> Here's a tip to easily calculate the reciprocal bearing for a
> beam headings. Mentally adding or subtracting 180 can be
> difficult under adverse conditions.
> If the bearing is less than 180 degrees, add 200 then subtract
> 20. Easy math.
> Conversely, if the bearing is greater than 180 degrees, subtract
> 200 and add 20.
> Another tidbit, if you deal with bearings divisible by ten, the
> sum of the "tens" plus the "hundreds" will be the same as the sum
> for the reciprocal. Example, for 50 degrees (or 050, if your a
> purest), the reciprocal is 230 degrees. 0 + 5 = 5 and 2 + 3 = 5.
> It makes a good check of your math.
> I learned these from my flying days when sometimes just keeping
> the wings level commanded lots of metal resoures.
> Chuck, KE4OAR
This reminds me when I was backpacking at Big Bend NP in the Chisos
One sign right at the trailhead said there were bears in the park. The
recommended procedure if you encounter one and it gives no indication of
moving on, is to drop your pack and curl up behind it and play dead.
About 50 yards farther down the train another sign said there were mountain
lion in the park. The recommended procedure if you encounter one and it
gives no indication of moving on, is to throw rocks, make noise, jump up and
down and generally try to scare it off.
About a mile up the trail, I could not remember which to do in case of
encountering one or the other and I was absolutely sure I wouldn't remember
in the heat of the situation.
Another case is the old saying about coral snakes: Red & Black, friend of
Jack; Red & Yellow, kill a fellow." Like I'm going to remember that if I
encounter a coral snake (R&Y) or Mexican milk snake (R&B).
No offense, Chuck, but I think I will stay with my addition/subtraction by