15-21 foot seas in the hours it was having trouble....and subs can’t take that on the surface...they would have capsized and foundered. The South Atlantic is VERY unforgiving. Submerging was the only call, unfortunately.
Well, snorkeling in those seas is asking for it. They would have had to have taken on water to keep from broaching, so they would be heavy. Any loss of propulsion would have been disastrous.
I remember being a periscope depth when the Captain ran a reactor scram drill on me. I ordered the Engine Room to shift propulsion to the Emergency Propulsion Motor, while they acknowledged the order, another alarm went off in Maneuvering and they kind of forgot about the order.
At about 2 knots forward speed I lost all Bernoulli effect, and started to sink. I was 30,000 pounds heavy because of the seas, and the pumps couldn’t have gotten in out in time. At 200 feet going down, I ordered a 15 second blow of main ballast. It took two more to get our descent stopped and headed back toward the surface.
That woke up Maneuvering, and they gave me the EPM, so that I was back up to speed and could vent Main Ballast before I got to Periscope Depth.
The only thing the Captain said to me was that “to reduce the load on the laundry, you should get on the 1MC before using Main Ballast for depth control.”
Vaya Con Dios!