Need a 2nd nav with GNS 430?

wondering if a 2nd nav is really a necessity with a GNS 430 in the panel.

Don't put all your eggs in one box.

1: the display fails, you're toast. HYBT
2: RAIM error in IMC is also inconvenient. BTDT
3: if you can't update the database (such as you're in the middle of a
trip during the window) you can't do IMC anymore. BTDT - at Sun'n'Fun,
no less.
4: you're in some bumpy clouds, reach over to switch off the strobes or
switch on the pitot heat or something, and a bump causes you to hit the
master. Oops - flip it back on. VORs come right back. NAV comes right
back. ADF comes right back. DME comes right back. GPS begins to
acquire satellites, do its self test, and waits for you to push the
lawyer button before continuing. Meanwhile, you're doing 150 knots in
the soup and just got an amended clearance. BTDT
5: New clearances are often easier to dial into a VOR to start with, so
while you push the GPS buttons you're at least flying the clearance. BTDT
6: If you have an electrical failure in IMC, you may need to decide
what units to leave on the battery and what units to shut off. I don't
know the 430's current draw; you may be better off with just a single
VOR in some cases (though I wouldn't be surprised if the old VOR
receivers draw more than the new GPSs). BTDT, though without the 430.

That's just a start.

Jose
(r.a.h retained, though I don't follow that group)
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

Jose wrote:

3: if you can't update the database (such as you're in the middle of
a
trip during the window) you can't do IMC anymore. BTDT - at
Sun'n'Fun,
no less.

Is this a specific limitation spelled out in Garmin's POH supplement?
Not that I have done this due to burning my own cards and maintaining a
current subscription, but I was under the impression that one could
even fly an approach with an expired database, as long as a) the GPS
supplement doesn't restrict this and b) the pilot verifies the GPS
approach with a published approach plate.

If you burn your own database cards, you will note that the database
update for the Garmin GNS430/530 is normally released (at least here in
the US) ten days or so before becoming current. I suppose it is not
unrealistic to be away from home longer than ten days, but that does
provide some amount of time to plan for the expiration.

BTW, you raise some excellent points about the GPS being a single point
of failure. I also have also experienced three different GPS problems
during three different flights that rendered the unit inoperative for
five minutes or so per event. One was my fault, as I opened a bottle
of water at altitude that sprayed all over the GPS, thanks to the
pressure difference. The MSG button temporarily shorted out and I
could not see any page except the message page.

The other two problems were GPS software related. Of these two, the
notable one occurred when the database card I had in the unit became
*current* during my flight (at the crack of 00:00z of the new day - I
had placed the card in a day early for the flight). This was a
Bendix-King KLN-94 GPS and at the crack of 00z, a message appeared
stating that the unit needed to be rebooted due to the database
becoming current. Ridiculous of the unit to do this, but it caught me
with my pants down as the unit could not acquire satellites right away
upon rebooting. IMC at night and I did not have the VORs set as
backup. I scrambled to set up my VORs and only managed to drift off
course by a mile or two before getting back on course. That was a good
lesson.

--
Peter

3: if you can't update the database (such as you're in the middle of
a trip during the window) you can't do IMC anymore. BTDT - at
Sun'n'Fun, no less.


Is this a specific limitation spelled out in Garmin's POH supplement?
Not that I have done this due to burning my own cards and maintaining a
current subscription, but I was under the impression that one could
even fly an approach with an expired database, as long as a) the GPS
supplement doesn't restrict this and b) the pilot verifies the GPS
approach with a published approach plate.

I don't know if it's spelled out in the POH supplement, and it's not
handy right now. If you do the approach and land uneventfully, you will
probably not have a problem. If you do the approach and have an
incident which brings you to the FAA's attention, you could probably
count on a "careless or reckless" charge. If there was a significant
change to the approach, it might be difficult (depending on the change)
to fly the mod by hand, since it's not in the box.

Yes, they give you ten days. In my case, the new database was burned to
a spare card before my flight, but I didn't have the spare card and
didn't know until the flight that the database was about to expire. At
Sun'n'Fun, I went to the Jepp booth to update my card, and there were
"no more updates available", meaning that my quota of burns had already
been burned (we have three aircraft and three subs). So, Jeppesen would
not update my card, and it took a bit of "discussion" and several long
distance phone calls before I could convince them to add one to my quota
and let me burn the update.

I consider this to be a safety-of-flight issue, and I wonder how Jepp
would come out after an accident.... no, actually I do know how they
would come out. "After all, I didn't have to make the flight in the
first place."

Jose
r.a.homebuilt retained, though I don't follow that group
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

Jose wrote:

don't know if it's spelled out in the POH supplement, and it's not
handy right now.
snip

I started to research this and the quickest place to find some info
about this was AOPA's GPS Safety Advisor. Sure the information is in
the AIM and I will get right back to it, but this was a faster link for
me:

http://www.aopa.org/asf/publications/sa01.pdf

Pertinant Quote:

"For en route flying, it's legal - but not wise -
to use an expired database, as long as the pilot has
available current information, such as current low
altitude en route charts, to manually check and
correct any data that's changed."

