Arrival Times, Connecting Times and the Date Line on a London–Sydney Itinerary
A client asks you to build a London–Sydney itinerary via Dubai on a single ticket: LHR–DXB departing 14:20 local on Wednesday 9 July 2025, block time 6 h 50 min, then 2 h 05 min on the ground at Dubai, then DXB–SYD departing 02:15 local with a block time of 13 h 30 min. On 9 July the UK is on BST (UTC+1), Dubai is UTC+4 and Sydney is on AEST (UTC+10). The airline's minimum connecting time at Dubai for international-to-international transfers is 60 minutes. The client wants to know exactly when they land, how long they will actually be travelling, what happens if the first flight runs late, and why a later Sydney–Los Angeles flight seems to land before it takes off.
1. Calculate the local arrival time and date in Sydney and the total elapsed journey time from the LHR departure to the SYD arrival.
Read the worked answer
Convert everything to UTC first - never add local times directly.
| Leg | Local | UTC |
|---|---|---|
| LHR departure | 14:20 Wed 9 Jul (BST, UTC+1) | 13:20 Wed 9 Jul |
| + 6 h 50 min flying | - | 20:10 Wed 9 Jul |
| DXB arrival | 20:10 + 4 = 00:10 Thu 10 Jul | 20:10 Wed |
| + 2 h 05 min connection | - | 22:15 Wed 9 Jul |
| DXB departure | 22:15 + 4 = 02:15 Thu 10 Jul | 22:15 Wed |
| + 13 h 30 min flying | - | 11:45 Thu 10 Jul |
| SYD arrival | 11:45 + 10 = 21:45 Thu 10 Jul | 11:45 Thu |
Elapsed journey time: 13:20 Wed → 11:45 Thu UTC = 24 h 00 min − 1 h 35 min = 22 h 25 min.
Sanity checks worth doing out loud for the client: Dubai is only 3 hours ahead of London, so 00:10 feels plausible; Sydney is 9 hours ahead of London, so a 21:45 evening arrival after a 14:20 departure is right. Always state the date as well as the time - the connection crosses midnight locally in Dubai.
2. The LHR flight pushes back 2 h 10 min late. Using the same block times and the 60-minute MCT, does the Dubai connection hold? Show the arithmetic and state what the agent should do.
Read the worked answer
Recalculate: departure 16:30 BST = 15:30 UTC. Arrival at Dubai = 15:30 + 6:50 = 22:20 UTC = 02:20 local on Thursday.
The onward flight is scheduled to leave at 02:15 local. The passenger arrives five minutes after the onward aircraft has departed. The connection does not hold - and note that the MCT is not even the binding constraint: a 60-minute MCT would require arrival by 01:15 local, so the itinerary fails on both tests.
Agent actions, in order:
- If both sectors are on one ticket, protection and rebooking are the carrier's obligation - contact the airline (or the handling agent) for the next available Dubai–Sydney seat and have the ticket revalidated/endorsed in writing.
- If they are on two separate tickets, the second sector is at risk of being a no-show. Warn the client immediately in writing, and ask the carrier whether a goodwill rebooking is possible.
- Check whether the ticket contains more than one sector on the same contract: a long final arrival delay from a single booking may trigger fixed compensation under the applicable passenger-rights regime (UK/EC 261-type rules) - quantify the delay at Sydney before advising the client, and do not promise compensation.
- Confirm hotel/meal entitlement depends on the cause of the delay and the carrier's conditions; get the rebooking confirmed before the client flies.
3. On the return, the client flies SYD–LAX departing 10:00 on Friday 18 July, block time 13 h 30 min. Los Angeles is on PDT (UTC−7). Give the arrival time and explain to the client why it appears to land before it departs.
Read the worked answer
Calculation: 10:00 AEST (UTC+10) = 00:00 UTC on Friday 18 July. Add 13 h 30 min = 13:30 UTC on 18 July. Convert to PDT: 13:30 − 7 = 06:30 local on Friday 18 July.
So the flight departs 10:00 and arrives 06:30 on the same calendar day - it looks as though it lands 3 h 30 min before it left.
Why: two effects work in the same direction. First, the aircraft flies eastbound across the International Date Line, which steps the calendar back one day; second, Los Angeles is 17 hours behind Sydney, so local clock time is gained. Neither effect changes the real elapsed time - the passenger is still in the air for 13 h 30 min.
How to explain it: "You lose a day going east and gain one coming back west." Give the client the UTC elapsed time alongside the local times on every itinerary so the calendar shift is never a surprise - it matters for hotel check-in (their room is booked for the night of the 18th, and they arrive in the morning) and for any onward connection.