Cambridge 302/303 users - feedback please

I have used a 302, without the 303, but with Glide Nav for several
years:

1.Reliability. 2 cases of internal seal failure otherwise no problems
2. Wind calculation - not done in 302
3. Good TE compensation no problem with over-read on thermal entry. I
use 1.7 audio and 2.3 vario and see good correlation with B40 readings.
4. Reads lower sink than B40 in cruise but never ran the numbers to see
if difference matched polar. No problem finding thermals in cruise.
Not an issue.

I did replace the display as I had one with incorrect polarization.
Not a reliability issue but a poor parts screening process.

Andy

I've had mine since late 2001 (302 only). It was jumpy and tended to
overshoot early on but Marty Eiler at Caracole worked some magic with
the plumbing and it now matches my B-40 in response as well as
strength. The only problem has been with the gear warning system which
failed intermittently and finally gave up the ghost (yes, we checked
the switches and wiring all the way to the connections on the 302).
Next time the unit comes out for calibration, I'll send it back to have
this checked.

I use it with WinPilot Pro and am quite satisfied. The 302 is the only
system I've used, so I can't be of any help on comparisons with others.

Ray Warshaw

Andy wrote:
I have used a 302, without the 303, but with Glide Nav for several
years:

1.Reliability. 2 cases of internal seal failure otherwise no problems
2. Wind calculation - not done in 302
3. Good TE compensation no problem with over-read on thermal entry. I
use 1.7 audio and 2.3 vario and see good correlation with B40 readings.
4. Reads lower sink than B40 in cruise but never ran the numbers to see
if difference matched polar. No problem finding thermals in cruise.
Not an issue.

I did replace the display as I had one with incorrect polarization.
Not a reliability issue but a poor parts screening process.

Andy

Andy wrote:
2. Wind calculation - not done in 302

The 302 does calculate wind, and it is used by the 303 and several third
party software packages. I've found it to be fairly accurate, but I'd
be a bit skeptical about what it's reporting after long periods of cruise...

Marc Ramsey wrote:
Andy wrote:
2. Wind calculation - not done in 302

The 302 does calculate wind, and it is used by the 303 and several third
party software packages. I've found it to be fairly accurate, but I'd
be a bit skeptical about what it's reporting after long periods of cruise...

Ok I suppose I should have said - not displayed by 302. In my setup
the wind is displayed by GNII on a PDA . Those winds estimates seem
reasonable but I don't know if GNII uses the wind data directly from
the 302 or computes its own wind estimate. According to the interace
spec the 302 sends the following wind info:

1 Vector wind direction in degrees
2 Vector wind speed in 10ths of meters per second
3 Vector wind age in seconds
4 Component wind in 10ths of Meters per second + 500 (500 = 0, 495 =
0.5 m/s
tailwind)

So it advises user systems how stale the wind estimate is. GNII does
not pass that info on to the pilot. Does the 303?

Andy

Marc Ramsey wrote:
Andy wrote:
2. Wind calculation - not done in 302

The 302 does calculate wind, and it is used by the 303 and several third
party software packages. I've found it to be fairly accurate, but I'd
be a bit skeptical about what it's reporting after long periods of
cruise...

I'm read, and it seemed to be the case while I was using GN II, the wind
will update when you change course by about 20-30 degrees for at least
10 seconds. I believe this is true for most glide computers that don't
have heading information available to them.

--
Note: email address new as of 9/4/2006
Change "netto" to "net" to email me directly

Eric Greenwell - Washington State, USA

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

I own a 302. I have had zero problems with it.

No 303. Instead of the 303 I use a PDA to give me moving map,
navigation, other soaring task information, thermal analysis, etc.

Some pilots use a PDA plus a flight computer's navigation display (like
the 303) so that they can be analyze two possible turn points at the
same time. They do this to help make real time decisions during
contests. That is an advantage of the SN10 as it also provides an
additional navigation display. Personally I have enough on my hands
watching one display.

The other thing to think about is cost. The Cambridge system is less
expensive.

- John