IFR with a VFR GPS

Gerald Sylvester wrote:

Ron Lee wrote:

"Peter R." wrote:

Ron Lee wrote:

You should note that if you lose lock (too few satellites) then your
display will start flashing (or portions of it). That is not RAIM
which determines if you have a signal error.

Just to clarify, are you saying that a *VFR* GPS's screen flashes
when the
GPS loses the required number of satellites for position calculation and
that error is not a result of built-in RAIM?

Portions do such as position. Take your favorite handheld and look
at various displays. Note that some will flash until you get a solid
GPS lock.


my handheld keeps updating and displaying as though I kept going
straight ahead at the same exact speed and course as when it
lost the lock. So there is NO warning at all.

Gerald

What model is this? I've owned a Garmin 195 and Magellan 500 and both
started flashing if the lost the signal. I had a older non aviation Gps
and as I recall it did not flash when it lost signal. From my
experience and that of other pilots I've talked with all the aviation
GPS tell you when you lost signal. By the way how does your unit update
if you have lost the signal? I can see it freezing and displaying the
same info but how would it update?
John

On Fri, 11 Nov 2005 04:05:09 GMT, John Theune
wrote:

What model is this? I've owned a Garmin 195 and Magellan 500 and both
started flashing if the lost the signal. I had a older non aviation Gps
and as I recall it did not flash when it lost signal. From my
experience and that of other pilots I've talked with all the aviation
GPS tell you when you lost signal. By the way how does your unit update
if you have lost the signal? I can see it freezing and displaying the
same info but how would it update?
John
I have 195. It lets you know when the signal is lost with a message
flashing. I also recall from reading the manual that it interpolates
position, etc. based on speed & heading at time of signal loss for a
short time (x number of seconds?) after loss of signal. If signal loss
is momentary it carries on normally.
I normally use my 195 plugged into aircraft power and with external
antenna. I have noticed that it interferes with the aircraft radio
equipment with static and various buzzes depending on frequency
selected. It does the same to my car radio when I use it there. I do
have some concern that it might interfere with the LOC/GS receiver for
instance, but I haven't seen it affect the accuracy when doing
practice ILS approaches with the unit on.
I have had it go bonkers once when flying very close to VOR Julian
(JLI). It gave the lost signal error message, along with bad position
& direction display, and would not re-aquire until i powered it down
and restarted.