NEXRAD radar
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This Go or No Go is a little different. The scenario I’ll present is an actual flight I had planned and the decision I had to make. I’ll show the weather conditions that were forecast and my plan, then I’ll let you decide if you would have flown the trip. Check back in a few days and I’ll share whether I decided go or no go.

First, the details of the trip. I was headed home to Cincinnati, OH (LUK) from Hilton Head, SC (HXD) after a family vacation. It was a Sunday afternoon, and I was anxious to get back for the work week. Unfortunately, a slow-moving low pressure system had parked itself right in my path, with an occluded front to the south and a large area of rain to the east. It was not a pretty day to fly, with lots of rain, ice and low ceilings.

Fortunately, the Pilatus PC-12 I was flying is a capable airplane. This pressurized, single-engine turboprop can climb to 28,000 ft. if needed to top weather, and is equipped with XM datalink weather, on-board radar and a complete de-ice system. In addition, I was proficient and comfortable in the airplane, as I frequently fly it on long IFR trips. Finally, I always fly with a co-pilot, so I had another set of eyes to help out.

Let’s look at the weather forecast that greeted me Sunday morning and you can decide what you would have done.

Overview

I always like to start with the big picture view, so I checked the most recent weather depiction:

US Weather Depiction, 51412

The forecast maps showed worsening conditions, if anything, as the low was forecast to slide northeastward:

12 hour prog chart

24 hour prog chart

The radar map showed solid rain, although not a lot of convective activity. It also confirmed that the area of weather was not moving very fast:

NEXRAD radar

The satellite image didn’t offer much detail, other than some hints of higher tops to the north:

Eastern US satellite

Convection

With the overall picture in mind, it was time to consider three big issues: thunderstorms, turbulence and icing. First up was a look at convective activity. The map of Convective SIGMETs showed nothing along my route of flight:

Convective SIGMET

A check of the CCFP map gave some supporting detail:

CCFP forecast

Turbulence

So far, it looked like thunderstorms weren’t going to be a major factor. But that didn’t mean the ride was going to be good, so I checked some sources to see what turbulence I might encounter. The chart of AIRMETs was pretty clear, especially up high at a typical cruise altitude for the PC-12:

PIREPs for turbulence also showed little activity:

PIREPs for turbulence

A check of the turbulence forecast from aviationweather.gov showed smooth sailing at 25,000 ft.:

Turbulence forecast at FL270

Icing

Cross turbulence off the list as a major concern. Could it be that this large weather system with all this rain really didn’t have any unpleasant flying conditions? A check of icing conditions suggested perhaps no. First the AIRMETs for ice:

Icing AIRMET

Pilot reports seem to back up the AIRMET, with reports of light and occasional moderate icing below 22,000:

Finally, the CIP/FIP forecasts show that if we could get up to FL260 or FL280, we might be above the ice. But this would most likely entail a climb through a fairly thick layer of icing clouds:

CIP FL270

The forecasts for icing severity showed that the ice was most likely to be moderate, tapering to light above 25,000 ft:

Severity at FL250

Severity FL230

Airport weather

So convection was not a major concern (although the heating of the day could change that). Turbulence didn’t look bad, either. Icing was a concern, although it looked like we could top it. Time for a review of the text weather.

Hilton Head was gusty, but showed good conditions:

KHXD 131650Z 17008G16KT 110V230 10SM SCT029 BKN080 25/18 A3020=
KHXD 131550Z 18008G16KT 120V220 10SM SCT029 BKN120 25/18 A3021=
KHXD 131450Z 19009KT 150V240 10SM SCT028 BKN038 24/19 A3021=

En route conditions were mostly marginal VFR to IFR, with light rain and mist:

KGSP 131653Z 13004KT 6SM -RA BR BKN007 BKN047 OVC060 18/17 A3020 RMK
    AO2 SLP219 P0001 T01780167=
KAVL 131654Z 15005KT 5SM -RA BR SCT010 BKN017 OVC039 16/14 A3022 RMK
    AO2 SLP221 P0001 T01560139=
KLEX 131654Z 10006KT 4SM -RA BR FEW007 SCT014 OVC090 17/16 A3013 RMK
    AO2 SLP198 P0009 T01670161=

