BY DOUG STEWART
Playing the weather game Last month I wrote about my departure from AirVenture 2006 and mentioned the fact that many pilots were rushing to depart between two weather systems. A strong front had swept across OSH from the northwest with a squall line containing some severe thunderstorms that created havoc in its path. A second squall line was following about 80 miles behind the first line, so many pilots were eager to depart between the two lines of weather. I suppose many of those pilots might have been departing to the west, southwest, or south and would soon be far away from the problematic weather. But I was headed eastbound. It wouldn’t take too terribly long until I would catch up to the weather that was leading me on my way back home. What would I do then, and what was my rush to depart Wittman Field? To answer the latter question first, I did have a client scheduled at my home airport for the following day. The client knew that our appointment was dependent upon my ability to get home from OSH, and we both understood the challenges the weather can create for pilots undertaking long crosscountry flights in the summertime, especially when the Great Lakes are involved. My client understood that I endeavor not to fall prey to external pressures when flying and that the appointment might very well get cancelled. If I waited until the second line of weather had passed through and gotten far enough ahead of me to allow a departure, it would delay me too much, meaning that I most likely would not make it home that day. But if I departed between the two systems and played my
cards correctly, there was no reason I couldn’t make it safely home before the day was done. Part of playing my cards correctly was knowing that I had an ace up my sleeve in the form of all the weather information that was available to me in my Garmin 396 portable GPS and XM Weather receiver. It was the proper use of this equipment that would aid me as I caught up to the weather and picked a route around it. In the not too distant past, the best that any of us flying general aviation aircraft had for weather avoidance equipment was “thirdworld radar” (our two eyeballs looking out the windshield) and an ADF to act as a Stone Age stormscope. A handful of folks did have liveweather radar on board, and some of those folks even knew how to use that equipment. That, along with some approach and center controllers who had the knowledge, equipment, and willingness to help, was about the best that we could do in avoiding any serious en-route weather. But those days are history. Now I know that those of us who belong to the Vintage Aircraft Association are steeped in the history of flight. We hearken to a day and age when there was less technology in the world of aviation. We would prefer to hone our stick and rudder skills rather than our buttonology skills. But I must say, if I am going to be taking any kind of a long cross-country flight (read more than 300 miles), whether in my Super Cruiser, or some other vintage aircraft I might be ferrying for a client, or IFR in my Cardinal or my boss’ Navajo, I sure do like to have my XM weather receiver along with me on the flight. So now, as I departed Oshkosh headed toward the serious
In the not too distant past, the best that any of us flying general aviation aircraft had for weather avoidance equpment was “third world radar” (our two eyeballs looking out the windshield) and an ADF to act as a Stone Age stormscope.
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weather that preceded me eastbound, I knew exactly where that weather was. At the touch of a button I could see the NEXRAD radar picture (including a time stamp telling me how old the picture was, which was rarely more than 10 minutes, maximum), I could see graphically which airports were reporting VFR, MVFR, IFR, and LIFR, and if I chose, I could also see a textual METAR as well as any updated TAFs for any selected airport. If there were any storm cells, I could drag the cursor on the screen to the cell and tell instantly the height of the tops, the decibels of rain, and the general direction the cell was moving, as well as where it should be in 15 minutes. Again, at the touch of a button I could read a textual message telling even more about the cell: how wide the cell was; its direction of movement as well as speed; the height of the tops and decibels of precipitation; and the percentage and probability of hail. As AIRMETS, SIGMETS, and convective SIGMETS were issued, I could go to the screen of my receiver and see, graphically, what the limits of those warnings were, without having to try and find the VORs that defined those limits (whose identifiers I knew not) on a chart. I could see the satellite picture as well as echo tops. I could reference winds aloft and request the most effective altitude without climbing or descending only to find out that I had been better off where I had been. I could see reported lightning strikes (more on this in a moment), the synoptic picture (as well as forecast pictures up to four days hence), and more, all at the stroke of a button or two. Having all this weather information available in the cockpit sure makes the airborne decision-making process much easier when adverse weather is involved. It’s obvious that having it is the cat’s meow, but I also have some warnings as well, lest that cat turn into a tiger and bite you real bad. To begin with, we have to always remember that the NEXRAD radar picture is a minimum of five minutes old when it is received in the cockpit. Thus, whereas the information is fantastic in developing a strategic plan for avoiding the serious weather that can ruin our day, it is not to be used as a tactical tool to attempt to penetrate a line of weather. As an example, I used the equipment on my flight out to OSH, to avoid all the bad weather that lay from my home base at the New York-Massachusetts border all the way to just east of Detroit and from Ontario south through the northern half of Pennsylvania. By replanning and amending my route numerous times with ATC, we flew around all the level 4-6 precipitation and the storm cells that went along with it. Although we could see all this weather on the 396, we did not attempt to pick a route through it. Flying around the weather added many miles to my route, but I made it to Wittman Field before the end of the day, without ever coming close to any truly threatening weather. Another caution has to do with the lightning information. When you’re receiving it through datalink services, the only lightning information provided is cloud-to-ground lightning. This lightning occurs in the dissipating stages of a thunderstorm. The cloud-to-cloud and intercloud lightning
that is present in the cumulous (or building) stage of the thunderstorm is not shown on any of the datalink weather receivers. The only place to find this information is on realtime devices, such as the L-3 Avionics Systems Stormscope and the Insight Strikefinder. Also beware that when looking at the graphical depictions of field conditions (VFR/MVFR, etc.) remember that if the icon indicates VFR, it is only saying that the ceiling is at least 3,000 feet and visibilities are at least 5 miles or more. It does not necessarily mean that the skies are CAVU/severe clear. The ceilings might very well be just at 3,000 feet, and you might find yourself unable to descend from your cruise altitude while remaining VFR. No matter what equipment we use to avoid and negotiate the weather we have to keep the words of the “Gambler” in mind. As Kenny sang: “You’ve got to know when to hold ’em, know when to fold ’em, know when to walk away… know when to run.” Regardless of whether we are flying with just two eyeballs out the window or using all the latest and greatest in high-tech weather avoidance equipment, we have to keep in mind the limitations of the equipment. Either type of equipment has the potential to get us into serious trouble. On the other hand, using the equipment properly can help us find . . . blue skies and tailwinds. Doug Stewart is the 2004 National CFI of the Year, a Master CFI, and a DPE. He operates DSFI, Inc. (www.dsflight.com) based at the Columbia County Airport (1B1).
VINTAGE AIRPLANE 33