Apart from sharing an Atlantic flight with a screaming infant, there’s nothing more frustrating than being trapped in a cramped aluminum tube for hours–and going nowhere. Worse still, for shorter commuter flights, it only needs a 90 minute delay and it would’ve been quicker to drive.

Recently, there have been high-profile cases of passengers being stuck on board for several hours. In August 2009, 47 Continental passengers were forced to remain on their jet overnight after it diverted to a regional airport. It seems that the duty manager refused disembarkation because security staff had gone home. Whilst these marathons are quite rare – for now – some airlines have seen the litigation on the wall and done something about it.

In 2007, Jet Blue published a ‘Bill of Rights’ after passengers endured up to 11 hours on their aircraft, unable to disembark. There have been shorter hijackings! With this Bill, passengers are assured compensation. Even so, the trigger point at which the airline actually guarantees to deplane is an amazing 5 hours. With a decent tailwind, that’s the flight time from Boston to London.

So, what are the main reasons for tarmac delays?

Firstly, it’s necessary to understand airline policy. In most cases, they will board even if they know of a delay in advance. Larger aircraft take over 30 minutes to get passengers into the right seats, by which time any potential improvement will have been missed. There’ll be an inbound flight needing the gate as well, so the best place for the delayed plane is on a taxiway, ready to go.

‘Avoidable’ Tarmac Delays:
Although there’s an argument that tarmac delays are unavoidable by their very nature–no airport makes a plane sit there for the fun of it–a bit of common sense could have made all the difference. Take the Continental example above. The passengers weren’t going anywhere until the airport reopened, so why not let them wait in the terminal?

Air Traffic Controllers do an excellent job, but are often let down by their tools. Certain airports operate a ‘slot’ system, where peak hours are divided into timeslots, then allocated to airlines. There’s little flexibility allowed for, and a few minutes’ delay early on can snowball into hours for later flights.

Sometimes ATC is its own worst enemy, too. In June 2000, a new UK airspace system went live one day, and dead the next. The back-up system was paper strips, something designed decades previously, and massive delays were inevitable.

One more ‘avoidable’ cause is the technical delay. Obviously, airlines cannot predict exactly when a part will fail, and would be negligent to depart with a defect. However, if they haven’t the spares available then the delay can be substantial, especially if a part needs to be flown in from the airline’s main base.

Unavoidable Tarmac Delays:
ATC can be responsible for a delay even when they’re doing an excellent job. They occasionally have in-flight emergencies where a stricken aircraft needs to land immediately. In such cases, a runway will be made sterile–closed to all traffic so that nothing can block it. And if that was an active take-off runway…

A more common situation is where a nearby airport has been forced to close. Diverted airplanes will be low on fuel and, unless the diversion airport has several runways, take-offs will be curtailed. Add to this all those planes sitting on the ground that should be somewhere else, and the knock-on effect is enormous.

And so to the big one. Weather.

With her thunderstorms, wind shear, fog, snow and hail, Mother Nature clearly hates the aviation industry. Commercial pilots never willingly fly into hazardous weather conditions, and a big thunderstorm can close even major airports. It’s obvious to those waiting in the pouring rain what the problem is. But passengers 500 miles away, whose flight is sitting in blazing sunshine, might just think they’re being lied to when weather is quoted as the cause.

With passenger numbers increasing, and the airways becoming more and more congested, one thing is certain. Tarmac delays are here to stay.

This entry was posted on Friday, September 4th, 2009 at 7:59 pm and is filed under Airlines, Phillip Clark. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.