Saturday, July 31, 2010

It Was Like Flying Into A Black Hole

Night flight is not everyone’s cup of tea, in fact, some pilots dread it. I can certainly understand why particularly in actual IMC conditions in a single engine plane. But if the conditions are right, good VFR, stars above, maybe a moon, it can be just beautiful. In the distance, airport beacons beam their greeting to the sometimes weary traveler. The twinkle of light from houses, and the stream of headlights appearing as a swarm of bees far below on otherwise unseen roads, all help make up this almost mystical experience. Another thing I miss is the friendly glow of all the cockpit instruments, reassuring at a time of relative isolation. So as long as the machinery keeps on purring, there is nothing particular to worry about. Or is there?

Well, for one, landing at night can be tricky if one doesn’t recognize certain differences from daytime flight. Depth perception is limited and can be misleading to the inexperienced pilot. For example, just before touching down for a landing, during the day one looks straight ahead judging height and distance without much difficulty. At night, with the loss of depth perception, one must use their peripheral vision as a judge of height above the runway. If you try and just stare at what appears to be the runway you may be in for a real bounce. By using peripheral vision as well as straight ahead vision for alignment, judgment of height is much improved. To help the pilot judge the correct approach angle on final, VASI (visual approach slope lights) are a big help. Strategically placed at the end of the runway, they appear red if too low, or white if too high. If one is on the 3 degree slope, the light is a mixture of red and white. In other words, a VFR glideslope. Of course there should be threshold lights, and depending on the size of the field, many others as well. If the field is uncontrolled, frequently one can set the brightness of the lighting system by clicking the unicom frequency appropriately.

I remember one flight into a small airport in southern Vermont, one very dark, moonless night. It was like flying into a black hole. Navigating to the airport was easy using VOR aids. The problem was that there were virtually no surrounding lights other than a couple of red beacons on towers on surrounding hills. Runway lights were minimal, on one side of the runway only. Thank goodness for the VASI. I would have made an ILS approach, except there wasn’t one available. Anyhow, I landed safely, and was glad when I reached the terminal area and could shut down the engines.

So, night owl or not. Make sure your eyes are night adapted, keep lighting low in the cockpit and enjoy the darkness.

Monday, July 19, 2010

It pains me to read of another crash

It pains me to read about another plane crash, with all occupants dead, and no explanation other than “pilot error”. The pilot, older, with many years in the cockpit, should have been able to avoid the crash. From what I gather, the landing was balked because the plane was too fast and possibly high for the 4000 foot runway. You just can’t force some planes down on the tarmac if they aren’t ready. The result if you try, is to bounce, possibly porpoise, even hit the prop, as happened here. And, oh no, just read of another landing accident in a similar plane with similar terrible results, several days later.

As I smoke my philosophical pipe, feet propped up, and reflect on things, I wonder why things happen as they do. Have we become complacent to the point of relying on things
rather than knowledge, inherent to what we are doing. Is basic aeronautical science too abstract for the average pilot these days? Are flight instructors too casual in their teachings? Do they put their students through the rugged paces needed to deal with those
unplanned events that can lead to serious trouble? I mean really, a pilot should be able to handle a balked landing with the adroit application of power, and then proceed to land the plane once stabilized, again at the proper speed and attitude. That, as compared to trying to force or slam the plane down on the runway, when it still has enough energy or speed to fly.

Now, in all fairness, some planes are more difficult to land than others. One of the newer fixed gear, speed demons can be difficult to land from what I read. I am of course thinking about the Cirrus. The recommended approach speed is 78kn (1.3 Vso*). That is considerably faster than a Cessna 172RG, a somewhat comparable plane. Slower, but still a notch above many. I used to fly one, and enjoyed it. Vso of the RG was 50kn, and 1.3Vso was then 65kn. Considerably slower than the high performing Cirrus. I am wondering if the pilots that are having problems landing that bird are just not ready. Maybe, and this is only my opinion, they should have more hours flying the lower performers, as the C172’s until they have more flying experience. Then transition to the next higher category. Much as what I did, moving into the light twin category from singles.

On a technical note. One must remember that the kinetic energy of a moving object is proportional to the square of velocity. Therefore, landing at Vso in a Cirrus has 1.44 the energy to dissipate as compared to the Cessna 172 also at Vso. In a crash then, or in an emergency braking situation, there is almost 50% more energy to deal with at the higher speed. That can be a problem.

So, in summary. Getting there fast is nice, but really not all that important in the scheme of things. Rather, just lean back and enjoy the process, no matter how long it takes. When you reflect on your flying experiences, years later, you will remember the process, not how long it took.

*Vso- Stall speed in the landing configuration