Fbm3rd From United States of America, joined Mar 2005, 162 posts, RR: 0 Posted (9 years 5 months 1 week 6 hours ago) and read 5619 times:
So this may be a simple question that has been asked/answered before (i did a search, but didnt see much)
Using DEN as an example, what happens to all the planes that were due into DEN over the past few days? It is clear that the canceled flights departing DEN are stuck, but what about the hundreds of planes that were to arrive into DEN. Are those planes just sitting at their original departing airports? I'm sure airlines need those planes so what do they do?
BlueFlyer From Tuvalu, joined Jan 2006, 4939 posts, RR: 3
Reply 1, posted (9 years 5 months 1 week 5 hours ago) and read 5567 times:
Generally speaking, the planes unable to fly to DEN can and do replace the planes unable to fly from DEN, but efficiently managing a fleet of airliners is very complex to a point that there are about as many answers as airlines with planes stranded in DEN. Here are a few examples to give you an idea.
BA had a plane stuck in DEN overnight on Wednesday. The Thursday flight ex LHR was canceled and instead, the plane that would have flown LHR - DEN can now fly whatever route the plane stuck in DEN was supposed to have operated if it had come back on time.
UA serves ELP from DEN exclusively. If UA has a plane stuck in ELP and it's not absolutely needed elsewhere, it'll stay in ELP until flights to DEN resume. Otherwise, a ferry flight will be set up to take it where it needs to be.
WN's flight 2984 is DEN LAS LAX, but the plane is stuck in DEN. WN can use one of its planes in LAS that were intended to go to DEN to operate the LAS LAX leg of flight 2984 instead.
UA flies to BOI from DEN, SFO and LAX (mainline). It may very well have a plane stuck in BOI that was intended for DEN, and a normal schedule for both SFO and LAX. Rather than leave a plane sitting unused on the ground for an extended period of time, the idle plane may be inserted into the LAX BOI LAX rotation so that the plane arriving from LAX will not turn around and head back out immediately, but will leave that to the plane originally bound for DEN and will operate the next BOI LAX flight instead, forcing the next incoming LAX BOI plane to sit that one out and spend some time on the ground too. Bottom line, UA will have a plane on the ground at BOI, but not the same one for an extended period of time.
8C flies SJC DEN TOL and return nightly for BAX. This particular case is probably the easiest one to solve. For the duration of the airport closure, the flight becomes SJC TOL and return.
[Edited 2006-12-22 08:50:02]
When we unleash the dogs of war we must go where they take us
9252fly From Canada, joined Sep 2005, 1427 posts, RR: 0
Reply 4, posted (9 years 5 months 5 days 13 hours ago) and read 4938 times:
Most of you would find it very interesting watching an operations manager juggle aircraft when things start to unravel. The best analogy that I can think of is a clown juggling a lot of balls at once and then someone else suddenly adding or removing a ball or more depending on how extreme a scenario you want to use.
Tcfc424 From United States of America, joined Nov 2003, 540 posts, RR: 2
Reply 5, posted (9 years 5 months 5 days 8 hours ago) and read 4783 times:
From a laymans point of view, as I have no knowledge of actual airport ops, it really depends on the route, its frequency and its usage. If it is not stuck in the affected area, it will generally overfly the stop and continue on its normal routing. If it is scheduled to RON and is not stuck, it may RON at the previous stop or continue on to the next stop to RON and to be in position for the next day's schedule. If it is an exclusive route (i.e. UA ELP-DEN) then the aircraft may stay at ELP or be ferried to the next destination for the a/c.
Essentially, the ops personnel have severe heartburn and probably consume massive amounts of coffee. Aircraft are often utilized 10-14, sometime up to 16 hours a day, so when 1 aircraft goes down (i.e. stuck in the snow) it could affect several stops.
I don't know how many WN a/c were stuck in DEN (I think OPNL said 2-3) but considering a lot of their aircraft fly 4-6 legs per days, that could affect a ton of flying. Taking the high number of six legs a day, three a/c grounded for 2 days would affect 36 flights...at 100 pax per flight, that is 3600 pax....
I don't claim to be an expert, not am I, but that is what I am led to believe is the case. I am sure one of the ops people could fill in more detail...after a well deserved rest...
DxBrian From United States of America, joined Mar 2006, 135 posts, RR: 0
Reply 6, posted (9 years 5 months 4 days 14 hours ago) and read 4564 times:
There is a lot more to this puzzle than just the airplanes. We are long past the days when a crew that flew the plane into a city flies that same plane out, if that airline has multiple arrivals and departures at that airport. There is software to optimize airplane usage(block hours per day), and software to optimize crew utilization to meet that aircraft usage. Most airlines would have both types of this software. There are also programs to assist in irregular operations. There are so many variables in this type of situation that just affected DEN, it's scary.
A large part of it depends on the airlines and city involved. There are varying levels of problems depending on the size of the airline, whether the city in question is a crew and aircraft base, how your aircraft are scheduled, how the crews are scheduled, and on and on.
Obviously, airlines like Frontier will have a different scale of problems than United, American or Continental due to the size of the airline. United has a significant presence in Denver, their problems were/and still are a different order of magnitude from the other legacy carriers based on where this happened.
I will use these past difficulties at DEN to illustrate some of the problems, which can become exponential. I am not currently an employee of any of these airlines, though I did work for Continental Micronesia for over 6 years.
In order to keep the first scenario as easy as possible, we will assume all Frontier Airlines aircraft and crew routings begin and end in Denver. If Denver is closed due to snow, in this scenario no Frontier Airlines aircraft will be moving, as they can't leave Denver and they can't arrive in Denver.
I will use Continental Airlines to illustrate the second scenario as I am somewhat familiar with their Operations Control System, however the aircraft routings and crew routings I will use are not necessarily representative of Continental's current operations. In this scenario, you are a passenger booked from ORF-EWR-SFO. Most likely, the aircraft, pilots and flight attendants overnighted in ORF, so the first leg is not a problem. Your first leg is on a B737, and operates on schedule. The EWR-SFO leg is on a B757, and the aircraft supposed to operate that leg is in Denver. Your cockpit crew flies in from CLE, and the flight attendants from various cities. Now the fun begins, is there a B757 available in EWR to operate the EWR-SFO leg? If you're real lucky, the canceled EWR-DEN flight was a B757 and you're home free. If it was a B767, you're probably still in pretty good shape as the crews are cross-qualified, but what if it's a B737. You're probably set for cockpit crew and flight attendants, but a lot of passengers are not going to get on the flight.
Multiply that across all the connections available on the network carriers, and you can see what I mean about the problems becoming exponential. One advantage to their size is they can afford software to optimize their aircraft and crew routing to recover from these situations, where smaller airlines will be scuffling and brainstorming for solutions. There may be software available for smaller airlines, but a case would have to be made to spend the money when it could be used elsewhere.