CX flyboy From Hong Kong, joined Dec 1999, 6805 posts, RR: 55
Reply 1, posted (11 years 10 months 3 weeks 4 days ago) and read 3248 times:
A rough plan of aircraft assignments is often drawn up by major airlines 4-5 months in advance of the flight actually happening. Of course, there are lots of changes happening all the time, so an aircraft assigned to a flight a few months in advance could well be on a different flight, but having the plan helps the airline figure out how many spare aircraft they have, and whether there is an opportunity for extra flights etc...
How much havoc is caused really depends on the airline. When fleet utilisation is high and there are few spare planes on very tight schedules, one aircraft being taken out of service for unscheduled maintenance could cause delays for a few days. On the other end of the scale, when there are spare aircraft, it is possible that only that one flight is delayed, if the aircraft is taken out of maintenance at short notice, and it there is more time, perhaps no delay at all.
OPNLguy From , joined Dec 1969, posts, RR:
Reply 2, posted (11 years 10 months 3 weeks 4 days ago) and read 3218 times:
Here is the US, specific aircraft (tail number) assignments are made within a few -days- of actual operation, 3-5 at my airline. The main driver for routings is to get aircraft overnighted at specific places (with maintenance facilities) at specific dates so regular MX work can be performed during the overnight hours.
When an aircraft goes out of service unexpectedly during the day, it can cause things to get scambled, the severity of which depends upon the nature of the breakdown, the fix, and whether parts and company MX personnel happen to be at the same airport where the breakdown occurred. Often times, they are not. Contract MX folks might come out and troubleshoot the problem, then parts (and maybe our own personnel) will ride out on another flight to actually fix the aircraft. In some cases, parts might be borrowed from another airline, and/or the contract MX folks might do the actual installation. As usual, lots of variables...
If an aircraft was scheduled to start the day at "ABC" and end up at "XYZ" for overnight MX work, and breaks down somewhere in between during the day, our office will figure out another way to get it to someplace where the MX work can be accomplished, once the cause of the breakdown is remedied..
AAR90 From United States of America, joined Jan 2000, 3582 posts, RR: 44
Reply 4, posted (11 years 10 months 3 weeks 3 days 2 hours ago) and read 2998 times:
1) how far in advance are specific aircraft assigned (in this case AA)
Usually 2-6 days in advance of an actual flight. Most "long-range" planning is done for aircraft that require a specific routing (i.e. to get to a maintenance station), future routing(s) and equipment pairings. For example, mid-day flights are usually planned well in advance since the aircraft assigned to that flight will probably be continuing onto another flight. OTOH, mid-late afternoon flights are often assigned based upon where the plane will be at the start of the next day's flying (or maintenance required, etc.).
2) how much havoc is caused by an aircraft being taken out of service
At AA, anywhere from a minor hick-up to a major, full-blown headache. It all depends upon the type aircraft, location, time-of-day, number of pax/cargo, future flights, crew availability, etc., etc., etc.
*NO CARRIER* -- A Naval Aviator's worst nightmare!
Whiskeyflyer From Ireland, joined May 2002, 224 posts, RR: 0
Reply 5, posted (11 years 10 months 3 weeks 2 days 17 hours ago) and read 2941 times:
how much havoc is caused by an aircraft being taken out of service
Well part of our business is having an aircraft on standby for high utilisation airlines. Within one hour we have the aircraft, crew, fuel ready for them to fly their passengers. They pay us a retaining fee.
Another interesting factor is competition on the route. Where lots of competition, delays (be it mechanical, ATC) are very bad for the airline's image, so they like to have a standby aircraft.
Where no competition, passengers it appears can just wait.