By lex, on October 10th, 2003
It does rain in Southern California…
Rainy commute to the air station this morning. Kind of a tentative rain, like maybe it wasn’t sure this was entirely appropriate. Reduces the fun factor of motorcycle commutes by, oh twelve thousand percent. A bummer, but I made it there, and made it back, so all’s well, etc…
On a dry road, a bike can stop in about half the distance of a car, especially when it has ABS, like my bike does. The stopping force of the dual caliper brakes on two wheels when applied to the drastically reduced weight (as opposed to the standard car, with the usual appointments), sets up a very favorable ratio for dissipating kinetic energy. The reverse principle for thrust (torque) to weight makes it fun to hit the go switch, too.
All these advantages are exploded utterly when the pavement gets slick. Especially the ungrateful SoCal tarmac, so unused to the watery affections of the sky. Exhaust oils and rubber deposits make the streets treacherous, all the more so since they are so infrequently washed away. It was only mist at first to LaJolla, then the fine, soft rain came down, . Not enough to make me push my high school senior son out of the car we ostensibly share, but enough to make me wish it wasn’t so. Still, you must deal with the sea as it is, and not as you wish that it might be. Keeps you on your toes.
Once when I was a young Lieutenant Junior Grade, and an instructor pilot, I was forced to divert into Biggs Army Air Field by an impenetrable line of thunderstorms athwart my path. The jet I was flying at the time was incapable of overflying the tops (40,000 feet) without snuffing one or two of the motors, and without weather radar, there was not the remotest chance of rooting a way through. Plus it was getting dark. Talk to any aviator and mention darkness, terrain and thunderstorms and you can pretty much watch his hair turn grey in front of you. You don’t go there, not twice anyway, not by choice.
Having landed successfully completed our divert to Biggs, my student and I had a huge night in company with some USAF IP’s out of Williams AFB, similarly impacted by the weather. We had our side to keep up, the reputation of the service, etc. The next day we were off, on the way to Mississippi. In the nature of things, flying west to east, you’ll see the weather you avoided last night the next morning. Our judgment clouded a bit perhaps by the aftermath of the previous evening, combined with a chain of command generated pressure to get that $)(@#*( jet home so someone else could use it, we pressed on, hoping for the best. As we approached the weather front, it became clear that we weren’t going to get over the top at our altitude. The air route traffic control center was sympathetic, but there was no way they could clear us to a higher altitude, they were desolé, simply desolé.
Fair enough, we said. Any chance we could hold in our current location, potentially shuttling up to the next higher route structure? “Stand by,” we were told. Now, talk to a Sailor in the passageway and ask him to “stand by,” and he’ll do just that. Doesn’t cost him nuthin’. But for aviators engaged in actual aviation, the words “stand by” really mean, keep going, at a rate of a mile every 10 seconds, right where you don’t want to be going.
By the time our clearance for a circling climb had come, we had entered the clouds. No use now to throw whatever excess lift and thrust we had in a circling maneuver, best just to stumble on and hope for the best. Which came in the form of a gradual reduction of thrust as the ice started to accumulate on the inlets and guide vanes.
Now we were in a pickle: Let the ice continue to accumulate, and eventually you’ll lose your ability to gain altitude. In (a very short) time, the thrust/drag curve turns negative, and you’ll start to settle, losing altitude and falling right into the seventh circle of hell that constitutes the heart of a massive, mature thunderstorm. Ice, hail, turbulence like you’ve only read about in books. People have ejected, pointed questions are asked at long tables where everyone but you gets an ashtray – your judgment is called into doubt.
The alternative was to individually reduce power on each engine, subsequently slamming the throttle forward. This serves to break the ice free. Once liberated from the intake and inlet guide vanes, it goes where it must, straight into your fan blades, slender reeds of aluminum spinning at, oh, 33,000 RPM. They’re cold, and the ice is hard, so there’s a chance that a bit of blade might break off, falling into the next fan section, where it might knock three or four pieces of that disk, and so on into the rotor section itself, causing untold damage to the thing that makes airspeed with unfortunate results: compressor stalls, loss of thrust, etc. This makes the problem come back ’round again full circle to the whole “can’t maintain altitude” issue. Which sucks.
I preferred to be an active participant in my fate, so I merrily slammed away at the throttles, watching with growing alarm as my rate of climb indicator moved gradually from a positive figure (getting above the madness) to a figure more closely approaching zero. Next would come a rate of descent, regardless of how carefully I managed my angle of attack (very carefully indeed!). As the pointer reached level, I tightened my harness restraints, thinking “This is going to be interesting.” And then suddenly… we broke free! Out of the clouds. The engines almost immediately gained efficiency and we were able to continue a climb to an altitude well above the rest of the dissipating storm.
And I learned about flying from that. As my student had, hopefully. Who hadn’t said a word in the last ten minutes.