I hate waiting in line, even for a minute.
This post expands upon a great post in The Operations Room blog on passport/immigration waiting times at Heathrow. The queues to clear passport control at Heathrow have become quite political (see this article). The reason is that the UK have increased security (read: slower server service rates) and are anticipating a large number of new passengers when they host the Olympics this summer (read: larger customers arrival rate).
I had the misfortune to travel to and from London via Heathrow in mid-April. (London was a pleasure, the queue at Heathrow was a misfortune). It took me nearly two hours to get through immigration. I had plenty of time to think about queuing and logistics while I waited. Here are some of my observations.
- There were two large queues: one for EU residents and one for the rest of us. The wait at Heathrow was much shorter for EU residents. Residents should have a shorter wait. The Operations Room notes that the goal is to get EU residents through the queue in 25 minutes and non-EU residents through in 90 minutes.
- The problem at Heathrow was staffing too few people. There were 3-6 booths open for non-EU residents at any given time. They could have maxed out to ~15 booths. There were two people at the front of the queue that would tell us when a booth became available.
- My service time was about 30 seconds, but 15 seconds to walk over to the booth. Some of the open booths were a long walk from the front of the queue. There wasn’t much inefficiency in the system except for the long walks to open booths.
- The system is not at steady state. International arrivals come in bunches. It was very busy when I arrived at immigration and less so later. This makes it challenging to staff the booths. If you are a passenger, your wait is a bit of the luck of the draw. If you arrive at the wrong time, you may have to wait for awhile. Clearly, scheduling >6 people to work the non-EU booths is a bare minimum. I’m not sure if it was possible. One cranky member of the Heathrow staff was unsympathetic because she claimed to have been working for 14 hours at that point.
How could queue waits become shorter? It’s easy: open more booths! In reality, that may be easier said than done: manpower was recently reduced by 18%. Here are some other suggestions.
- Having an “on deck” area near each immigration booth where the next person in line could wait would eliminate most of the walking time from the front of the queue to the booth (15 seconds per passenger). The walking time was large relative to the service time, since most service times are short.
- Some passengers, however, require a long service time. The problem with an “on deck” area is that passengers would get irate if they get stuck behind someone who takes a long time. It’s all about managing expectations.
- Heathrow in particular needs to find the right mix of staff in the booths vs. directing queue traffic. For the Olympics, it’s probably a good idea to have lots of people directing traffic since they’ll have fewer passengers who are familiar with the airport. People in the UK do this very well, so I expect that those who come for the Olympics will not be lost in the airport.
- When I entered the queue, there was a sign that said “45 minute wait from here.” The sign was clearly bogus, since it depends on how many booths were open. My wait was more than an hour longer than the posted sign. I would recommend against signs that raise service expectations. People will get even more impatient if they are promised a shorter wait.
- Centralized immigration booths are efficient (if run properly!). Therefore, I would advise against something like mobile agents who could do the passport checks at the gates. This would only introduce new inefficiencies. The agents would need extra time to move from gate to gate and then set up. Passengers may view a less efficient mobile agent system as “fair” or “preferable” since they are first-come-first-serve and they have shorter lines. But I’m not so sure about this.
- When all else fails, they can take a cue from Disney and install video projectors where they can show Beatles footage and play famous movies set in London. Or if they can’t find the overhead to install new equipment, they could hire street performers like jugglers to perform for those waiting in line (although I’m not sure if there will be enough room for juggling).
Do you fantasize about optimizing queues while waiting in a queue?
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