Backup gyros - which do you trust?

Big John writes:

Sidney. All of the above G The approach plate gave the time to
field in minutes and seconds listing several speeds to accommodate
all the aircraft in inventory. Normally max time would only be 3-4
minutes and normally just 1-2 minutes after crossing cone of
silence. You rarely landed straight in and many of the headings to
field were not lined up with a runway. After sighting the field you
would circle and land on the active runway. If you were in radio
contact with the field/tower you could get surface wind and compute
a ground speed from cone of silence to field, other wise you made a
WAG from forecast and what you encountered en route.

This does not sound a lot different from a typical NDB approach today,
when the NDB is off the field.


All the best,


David

--
David Megginson, , http://www.megginson.com/