Weather in Cincinnati was significantly worse, with mist, rain and low ceilings. But it was still well above minimums for the ILS 21L or possibly even the LOC BC 3R. The forecast was for conditions to stay the same, or possibly improve slightly:

KLUK 131653Z 00000KT 2SM RA BR BKN010 OVC015 16/14 A3017 RMK AO2 CIG
    006V012 SLP214 P0009 T01560144 $=
KLUK 131553Z 05006KT 3SM -RA BR BKN010 OVC031 16/14 A3018 RMK AO2
    SLP216 P0000 T01560144 $=
KLUK 131534Z 06007KT 3SM -RA BR BKN010 OVC033 16/14 A3018 RMK AO2 CIG
    006V014 P0000 $= (SPECI)
KLUK 131453Z 06007KT 3SM -RA BR BKN019 OVC038 16/14 A3018 RMK AO2
    SLP218 P0006 60026 T01560139 58003 $=
KLUK 131450Z 06009KT 3SM -RA BR FEW010 BKN019 OVC038 16/14 A3018 RMK
    AO2 P0006 $= (SPECI)
KLUK 131411Z 04003KT 2 1/2SM RA BR FEW006 BKN014 OVC025 16/14 A3020
    RMK AO2 P0002 $= (SPECI)
KLUK 131353Z 06004KT 2 1/2SM RA BR SCT023 BKN028 OVC033 16/14 A3020
    RMK AO2 SLP224 P0011 T01560144 $=
TAF AMD KLUK 131321Z 1313/1412 00000KT 2SM -SHRA SCT005 OVC025
     FM131500 08005KT 5SM -SHRA BR SCT005 OVC012
     FM140500 00000KT 2SM BR OVC012=

You make the decision

There’s the briefing I read as I considered my options. It wasn’t a great day, but I did have a capable airplane. One final piece of the puzzle: I had my family on board. My standards for safety don’t change, but should my standards for comfort change?

You make the call–what should I have done? Go or no go?

UPDATE 5/29/12: So what did I decide? I’m usually in the “go” camp when flying this airplane. But in the end, I chickened out and spent the night. I felt pretty confident that I could get home if I had to or if I was getting paid to do it. But I was a little nervous about some of the rain turning into thunderstorms as the heat of the day set in. Also, while it would probably be ice-free at FL270, I had no out if it wasn’t. Since the plane is not RVSM-approved, I essentially could fly at FL270 or 8,000 ft. That violates my rule about having a good out.

In any case, I want flying to be a fun part of a family vacation, not something to be endured. The next morning we had a beautiful flight home on the backside of the rain. A week later, nobody remembered getting home 12 hours late. But a bad flight that scared some passengers would be remembered forever.

John Zimmerman
23 replies
  1. Mark
    Mark says:

    NO GO! You brought your family up in a challenging flight. That tells me you are already thinking about something else other than flying. In a single engine plane, on a flight path with weather, befitting the toughest golf hole at the Masters, MY level of comfort would be pasted pegged with ALL the work you did. I have flown enough to understand the word UNFORECAST conditions and this is a set up with Ice which would put you right back in the weather. In a Twin Engine Jet (Gulfstream, B-737 etc) with a First Officer and total focus on flying, not family…different story. Ref: Scott Crossfield’s last flight in a C-182! NO GO!

  2. Scott Singletary
    Scott Singletary says:

    NO GO! A wise instructor once told me that she has a simple formula for determing a go, no go decision. (set aside for a minute the thorough weather brief, pilot capabilities, aircraft capabilities, and Federal Regulations.) If two things come up that you don’t like when planning a flight, don’t go! We all know that in many cases the accident chain is a series of seemingly minor, and often times unseen mistakes. If you take off with two things already on your mind you are already two steps behind the airplane. In this case you may already be thinking about the week ahead and relying on an uneventful climb or descent through icing conditions to transport you and your family home from a nice vacation. If I were faced with this, I believe my family and I would enjoy an extra day or two of vacation!

    • Mark
      Mark says:

      Scott, you and I will wait a day and take the family to a nice dinner tonight, and go in the morning. May get some nice scenery instead of clouds. If we just happen to loose the critical engine, we can see where to glide into for lunch.

      Gary and Alice… can eat baloney sandwiches as the ice builds up! God bless ’em!

      NICE CALL Scott!!

