It is still absolutely amazing to me that I can wake up in Houston at 0600, walk the dog, have a little breakfast, then pull the airplane out of the hangar and launch at 0700 for California. Eight hours and two very leisurely fuel stops later, I?m sitting in our cabin in the mountains, the heat and humidity of the Gulf Coast a distant memory. All this in an airplane I built in my garage, arriving with the contents of my pockets intact ? including my pocket knife! What do you suppose an American pioneer of 150 years ago would think of such magic? For them, leaving St. Louis for the west was the beginning of a life-threatening ordeal that would last at least several months if they were to reach the far west at all. Yup?.magic is about the only word I can think of!
But the real magic of this trip was cruising along in mostly calm and still air for a change ? little turbulence, winds less than ten knots at al the altitudes I was flying, alternating between head and tail ? with a lucky tip towards the tail! Today was a dawn departure, the sun peaking over the trees as I lifted off, to avoid the heat of the day over the desert. The usual fuel stops are Pecos and Casa Grande (although the Valkyrie can do it as a two-hop, it is frequently cheaper to stop short for a good gas price), but a plethora of odd NOTAMS about the Pecos runways, and fifty-cent a gallon cheaper gas at Andrews (E11) made it worthwhile to alter the course a bit. IFR conditions (low visibilities) predominated across Texas east of the Hill Country, but it was clear in Houston when I left home, and I cruised over the foggy coastal plains seeing plenty of breaks down below. Most of the stations reporting IFR were at airports in the river bottoms ? it really was a nice day to fly!
The only problem I have with a day like this is the fact that it is still summer in the Southwest, which means it is still HOT. This, in turn, means that density altitudes are pretty high. I was cruising at 10,500 today to catch the minimal winds, and the DA was close to 13,000?. Why is this a problem? Well, the engine loses horsepower with increases in density altitude. It is pretty common knowledge that we will get the best performance out of our non-turbocharged airplane at about 8,000?. On a standard day this is where the engine will put out about 75% power at full throttle. Lycoming tells us that this is what we should consider ?Max Continuous? cruise power. Of course, from a drag standpoint, higher is better ? but as drag drops off, so does engine horsepower. Since we can get more than 75% below 8,000?, we see an increase in TAS up to that point, and above that, we start to lose speed ? airspeed that is.
So why do we like to cruise higher (I prefer about 12,000?)? Because we can gain back a lot of ground speed if the winds are with us, and the higher we go, the less fuel we burn (A consequence of putting out less horsepower). The best days are when we can get up high to save fuel and catch a tailwind to keep the speed up. Headwinds keep us down low of course, but boy, just watch the mpg climb when you are eastbound in the winter and cruising high!
So a summertime flight like this brings on the doldrums?.instead of the nice 170 knots I usually get, I was down around 163 most of the time. It was an odd day in that the lower winds were up high ? but the DA?s were also high, so that there was little way to win. Higher was smoother and cooler ? and that won out. The moonscapes of western Arizona and Southeast California are at least fascinating to watch as the time goes by, and San Gorgonio ? the northern guardian of Banning Pass, and my marker for Big Bear ? swam out of the haze at a range of 110 miles ? not bad, considering what I put up with on a daily basis! My attitude always improves with altitude, especially when that altitude is the height of a mountain lake with pines all around.
Magic transportation machines, these RV?s?.
Paul
But the real magic of this trip was cruising along in mostly calm and still air for a change ? little turbulence, winds less than ten knots at al the altitudes I was flying, alternating between head and tail ? with a lucky tip towards the tail! Today was a dawn departure, the sun peaking over the trees as I lifted off, to avoid the heat of the day over the desert. The usual fuel stops are Pecos and Casa Grande (although the Valkyrie can do it as a two-hop, it is frequently cheaper to stop short for a good gas price), but a plethora of odd NOTAMS about the Pecos runways, and fifty-cent a gallon cheaper gas at Andrews (E11) made it worthwhile to alter the course a bit. IFR conditions (low visibilities) predominated across Texas east of the Hill Country, but it was clear in Houston when I left home, and I cruised over the foggy coastal plains seeing plenty of breaks down below. Most of the stations reporting IFR were at airports in the river bottoms ? it really was a nice day to fly!
The only problem I have with a day like this is the fact that it is still summer in the Southwest, which means it is still HOT. This, in turn, means that density altitudes are pretty high. I was cruising at 10,500 today to catch the minimal winds, and the DA was close to 13,000?. Why is this a problem? Well, the engine loses horsepower with increases in density altitude. It is pretty common knowledge that we will get the best performance out of our non-turbocharged airplane at about 8,000?. On a standard day this is where the engine will put out about 75% power at full throttle. Lycoming tells us that this is what we should consider ?Max Continuous? cruise power. Of course, from a drag standpoint, higher is better ? but as drag drops off, so does engine horsepower. Since we can get more than 75% below 8,000?, we see an increase in TAS up to that point, and above that, we start to lose speed ? airspeed that is.
So why do we like to cruise higher (I prefer about 12,000?)? Because we can gain back a lot of ground speed if the winds are with us, and the higher we go, the less fuel we burn (A consequence of putting out less horsepower). The best days are when we can get up high to save fuel and catch a tailwind to keep the speed up. Headwinds keep us down low of course, but boy, just watch the mpg climb when you are eastbound in the winter and cruising high!
So a summertime flight like this brings on the doldrums?.instead of the nice 170 knots I usually get, I was down around 163 most of the time. It was an odd day in that the lower winds were up high ? but the DA?s were also high, so that there was little way to win. Higher was smoother and cooler ? and that won out. The moonscapes of western Arizona and Southeast California are at least fascinating to watch as the time goes by, and San Gorgonio ? the northern guardian of Banning Pass, and my marker for Big Bear ? swam out of the haze at a range of 110 miles ? not bad, considering what I put up with on a daily basis! My attitude always improves with altitude, especially when that altitude is the height of a mountain lake with pines all around.
Magic transportation machines, these RV?s?.
Paul
