Go or No Go: is there any way through this line?

Your 1981 Piper Aztec and you have been through a lot in 10 years and 3000 hours, including plenty of single pilot IFR trips. But today is going to be a test for both of you – your proposed trip home from Shreveport, Louisiana to Amarillo, Texas is filled with rain, low ceilings and some convective activity.

The airplane is well equipped (besides the two engines), with deice boots, dual WAAS GPSs, datalink weather and a good autopilot. It also has an on-board radar that, while older, does provide some real-time weather information. You are current and confident in the airplane, and regularly fly IFR in the Aztec. The trip should take about two and a half hours.

Here’s what you find at 20:50Z (3:50pm central time on May 13) when you fire up your iPad. Read the weather report and tell us if you would go or cancel the flight.

Overview

There’s a pretty solid line of rain stretching north to south across Texas, slicing your trip in half.

GNG main

The surface analysis shows a low pressure system to the west, with a weak warm from sagging across north Texas.

GNG surf anal

Radar and Satellite

Convective weather is obviously the key concern today, so you compare the radar overlay in ForeFlight to the raw NEXRAD image. That line looks pretty solid – are there any holes to the north of Dallas?

GNG radar TX

The infrared satellite shows relatively clear skies behind the weather in Amarillo, but there are thick and well-organized clouds across most of Texas.

GNG infra sat

The visible satellite picture shows that some of the weather south of Dallas has some noticeable vertical development.

GNG vis sate

Prog Charts

Is any of this weather going to get better? A look at the prog charts suggests that it will, but not any time soon. First, the 12-hour prog chart.

GNG 12 hour

The 24-hour chart shows the low moving off to the north, but with some lingering showers and storms throughout Texas and Oklahoma.

GNG 24 hour

AIRMETs and SIGMETs

Convective SIGMETs are out today, all around your route.

GNG convective sigmet

Next you review the AIRMETs for icing, which looks like it won’t be a big issue today – at least at your typical altitudes of 8-12,000 feet.

GNG ice airmet

Turbulence AIRMETs are all in the flight levels along your route.

GNG airmet turbulence

PIREPs

Now it’s time for a look at what other pilots are saying today. First up are the Pilot Reports for icing.

GNG pirep icing

Then it’s on to the turbulence PIREPs, which are mostly clear.

GNG turb pirep

Finally, you review the other PIREPs, which don’t add a lot of detail.

GNG pirep vis

Text Weather

The weather at your departure (KDTN) and your destination (KAMA) isn’t your primary concern, but it’s still wise to review conditions. Both are showing marginal conditions, but visibility is good.

GNG METARs

Next, you look at the Terminal Aerodrome Forecasts (TAFs), which show continuing marginal conditions.

GNG TAFs

Your Call

It’s decision time. The airplane is fueled and pulled up to the front of the FBO, and your wife is expecting you home tonight. But you’ve been flying long enough to be prepared for some bad weather, so you have an extra change of clothes in your bag. Time to load up and pick through the line of weather? Or time to find a hotel?

Add your comment below.

20 Comments

  • As a student of IFR, this sort of procedural analysis is incredibly helpful. Thanks for the post.

    Oh, and no, I’d stay at the hotel and watch cable TV snuggling up to my travel toothbrush.

  • This is not an easy flight, that’s for sure. But it’s doable for someone of this experience and with this equipment. New pilot in a 172? No way. Experienced, current pilot with datalink and on-board radar? Yes.

    I think it’s definitely safe, the question is all about comfort. Looks like you could swing around to the north a little bit, watch the on-board radar and find a spot to go through.

    Of course I used to fly freight in piston twins… In those days this was a Go – no question about it!

  • Start off with a plan to detour a little north but watch out for that gap to fill in. If it does, work on plan B.

  • I’d consider going, but I would want to see how each of these systems are moving, and if they are getting bigger, smaller or are stable. Watching the animated radar would tell me that. It may be possible to head south of course and let the nasty stuff move northward out of your way.

    Either way, I’d be sure to have datalink and the approach plates for every airport with me.

