Winter Flight Delays and YOU.


The news media covers the weather-induced flight delays relentlessly from the outside viewpoint, posing as a passenger would, facing headline-grabbing (isn’t that their stock in trade?) shipwreck-castaway-snowmageddon-apocalyptic disaster. They play it as if everything should operate normally, snow or no.

Fine–enjoy the hype, especially from the outside of the aviation profession, from the perspective of urban legend, unreasonable expectations (sure, airlines should operate like clockwork regardless of polar temperatures and contaminated surfaces) and shrieking sensationalism.


But here’s the inside look at the very real challenges, risks, and safety constraints the news media doesn’t want you to consider.

First, you personally, as an airline pilot and captain, hate the news of a winter storm.  Because of the flight delays? Cancellations? No–it’s simpler than that: just getting to the airport is a challenge on iced-over roads, never mind getting home twelve hours later–barring cancellations–when the roads are even worse.

Put that out of your mind, and leave an hour earlier for the ice-afflicted slide to the airport, adding to what you already know will be a twelve hour day. Park the car facing south, at least, hoping the north wind will coat only the back window with an inch of ice to scrape off after midnight when or if you manage to transit 3,000 air miles and return. Fat chance–on the ice, and the return.

ice car

Finally in Flight Ops, where Defcon 3 reigns: they’re almost out of standby flight attendants to assign to flights in place of delayed or diverted inbound cabin crews. Now they’re breaking up enroute or just arriving crews and reassigning them to outbound departures.

Which means, as the day goes on, more cut-and-paste flights and assignments for more crew members. That recital your kid’s in tonight? Birthday, anniversary, or just plain day off? Fugghedaboudit–you’re going elsewhere, with an indeterminate return time or even day.


Your jet is coming in from South America where it’s summer, so no problem, right?

Wrong: it will still be delayed, metered in with all arriving flow times, and summer aside, the jet will need to be de-iced anyway: the on-board fuel has been cold-soaked at altitude to about minus 30 degrees, and when that cold-soaked wing hits the moisture laden winter overcast and precip, there will be plenty of ice, especially on taxi in and after parking. Add another 45 minutes, at least, to your flight day.

And you know that de-ice is anything but simple. First, all jet intakes and cowls must be clean and uncontaminated BEFORE you even get to the de-icing pad prior to take off. Who certifies that?

Uh, YOU: get outside and stick your head into both engine inlets to be sure they’re clean. If not, add another 45 minutes to get the engines de-iced so you can taxi to get the aircraft de-iced. And get back downstairs afterward to be sure the procedure was done properly before you try to start one of those $5 million dollar engines.


The rate of precip is specified in the official weather report, but official weather reports are hourly, and we live (and answer for) the effects in real-time: YOU determine the precip rate and type (snow, freezing rain, ice pellets) and decide which de-ice procedure and fluid will be required.

Then, assuming you have made your way from the gate to the de-icing pad, YOU determine the “holdover time,” or effectiveness time for the de-icing, which again depends on the conditions (temp, precip, rate of precip) so YOU can determine how long you can wait for take off and still have an uncontaminated airfoil.


Now, consider the surface, both taxiways and runways. All takeoff performance is based on a dry or wet runway, but iciness throws in a curve ball. You have to account for the drag of slush on acceleration, plus the loss of brake effectiveness on any icy runway.

Once again, the field weather report contains the “official report,” but “official reports” don’t fly airplanes, and they are hourly, not instantaneous. You know the limits (slush, snow and ice maximums) as well as your jet’s tolerance and required corrections to your performance data.

Do the calculations for all possibilities: based on the official report, based on what you see, based on conditions worsening. Know all three and be prepared to execute accordingly.

Know that cold-soaked engines behave differently, oil and hydraulic fluids need time and circulation to achieve design viscosity. Be alert for binding flight controls, before and even after de-icing, where melted ice can trickle into dry bay areas and refreeze quickly.


Taxi gingerly, knowing that iced taxiways are inconsistently slick and your eighty ton tricycle will not stop if one side has traction but the other wheels five yards away do not. Probe the turns with the nosewheel first before you commit the main gear in a turn.

Run up both engines periodically to 70% to verify proper operation, carefully, so as not to blow away a smaller jet behind you, and with consideration for the traction as you do.

