July 13, 2012
Have you ever been on a delayed flight and had the crew come on the PA and say they would try to make up some of the time in the air? Unless your flight is over six hours, there’s usually not much they can do to shave off more than a couple of minutes. I recently heard this promise from a crew on the short flight from Washington D.C. to New York. This is a flight that’s already in the 40 minute range, give or take a couple of minutes, and it’s nearly impossible to improve on it — especially when you factor in the vectoring required during the approach phase of the flight.
Last night I was scheduled to fly the red-eye from Las Vegas to New York, and we were delayed about an hour because our plane was late getting in. I was at the departure gate before the plane showed up, and a few passengers came up to ask if we would be able to make up some of the time in the air. I took a look at our flight plan, and saw a flight time of 4:03. That’s pretty good for this flight; my personal best for that route is 3:56, and usually it falls in the 4:15 to 4:40 range, depending on winds aloft.
Looking deeper into the flight plan, I noticed that our dispatcher had used a Cost Index (CI) of 999, which is the max. This is a number we put into the Flight Management Computer, and it determines the power settings and airspeeds to be used throughout the flight. If we’re on time and the winds are extremely favorable, the CI might be set to zero, giving us maximum fuel efficiency since an on-time or early arrival is virtually assured. With the 999 setting, the company had decided that we would sacrifice fuel economy to make up as much time as possible and maybe get some passengers to their connecting flights in New York. The difference between these two settings on a flight of this length is probably around 10-15 minutes, but at the expense of a lot of extra fuel burn for the shorter flight.
After seeing the high CI, I explained to the passengers who were interested that we were already planning for the quickest flight possible, and wouldn’t be able to improve on it. We could ask for a direct routing once airborne, and at this time of night we’d probably get approval to fly directly to Wilkes-Barre, Pennsylvania once we were handed off to Los Angeles Center. This sounds great, but the net savings for this trans-con flight is just a few minutes.
I try to avoid promising any time gains because there are so many variables that can make a liar out of me. On this flight, for example, we encountered greater than usual delays in the approach due to a temporary closure of one of the arrival runways. A landing aircraft had hit a bird when touching down, and they closed that runway while a ground vehicle did an inspection. This backed us up and probably added 10-15 minutes to our flight time — much more than any savings we got from direct routing or the higher cost index.
May 2, 2011
Air traffic controllers have been in the news several times in the past month. First came the “asleep in the tower” stories at Washington National Airport and Reno, Nevada. Then the First Lady’s airplane had to go around at Andrews AFB because it was too close to other traffic. The 24-hour news monster has already moved on to the next “shiny object” (the Royal wedding), but I thought I’d share my thoughts anyway.
I was as surprised as anyone about the traffic controllers; I always assumed there was more than one guy in the tower at all times. Still, the comments I heard from the pundits on TV and radio had me shaking my head. There seemed to be a worry that pilots had to land without the security blanket of ATC, and I heard the phrase “landing blind” more than once.
The tower controller (aka Local Control) has jurisdiction over the runways at the airport. He or she clears planes to take off, land or cross any active runway. It’s important, especially at busy airports, but there are hundreds of airports in the country that are not served by a control tower, and pilots manage to sequence themselves for takeoff and landing just fine. In the wee hours (the period during which the DC and Reno controllers were asleep), there is very little traffic, and the danger posed by “do it yourself” is minimal.
At uncontrolled fields, pilots approaching the airport announce their position and intentions on a VHF frequency set aside for that purpose. It might be a Unicom frequency serving several small airports in the area, or a specific frequency for that airport called a CTAF (Common Traffic Advisory Frequency). The airlines don’t fly into many uncontrolled fields, but they do exist. When I worked for United Express, two uncontrolled fields I routinely flew into were State College, Pennsylvania and Shenandoah Valley Regional airport in Virginia.
I’m not trying to minimize the seriousness of falling asleep at the switch, but it just wasn’t as dire or life-threatening as some reports led you to believe.
The second story was even less serious, and shouldn’t even have made the news. Michelle Obama was on a plane coming into Andrews AFB, just outside Washington, and had to execute a go-around because her plane was too close to the plane in front of it.
First of all, “too close” doesn’t mean there was danger of them exchanging paint. It just means that someone was concerned that the first plane wouldn’t be clear of the runway before the second plane touched down. The rule is only one plane on the runway at a time.
I would be surprised if you could find any pilot who hasn’t had to go around at some point. It doesn’t happen to the airlines very often (or to planes carrying the First Lady, I’m sure) because the controllers and the pilots try hard to avoid it. But it does happen every day, at airports all across the country.
There are a few possible scenarios that typically lead to a go-around. The first is when the controller is a little overzealous in trying to squeeze in arrivals. I’ve seen it on a handful of occasions where a controller, trying to keep the arrival rate up, vectors a plane in too close behind another one. Again, not dangerously close, but close enough that it becomes obvious at some point that it’s just not going to work out. Result: go around.
Other times, it’s strictly the pilot’s fault. A controller will often point out preceding traffic to us, and if we call it in sight we are likely to receive the following clearance: “Maintain visual separation from that traffic, cleared for the visual approach to Runway 31L.” If we accept that clearance, the burden is now on us to maintain adequate distance from the preceding plane so that it can land and clear the runway before we touch down. If we get too close, the controller will tell us to go around.
The pilot of the first plane can also mess things up by slowing unexpectedly during the approach. At busy airports, the controller issues exact speeds for the planes to maintain, and anyone who deviates from these speeds can ruin the flow. The approach clearance will often contain a final speed restriction, like “Cleared for the visual approach to three one left, maintain a hundred eighty knots to MEALS.” (MEALS is an intersection 5.4 miles from the end of the runway at JFK airport.) Occasionally we’ll get someone who slows to final approach speed too early, and, you guessed it: another go-around for the following traffic.
The last possibility is that the preceding traffic just doesn’t clear the runway expeditiously. At busy airports, the controllers are very sharp, and they expect the pilots to be on their game too. They know our capabilities and how much runway we need to land, slow and exit the runway. Occasionally a pilot surprises them by rolling out to the end of the runway, throwing a wrench in the beautiful arrival flow the controller has established. Some unlucky innocent on final approach has to go around.
I don’t know what happened with Mrs. Obama’s plane, but I’m pretty sure she was safe the whole time. A go-around is inconvenient, but it’s also routine.
November 18, 2010
I just had a nice stretch of days off and went on a five-day golf trip with my brother and 30 other guys. It was a little chilly on Amelia Island and I performed about like you’d expect a 15 handicapper to play. But it’s not the golf that I want to talk about. Instead, I want to address a common misconception that the public has about airlines and their schedules.
When I arrived at the Jacksonville airport, one of my fellow golfers related his experience flying in that morning. Seems that his flight had fewer than 20 passengers booked on it. He told his buddy, “You watch. They’ll cancel this flight.”
Sure enough, about 15 minutes after his prediction it was announced that the flight was canceled due to a problem with the hydraulic system. He rolled his eyes as he told this part of the story. As far as he was concerned, the “hydraulic problem” was an obvious ruse by the airline to avoid a money-losing flight.
I tried to set him straight on this, but I could tell that there was no way I could convince him that we don’t cancel flights because of light loads. There’s a good reason for this: It’s because that plane is supposed to get somewhere to make another flight, and then another one after that.
I’ve flown for two airlines, and not once did I have a flight canceled because of a light load. In fact, I’ve had several flights where the crew outnumbered the passengers. I remember having three passengers from LGA to DCA on an MD-88. We had two pilots and three flight attendants on board (one per passenger…pretty good ratio for them!)