Saturday, September 27, 2008

How to Turn Around a B767

From the tiny to the giant. After the time it took to refuel the ultralight at every stop, I was intrigued by this website, optimizing the efficiency of block in to block out of a Boeing 767. It shows how different services are required by a large passenger airplane and how to best arrange the servicing vehicles to access the various orifices on the airplane.

I like the project management bar graphs showing the time required and available for each service. They take into account details like the fact that some last minute baggage may be thrown on while the main baggage conveyor is being put away. There are also very detailed tables showing the airflow rate required from ground carts for pneumatic engine start at different air temperatures and altitudes, and the requirements for ground towing vehicles. The latter is as complex as a take-off performance chase chart, with reference lines and slopes to follow for aircraft weight, traction wheel load, engine thrust resistance (even at idle the engine is resisting a backwards push), and seven different surface conditions, from dry concrete to ice.

You know how hot a car is when you return to it on a hot day. The usual technique is to open all the windows so the really hot air can escape before blasting the air conditioner. The problem with the hot vehicle scales up, but the doors on a Boeing are pretty small and only the front windows open, so the solution doesn't. There are tables here showing how long to expect it to take to cool (or heat) an airplane using ground services.

If makes sense that aircraft designers and airline planners put thought and effort into the efficiency of the turnaround, because the incredible speed of an airplane can easily be wasted waiting for the right things to be loaded and unloaded on the ground.

9 comments:

Colin Summers said...

It's not just losing the time. The plane only makes money while it is in the air, so a quick turn is money. Southwest did away with reserved seating for this reason. It shaved twenty minutes off the boarding time. At Burbank (and possibly elsewhere) they board from the front AND the back, speeding up the loading (JetBlue does this in Long Beach).

John said...

The quickest turn of an airplane Ive ever seen has been a minute or two tops. It wasn't an airliner but a Learjet carrying organs. They just stop one engine, open the door, hand out the cooler, shut the door and they are off. Nothing at all like that but I did carry a human heart in a cooler once.

Dispatcher said...

As someone responsible for the said turnaround, the complexity at times is overwhelming and totally agrees up with the whole chain analogy with each link as important as the next and I'm the last link bearing the load (aircraft/captain) who has to explain why it hasn't left already! There is endless teamwork involved from multiple companies all with their own schedules that have to come together. From the minute the aircraft arrives on stand my head is a tangled mess of objectives that all need to be achieved to a tight schedule and straightened out. Correct loading/unloading, safe boarding and disembarkation, fuelling, catering, cleaning, waste removal, engineering, endless company specific policies to adhere to... Paperwork! On average one of my flights has about 7ft of paper for the passenger manifest and loadsheet alone, each of which is 3-ply so there's 21ft of paper without even including the the NOTAMs, WX Charts, plates, Plogs... Remember the old 'When the weight of the paper equals the weight of the plane...'

There's good days and bad days, but you take the good with the bad and smile as you finally push the aircraft back off stand and the captain is happy to call it off blocks on time. Only then does your mind relax for a second as you think a job well done but back to work, there are wingtips to watch and engines to smell as they start up. Beats a proper job!!


Keep meaning to start my own blog about it but never get round to it. I find the pilots' blogs fascinating, maybe one from the ground ops side of things as a further insight.

PS Keep the posts coming! I love the technical detail you go into

Aluwings said...

Hey Dispatcher - I for one would love to read some of the stories of life from your perspective. I hope you get around to it!

Aviatrix said...

Or, Dispatcher, if you don't want to do a whole blog of your own but have a few stories or procedures you want to explain, I'd be happy to have you guest-blog here, and I bet Aluwings would too, on his blog.

Dispatcher said...

If there's some interest then I shall see what stories I can write up from happenings in work. Though it is dispatch as in the UK term for it rather than the Canadian/American licenced dispatcher. The equivalent of your team leader/turnaround co-ordinator I think.

dpierce said...

I love this stuff. One of my favorite childhood toys was a JAL airport set that featured a 747 and a fleet of little service vehicles that attached to the plane like so many nursing piglets. It's too bad it didn't come with any miniature luggage for the tractor to run over.

Dispatcher -- I'd certainly read. Logistics rule. I had a British customer give me grief for spelling "dispatch" with an "i" as you spell it. I was told that was the "American" spelling!

Buffadog said...

My company has spent a lot of time looking at and anlysing aircraft turnaround processes and how to improve/automate them, we are a combination of ex-Disptchers, airline ops and IT people and have developed a handheld turnaround tool to help dispatchers manage the complexities of aircraft turnarounds whilst saving time, fuel and cost for the airlines. (www.avtura.com) I'd be happy to add some stories about aircraft dispatch to any blog that Dispatcher gets up and running.

traveller42 said...

I had to wait for a military charter in St. Louis for a few hours. I was quite impressed with the processing of flights by the Southwest ground crew. There was even one point where they backed a plane straight back; docked an incoming flight; unloaded, loaded, and launched the new plane; re-docked the first plane; loaded and launched the original plane.

The fastest turns I ever participated as part of the ground crew was at a dirt strip during a field exercise downloading and uploading a C-130. We took the existing load off and loaded the waiting load with a total ground time of less than 5 minutes. This is from the cargo ramp at the rear of the aircraft with flying dust, engine exhaust and the 82nd Airborne adding to the difficulty factor.