Thomas Borchert wrote:

I can see how the basic principles are the same, but I'm guessing my eTrex
wouldn't be happy with the speeds the shuttle is doing.

Many cheaper GPS receiver do indeed have a speed limit. Is it given in the
specs for the eTrex?

There are technology export regulations that limit GPS receivers to
operation below altitudes of 60 kft or below speeds of 1000 knots.
Most consumer models, including the eTrex, are specified to work up to
those limits. However, some units have lower limits - for example,
most Magellan models specify a maximum speed of 951mph.