In late July, I was making plans to do a little oceanfront research, and, as is my habit, I started watching the outlook on The Weather Channel a couple of days ahead of time. From the beginning, it appeared that Maine would beat North Carolina on weather. The morning of the flight, that prediction still held true. The synopsis, fresh from DUAT, said there was a quasi-stationary front south of my Maryland base and that the weather pattern of better conditions north than south would change little. The Weather Channel agreed.
The close-by reporting stations all had 600 feet or so in light rain with the visibility in the 4- to 6-mile range and the surface winds relatively light out of the east. The weather improved markedly to the northeast, according to current reports. The radar reports suggested scattered thunderstorms and showers to the east and to the west of the route, and the maximum tops mentioned were at 25,000 feet. The radar on The Weather Channel supported this. It appeared a nice day for IFR flying.
As I drove to the airport, I thought I had a good mental picture of the weather along the way. The takeoff would be with a relatively low ceiling and restricted visibility in light rain. By the time the airplane reached an area 25 miles north of the airport, the rain should end, and the rest of the flight should be nice.
I never thought about it until later, but a good clue was missed on takeoff. The wind was out of the southwest, and the local weather was a bit better than I had anticipated. Because of this, I should not have been surprised when I started hearing great discussions about deviating around weather ahead, along my route. The warm front, which was supposed to have stayed south for a while, had made a move to the north, and the surface position of the front was actually north of the airport when I took off. The result was building areas of showers and thundershowers across the route. The result was also my working harder than anticipated as I modified the flight path, using the radar and Stormscope, to miss the showers and thundershowers.
This was clearly one of those times when it was incorrect to anticipate an easy flight. What might have been done if the airplane had not been equipped with weather avoidance gear? Some of the first showers that I came upon could be avoided visually, but after that, it would not have been possible. It was morning, and the storms were not strong, but they were strong enough that pilots flying all sizes of airplanes were deviating. There could have been some truly wet and bumpy moments in the middle of one of the thundershowers. It was one of those times when, the weather not being as forecast, the best thing for the pilot of a minimally equipped airplane to do would be to land and get new information.
This weather pattern bugged the forecasters for almost a whole week and, unusual for midsummer, resulted in low IFR conditions for days. Despite predictions to the contrary, it rained on Maine that afternoon, too.
The day after flying to Maine, I returned to Maryland. Where I fly away from home with pages of DUAT information, I usually head for home with some scribbles on a flight log form. The stationary front was still there. Baltimore, close to my home base at Carroll County, Maryland, was forecasting 3,000 scattered to broken with 6 miles visibility, chance of 4 miles visibility in light rain and fog, slight chance of a thunderstorm. It was a 2.5-hour flight, but being suspicious, I was happier leaving Maine with six hours of fuel.
The weather was great for a while, but then I came upon an undercast. The view to the southwest was not too good, either. There was a higher overcast, some dark spots, and the Stormscope started to sparkle in all the wrong directions. I continued checking weather and found that most stations were still reporting low IFR despite forecasts for improvement. The AWOS at home base reported zero-zero, and a call to the unicom verified the accuracy of the report. The only bright spot was Frederick, Maryland, 25 miles southwest of Carroll County. It had 2,500 overcast and 5 miles visibility. Go for it.
I was number three for the approach to Frederick. I could see some weather over there on my radar, and I asked the Baltimore approach controller about this. Baltimore Tracon has the relatively new ASR-9 radar that gives controllers the capability of sorting out levels one through six precipitation, with a digitized presentation on their scopes. In response to my first query, the controller said there was level one (light rain) in the area, north and south of the Frederick Municipal Airport.
The AWOS at Frederick was giving lower and lower visibility as I flew closer. The rain looked harder on my radar, the Stormscope was more active, and the state police helicopter pilot who completed an approach ahead of me said that the weather was much worse than indicated by the AWOS. Then the controller said there was now some level three around Frederick. Having passed Lancaster, Pennsylvania, some minutes earlier, and knowing that Lancaster had both minimums for the ILS approach and a place to have lunch, the prudent decision appeared a retreat. The forecast of a slight chance of a thunderstorm was blossoming into a sure-fire midday event.
Back at Lancaster for gas and lunch, I talked to the FSS and learned that there was a major thunderstorm outbreak in the area. A friend who flew out of Washington National at about that time on an airliner said it was the most turbulent ride she ever had, with the airplane pitching strongly fore and aft and wobbling and passengers throwing up in numbers. I could only wonder if the airline's dispatch system was lulled by the good forecasts.
My wait was relatively short, and the decision to go was based on a telephone conversation with Baltimore Tracon. I got the word that all the bad stuff had moved east. The reward for the wait was a smooth ride home and an approach to minimums — the only above-minimum conditions at the airport for days.
I still look at The Weather Channel days in advance and study the available weather information. This trip, though, was like several others this past summer in that it required a complete change in the mental picture of the weather after takeoff. Accurate forecasting is tough duty when there is a stationary front or a closed low aloft because both are unpredictable. When the forecasts go bad, it becomes the pilot's job to manage any risk that results, and a good way to do this is often to land and start over.
The V speed
I was flying in the west this past summer and relearned an old lesson. The pilot's operating handbook for my 210 says, on takeoff, to use 65 to 70 knots as the rotation speed. This works well most of the time, but when the altimeter reads at or above 6,000 feet for the takeoff and the temperature is high, it is simply not quite enough.
One of the people I visited with this year was Jeff Morrison, proprietor of Morrison's Flying Service in Helena, Montana. The last time I visited with Jeff was 21 years ago, the summer of 1971. We did some real mountain flying together, into some of the back-country strips, and I wrote an article about it. I should have read the article again before going to the hot-and-high country instead of after, but better late than never.
Hopefully, we all know that rotation at any speed other than the ideal speed results in a less efficient operation. This may not matter so much in our big-airport, low-country flying, but it sure does when conditions are hot and high. I realized that using the time-honored 70 knots for liftoff in my airplane was not working well in the conditions encountered, so I crunched the numbers and found 70 far too low, based on good mountain flying practices.
When the chips are down, the procedure is to lift off at 1.2 times the stalling speed for the flaps setting and operating weight. Then accelerate to the best-angle-of-climb speed for the flaps setting, and maintain that until clearing obstacles. (If you are flying below maximum weight and the only numbers you have are for maximum weight, reduce performance speeds by one-half the percentage you are below maximum weight. Ten percent below, reduce speeds by 5 percent, for example.) Based on this, at maximum takeoff weight, 10 degrees of flaps, and average CG location, the rotation speed on my airplane should be 78 knots. That is eight above the maximum shown in the POH. That speed reduces by about 1 knot for each 100 pounds under maximum weight. The best-angle-of-climb speed is 80.
No wonder it was waddling like a duck on some of the higher and hotter takeoffs — I was trying to make it fly too soon.
Traffic
When I was flying over either Nebraska or South Dakota (I can't recall the exact location), without a lot of other traffic around, the controller called and told of another airplane at 11 o'clock, 3 miles, opposite direction. All in my airplane started looking. What's that? A bright streak of smoke? The traffic was an air-show performer, and when he was given as traffic, he let out a shot of smoke. What a neat idea.
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