Perusing some old airport mayflys for Luton, Britannia were using the "A" and "B" suffixes in 1977 apart from their trooping flights to Germany which were always 3 figures in the BY9** range.

Sorry,a bit late,but it's the first time I've looked at this thread.There was a trial of alpha-numerics in the very late 80s,or early 90s.I didn't arrive at LATCC until 1988,and I can remember an occasion when on the Pole Hill sector,I had a Dan Air,and a Midland on the frequency at the same time,both of which had the same Alpha-numeric suffix to their call sign,and all three of us were becoming confused at times.They were something like BD498AB,and DA498AB.Thankfully the trial didn't last long !

My memory dims,but wasn't Speedbird 1 (or as they would say "Speedbird concorde 1") the EGLL to KJFK service ?

Yes.

BA (as distinct from BOAC) has never adopted the east/west-odd/even rule.

The first trial of alpha numerics was done in conjunction with Dan-Air in 1982. I can, if necessary, explain how the system worked

Hi Bean,yes ,I'd be interested to hear about that.It's a long time ago now,but I still remember the event I referred to,It was at a weekend,so I was working the Pole Hill/Irish Sea sector 'bandboxed',and I think the Dan was a joiner out of EGNT,can't remember much about the Midland,but they were taking each other's calls,and I did report the circumstances to the supervisor's desk at the time.

Dan Air used alphanumeric callsigns for their LBA-based Link City flights. The evening flight to Glasgow was DA B6ER and the return was DA B6ES. I don't remember if alphanumerics were also used on the Channel Islands flights.

Didn't this change when the flight numbers went over to the new BA logic in about 1978, round about when the "BeaLine" callsign was dropped. For many years, only Lufthansa and Canada 3000 operated on the North Atlantic with even numbers west and odd numbers East. So "evens go East" was almost completely flipped by the late 80s early 90s.

Not totally correct. I started listening to ATC in 1962 & Swissair & Alitalia were using even numbers forAtlantic westbounds then; & continued to do so throughout my years as an ATCO - 1971 to 2008.

Oh you're right I forgot about Swissair and forgot I ever knew about Alitalia, which I would have done given hours listening to Scottish high level and Shanwick.

Another couple of callsign questions. Maof Airlines (Israel) operated flights to the UK 1981-1984. I don't recall them using "Maof" as a callsign, believe it was "Mike Golf", with MG being their 2 -letter designator for ATC purposes, OJ being used for ticketing etc.
Same question about Altair (the Italian one), operating Italy-UK early - mid 80's with Caravelles. Don't think they used "Altair", possibly "Sierra Mike" which was their 2 letter designator.

Grateful as always for any confirmation (or otherwise).

Another one for anyone whose memory is better than mine. Executive Express, based Luton, operating Cessna Titans 1977- 1983 (ish) also Cessna 421s and a Beech 200. Pretty sure they flew under flight numbers rather than registrations, anyone recall their callsign?

Actually, Dan-Air call were not so simple
Positioning flights usedcthe number 99 followed by the last two letters of the aircraft reg. Eg 99victorgolf.
The only other use of alpha numerics was an experiment in 1982, all letters of the alphabet were used except A and D.
1st letter was B then a 4 denoting a 1-11 or a 6 denoting a 748. So 24 letters used. Eg DA001 B6BB, DA024 B6BZ. DA025 C6BB, DA048 C6CZ.
These were the only examples of alpha numerics used by Dan

Actually, maintenance flight numbers used 89, not 99.

That's interesting about Altair and SM -
As Societa Aerea Mediterranea (SAM) (MQ) I seem to recall SAM's flight numbers were always SM, maybe MQ came later?

Better known as IAS Cargo Airlines. Normally the call sign was abbreviated to “Fox Fox” (designator was FF which supposedly stood for “freight flight”).

Pelican Air Transport aka Pelican Cargo callsign was DP and "Pelican" Pelican callsign had been used unofficially by Air France for their cargo operation but had never been registered by them!

I was under the impression that the two numerals denoted aircraft type? I definitely remember 79, 89 and 99, followed by the last two letters of the reg. operating into Newcastle.
Another memory to add to the mix - training flights seemed to always use the callsign DAN51T.