Warships on shore leave; how many crew on leave at a time?

When an aircraft carrier docks at, say, Japan and the crew go on shore leave, do they have to take turns by position so that at any given moment the carrier has enough engineers, pilots, mechanics, etc. on board?

Yes. You can’t just abandon the vessel entirely.

But “enough” may be a pretty small contingent; you don’t necessarily want to keep the vessel in a state of permanent readiness such that aircraft can always be launched within 15 minutes of a decision, for instance, so the contingent needed to stay on board may be just those necessary to maintain the central services of the vessel, which might be quite a small group, relative to the entire complement.

My answers are from my time aboard the aircraft carrier Enterprise (CVN-65) and 1.5 Western Pacific (WestPac) deployments in the mid-1980s. Also, I was ship’s company (1 of 3000 ± personnel permanently assigned to the ship) but I believe the answers apply to the embarked air wing personnel (2200 ± who are onboard during assigned times).

The answer is “it depends” including but not limited to: the location; if the ship is pierside or anchored out; the duration of stay; the reason for coming into port; and other things I’m probably forgetting.

Each department divides its personnel into duty sections of roughly equal numbers and qualifications to fulfill its requirements for the safety and security of the ship (cleaning spaces, feeding the troops, receiving supplies, filing reports and sending communications, making repairs, operating/shutting down or starting up the reactors and boilers, ect) and standing watches; having 5 Duty Sections was usual, though 3 Duty Sections was not unheard of.

So when everything necessary to get the ship tied up pierside or at anchor, Duty Section 1 is in charge and Duty Sections 2-5 can go on liberty. The following morning Duty Section 2 takes over and Duty sections 1 and 3-5 are on liberty. (Sometimes all personnel in all Duty Sections are required to return for morning muster and to be informed of any changes/updates but afterward the non-assigned Duty Sections are released for liberty; working liberty ports are like being in homeport in that everybody is due onboard at 0700, works a normal day and the non-Duty Sections are released for liberty at 1630).

Aircraft carriers don’t get underway at a moment’s notice; if that was a possibility then the carrier wouldn’t go into port. We had a 72-Hour Checklist for getting underway from our homeport or an extended port visit (3 weeks in Subic Bay, Philippines).

As for as the flyboys, many/most of the fixed wing aircraft would fly off to an airfield before we entered port since they’re of no use when they can’t be flown (no wind over the deck). I suppose helicopter operations could be conducted while in port but I don’t recall it happening. Supplies would be craned on when we were in a friendly port (and we never went to a non-friendly port).
Helos were operated when we were at anchor and we did launch (but not recover) our S-2 while at anchor way off of Qatar (we slowly rotated the screws and put the rudders over to one side and slowly twisted around the anchor till we got what little wind there was over the deck. The S-2 was on the aft end of the ship, stood on its brakes and ran the engines up then used about 800 of 1000 feet of the flight deck to take off.). From anchor, personnel transferred ashore using motors whale boats (which were never used for whaling) or commercial water taxis (the Captain [and others with permission] used the Captain’s Gig).

TL;DR 1/5th to 1/3rd of the crew remains aboard.

(and that ends my trip down Memory Lane)

When I was serving on a submarine, generally about 2/3rds to 3/4ths of the crew could leave the boat at a time. There was always a duty section onboard – enough to watch over the systems, guard the ship, and start up the reactor and get the ship ready for departure in an emergency. There would be a “watchbill” made out in advance – a schedule of which crew members would be on duty on the ship on which days. In port, “duty” generally lasted a single day.

Are many/most/all fixed-wing aircraft truly incapable of a carrier launch without a headwind? Or is it just harder on the aircraft’s engines and ship’s catapult to do so (and so wise to avoid when possible, as when coming to port)? It seems like a major operational deficiency if a carrier becomes utterly useless when main propulsion is disabled; one lucky hit with a missile or torpedo could take the entire air wing out of the fight.

I had the same question as Machine Elf; it seems like an awfully tough constraint for a carrier to only be able to launch jets with a headwind; also odd that the catapults and engine could get the airplane to 95% of the airflow needed for takeoff but not 100%.
Anyway, thanks everyone for great responses.

If some random emergency did happen and the carrier needed to haul ass, would they summon everyone back aboard the ship and fire up the reactors, or maybe even leave with only the 1/3 crew aboard and try to get the other 2/3 back to America separately?

When I was in the Merchant Marines my ship delivered jet fuel to the aircraft carrier Constellation while it was in the Philadelphia Shipyard. I had speak with the commander of the ship on an issue with the time it was taking to transfer the fuel. He apologised telling me that he was short handed as he only had about 4000 crew aboard out of 5000+. I was astounded as there were no jets on the ship and assumed the support crew for them was mostly on leave. So, from that one experience I’d say they let around 1/4 to 1/5 oy the crew off.

That was the general plan.

The emergency was either to get away from the pier and or country we were in as the crap was hitting the fan there. As you allude to, leaving the crew there is problematic from their safety point of view.

The other reason is that we needed to be somewhere soon, usually to support a mission. The problem there is that you just can’t sail the ship all that long or effectively with only one third of the crew. You certainly can’t fight it.

If it absatively, posilutely was necessary to launch aircraft from a non-moving carrier it could be doable but carriers aren’t designed to do so, just as submarines aren’t constructed with wheels so they can operate in Kansas nor are air stations designed to pick up & move hundreds of miles when threatened by inclement weather or invading hordes.

Real pilots can explain better than I but every knot of headwind provides 1 knot of lift. If an aircraft launches at 100 knots and there is a 25 knot headwind, then the aircraft only has to accelerate to 75 knots before there is 100 knots of airflow/lift over the wings. Likewise, if there is a tailwind of 25 knots, the aircraft has to accelerate to 125 knots to achieve 100 knots of airflow/lift over the wings to launch, that’s why airports use both ends of the runway whereas the ship will maneuver for the desired airflow (and adjust the catapults). The catapults can only be dialed up so far before the damage themselves or the aircraft. Different aircraft have different weights so the steam to/power generated by the catapults are adjusted accordingly (as are the arresting cables for landing).
Anyways, without the wind over the deck or with negative wind, the aircraft has to be lighter to achieve it’s launch speed in the length of available flight deck; less weight means less fuel and fewer weapons for the mission (and the fat pilot can’t fly :slight_smile:
When the carrier is underway, it can adjust its course and speed (Fox Corpen) to take the prevailing winds into account; if there’s no wind, the carrier goes at 25 knots in whichever direction it chooses.
Until an engineer comes on duty in, I’ll continue.
A carrier intakes lots & lots water to operate. The reactors require water flow for its operation, as well as water to make steam for the catapults/arresting gear and generating electricity & drinking water & HVAC (plus the swirling steam for dramatic movie scenes). In port or when not underway there’s not much water flow and the water depth is liable to be shallow and dirty, which clogs the intakes & filters & condensers. When a ship is in port, steam & water & electricity are provided by the base (called hotel services), that way the ship can shut down equipment for repair/replacement/rest.