Destination Weather: Do You Feel Lucky Today, Punk?


I have one eye on the fuel flow, the other on my watch: the two are inextricably linked with the only variable being the rate of consumption. Always have hated math, especially in a situation like this where the stubborn numbers refuse to add up as I’d like them to do. We have only so much fuel and therefore only so much time, with the factors of altitude and speed governing the number of minutes till we fall out of the sky.

It’s a major factor because DFW is experiencing the fallout of a normal summer weather pattern: storms.

Here’s where we can often expect a call from the back. “The guy in 4B says his office emailed him and the weather’s fine at the airport.”

Of course, the flight attendant’s call isn’t to pass along the special knowledge Mr. 4B’s office has forwarded (busted! we’re holding for the fun of it) but rather to give us a laugh while also letting us know that the typically self-righteous know-it-all’s are being themselves which is to say, a pain in the ass.

Air Traffic Control radar display

Because actually, the weather at the airport is clear, as is the weather between us and the airport. But the weather ninety miles beyond the airport is blocking the aircraft from the other coast from arriving–so where might they go?

Bingo! To our arrival corner post! That is, if the two corner posts–mandatory overfly points that sequence the arrival crowd of flights into the airport–on the far side of the airport are blocked, there’s going to be a fuel-hungry crowd gathering on our side which means–everybody gets to hold. Despite what Dwight can see out the office window.

So now options are limited, but there are some choices to be made and with those choices, I cast our lot among the other fifty jets all negotiating the same decision process. First, speed: should we push forward fast and burn a lot of fuel to get to our arrival post first? That would put us at the head of the line–except for those from the far side ATC may vector in front of us. In that case, we’ll have wasted precious loiter fuel getting there fast for nothing. And it’s a long way–in distance and fuel–to our alternate.

Or–and this is what I usually prefer–we can slow down, save gas en route, maybe even stay in the high altitude sector to save even more fuel rather than enter the descending holding stack where fuel flow increases with the lower altitude and the high banked turns required to stay in the holding airspace. Then, if we must divert (I hope not) we’re closer to our alternate and will get in and out before the crowd of other diverting aircraft do the same thing.

But that option might put us too far back in line to hold until everyone else lands. Double-edged sword, this weather strategy biz. No matter what you choose, there’s a downside:  the fuel flow continues regardless and even “slowed down,” we’re rushing toward the arrival corner post at about 400 miles per hour. So the question is, do you feel lucky today, punk?

Here’s where we often get a call from the back asking if we could say anything for the Dunder-Miflin crowd second-guessing whatever decision looks best from where I sit.

But what can I say? Especially between fast-changing options: F/O is off searching for the best and lowest-fuel required alternate and weather for each, I’m doing the math with the speed and fuel flow and guesstimating how long ATC is allowing folks to stay high plus how fast and in which direction the weather is moving and on our radar, how it’s developing or decaying and at what rate. That, plus the close-fast-low or lag back-slow-high equation that’s in constant flux.

So I will make a P.A., not for the backseat drivers but just to prepare the crowd for the delay–which is all we can be sure of at the moment. Plus, it seems to me best to make no promises or predictions because I realize how frustrating it will be if after a few minutes, I have to explain why what I just related is now irrelevant. And, I need to have my attention and concentration back in the cockpit so as to not miss a single clue in the arrival puzzle that’ll get us in earlier, or any weather awareness via radar or reports from a half dozen other airfields that when put together, give me a clearer picture of our best course.

That’s what’s happening on my side of the cockpit door when you feel us slow down dramatically or even go into a series of turns that often indicates that we’re in a holding pattern. It’s that time of year again and with the ever-increasing density of arrival traffic, this scenario is going to arise often.

Maybe now you can help me out by explaining to the Dunder-Miflin guy seated next to you steaming over the delay exactly why I’m not saying much, plus what you now have a pretty good picture of up front. I’ll get to you as soon as I have a free moment and something definitive to say. Which for me would be “flight attendants, prepare for landing.”

And if I’ve been able to maximize all the variables I just described, that will be at our scheduled destination.

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5 Responses to “Destination Weather: Do You Feel Lucky Today, Punk?”

  1. Jock Bethune Says:

    Well written and informative, Chris! Thanks!! Jock

  2. tomorrowsgirls Says:

    Chris– I thought I knew something about flying (even allowing for how little I know about flying, I’m ahead of at least the one guy who observes that his pals in the office in Arlington think the weather’s fine). But as I read your posts, I realize just HOW little I know about flying commercial aircraft in the current state-of-that-art.

    Thanks for clueing we the travelling dunder miflins. I just wish you could have a weekly column in ‘Time’ or even ‘The Wallstreet Journal’ so that more of these guys (and, yeah, me too) would be exposed to life in YOUR office. 🙂

  3. It’s amazing how fluid those fuel/time calcuations are, Chris. I work the NE cornerpost at DFW. One nasty weather day, we go into holding, because of missed approaches at the airport. TRACON doesn’t want any more airplanes than necessary as long as they are milling around and not proceeding to land. So after about 20-30 minutes of holding, we start bringing them back in. One guy is on his way in, less than five miles from the post, and he declared that he needs to divert. Seemed odd to me, but perhaps he had info that his approach would be less than successful. He therefore opted to fly to OKC to wait for better conditions. It just seemed to me to be an awfully late moment to be making that decision.

    • You all do a TREMENDOUS job sequencing everyone despite weather everywhere, hundred knot tailwinds from the west (which means hundred knot GS difference from those out of the east) plus the usually heavy morning and afternoon traffic jams–I appreciate all you do!

  4. keithpeers Says:

    a great read on the weather. i always look at the aviation weather. its lots better then TV WEATHER.

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