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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.
My student and I had a huge
night in company with some USAF IP's out of Williams AFB, similarly diverted by
weather to Biggs. 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, 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 the could clear us to a higher altitude, they
were desole, simply desole.
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.
Anyway, 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
blunder 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 (short) time, the thrust 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, judgment is called into
doubt.
Or, 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, etc into the rotor section
itself, causing untold damage to the thing that makes airspeed: 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.
Either
way.
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. And then... 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.
Baggage.
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