Carriers have a fairly robust Sick Bay including surgical facilities. I don’t remember how many Doctors we had onboard, but I know we also carried a Dentist. The Carrier acted as the Hospital for the Fleet.
I would be curious how advance the Carrier Sickbay is on the Gerald Ford, our newest carrier. I was in the Navy in the 80s. So I’m very out of date now.
The older carriers like mine had 5000 at sea and the Nukes had 6000. Plus the fleet had to add 1-2 thousand more. I don’t think we carried even 10 Doctors. I think it was more like 4.
My recollection is that the IDC on a submarine was trained to do an emergency appendectomy, but I’m sure this would only be done if it were a matter of life and death.
I also recall that the space designated for an operating room was the officer’s wardroom.
In practice, seriously ill or injured patients would be evacuated off the sub. We did this a couple of times. Once was for a sailor who broke his arm. The IDC stabilized the sailor as best he could, and the sailor was subsequently evacuated to shore.
I served on board a fast attack submarine, though I also did a patrol on a ballistic missile submarine as a midshipman.
In a typical peacetime situation, I would expect a boomer to also be pulled off station for a medical emergency, but I’m just making an educated guess here. Other assets would likely be used to make up for the missing coverage.
I think it’s a matter of scale. Even in the Army or Marines, the lowest level a doctor is typically going to be assigned is battalion level, if I’m not mistaken. That’s a unit of roughly 600 people. Below that, it’s combat medics, and above that, it’s Combat Support Hospitals and the various other expeditionary hospitals that do surgery, not just first aid. I get the impression that if you’re on-base, there’s a medical clinic not unlike those in the civilian world that you go to.
So a submarine with a crew of 130-150 just isn’t big enough to warrant a dedicated physician. What they get is someone who’s (as I understand it) somewhere between a nurse and a PA in terms of training. ISTR that they have emergency surgery training for extreme situation- like say appendicitis when the sub cannot surface and offload the person.
But in general subs do exactly what @Francis_Vaughan says; if someone has appendicitis, the on-board corpsman will let the sub command staff know, and they’ll surface and take that person to another ship or shore installation that can treat him. I suppose it’s possible that in wartime, or really sensitive peacetime operations, that person might end up dying from it, if they can’t surface without jeopardizing the entire boat, and the corpsman’s surgery is unsuccessful.
During my time in the army, doctors worked at brigade level, battalion level was a physician’s assistant along with however many medics(usually 4 or 5). Dentists were always divisional assests. When I was at Ft. Riley, they actually had to borrow a dentist from the Airforce base over in Wichita( dentists in the army at the time were scarce as…well, hen’s teeth😁)