All was not lost, after some informed decisions with altitudes we made the trip in 3:36 despite the headwinds. Why? Because the Central Valley of California is a meteorological cesspool. I make no commentary on the CV otherwise but with towering mountains in nearly every direction air tends to get trapped and there isn't much wind, usually. This was the case on Monday afternoon and I was able to take advantage of the stagnant low level air in the CV to get to my destination faster.
My usual wisdom for the RV-8 is that higher is better, even if that means dealing with a strong headwind. The air is thinner and for the same fuel burn the plane will go faster. This flight was an exception.
The first part of the flight I had to get over the LA airspace and that forces you to either follow preplanned routes through their airspace or go over at 10,000 feet or higher. I opted to go higher which gave me a headwind of around 30 knots. After I crossed the Tehachapi Mountains I was able to descent into the CV where the headwind turned into a tailwind at times.
The amazing thing is that there was a Cessna 210 that flying the same direction as me. The normally aspirated C-210 has about the same cruise speed as my RV-8 but this driver decided not to descend into the CV and I left him in the dust. Below is an annotated plan and profile view of the flight:
Also noteworthy in the first part of this flight I traversed an area with mountain wave. There are plenty of other places that cover what wave is but for this conversation I'll just say that downwind of a mountain, mountain range or ridge, above the level of the ridge, sometimes you find areas of air that are rising(lift) and falling(sink). These areas are situated in bands perpendicular to the wind direction(parallel to the producing ridge). Think of the air "bouncing" as is goes down wind. So in this case I encountered mountain wave created by the Tehachapi Mountains. The autopilot(or manual pilot) response to this is usually to hold altitude. Holding altitude in this situation results in speeding up in lift and slowing down in sink. If you are trying to go from point A to B through a wave area this might be the worst possible strategy. You go slow in the falling air spending the most time trying to out climb the sink and then you dive quickly through the rising are. In this case I was seeing variations of 60 knots true airspeed. Another approach to get your power plane through a wave area faster is to intelligently allow altitude to vary rather than trying to maintain altitude. The glider pilots might call this "porpoising", flying the "McCready Speed" or maintaining the Speed to fly. Generally, the idea for a glider is to spend more time in rising air and as little as possible in stagnant or falling air. For a given set of conditions there is an ideal speed to fly a glider, generally fast in sink and slow in lift but you can get very technical and figure out exactly what the optimal speed is. You don't need to take it to that extreme but if you allow the plane to rise when you encounter an area of lift and then descend in the sink you will end up with a higher overall speed through the wave area. Depending upon your desired direction of travel relative to wind you may be able to alter your course left or right a few miles and pick lots of extra airspeed.
Beware though, I didn't mention that under the crest of each wave, at about the altitude of the producing ridge you will find truly horrendous, potentially life threatening, potentially airplane breaking, very much so "spouse will never fly with you again" turbulence called the rotor. Also, even if you're above the the rotor you may not be able to out climb the sink, sometimes the air will sink at 5000 feet per minute! You've been warned!
All of this high level flow was a precursor to a winter storm coming and I forgot to mention that we "had" to make our way back the next morning... So here is what the prog chart looked like in the morning:
That cold front passed Norcal overnight and it along with the low pressure system was also kicking up some serious winds in Redding: gusting to 39 knots when we took off at 7AM. The outside air temp at 6500 feet was a balmy 17 F(-8 C). You'll notice that the cold front is located right at the southern end of the cesspool, I mean Central Valley. Cold fronts are masses of cold air moving in the direction of those blue pointy things. Cold fronts travel along the ground because cold air descends so it consequently lifts the warmer air ahead of it. Meanwhile at temps below 20 F(-7) my RV-8 becomes uncomfortably cold. Keep those things in mind.
Here is the wind situation at 12000:
So going home I can pick up a huge tailwind if I can just get up to 12000 and stay a little west of the direct route but it might be really cold up there... What to do?
Well, firstly always have an out. The central valley had good weather because the cold front passage cleared the cesspool out. The weather at the actual cold front, as expected was bad, ice, low clouds, rain. Once we got to the area of the cold front we were forced to either bag it or climb over. The unknowns here are how high, how cold and for how long?
Flight service tells us that all the stations from the front south are reporting overcast skies so that means that if we can't go on instruments to descend into our destination then we must turn around and land in the CV. We(pilot and plane) are instrument rated so we go for it, climb over the cold front and find out that it is clear above 10000 and even better, just as advertised in the meteo books, the cold front lifted the warm air ahead of it, so after freezing my tokus off at 6500 in 17 F(-8C) I'm up at 11500 in 39 F(4C) basking in the warm sunshine. This is exactly the opposite of a usual temp profile during a climb: all things being equal every 1000 feet climbed should reduce the temperature by roughly 3 degrees but cheerfully there are exceptions and this was one of them.
We(PAX, Pilot and Plane) shot the instrument approach back in to home base and we(wife and I) made it to work by 11 AM.
Not a bad 22 hr trip.
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