Saturday, 30 May 2009

Ops secret text messaging

Here's a brief insight into the 'secret world' of airline operations and text messaging.

Working for a company that represents and handles airlines at our station, we are obliged to send short text messages to the airlines operations department and other companies that may need to be notified updating them on the progress, or slow-gress of the flight.

Consider a flight for example that departs from my station. Once airborne, we must send a message to the airline HQ as well as the handling company at the destination airport(s) notifying them of the aircraft's departure times, estimated arrival time at destination, and any other significant information such as passengers that require special assistance. The airline HQ receives these messages and it acts as a voiceless method of being able to track their aircraft in real time. Similarly, the workers at the destination airport now know an arrival time for the aircraft and can plan accordingly, so they are ready for its arrival. These types of messages are known as MoVemenT messages, or MVT messages. We send one for every flight we handle, using a specific (primative, but functional) network that we're all connected to.

When the aircraft arrives downroute, the station will send a message back to us and also to the airline's ops department, detailing its touchdown time and on-blocks time. This lets both parties know that the aircraft has arrived safely. These messages are known as Arrival messages.

There are endless other types of messages we use; some are just variations on the message and others are more specific to the loading of the flight. Load Distribution Messages, or LDM are sent in a similar manner. These messages explain how the aircraft has been loaded, such as how much cargo and baggage is onboard, and how its distributed within the holds. These are particularly necessary for multi-stop flights, so we know in advance where the cargo and bags that need offloaded at our station, are located in the holds.

LDMs must be sent before the aircraft is due to arrive down route. Obviously it wouldn't be much use sending a LDM after the aircraft arrives, as we'd have already opened it up and started looking for our cargo and bags. In most instances, LDMs are sent automatically even before aircraft departure, once the flight has been finalised or closed.

Another variation of a LDM is a CPM, or Container/Pallet distributon Message. These are more common with larger, widebody or cargo aircraft. It lists the positions of each ULD or pallet in the holds, together with what's loaded into it, such as cargo, baggage, crew bags or simply empty.

All these messages are sent via a network called SITA, many will be aware of it or even use it and others will have at least heard of it. If you don't fit into either group, fear not, as you aren't missing out on much! Messages sent via SITA are charged for, and usually by the number of characters. As such, all the messages have a strict format of abbreviations and codes that look like random numbers and letters and mean very little to the untrained eye. They take time to get used to, but after that reading them becomes second nature. I can read MVTs, LDMs or CPMS much quicker than I can read some silly text message from a friend using 'txt sp8k.

So there you have it, a quick insight into the voice-less exchange of information between many parties in the airline industry.

Sunday, 3 May 2009

Too late for check-in?

Fear not, Dispatcher is alive and well. I took some time off work to pursue other projects, and also to recharge my batteries before the summer season kicks in, I can almost smell it now. The stress, the sweat, the jet fuel, the passengers trying to smoke on the ramp, the arguments... As I expected, nothing has changed in the time I have been away. The crew still look the same, there were no A380 diversions and 787s still haven't appeared. None the less, I have missed it, and I'm grateful for being able to say such a thing. I like to get a vacation as much as the next guy but work is fun and it's good to get back. Now to the more serious issue of blogging!

Following on from a previous post about information sometimes lacking when it comes to delays, and how passengers can feel out of the information loop, I thought I might also cover another scenario in order to inform what is actually going on.

It's common knowledge that check-in closes at a particular time depending on the flight and airline. Some flights may close at STD - 40mins, -30mins, -20mins etc and with good reason. By closing check-in at a suitable time, it should provide enough time for the passengers to pass through the airport to the appropriate gate, maybe even taking in the shops on the way. But behind the scenes it also allows their bags to be screened by security, transported and loaded onto the aircraft in time, and for the paperwork such as passenger manifests and weight and balance sheets to be completed in ample time before departure.

Sometimes this check-in closure time can be a bit more flexible, and we can extend it in some circumstances. If flights are running late, we can often allow passengers to check-in at a time after check-in should have closed, should they have been held up. Because the flight is late, we still deem there to be sufficient time for you to make it to the aircraft without causing any further delay. Unfortunately, due to Murphy's Law the chances are that when you're running late and need to make that flight for an important meeting or family reunion, that we're unable to accommodate you. I'm afraid it's not us being awkward or spiteful, but luck isn't on your side today and we don't feel we could get you on the flight without delaying it.

If a passenger turns up late, pleading to get on the flight we'll do our best to help. The staff will phone or radio through to myself or someone else aircraft side to check on the progress, and whether it's too late to accept the passenger for the flight or not. Rest assured, we do have a heart and a conscience so won't automatically say no each time, however, we do have get the aircraft away on time.

If you have baggage to check it, there's a high chance we'll refuse. It only takes a few seconds to place a bag in the hold, but first it has to pass through the network of conveyor belts behind check-in, be screened by security and find it's way into the baggage make-up area. From there, it has to be transported by the ramp guys to the aircraft and loaded. If the holds are already closed, that would mean re-opening them, placing loading equipment back at the aircraft to get it on board, all costing valuable time.

We'd also have to wait for you to be make your way from the check-in area, through security to the gate areas. Assuming the usual queues at security, and the size of airports, it's almost certainly going to take you more than a few minutes. Remember, we usually assume it'll take you around 20 minutes to 'drift' through to the gate area.

The paperwork regarding the aircraft weight and balance has probably already been completed. If another person is travelling, it will have to be amended. It can be easily changed, but has to be accurate. Most weight and balance sheets I use have a small section entitled 'LMC' for Last Minute Changes. It's used for late off or on-loading of cargo and passengers. For larger aircraft, an extra 76kg for a passenger won't make much of a difference, but for smaller aircraft that are more trim sensitive, it can present a headache. It also starts to look messy as you amend it to onload an extra passenger and bag which then fail to turn up at the aircraft in time and have to be taken off again.

Hopefully that provides a little insight to why sometimes we can and sometimes we cannot accept you after the usual cut-off point.