Trust but verify: as you taxi, see what’s actually happening on the runway. Is it uniformly clear? Is it draining? Are other jets kicking up rooster tails from their nosewheel on takeoff roll, indicating pooling? Are there contaminated areas? How does the last third look, given that in an abort you’ll need full braking there? How does the first third look, since you’re primary and critical acceleration will be there?


Taxi out with flaps retracted so as not to get slush or ice sprayed up under the wing and onto the flaps–they may jam on retraction because of the close tolerances, and will take extra de-ice time if they’re contaminated.

When you FINALLY taxi out, get ready for de-ice: engines shut down, bleed air from the APU off; ground crew on headset tells you the de-ice fluid mix (or asks you what type you need), then certifies afterward that the jet is clean and you start your holdover clock based on what you have determined is the max time (usually minutes) to wait for takeoff (that’s why de-icing is normally done at the runway rather than the gate).

Now restart engines, reconfigure with flaps and slats, check flight controls, final weights, final speeds, final corrections based on NOW (your three pre-calculated options) and your go/no-go decision.

Power control is key to airspeed.

Take the runway, hold the brakes, power to 80% and scrutinize all the instruments: go.

Climb out is a relief, at least partially: you still have to turn around at the coast, then fly back into the snowed-in airport after enduring even more inbound metering delays.

But the worst, ultimately, is yet to come: the drive home, if and when you return, once you thaw out your car. That, however, is 3,000 miles from now. Worry about that then, get home as best you can–with this weather, they’re going to need you to fly tomorrow, too.

Actual photo from my 2.5 hour, 30 mile drive home from DFW after a recent winter storm.

Actual photo from my 2.5 hour, 30 mile drive home from DFW after a recent winter storm.


59 Responses to “Winter Flight Delays and YOU.”

  1. I had the impression Texas was an almost tropical state, lots of sun, cabriolet cars and bbq’s….

    • Usually, it is. Which may be why when we get an inch of snow, everybody loses their mind, no one slows down on the highway and there are miles-long pile ups, the airport staff throws up their hands and ignores the snowy-icy taxiways and runways, and passengers flock to the airport regardless, like lemmings to the sea.

      It’s ugly. Can’t wait for spring …

  2. I once was on a plane that went through the de-icing procedure three times. Every time it would be our turn to take off too much ice had accumulated–and this was MSP! I can’t even imagine what it must be like in warmer places with more ice than snow. BTW, we never did take off, the flight was cancelled (fine with me!)

  3. Tini von Allwoerden Says:

    Thank you for this. Very impressive but scary. How do you cope with all that stress ?

  4. Cedarglen Says:

    I can understand why you welcome spring. I think you’ll enjoy retirement as well. In my micro climate, the forecasts are a joke as I live nearly 1K Ft. about the ZIP-coded forecast. The ‘driveway is > 0.25 mile and one must consider the AOA. In short, I knew the storm was coming last Wednesday and laid in a few veggies. Today (Sunday) is the first opportunity to get off my mountain, but no harm done as I HAD to be nowhere. You’ll be there soon! Of note: Coastal Western Oregon truly is mostly rain. We get one or two snow events per season. After the December storm it stayed cold for a week, so I was under house arrest for eleven days. This time it w as warm and wet after the 11″ stopped falling so the arrest was only 3.5 days. Safety alone, on the surface or in the air, often says “Just say ‘no,'” and stay home! A great report, Chris. Thank you. -C.

    • A perfect metaphor: went to the stables yesterday and the horses hadn’t been out for three days due to weather. Never seen such a stampede–literally–as they were sent out into the pasture stall by stall.

      I really need spring.

    • If you want an accurate temp forecast, just check the 850 mb level. That should be about right for your altitude. 🙂

      • @Peggy. Thanks. I’m not an expert in reading those things, but I can learn. An excellent point. -C.

  5. Randy Sohn Says:

    Ho-boy, BT-DT, you tell it like it really is/was! No wonder I always say “it’s good to be retired”.

  6. AA Retired Says:

    Thanks Chris,

    Another reminder that retirement really is great! What was that other phrase that accompanies days like this? You usually see it after landing at someplace you don’t want to be, when you’re trying to get your next legs flight plan. “Flight departed.” Followed by “Sequence fails continuity.” Hang in there.

