to give us position updates until we could get a N/S Position line from Iceland. If we had been on our own we would have been 80 nm in error after an hour.
On the return leg, as first in the stream, in a different aircraft with working Doppler we transmitted the actual winds/positions to the following stream of Victors.