  3. Stephen Phoenix
    Stephen Phoenix says:

    Would you have ridden the airlines up there that day? The PC-12 is probably as capable as any commuter airline with recent flight school graduates up front. I’m guessing they weren’t cancelling.

    The airplane is capable and, if the pilot is experienced and current, there should be no reason cancel. Having family onboard shouldn’t change the comfort level since there isn’t any apparent threat that is not faced in normal cross country flights.

  4. John Latta
    John Latta says:

    NO GO. My take is slightly different. The three factors which weight against the flight are: (1) tired at the end of the day, (2)family on board (this is big) and (3) variable weather at KLUK. Rest over night and the weather was likely much improved in the AM.

  5. RIch
    RIch says:

    Go. Capable airplane, capable pilot and the only comfort factor to consider is turbulence of which there was none to worry about.

  6. Colin Smith
    Colin Smith says:

    Go. Icing is the major consideration with climb and descent through moderate ice. However, freezing level is around 8,000, so option is available to descend into warm air and continue to destination. PC-12 should be able to handle FIKI OK, though.

  7. Scott Dennstaedt
    Scott Dennstaedt says:

    First, let me suggest John that you include the valid time of the weather data. Not all of them you included had valid times on the chart or in your description. It’s hard to make a determination if you don’t know when the charts/diagram are valid. So I took a look at this flight using my own archived data.

    There was very little upper-level support with this weather system with ridge to the east of the proposed route.

    From an IFR perspective, there were plenty of fairly close alternates with clear conditions to the east or northwest of your destination. Perfect if the weather at LUK decided to drop below minimums.

    Assuming a 16Z departure, climb out to FL250 or higher should have resulted in light or negative icing. Based on the soundings, color-enhanced IR image, CIP and FIP, there should have been little or no threat of icing while en route.

    On the other hand, descent may have been the biggest issue. First, I would have filed a route through Greensboro, NC before turning to the northwest. Second, I would have asked for an early descent to get below 13,000 feet by the time I got to the Kentucky or West Virginia border. That was the weakest spot from an icing perspective. Once at or below the freezing level you’d simply be dealing with flying through light to moderate rain the rest of the way to your destination.

    Convective and non-convective turbulence was not an issue.

    One other comment John. Be careful using the CCFP for decisions like this. Unlike what most pilots are taught or perceive, it’s actually *not* a thunderstorm forecast. It has a bit different criteria than used for the issuance of convective SIGMETs and intended for a much different audience (airlines).

  8. Larry Baum
    Larry Baum says:

    John et al:

    I’ve almost always been the “go” side of these scenarios. I’ve come to realize that aircraft and pilot capability go hand in hand. That’s one reason I’ve moved “up” in aircraft capability to the Aerostar that we now own. In addition, I’ve worked very hard to maintain skills and be proficient in any airplane that I’ve owned or flown regularly.

    In the previous scenarios, I’ve carefully looked at the pilot and airplane being flown. And I’ve always thought – “This would be a piece of cake in the Aerostar”! And I’ve still come down on the “go” side having spent many years slogging through the Northeast’s IFR in all kinds of airplanes. This is the first scenario where the plane (PC-12) is more capable than our Aerostar. (OK, I’m officially jealous, but would probably pick the TBM 850 for its higher performance and my loads aren’t that big…at least I can dream a bit!)

    Back to this flight: John, I share your sentiment regarding safety. Having the family on board has NEVER been part of my go or no-go decision making as far as safety goes. Comfort does count, but on this flight, there’s not a lot of comfort concerns. It’s IFR, definitely a bunch of IMC, but likely little turbulence.

    In the PC-12, this is under a two hour ride. I presume you’re going to carry lots of fuel. Enough to deviate significantly to the Northeast or overfly KLUK if the weather goes south there and get on the backside of the coldfront.

    In our Aerostar, I’d probably have to head more northeast because we could fly no higher than FL240, which might not top the weather. So, I’d be looking the forecasts that way and possibly crossing the front further to the east and then swinging back to KLUK on the backside of the front. Slogging through this in a non-pressurized aircraft would give me pause. Probably wouldn’t do it.

    Bottom line – in a high capability aircraft with a proficient pilot, it’s a go with careful planning and reasonable outs.