  7. Winter travel–blech!

    Thank you for your post, Chris. I echo your…uh… “love” for the winter season, especially if it starts sometime in the fall. 🙂

  8. Great post but some of use are lucky enough to live near a rapid transit station so the train speeds us past all those cars stuck in traffic 🙂 Anyways de-icing is serious stuff and I remember ramp training where the crew chief pretty much began the class by bringing up a few crashes that was caused by icing to drive home the importance of a deicer’s job to those who never worked in the aviation industry before, the second topic he heavily emphasized was to avoid APU damage by applying the fluid on the tail with surgical precision if the pilots refused to start an engine at the gate. The CRJ-700’s and ERJ-145’s APU inlet was just below the vertical stab which made it easy to flood and a buddy from my class almost toasted an APU on his first plane without a trainer in the bucket but do to my former airline’s aging equipment the deicing bid was a junior bid so there were plenty of new hires vs APU battles.

    • Standard operating procedure for de-icing calls for both engines to be shut down for safety’s sake. You won’t “toast” the APU with de-ice fluid, the problem is that unless the bleed air intake is closed (a cockpit switch) de-icing fluid may get into the APU and cause smoke in the cabin afterward. The preventive procedure is to keep that bleed air switch off during de-icing and for one minute afterward. Much safer for the de-ice crew if the engines are shut down, but sometimes an aircraft has an inoperative APU and only then is an engine left running during de-icing.

      • Our crew chief told us that if we flooded that inlet the first sign of an APU failure would be a really loud pop followed by prayers for a really good union rep if you are still on probation. I’m not sure how sensitive the 737’s units are but I’m guessing the RJ’s are a bit more sensitive to fluid ingestion, and as for the safety aspect all of our planes at the time were T-tailed with engine high above us so there was little to no danger of getting sucked in (ramp crew waits in the break room until we were finished anyways), not sure if the policy changed with the arrival of the E170’s. Despite all the negative sides deicing was one of my favorite bids and it beats tossing bags any day of the week.

      • From a pilot standpoint the risk of FOD damage to a running engine is a major concern, and anyone or any thing–like a deicing boom–operating near engine inlets or exhaust is a hazard, which is why standard operating procedure for jets–T-tail or otherwise–is engines shut down during deicing.

    • I guess each airline has their own SOP’s, my comments are probably not relevant anymore since its been almost 2 years since I’ve tossed a bag or shot type II/IV fluid.

  9. Regarding de-icing….That made me wonder as well. Is it the standard procedure in the USA to shut down all engines during deicing? During my 25 years of flying the European winters deicing is either at the gate before engine start-up or near the runway with both engines running. We switch off the airconditioning to prevent the fluid fumes to enter the cabin.

    • We sometimes de-ice at the gate if there’s no precip or further icing conditions, making the holdover time a non-issue. Otherwise, at places like DFW, JFK, ORD, YYZ, taxi out would eat up most of the holdover time so de-icing is done near the departure runway. The SOP is engines off, unless of course you have an APU inop. YYZ does the best job: a drive-thru “car wash” type de-ice is super efficient!

  10. This is another reason why pilots get paid the big bucks…

  11. Pilots do NOT get paid the big bucks. I wish you could be paid as well as sports athletes, you do a far more important job.

    Looks like live animals were left out on the tarmac. True?

  12. Wow that’s a LOT of snow :O

  13. Nice to hear the other side. I’m sitting at home stuck while I should be away on a business trip. Second consecutive trip that’s been lost due to weather and flight cancellations in the past month. Rebooking is next to impossible with the full planes. I’m frustrated at the industry changes that have created this mess, but thanks to your blog I see that passengers aren’t the only ones suffering during these challenging situations. Congratulations on Freshly Pressed!

    • Thanks for reading JetHead! You are sensible to stay home, given as you noted the inability of the air travel system to re-accommodate passengers from a cancelled flight in a timely manner.

      The airport situation is a lot like the Atlanta roads during the recent ice storm: people just won’t accept that they can’t travel, even though it’s clearly not possible. Abandoned vehicles, stranded passengers–the smart ones are those who stayed home and accepted the reality that sometimes, due to severe weather, you just can’t travel.

      • Chris, sometimes it’s just about timing.

        I left North Atlanta at 12:15 that afternoon, made my way East on 285, then took 85 North to Raleigh. Six hours later, I had traveled 400 miles and was at RDU turning in my rental. One of my colleagues, who left the same location in North Atlanta to catch a flight at Hartsfield, had made it a total of 6 miles (3 out, 3 back) to wind up spending the night in the office. He had left all of 20 minutes later than I did.

