I fly out of KALM in Alamogordo, NM, alt.4200, DA usually 6000 and UP. We have
a lot of whirlwinds, dust devils we call 'em. These things can extend 1000 ft.
or more into the atmosphere and pack a nasty surprise for the unaware or
unsuspecting pilot. They are like mini-tornados with a top of 200 ft. or more
in diameter. That is the "visible" top that can be seen from the airborne dirt,
the affected area is much larger. I remember reading that the wind velocity can
be 100 mph or more at the top.
I can remember as a kid running into these things to get to the "eye", and
yes there is an "eye", but it is small and hard to keep up with on foot. Of
course, the "devils" are smaller and slower on the ground than they are at
flight level.
While these things can be unsettling at altitude, they can be disastrous
during the takeoff or landing. If there is no available loose dirt, these
things can be damn near invisible with the only clue being the movement of
ground cover. Imagine a sudden 360 degree circular crosswind of about 25 mph or
more gathering you up as you get light. That's what I think Mike experienced.
If you're flying in the west these babies are an occupational hazard. AOPA
website probably has some info on this but the best advice is "see and avoid".
Ken
