Originally Posted by
FFMAN
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As well as lack of staff, the security system itself is partly the problem. Instead of the old system where one person is processed at a time (in / out and gone) the system of having your search belongings separated slows things down dramatically. Here's what happens: you arrive at a loading point - you are one of four at each station. The other three are your 'competitors' . You pick a tray, load it and then wait for a gap to put it on the belt. And wait.... because the belt has stopped loading (see later). This slows you down because you can't pick up another tray until the previous one can be pushed through. So you wait some more. I would guess that the average number of trays per pax is three so multiply that delay by three.
Also at this point the insistence on putting carry on bags into a tray is just nonsense - I have noticed a number of foreign airports have tried this and now stopped it - Dublin being the most recent.
So through the actual body scan - no problems there. Now to the other delay at the other end. Since your three trays have been loaded separately at the front end, they come out with other people's trays mixed among them. Your first tray may be three trays in front of the second and so on. I have been counting this recently to prove my point. My last time through T1 Security A - my third tray came 16 trays after the second one (although I accept that was extreme). So again you wait. If just one tray of the average three is redirected for a manual search, the other two often remain on the belt until the search is done.This causes the belt at the delivery end to back up, causing it to stop and stopping the front belt - therefore causing further delays at the front end (see earlier).
The single loading system used at Frankfurt works properly since none of the above problems occur - you load all your trays sequentially - the result being there are rarely any security queues at an airport almost 3 time the size of MAN. Average wait at FRA is less than 5 mins I would say.
I can only suggest to the frequent flyers who are frustrated that they complain to the airlines and tell them about it.
MAN management will not listen to or care about pax but they might listen to airlines.
The 4 at a time method should be much faster per lane, overall, than the one at a time, at least in theory. The reason is simple queuing theory and first-in-first out (FIFO) dispatch stacks. If you have a system that can process an item every 4 seconds that costs a lot of money to install and operate you want to keep it full the entire time. If you have a single dispatch stack that can add an item to be processed every 4 seconds with no uncertainty, then it works well. The moment that goes above 4 seconds you get dead time. Further if you have high variability in the latency and throughput at the top end you get lots of wasted time. In Manchester I have seen people spend over a minute preparing their bags and such at the front of the queue, as one-in-one out would be frozen for the entirety of the time. With 4 dispatch queues no one delay stops the system. The problem is that the items go through in an order nearly the reverse of how you want them received. Your laptop, belt, liquids, etc often go through first and your bag last. This means that you cannot clear all of your stuff until the last tray comes through, another classic queuing issue. The secondary screening situation is somewhat independent of the dispatch method as people tend to leave their stuff while waiting for the items that needs to be checked. This is often the main bag.
The thing I have noticed flying in an out of lots of places is the traveler mix can have a significant impact on the time it takes to go through security. People that fly more often tend to be a lot faster than people that fly less often, independent of what type of trip they are on. When I traveled multiple times a month for work I was much more efficient at passing through security than I am now, when I travel much less. MAN has a fairly high percentage of travellers who do so once or twice a year, or even less often. They tend to reduce the throughput of the security process. Where MAG makes this worse is they have a very high hourly vs 2-hourly capacity in there departure declarations, all around 60%. This means that they are planning for security and such to be more congested in each part of the moving window. Other leisure heavy airports, e.g. LGW and STN, tend to be lower ~55%. Since delays are a marginal effect these extra passengers can have a huge impact on the wait times. Unfortunately, it is not really possible to easily add lanes to the security system, though the lower level T1 security is a definite exception. However, they could staff more lanes in many hours to reduce the backlogs.
As for the trays for your bags, this has to do with associating images with bags for secondary screening. Again, it should make it quicker to identify and find the offending item in the bag and minimise the amount of searching and re-screening.
As a side question, when you go through security how many trays do you typically end up using? It would be interesting to see what the averages are at different airports.