I will look later for more details about approaches.

--
Peter

I have three 430/530 installations, two in the MU-2 and one in the Helio.
None of the Flight Manual Supplements require a current database for
approaches.

Mike
MU-2

"Peter R." wrote in message
oups.com...
Jose wrote:

3: if you can't update the database (such as you're in the middle of
a
trip during the window) you can't do IMC anymore. BTDT - at
Sun'n'Fun,
no less.

Is this a specific limitation spelled out in Garmin's POH supplement?
Not that I have done this due to burning my own cards and maintaining a
current subscription, but I was under the impression that one could
even fly an approach with an expired database, as long as a) the GPS
supplement doesn't restrict this and b) the pilot verifies the GPS
approach with a published approach plate.

If you burn your own database cards, you will note that the database
update for the Garmin GNS430/530 is normally released (at least here in
the US) ten days or so before becoming current. I suppose it is not
unrealistic to be away from home longer than ten days, but that does
provide some amount of time to plan for the expiration.

BTW, you raise some excellent points about the GPS being a single point
of failure. I also have also experienced three different GPS problems
during three different flights that rendered the unit inoperative for
five minutes or so per event. One was my fault, as I opened a bottle
of water at altitude that sprayed all over the GPS, thanks to the
pressure difference. The MSG button temporarily shorted out and I
could not see any page except the message page.

The other two problems were GPS software related. Of these two, the
notable one occurred when the database card I had in the unit became
*current* during my flight (at the crack of 00:00z of the new day - I
had placed the card in a day early for the flight). This was a
Bendix-King KLN-94 GPS and at the crack of 00z, a message appeared
stating that the unit needed to be rebooted due to the database
becoming current. Ridiculous of the unit to do this, but it caught me
with my pants down as the unit could not acquire satellites right away
upon rebooting. IMC at night and I did not have the VORs set as
backup. I scrambled to set up my VORs and only managed to drift off
course by a mile or two before getting back on course. That was a good
lesson.

--
Peter

On Thu, 05 May 2005 00:22:53 GMT, "Mike Rapoport"
wrote:

I have three 430/530 installations, two in the MU-2 and one in the Helio.
None of the Flight Manual Supplements require a current database for
approaches.


Does the language in the GNS530 pilots guide, page 4:

"The database confirmation page appears next and shows the current
database information on the NavData card (with the valid operating
dates, cycle number and database type included). The database is
updated every 28 days and must be current for approved instrument
approach operations."

not create a requirement that the database be current to use the unit
for GPS or overlay approaches?

No, it is the flight manual supplement that is controlling. There may be
different supplements out there with different requirments too.

Mike
MU-2


"Peter Clark" wrote in message
...
On Thu, 05 May 2005 00:22:53 GMT, "Mike Rapoport"
wrote:

I have three 430/530 installations, two in the MU-2 and one in the Helio.
None of the Flight Manual Supplements require a current database for
approaches.


Does the language in the GNS530 pilots guide, page 4:

"The database confirmation page appears next and shows the current
database information on the NavData card (with the valid operating
dates, cycle number and database type included). The database is
updated every 28 days and must be current for approved instrument
approach operations."

not create a requirement that the database be current to use the unit
for GPS or overlay approaches?

Jose wrote:

3: if you can't update the database (such as you're in the middle of a
trip during the window) you can't do IMC anymore. BTDT - at Sun'n'Fun,
no less.

Chalk another one up for the 480...you can load two cycles up and it
auto switches.

4: you're in some bumpy clouds, reach over to switch off the strobes or
switch on the pitot heat or something, and a bump causes you to hit the
master. Oops - flip it back on. VORs come right back. NAV comes right
back. ADF comes right back. DME comes right back. GPS begins to
acquire satellites, do its self test, and waits for you to push the
lawyer button before continuing. Meanwhile, you're doing 150 knots in
the soup and just got an amended clearance. BTDT

Does not the 430 NAV section come up immeciately?


6: If you have an electrical failure in IMC, you may need to decide
what units to leave on the battery and what units to shut off. I don't
know the 430's current draw; you may be better off with just a single
VOR in some cases (though I wouldn't be surprised if the old VOR
receivers draw more than the new GPSs). BTDT, though without the 430.

Depends on what your other radio is. If it's comething modern like
an SL30, you're probably OK. But I was looking at the current draw
(again for the 480) and it doesn't draw much until you press the PTT
on the comm side.

Does not the 430 NAV section come up immeciately?

Maybe the VOR part does, but the GPS doesn't. And if you've been
navigating by GPS, the VOR might not be set as a backup, but instead be
set for something else.

But it's a good point, and a good reason to have the 430 VOR set to back
up any navigation to/from VORs. Of course, navigating by GPS direct
this may not be that often.

Jose
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

Put in a used KX125 as backup. I use it for atis/awos and monthly VOR
integrity checks.

Another option: purchase a portable GPS and portable comm to use as
backup. Only catch here is the difficulty of doing approaches.