Fllight Recorder Wars, Part II: What Backup to Use?

Hi Chip,

You mentioned below that you have questions about the future of CAI. That
is understandable, given the changes over the last 2 years. I was at first
very hesitant to work with the new company, but I have been impressed. They
ship products quickly and have done repairs as well. Gary Kammerer answers
technical questions in a timely fashion. The quality of the products seems
very good. I haven't had any returns.

Who knows what the future holds for any company. I wouldn't be selling
their products if I wasn't comfortable with the future of CAI.

Good Soaring,

Paul Remde
Cumulus Soaring Supplies


"Chip Bearden" wrote in message
om...
Good comments so far. Thanks. A few points:

1. The backup device MUST produce a log that's acceptable for U.S.
regional and national contests. As I read the rules, a handheld GPS
receiver is acceptable--even for a U.S. nationals--so long as it logs
altitude; a PDA-based system with a GPS card is not.

2. The most likely failure mode may well be a power problem, but I've
already got a backup power supply (that I've used 3 or 4 times over
the past 30+ years for genuine failures).

3. Regarding failure of the flight recorder:
a) the probability may be low but it's already happened once (the
UART comm. chip, I was told); to date, that's at least as frequent as
a power supply failure on a per hour or per flight or per year basis
b) the EFFECT is disastrous; if I'm going to drive halfway across
the country and spend the money to enter a nationals, I don't want to
zero a day because some $2 part fails. That's like tossing a live .45
caliber shell into a bin with 99 blanks, mixing them up, then picking
one at random, loading it into a pistol, aiming it at my head, and
pulling the trigger. The percentages are in my favor but the
consequences of that 1% chance are severe.

4. I can live without certain navigation and flight computer features
(I still carry a current sectional and a cardboard final glide
calculator) but if there are several alternatives and one allows me to
switch the source of GPS info for my LNAV and PocketNAV from my
Cambridge 20 to the backup device quickly and easily, it makes the
choice easier.

5. Gaps of up to 15 minutes are allowed, as are multiple incomplete
flight logs. So there is time to switch from one device to another so
long as (i) the primary flight recorder retains the flight log for the
portion of the flight preceding the failure point (not true,
apparently, when mine failed last year) OR the backup device has been
logging the flight from takeoff.

To date, Paul Remde's suggestion of a Cambridge 302A sounds easiest
(though not cheap). But that raises the same questions about
Cambridge's long-term (or even short-term) survival as were discussed
on this forum last year. What's the latest?

Chip Bearden

I would like to add to Cambridge Service - Gary Kammerer is
outstanding and always seems to get to the bottom of problems. The
ideal situation would be Dave Ellis (with Phil S) or whoever working
on new instrument developments. The new 302A CFR does look good and I
believe will have a black case and "camera mount" 1/4 nut atached real
soon.
Ian McPhee
Australia

Hi Chip,

I have a biased opinion. I sell the Cambridge 302A GPS/logger. It is a
very nice unit. The price is the same as the VL and Colibri but it has much
more memory for flight logs (100 hours at 4 seconds) and waypoints (1500).
I've also been told by the UK Cambridge dealer that the 302A works great
with the L-NAV. I haven't tried that because I don't have my L-NAV anymore.
If it's true then the 302A is the only logger that would send destination
airport elevation to the L-NAV. That is a very nice feature. It would
therefore be possible to wire a switch to use either the GPS-NAV or the 302A
for input to your L-NAV.

Alternatively, the 302A can be used as a "dumb" logger. It requires only
the 12V connection and it will log for most or all of your soaring season.

The only disadvantage to the 302A is that it is a bit larger than a Colibri.
However, unlike a Colibri it can be mounted very nicely in a 57 mm
instrument panel hole.

I have them in stock for $895.

Good Soaring,

Paul Remde
Cumulus Soaring Supplies
http://www.cumulus-soaring.com


"Chip Bearden" wrote in message
om...
I'm currently using a Cambridge LNAV, a GPS/NAV model 20, and Pocket
NAV on a Compaq 1530. Last summer, I experienced my first flight
recorder hardware failure just before (thank goodness) a contest. So
I am looking at backup options. I'd like an add-on device; I have
neither the money nor the inclination for a complete
vario/computer/flight recorder transplant.

I've heard the arguments for/against various brands, technical
approaches, etc., for a primary flight recorder. I'm interested in
knowing what makes sense for a BACKUP GPS flight recorder that will:

1) act as a "dumb logger" (i.e., connect it to a separate battery,
switch on, and forget) for backup purposes

2) in the event of a failure of the primary flight recorder, could IN
FLIGHT be connected to my LNAV and/or Pocket NAV/Compaq WITHOUT
compromising the integrity of the record in the backup recorder. This
could involve swapping cables from one device to another (my current
GPS/NAV is accessible in the cockpit now) or making up a special "Y"
connector and/or switch.

I drove my LNAV with an early Magellan "fish finder" GPS receiver for
years before I bought the Cambridge flight recorder so I'm not averse
to carrying an independent backup flight recorder PLUS a cheap
handheld that could be powered up to provide GPS info to the LNAV
and/or PocketNAV for navigation.

Regarding navigation, I'm old fashioned enough that I can (and still
do) use a map. But today's start and finish cylinders, turn-area
tasks, stiff penalties for restricted airspace encroachment, and tight
final glides seem to demand some sort of moving map nav display.

Those of you who remember my tirades against manadatory flight
recorders years ago (despite assurances of their reliability) will
appreciate the irony of my predicament, as well as my reaction last
summer to (1) the technician's comment that he'd never seen my failure
mode before, and (2) the $350 repair bill.

My primary application is U.S. regional and national contests.

Will consider new or used. Thanks for any suggestions.

Chip Bearden

I've got a Cambridge GPS, GPS Nav, LNAV and Aero 1550 running CEGlide.
Here's my back-up plan...
Carry my old Garmin 12xl + cables to connect to Aero. Turn on Garmin before
launch.
If any of the Cambridge stuff fails, unplug Aero from Cambridge, & plug Aero
into the Garmin. Turn in Garmin at end of flight.
Garmin traces were acceptable @ regionals summer before last--don't think
that's changed.

Brent

"Chip Bearden" wrote in message
om...
snip
approaches, etc., for a primary flight recorder. I'm interested in
knowing what makes sense for a BACKUP GPS flight recorder that will:

1) act as a "dumb logger" (i.e., connect it to a separate battery,
switch on, and forget) for backup purposes

2) in the event of a failure of the primary flight recorder, could IN
FLIGHT be connected to my LNAV and/or Pocket NAV/Compaq WITHOUT
compromising the integrity of the record in the backup recorder. This
could involve swapping cables from one device to another (my current
GPS/NAV is accessible in the cockpit now) or making up a special "Y"
connector and/or switch.

I drove my LNAV with an early Magellan "fish finder" GPS receiver for
years before I bought the Cambridge flight recorder so I'm not averse
to carrying an independent backup flight recorder PLUS a cheap
handheld that could be powered up to provide GPS info to the LNAV
and/or PocketNAV for navigation.
snip