  14. Nice post captain. An informative insight into winter ops. Always enjoy hearing these kind of details.

  15. Great job ! Thanks for sharing.

  16. Byron Audler Says:

    Good to hear from a commercial aviation professional on the challenges of safely operating aircraft with passengers. I’ll be tossing this up on my FB feed, I’m sure a lot of people I know (and who travel) would appreciate a behind-the-scenes explanation of all the challenges facing not only the flight deck but the cabin personnel as well. Thanks, Captain!!

  17. Thanks yet again, Chris. I’ve just been through the remaining comments and, in large part they are almost as informative as is your original post. Despite you occasional (great) humor, this is a space of learning. The posts are informative, the comments informed and the idiots extremely few. That’s why I keep coming back and thank you for some many great lessons from your side of that vault door. This blog is easily worth my time. Best regards, -C.

  18. Reblogged this on peterquianson and commented:
    Really dangerous

  19. Great Post thanks for sharing it with us all being an aviation nut I really did enjoy it..

  20. Great description of what winter looks like at the airport! Interesting that you didn’t really even get into the air traffic control (ATC) complications. Will spring never come this year??

    • I guess the issue isn’t so much “winter weather” for ATC as much as just weather delays. Those delays from the ATC standpoint have nothing to do with icing, de-icing or runway contamination, although clearing runways may cause some delays. ATC weather delays normally are due to low ceiling and visibility (a weather problem year-round) and winds.

  21. Aww…an this year’s been particularly bad on the snow front. Hope they go away soon..

  22. MichaelMilano Says:

    I guess, my car wouldn’t open is a small problem when comparing to this…

  23. A sobering read, especially since I’m reading this while waiting on a delayed flight.

  24. Very well written. Sure glad I don’t have your job!

  25. At least you operate from a semi-civilized airport.
    I was once delayed for 4 hours at TAB waiting for the deicing truck (they had lent it to POS)

    Thanks for the insider’s perspective, a refreshing – no, make that freezing – change.

  26. elliott001 Says:

    At least you can function a little bit over there with snow. 1 snowflake and the whole of London shuts down completely!

  27. I am very scared that the Malaysia 777 has had a bomb go off or some catastrophic failure. No Pan call, just disappears at 35,000 feet. Weather seemed fine. I thought the 777 has a good safety record? Just read about 2 passengers using stolen passports. Some think the problem could be similar to Air France flight 447. I don’t agree with that theory.

    • I don’t see the Air France scenario happening on a Boeing either. Guess we’ll have to wait for more information. It took a couple years, but we eventually got answers from the Air France jet even though it was on the bottom of the ocean. I’m sure there will eventually be a cause determination.

      But I trust Boeing aircraft engineering and workmanship 110% and stake my life on it every single day of my career.

  28. Cedarglen Says:

    Hi Chris,
    It seems that we have not heard from you – for a bit too long. I hope that you have a new post in process. They are always great reading. Thanks, -C.

    • I am, but there’s kind of a gridlock–midterm for my two university classes (I’m down to 32 students–this semester has taken its toll), plus my own research, plus flying 95 hours/month.

      But I have a draft in progress–stand by …

  29. As an airline pilot, I relate to everything you described — except one thing. You actually get to do one-day trips? Sweet! Try parking your car in an outside lot at O’Hare for SIX days, covering the span of three snowstorms, during which time the snow on your car has compacted, melted, re-frozen, and been snowed on again multiple times. Now you return, bedraggled and tired from almost a week of backside-of-the-clock flying in foreign lands, only to find that your car is now a large block of dirty ice with an antenna sticking out of it. It is minus 10 degrees, and the wind is blowing 30 knots. Your bottle of ice-melt is inside the car, and since TSA doesn’t allow you to carry tools or sharp objects, you have nothing that even resembles a windshield scraper. You are wearing your thin poly/cotton uniform and back dress shoes. GO! 😉

    I enjoy your writing. Thanks!

  30. Wow! Thank you for this article! Everyone needs the truth instead of the aviation’s largest hide and seek game with a 777.

  31. I am that lemming and “I quite thank you for an uncompromising view of airfoil.”

  32. Reblogged this on Stay in touch and commented:
    Just remember these days…

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