Navigation flight planning during training

On Mar 13, 8:40 pm, "Andrew Sarangan" wrote:
Thanks for pointing out diversion. But I would consider that to be an
argument against doing extensive paper calculations. Diversion is not
done with an E6B, plotter and a flight log. It is done by taking a wag
at the course and distance, making a reasonable assumption about wind
and variation and coming up with rough heading and time.

First off, it depends on the diversion. Not every diversion is
complete in a matter of minutes, although that is the only kind that
gets tested on the checkride. In the real world of flying VFR XC, you
may well find yourself diverting to an airport 100+ miles away. Maybe
it's to go around weather you didn't expect, maybe it's because
headwinds are greater than anticipated and suitable airports are not
so close together as one might like, maybe it's because a TFR popped
up. In those cases, you should do at least a little calculating.

But even a short range diversion is done by approximating the steps
that are fully computed in paper flight planning. Now the problem is
that most people have a difficult time approximating something they
never really learned to do exactly. See Roy's response on this - and
I've had the same experience he has. People get out of the habit of
doing the full procedure, and then when they need to do an
abbreviated, approximate procedure they can't do that either. The
ability to take a wag at the course and distance quickly and
accurately really only comes from having computed it multiple times
and observed patterns.

If it were up to me, we would go back to the 30 minute XC plan. That
would force the student to keep drilling for speed, and through sheer
repetition he would start gettting a feel for what the results ought
to be.

So the original question
still remains. Why not do all ground planning by computer, and if
anything unusual happens during flight, fly it like a diversion?

Because if you can't do the steps on paper, on the ground, what makes
you think you can do them even approximately in flight?

It is important to
understand why we teach certain things. Most aeronautical information
is simply passed down from one CFI to the next, and many things are
done by habit instead of reason.

I agree. And there are things that I think could be safely dropped
from the paper planning process. Compass deviation? Trying to
correct out those sub-5-degree errors by looking at a whiskey compass
bouncing around in the turbulence? Get real. It may have made sense
in the days of dead reckoning hundreds of miles at a time, but those
days are gone. These days, we dead reckon at most 50 miles.

And the moronic triple-interpolation for takeoff and landing distance
in those Cessna books? Waste of time. Round up the temperature and
altitude, round down the pressure, and call it good. Gives you a
little cushion (little enough, the way most rentals are maintained).

But the fundamentals - choosing checkpoints, correcting heading for
wind and magnetic variation, estimating climb fuel and cruise fuel -
you have to know these things.

I have yet to see a convincing
argument for the pen & paper method, except for claims that it is
'basic information all pilots should know'.

Well, it is. Because without it, the approximate methods used in a
diversion will be meaningless (since the student won't understand what
he is approximating) and thus quickly forgotten. Not that I'm sure
this isn't happening already.

Michael