(I have never seen a faked mechanical. I strongly disagree with the assertion that any mechanical is faked. Completion percentage is a huge measure of how the airline is operating, and every effort is made to complete every flight on the flight schedule. The goal is always 100% completion. It's silly to suggest that on a light day the airline might only want to complete 95% for the day, and save a few bucks. Doesn't happen.......)

Hmmm, I'd say accurate on the pilot's side however.... I was on a flight where the pilot announced loud and clear on the plane an apology (for a VERY late take off) because he turned back to EWR for mechanical (fuel gauge) reasons. On the other hand Continental told all passengers it was because of weather, and offered nothing! It was a total nightmare of a flight.

During my nonrev days, an operations person told me that airlines would sometimes take turns cancelling flights in certain circumstances.

Here's an example: in the NYC-CHI market, airline A and airline B each have an evening (last flight of the day). On a given day, both flights are less than 30 percent full.

The next morning, both airlines have early morning flights that return from CHI to NYC, and both of those flights are very lightly booked as well.

Therefore, airline A cancels its evening NYC-CHI flight and also cancels the return CHI-NYC flight the next morning. Airline A's passengers are protected on airline B's flight in both cases.

What's the benefit to airline B? The next time the same circumstances occur, the airlines reverse roles.

Again, I have no idea it it was true, but the employee swore it was true.

I'm sitting in ORD right now, and the 10:00 a.m. to MSP (NW 131) is "cancelled due to aircraft maintenance." I got here at 7:15 a.m., and that flight was already listed as cancelled, nearly three (3) hours prior to departure. It could've been more.

But when you realize that 10:00 a.m. is a mid-day, off-peak kind of time, I wouldn't be surprised if it were lightly loaded.

btw, weather is clear here in ORD, and no ATC issues, so they had to make it a mechancial cxl.

I used to work at the OMA at a rental counter. Working the evening shift...I can tell you, some airlines have an awful lot of "mechanical" problems on some of their flights. One example that comes to mind was the *rontier airlines (the name has been changed to protect the guilty) flight DEN-OMA, which at the time was scheduled to arrive in OMA around 2000 hours. The aircraft would then return to DEN and end its day in OMA later that night (around 2345 hours). Many many evenings the 2000 arrival was cancelled due to "mechanical" problems with the aircraft. We used to joke that the plane was "too light to fly", so they "fixed" it by adding passengers on the late flight! Lots of biz pax on that earlier flight called it "rolling the dice" on getting to OMA at 2000 hours vs 2345 hours!

Airlines like about this kind of thing all the time. I've been on flights that left late due to a late-arriving crew. The late departure made most connecting passengers misconnect. Said flights were then further delayed by weather. CO called these delays "weather related" and denied comepsation (hotel, etc.) to the misconects who were stuck at EWR for the night.

I had the chance to spend a day in System Ops at NW with a dispatcher. He let me know many of the ins and outs of keeping a very large airline running efficiently.

Often times if there is a mechanical, crew shortage, or other valid reason a flight can't get out, they may swap planes with another flight that has similar equipment, but low loads in order to inconvienece as few people as possible and keep "the system" running smoothly. He said that a hiccup in the system can reverberate for days. So what looks like a cancellation for low loads, can only be called so in a very qualified sense.

the-ca-goat, I agree that dispatchers of course want the greatest good for the greatest number, and the least disruption and cost to airline and passengers. So cancelling low-load flights seems the right thing to do, if flights need to be cancelled at all.

But, the question is whether airlines might also cancel flights just to save money. Cancel one round-trip a day on an overserved city-pair, and avoid paying the crew and fuel expenses for that segment.

In post #30 above, I suggested one way to test this: To the extent that cancellations are due to weather, we should see that more cancellations (of the overserved markets) occur on bad weather days.

How can we show that cancellations aren't due to genuine equipment problems, on other routes, for which the overserved route equipment gets used as the spare? I still don't know.

We should be able to tell whether cancellations happen more at the end of the month, though. If end-of-month is associated with crews being close to their flight limits (after which they have to be paid more, etc.), then dispatchers would want to cancel more flights at the end of the month. And month-ends are exogenous -- random, with respect to weather and equipment problems -- such that we'd have a pretty convincing result (showing airlines' "bad" behavior) if we found more cancelled flights near the end of each month.

In the UA Shuttle days flights between LAX & SFO were running hourly, even 1/2 hourly during peak times. Dozens of cancellations were the order of a typical week. I can't help to think that here and there a flight inbetween with light loads was cancelled and folks just rolled over to the next flight, 30 or 60 mins. later.

I had my share of rollovers in those days - many due operational delays of that UA flight concept at the time.

It is not uncommon for some airlines to be loose with the truth on these issues. I've seen/heard it with my own eyes/ears!

I guess there is an equity or fairness argument mixed in with this. If you are on a moderately loaded flight that is moving along just fine, and at another gate a flight to a crowded city has a mechanical delay, is it OK for the airline to swap planes and call your delay a "mechanical?"

I don't mean "CAN they do it" or if it is in the "contract of carriage." Instead, I wonder if it is right?

You are in a movie theater at a cineplex. The more popular movie next door has the projector bulb burn out. The usher comes in and tells you all to leave so they can show the other movie in your theater.

It would be unthinkable, even though the inconvenience would be FAR less than the plight of the displaced passengers.

At the least, the airline should have to say something like "we are cancelling your flight because we have decided to use your intended plane for another flight that had it's plane scrubbed due to mechanical. So we are transferring their mechanical delay to you so they can leave. Sorry."

Dick.....you're right!! NW has this NASTY habit of cancelling MSP-SNA & ONT flights, putting everybody on the LAX flight, and giving everyone taxi vouchers to their home airport. The "mechanical" is always on another aircraft slated for a different city, but when MSP is short one Airbus, the SNA & ONT guys get the shaft. This was told to me by a senior MSP "ops" manager!! Pretty sad........