On 3 August 1964, LCDR Douglas Vrooman Murray assumed the command of the Irex. He had been the Executive Officer of the Sablefish. The Executive Officer of the Irex at the end of 1964 was Lt. Cmdr. John V. Smith.
On 6 October 1964 the Irex again sailed for the Mediterranean for four months to participate in the annual CENTO exercise, MIDLINK VII. The boat left New London in the company of the USS Sablefish, which being an older boat experienced mechanical problems that slowed the transit. For this cruise, see Captain Murray's Irex ChristmasGram sent home from Monaco.
The Irex arrived first in Lisbon, Portugal, on 17 October 1964, and then on to Rota on the 20th, Valetta, Malta on the 24th, Port Said, Egypt on the 28th, transiting the Suez Canal on the 29th in order to participate in exercises in the Red and Arabian Seas. When she reached the Canal, she joined a westerly convoy. For the story, see the account of Ken Robarge. Because of sharks in the Red Sea, instead of swimming by jumping off the bow planes as usual, a barbecue was held on the after deck. The boat docked at Aden, where there was some danger because of fighting associated with Aden's struggle for national independence. The next stop was Karachi, Pakistan, where the Irex arrived on the 7th of November. Conditions there were very bad, including a fight with some tin-can sailors.
After Pakistan, the Irex headed to Aden, Yemen, to arrive November 27, and then to back to Beirut, Lebanon on 6 December. While in Beirut, a science encyclopedia was presented to the Rahamat Charitable Society School for orphans and underprivileged children.
The Irex then headed for Monte Carlo, Monaco, in the company of the Sablefish, arriving on the 21st of December. While in Monaco, many crew members took the opportunity to visit various European cities, while the Irex itself hosted a Christmas party on board for 16 boys from a local orphanage school. Also, three crewmen (MM2 John Field, ET3 Lawrence Hulbert, and EM2 William Hannon) were guests for a Christmas dinner at the palace of Prince Ranier III and Princess Grace (of Philadelphia Kelly Brickworks fame), during which the Princess was presented with a bouquet of orchids.
The boat left Monaco at the beginning of January for a two-week 6th-Fleet exercise, after which she headed for Malaga, Spain, arriving the 15th of January 1965, then on to Rota on the 18th, from whence she sailed back to New London, arriving on the 30th of January 1965.
In either 1964 or 1965, while on training exercises on the Sound, the packing gland around the forward torpedo room sonar training mast gave way, and this resulted in flooding. Getting to the surface under battery power was difficult, and the extreme up-angle needed caused an oxygen bottle in the forward torpedo room to fall and puncture the case of a sonar stack, narrowly missing a torpedoman who was struggling with a mattress to help control the incoming sea water.
Another event at this time, also recounted by Glen Faus, was a battery incident while running standard on four engines on the surface off Nantucket. It was an inspection cruise, and one of the inspectors called a “chlorine in the After Battery event”. The compartment bill in the Control Room called for shutting the main induction and bulkhead flappers, while the one in the Engine Room bill called for keeping the engines running to purge the chlorine. Without the main induction the four engines sucked air from the boat and pulled a 17 inch vacuum aft of the After Battery (not all bulkhead flappers got closed, hence the number of compartments involved). The vacuum pulled hydrogen from the After Battery and it went to 5%, which is 2% over an explosive mix. The chief of the watch in the Control Room saw the high hydrogen concentration and was able to reopen the main induction. Later calculation determined that the main induction, the 36" valve with its 600 lb hydraulics, shouldn't have been able to open, but it did, and the crew survived once again. However, some of the crew experienced ruptured ear drums.
The Irex returned home to New London in mid-January 1965. In March she left to participate in the anti-submarine exercises known as MINIBEX. In April 1965, the Irex took part in the Surface/Air Barrier Exercise with Canada, CANUS-SILEX, to help develop experimental ASW (anti-submarine warfare) tactics. This included a stop over in Nova Scotia (This CANUS-SILEX operation has been reported as taking place earlier in the year).
After this the Irex did Sub-School training and provided services in the Caribbean, returning to New London in November for the holidays.
In January 1966, the Irex again participated in operation SPRINGBOARD in the Caribbean.
In April 1966, Captain Murray was relieved by CDR Denbigh.