The 'preferred' option is to have a loc frequency automatically force the
NAV/GPS switch to go to nav mode.


Almost all wiring suggestions imply that as the deafult mode.

So you barrel along with your gps upto the IAF cros tracking your favourite
VOR then swap frequencies
on nav1 and bingo your automatically lined for a loc intercept.

Personally I find it it irrating and also if P2 happens to tune the ILS/DME
for cross references
purposes and the A/P is on then you can do a beautiful intercept of the ILS
for an airfield you just
happen to be passing!!


Peter


"Stan Gosnell" wrote in message
...
(Ben Jackson) wrote in
news:PeIab.524381$uu5.87404@sccrnsc04:

What ACUs will allow you to select GPS display when a LOC
frequency is tuned in on the NAV? I know UPSAT's won't
actually select the GPS until you tune a normal VOR on the
associated NAV.


With the installations we have, the HSI has no idea what's
selected, or what frequency. There's a push/push button, which
cycles between VOR & GPS, and the HSI just gets voltage from
whichever is selected. There is no logic at all to prevent
using either one. The nav radios and the GPS are completely
independent, and have no relation to each other in any way.

--
Regards,

Stan