I know I'm not very smart, so can someone tell me why, if they are aware the flight will be delayed, they don't announce the delay before boarding? Seems like the fine only kicks in when the passengers are effectively imprisoned in the aircraft for absurdly long periods.
We do announce delays. If the delay is known before departure time, we do announce the delay. There is no purpose served in not announcing the delay. Known delays include such things as weather, late arriving aircraft, late crew, mechanical issues, security problems at the airport, and a delay in getting fuel to the aircraft.
The only time that people are "imprisoned in the aircraft for absurdly long periods" is when unforeseen circumstances arise that are beyond control of the airline. That doesn't happen very often. Normally, all the participants (FAA, ATC, airline, pilots, gate agents, flight attendants, ground crew, etc) can predict delays due to weather, traffic congestion, and other issues. Sometimes, delays happen regardless of preparation.
Since New York's JFK is infamous for delays, I'll use them as an example. I've actually experienced this scenario at JFK, but it is combined with another experience I had at BOS.
APS Airways flight 1911 to Los Angeles is at the gate after having all the customers boarded on time and the flight is ready for pushback. There are no delays known to the APS captain, the APS dispatcher, or to ATC. So, the flight leaves the gate on time.
Just an aside, but an on-time departure is when the parking break is released before scheduled departure time, which means the flight has "blocked out," not when the plane takes off.
Back to the story... So, the flight leaves on time from the gate and gets clearance to taxi to runway 13R at JFK. Now, this time of day at JFK is very busy. There is a large international flight push, as well as lots of domestic traffic. The airline flight schedulers know this is a busy time of day, as do the dispatcher and pilots, so everyone is prepared for a long taxi. The flight block time is padded to deal with the predicted long taxi, so the flight doesn't routinely arrive late. Normally, this works out well and the flight arrives on time, which is defined by the DOT as within 14 minutes of scheduled arrival time.
So, the plane taxis out towards runway 13R at JFK. After getting in the congo line, the pilots determine that the taxi time to the runway before they get to takeoff is 1 hour. All is normal. About 30 minutes into the taxi, a small front that has been approaching the airport causes the wind to shift enough that runway 13R is no longer useable for takeoff. Now, runway 31L (the opposite end of the same pavement) must be used. So, ground control at JFK freezes all ground movement so they can turn the airport around. While ground control is working on that, the tower is trying to land a bunch of planes before the runway switch happens. During this process, 30 minutes elapse.
APS 1911 has been off the gate for 1 hour, but is still 30 minutes from takeoff.
Meanwhile, the captain and first officer are watching their fuel quantity burn down knowing that they have a minimum takeoff amount that they are getting close to. As APS1911 approaches the runway, a CompeteAir flight needs to return to the gate due to a mechanical issue, but because of taxiway congestion, the CompeteAir flight can't really move out of the way which causes more delays for everyone at JFK.
Finally, after 2 hours from leaving the gate, APS1911 is first in line for takeoff. They have enough fuel, both engines are running and all is right. Until ATC stops all departures. No one knows why just yet, as the controllers at JFK aren't volunteering any information.
15 minutes pass.
The JFK controllers announce that all west bound traffic is stopped due to a radar outage in Denver center. So, since APS1911 is not going anywhere, but is blocking access to the runway, they must be resequenced along with others into the taxi line.
2 hours 15 minutes have passed since leaving the gate.
After resequencing, APS1911 is once again 30 minutes from takeoff, if they are allowed to go when their turn comes up. So, that means that they can take off 2 hours and 45 minutes after leaving the gate, if nothing else changes. Now they are starting to worry about fuel, the 3 hour rule, duty time, gate availablity in JFK should they need to go back, the customers in the plane who are beyond antsy, etc.
The flight crew has been communicating with the gate crew at JFK attempting to get gate space to return to if needed, but none is available due to other aircraft returning to the gates and aircraft that are prevented from leaving the gates due to the now known delays. A gate will be vailable in 30 minutes.
So, they stay in line hoping to depart before three hours pass.
At block out +2:58, APS1911 is once again first in line and ready for takeoff. JFK tower says "APS1911, expect a 5 minute delay due to spacing on your route." Uh-oh. That means the flight must return to the gate, by law, to allow customers to deplane. That will also mean the flight will be put in the back of the line when it comes back out, and the plane will need to be refueled. A long enough delay could mean that the pilots are no longer legal to complete the trip.
So, as the captain of APS1911 what would you do? If you were in charge of cancelling the APS flight what would you do? If you were a customer on the flight what would you want to happen?
I know it sounds far fetched, but I've done it several times.
(edited for clarity)
