Here are a couple of reasons why you might not want ADS-B
Quote:
Originally Posted by
jkgoblue
I have been contemplating this move and am excited about the prospects. I'm I to understand correctly that I will get the exact same weather displays on my 3500, ie, METAR's, TAF's NEXRAD, etc., that would with XM? And for free no less? Plus traffic! Is there any reason why I would want XM over ADS-B?
Thanks.
I can think of a few.
First, since ADS-B comes from ground stations which are far apart, you generally will not get ADS-B on the ground or at low altitude - including pattern altitude. So you may not reliably receive traffic targets from ADS-B OUT during the most critical portion of flight, departure and arrival, where the biggest chance for a conflict exists. That is a BIG negative for me. Forget about being able to sit in your aircraft on the ramp and checking for TFRs or enroute weather on a cross country, too.
Second, traffic, when it is received from ADS-B, is simply displayed on the screen, with no aural warning, and (I believe), no arrow showing direction of flight. So unless you constantly have your eyes glued to that screen, you may miss closing traffic. Compare this to the output from a Mode S transponder like the GTX-330, which provides both aural warnings and visible tracks on the screen showing direction so you can tell at a glance whether a target presents a conflict to your aircraft.
Third, ADS-B is not free, the transceiver from Navworx is $2700 (and you need the transceiver, not the receiver to reliably get traffic near you), while an XM receiver can be had for around a quarter of that price. It will take around 5 or 6 years for you to break even paying the XM subscription, buying the ADS-B receiver.
And fourth, the weather product received from the government is purported to be less feature rich than what you can receive from private sources like XM.
Just some food for thought. This is why I'm not excited about being an early adopter on this one.