Round trip time: the year holds seven trips, the eighth falls short

Split one year into states that cannot overlap. On the worked ledger 8,400 operating hours hold 7 complete trips, and the eighth stops inside positioning 11 days short. No trip is priced here.

Live result

7 complete trips fit in the calendar you typed, and the next one stops in empty positioning.

Days used in the next trip34 days
Hours it still needs264 hours

Port time at each call is what moves the whole count.

Try a scenario

Trips across port time

Port time per call24 hours

This whole-hour value alone moves the staircase. The sweep checks every hour inside the typed bounds.

Adjacent checked changes

First change above: 83
First change below: 7

The reconciled record

Complete trips: 7 trips
Hours in one trip: 1,083 hours
Hours used in the partial next trip: 819 hours
Days stranded in the partial next trip: 34 days
Hours still needed: 264 hours
State that stops the next trip: empty positioning

Progress through the partial next trip

Filled segments are the time already consumed in the fixed state order.

loaded passage: 600 / 600 hours
empty positioning: 219 / 240 hours
waiting: 0 / 100 hours
working: 0 / 143 hours

Every calendar hour

loaded passage: 4,800 hours
empty positioning: 1,899 hours
waiting: 700 hours
working: 1,001 hours
planned maintenance: 240 hours
unplanned downtime: 120 hours
Reconciled calendar: 8,760 hours

Annual ledger and trip sequence

Calendar lengthdays

Loaded passagehours

Empty positioninghours

Waitinghours

Other working timehours

Port calls per tripcalls

Planned maintenancehours

Unplanned downtimehours

Sweep fromhours

Sweep tohours

Boundary

The count follows the typed annual ledger and fixed state sequence. It does not price a trip, turn saved time into revenue, rearrange states, or optimize a schedule.

Here is the maths

The formula, in words

Convert the calendar to hours and subtract planned maintenance and unplanned downtime. Add the four trip states, including port calls inside working time. Divide available hours by cycle hours and keep the whole part. Walk the remainder through the same state order until the first state cannot finish.

H_a=24D-H_p-H_u

where $H_a$ is available hours, $D$ calendar days, $H_p$ planned maintenance hours, and $H_u$ unplanned downtime hours.

A worked example

A 365 day calendar has 8,760 hours. Subtracting 240 planned and 120 unplanned hours leaves 8,400 operating hours. One trip uses 1,083 hours. Seven trips use 7,581 hours and leave 819. The partial eighth clears 600 loaded hours and uses 219 of 240 positioning hours, so it needs 264 more hours, or 11 days, to finish.

600 + 240 + 100 + 95 + 2 \times 24 = 1{,}083

What this does not model

The ledger does not optimize the sequence, average leg speeds, price a voyage, infer revenue, test whether maintenance can move, or claim that the partial next trip can place its remainder in another state.

What the sweep checks

Port time per call is checked at every whole hour between the two typed bounds. Equal trip counts are compressed into bands, and the first changed count above and below the current hour is named.

Source basis

The mechanism is public dimensional arithmetic and a finite capacity ledger. It describes productive calendar capacity and operational friction without reproducing text from a sold source.

The whole record prints. Your browser can save it as a PDF instead of printing it.

Revenue, price, and schedule recommendation fields remain outside this instrument and receive no answer.

Annual round trip record