  9. Pick
    Pick says:

    Can only think of one thing to add to the decision to go. In this plane, with its capabilities and range, looks as if there are lots of alternatives. Certainly looks as if you can launch… and the worse that happens is that you don’t end up where you planned and have another dinner out and another night in a hotel… which is what you’ll have if you don’t try. And you’ll be that much closer tomorrow morning.

    • John
      John says:

      except your family may give you sizeable grief when you wait an hour at xyz airport for a car and you stay in bug infested motel 4 in bfe… family is a huge consideration here. good choice John. hopefully you kept your job despite arriving late.

  10. Pick
    Pick says:

    In twentybfive years of flying all over US, don’t remember any bug infested hotels. Not always five star but if you’re going to bail and go to an alternate can pick one near a decent size city.

  11. Steve Phoenix
    Steve Phoenix says:

    Well, can’t be critical of the decision; you had a good flight the next day and everyone had a good time. So that works.

    When I make those decisions I always find myself asking the next day; geeze, why didn’t I just drive the minivan? A lot cheaper and I would have gotten home as planned. But then, of course, the minivan doesn’t fly so maybe that’s the answer.

  12. Larryo
    Larryo says:

    I’m certainly in the camp that this would be a routine flight and certainly a go, for a good plane and a competent pilot. I will not second guess another’s “comfort” zone, so there’s little downside in canceling, excepting getting home a day late, and perhaps a lousy evening. But, sometimes an extra layover turns into fun… so that’s a possibility.

    For “me” this would be a no brainer in my Bonanza or Baron… heck, could be done in a Skyhawk. And could argue to enjoy the flexibility and capability of one’s plane. (assuming the pilot is capable).

    There is NO severe weather anywhere. Good pilot reports and really pretty good wx at destination. LUK no worse that 2 mi and 12 ovc… almost VFR. Unlikely it will go below mins.

    Now, I would like a bit more info…. especially the freezing level, and more metars and forecasts for the area. However, ice would be easy to avoid, and a descent thru moderate in a deiced plane, into rain is a non issue. All of the ice reports at 150 or higher and only one for moderate.

    If one want to do this trip without getting too wet, they could head straight west northwest, over the ATL area and get on the back side, and come around on the back side. However, I’d recheck the turb reports in the airmet area and see if flight above 8 would work out. Also, would need the metars and TAFs for that route.. but I’d bet it could have almost been done VFR. OR, one could go straight north and come back in on the back side from the north. Personally, I’d go direct.

    Again, I have absolutely NO issue with one cancelling…. THEIR choice. And I’ve cancelled with less… tired, or just didn’t feel like it. But the weather is not the main reason to not fly this trip.

    And, Scott Crossfield’s trip was TOTALLY different, flying into a known area of severe weather.

  13. Ben Sorensen
    Ben Sorensen says:

    In thirty five years of flying, I have never been in trouble for not going. However, several times I have gone and wondered if it was worth it.

    It is better to be on the ground wishing you were in the air, than being in the air wishing you were on the ground.

    • Larryo
      Larryo says:

      Ben,

      I’ve had very few trips that I’ve wondered if it was worth it, but perhaps you have more time than I.

      Also, I could see one getting in trouble if they wouldn’t take trips with weather similar to the above (if they were paid to fly).

  14. Kevin parsons
    Kevin parsons says:

    John
    I took 1 look at the radar before I read the article and knew what the date was before I saw it on one of the charts. That very same day I had a mission to fly from Columbus Oh to Ocala Fla. very tough decision.
    I fly an SR 22 another very capable aircraft. We set out at 8:00 AM from KCMH. A little earlier than at the time the radar depicts. We decided to fly to Columbia SC to eliminate flying through the heaviest of the rain The first wave of hard rain had already passed Cols. we set out with 4000 ft ceilings and light rain. Filed for 7000 and took off. Light to moderate rain until out of Ohio, not much in the way of turbulence,mostly cloudy to SC. Flew the visual and landed for a quick refuel. Took off direct to Ocala and only had to divert a little to the east to avoid some buildups in southern SC. Clear skies in Fla.
    With the absence of red on the radar it wasn’t a very convective day mostly rain and clouds. We made it work that day. You just have to be ready to change your plans at any given time. It doesn’t matter if your on the ground or in the air.

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