|
In summary the GTX-330 worked well and any traffic it displayed we were
able to visually verify. For someone used to flying with a BFG Skywatch,
or RYAN 9900B the first thing you will notice is the traffic is not always
available. With the Skywatch or 9900B, you get traffic the moment you
power up your avionics, and rarely loose coverage in flight. The GTX-330
is a data link, not an active system like the Skywatch or 9900B. Because
of this there will be times when the traffic feed will not be available.
That being said, the GTX-330 is still the correct choice for many pilots. The Skywatch and 9900B solutions are in the $17,000.00 + range and that is simply out of reach for some. The GTX-330 is in the $4000.00 range, and it's a great bang for the buck Peter Stelzenmuller |
|
One other useful/neat feature is the altitude monitor. As your flying
along, you hit the "FUNC" key on the transponder until the "ALT MONITOR"
comes up on the display. Then you hit the "Start Stop" key. The GTX-330n
stores your present altitude. As you wander above of below the altitude
the Garmin watches how far you have drifted from your initial pre-set
altitude. When you get move than 200 feet off, you get a verbal warning in
your headset "leaving altitude". The display on the GTX-330 continually
displays how far from your target altitude you are. In this picture the
GTX-330 is indicating we are 100ft above our preset altitude.
|
|
The traffic is getting busy around N10 so we head north. As we are in a
turn we notice a new warning on the screen "TRFC CST" "AGE 00:09". This
means that the GTX-330 has lost the T.I.S. traffic data. It continues to
display the last target and shows the age of the display. This will
continue for about 50 seconds. If the T.I.S. signal does not come back,
you will get a verbal warning "Traffic unviable", and you will get the
"TRFC UNAVAIL". This happened to us several time during our 1/2 hour
flight. Usually the traffic would come back within 60 seconds.
|
|
In the above example, there were no verbal warnings. The GPS was
displaying traffic on the screen, but the unit felt none of the targets
displayed were of immediate threat. This picture is about 30 seconds
later. The "OO" target from the last picture that was at 12:30 and our
altitude and was heading toward us has now created a situation the unit
wants to alert us of. Without pushing any buttons, a small dialog box has
appeared in the center of the screen. At the same time we get a verbal
call out in our headset saying "Traffic". The target that the Garmin
thinks is a threat has turned yellow. The display shows a 2nm and 6nm
ring. The yellow target is on the 2nm ring 100 ft above us, heading toward
us.
We visually identify the traffic outside and maneuver to the right. Pressing the "CLR" button on the GPS gets rid of the small dialog box. |
|
We do our run-up and take off. We level off at 1500 feet. In about 30
seconds the "TRFC UNAVAIL" warning goes away, and targets appear on our
GPS screen. The symbol is the same as with most TCAD systems. The target
has a two digit number that represents how far above or below the target
is from our aircraft's altitude. Garmin also adds a trend vector. This is
a predicted flight path for the target. In the picture to the right there
are three targets displayed. The map is on the 15nm ranges, so all the
targets are within about 5nm of us (you can zoom in or out to get a better
idea of the exact distance). The targets are:
1) At our 3:00 position at 200 feet below us, heading from right to left as viewed out our windshield. 2) At our 12:30 position at our altitude, heading toward us. 3) At our 9:00 position 2000 feet above us. heading to the left and away from us. |
|
Upon startup the GTX-330 will power up immediately. The unit is fully
solid state, and there is no warm up period. When you view your 430 or 530
screen you will see "TRFC UNAVAIL" (bottom right of center screen).
This indicated that the GPS and the GTX-33O are communicating, but the GTX-330 is not receiving any traffic data from the ATC facility. On the ground this is most likely because you are too low, and too far from the ATC facility for the T.I.S. data link to work. |
