S Green wrote:

wrote in message ...


Julian Scarfe wrote:


10ish years after overlay GPS approaches were introduced in the US, we

in

the UK still have no GPS approaches. There must be a considerable body

of

evidence collected on accidents, incidents and anomalies over the period
that GPS approaches have been in use. In particular, there may be

evidence

that GPS approaches have improved overall safety in non-precision
approaches.

Any pointers please?

No pointers. Emprically, I'd say they are working great in the US. The

issue

is politics, not safety.


tend to agree. Look who controls the GPS infrastructure. without assurances
that the integrity of the system was not at the whim of the US Department of
Defence, I cannot see the UK authorities being prepared to rely on GPS.
Ultimately this does become a safety issue.

I think it is still politics.


What the US authorities do in their own country and to their own airspace
system is one thing, doing it in someone else's is another.

Do you really think the US would do something that would jeopardize its
own civilian traffic? Also, there are reasons that most aircraft have
multiple navigation systems. Any system can fail and it is only prudent
to have some form of backup. If any country depends only on GPS for
navigation, then the safety issue is theirs.


Matt