The hurricane hitch should be able to withstand winds of 150 knots, given
rope of adequate strength. This is the only knot that should be used for
tieing down aircraft, yet my personal observation is that fewer than one
pilot in 50 knows how to tie it. The knot is described in E.F. Potts' book
on bush piloting.

Chains are worse than inadequate as tiedowns. They cannot be attached
without some slack remaining, and sudden stretching of the chain will cause
it break when it snaps taught. Loose and broken chains are also dangerous in
and of themselves. A rope can be made tight, so that all stretching is
continous and there is no sudden stop.

Aircraft owners should carry their own lines and ensure that they are in
good condition. They should also make sure that their tiedown rings are in
good condition and, if strong winds are expected, should consider
reinforcing the tiedown by giving the line a couple turns around the strut
as well as running it through the tiedown ring.

Even tieing an airplane down is not a guarantee against damage. Winds may
still generate enough lift that the airplane could be damaged anyway. There
is one picture of a severely damaged Bonanza that pulled the concrete
tiedown blocks completely out of the ramp, collapsing the nose, wrinkling
the wings, and probably damaging the wing spars in the process! Tied down
airplanes can still be damaged by flying debris (such as improperly tied
down airplanes) as well as by severe hail and other things caused by the
weather.

Cessna recommends tieing aircraft down at both nose and tail, though this is
rarely done and few tiedowns have provision for doing this. A gust striking
an airplane that is tied only at the tail and wings can still send the tail
slamming down hard on the concrete, breaking it off. Gusty winds can make
the airplane bounce on its nose gear, too, possibly damaging the nose gear,
firewall, engine mount, propeller and engine. The airplane can also be set
on its tail by heavy snow or ice.