I don’t know how the book did this, but it annoyed me in the movie that Ryan, upon meeting Ramius on the RO, didn’t seem sure if Ramius understood English or not. Morse code isn’t some universal language -they would have been sending the instructions in English, unless the captain of the Dallas knew how to send Morse in Russian or Lithuanian or something.
I always wondered about that too, but maybe he didn’t know if Ramius was the one on the periscope.
I know nothing of naval life, but is it impossible that a USN Skipper would not know how to communicate with his greatest enemy.
Again it’s been 25+ years since I read it but in the book Ryan knows quite a bit about Ramius, including that he understood English. Also, they don’t signal him from the USS Dallas’ periscope, they signal him with an Aldis lamp from a surface ship.
Also in the book the ending is much more complex. The US does a switch-a-roo in that they bring an old boomer (the USS Ethan Allen I believe) to the rendezvous point. They have it filled with propane tanks which can be opened & detonated remotely to make it look like it was the RO being destroyed. The Soviet Navy falls for it and heads home, except for one Alfa attack sub that happens to pick up what it recognizes as RO’s unique propulsion sounds. They’re too far away to contact the fleet so instead they pursue, engage, and try to destroy it. RO actually suffers a direct hit from one of their torpedoes, but isn’t sunk because the Soviet designers mounted RO’s lead batteries just behind the outside hull to serve as extra ‘armor’. RO eventually destroys the Alfa, but not with a torpedo, but by simply ramming the much larger Typhoon-class sub into the relatively small Alfa.
Would the GRU in real life not have learnt about Ramius’s disenchantment with the Soviet system and ensured he was eased into a position far away from Boomers?
Only if he talked about it. They’re not mind readers.
And spoke it with the accent of a Scot with loose-fitting dentures. 
“Today, we shail into hishtory!”
They’d met before at some embassy function Ryan remembered, IIRC.
The entire book is far more complex. The entire Royal Navy fleet subplot got chopped out, for instance.
That’s long been my theory about Sean’s unique accent. 
I forgot to mention- When I first saw the movie, because of all the tension between Ryan & the Dallas’ Capt played by Scott Glen (in the film he remains suspicious of the Russians till the end) when they’re all first together on the RO’s bridge and nobody is saying anything, then Connery sees Glen’s sidearm and calls him (in Russian) a ‘buckaroo’ and Ryan laughs because he understands it and then Ryan starts speaking to Ramius in Russian, I always thought that Ryan needed to clarify things quickly lest the Dallas’ Capt be tempted to think it was all a setup and that Ryan was a double-agent! 
Writing the Royal Navy out of things is almost a rule in Hollywood.
Took me a few viewings to notice Skip Tyler standing there- Greer just takes up the scene.
But that is in fact the clue. 
I’m waiting for a Hollywood blockbuster where a plucky band of Americans defeat the French/Spanish navy at Trafalgar.
Yeah! They create the Perfect Storm…
Oooh! And Betsy Ross could make a speech about having the body of a weak and feeble woman, but the heart and stomach of a concrete elephant…
Before going into battle with Al Qaeda.