  • This looks like a trap. Having myself flown east-west through the southern Great Plains many hundreds of hours during T-storm season, I can vouch that much more often than not it ends up being worse than the NEXRAD image shows. You think you can pick your way through the “holes” that turn out to not be holes when you get there … but once there “get-there-it is” kicks in and like the little red devil sitting on your shoulder, it starts whispering in your ear “go on … no big deal you can do it!”.

    Get a room and tell your wife to expect your safe arrival sometime tomorrow after this front passes by. Perhaps it might even dissipate by later in the evening.

  • I love these real world situations. This time, it’s a well equipped Aztec, aka “Aztruck” for its ability to carry nearly anything through just about all weather and a certificated up-to-date pilot who’s likely seen lots of these kinds of situations.

    With this kind of equipment, airplane and pilot, departing and seeing how things develop during the flight seems like a good plan. There are a number of decent airports along the way and to the north – what currently looks like the best way through the weather.

    What gives me a bit of pause is that this is a warm front which can be fickle. The convective activity could dissipate, remain the same, or get a lot worse. This kind of weather situation can be very unpredictable, so being nimble in your decision making is very important.

    I’d likely file direct Lawton (LAW) direct and check the forecasts for KLAW and check the weather for Halliburton (KDUC) as well.

  • Looks like a trap ready to close to me as well. I’d wait it out if I could, or get a hotel room for another night.

  • Stay in the hotel. The flight in good weather will be safer and more enjoyable. Your wife will thank you for coming home safe–with a souvenir or some flowers.

    • Michael – very good pilot story video, on several levels including the importance of effective flight planning.

      From the perspective of weather, it illustrates not only that weather reality is often very different than both weather forecasts as well as current weather depictions (such as NEXRAD) … it also illustrates how the cockpit, in the middle of executing a flight, is not a place where the pilot is best equipped to make objective flight decisions. It is o so hard to admit “defeat” (which is how we pilots often define a flight that doesn’t end up where one planned) and divert (or simply make a “no go” pre-flight decision).

      No – once we’re in the cockpit and the mission is at risk, we tend too often to rationalize bad decisions and carry forward even though sitting in a safe spot on the surface we’d say, “that’s not a good decision”.

  • I’ve penetrated this kind of thing successfully a few times and not so successfully once. It would be fine to decide to take a look, and I’d give 2:1 odds of finding a way through, but as I approach 1,000 hours, I don’t feel the urge to prove myself so much. I’d pick the nice, comfortable hotel room.

  • Perhaps one way to look at this is: for this trip, a good outcome of making the flight is a challenging late-day, wet, IFR, and possibly rough ride; an intermediate outcome would be getting partway along, then having to land at an inconvenient place; the worst outcome is death. I would prefer the night in a hotel room after the best dinner I could find, chatting with the wife by phone, watching a bit of TV, and getting a good night’s sleep. The entire day available next morning might offer some better flight options with greater safety margins.

  • Waiting until the next day would be my choice. Frequently, these storms dissipate overnight and an early morning flight can be really pleasant.

  • I have been caught in enough bad weather to know that it is far more comfortable to go to the hotel have a couple of beers to make sure you don’t decide to launch at midnight and get up early the next morning. As the old story goes, the weather is always perfect for the accident investigation.

  • Even with a glass cockpit (G500, GNS750, GNS430, XM Weather, Foreflight Pro as backup,a good autopilot and an X500 stormscope on board, I’d use the time to catch up on reading a good book in the hotel rather than the possibility of being read about in an obituary. No question that it MAY be “doable”. But the question you have to ask yourself is, “If Scott Crossfield, a test pilot and astronaut with many thousand of hours of flying many airplanes could be killed mistakenly thinking his “experience” could get him through and yet was mashed like a ant by mother nature, what makes me think I’m going to be lucky every time I go up and my personal minimums are exceeded.” See http://en.wikipedia.org/wiki/Albert_Scott_Crossfield As a Captain and Pilot and Search Director of our local Civil Air Patrol, it only takes seeing all the blood all over the airplane wreckage to convince you that taking chances is dumb. The real issue is establishing AND FOLLOWING your own personal minimums ALL THE TIME!!!

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