Before getting into the two halves of ADS-B, let me point out that only bureaucrats and propeller-head engineers could come up with a name like Automatic Dependent Surveillance-Broadcast. Don't you like how it just rolls off the tongue? Moving on, there's ADS-B In and ADS-B Out.
ADS-B In is simply the passive reception of traffic data sent from appropriately equipped aircraft and weather information broadcast from local, ground-based stations. ADS-B Out is more complicated (read expensive) for aircraft owners because it involves purchasing and installing new ADS-B transceivers that can transmit and receive GPS-derived position and altitude. The cost of equipping all aircraft with ADS-B is the big hurdle that seems to get glossed over, but such equipment will be mandatory for aircraft that want to use most controlled airspace by January 1, 2020.
In the meantime, there clearly is a void in traffic avoidance technology for light aircraft. Many GA aircraft have equipment that supports the current and useful TIS (Traffic Information System). Unfortunately not all ATC radar sites support TIS and when you're in those areas your TIS equipment will tell you traffic is unavailable. In classic FAA fashion, no sooner had TIS technology become widespread than there was the announcement that TIS would be phased out at some indefinite point in the future (back in 2005, the phase-out was said to be in 2013).
TIS is very useful and has saved my bacon on many occasions. Lately, some local controllers have gotten irritated when instrument pilots practice holding at some airway fixes. One fix in particular has been used by yours truly for holding practice over a decade, but we're now told to practice holds much farther to the East where there is supposedly less traffic. The irony here is that we're often flying TIS-equipped aircraft and in the area we've been asked to avoid we get TIS alerts and visually acquire the traffic, often long before the approach controllers point them out. When we hold further East as requested, we're in an area where ATC's radar does not support TIS, we actually experience more traffic conflicts, and we have to resolve these with just our eyes. To my mind, some procedures that are implemented in the pursuit of safety actually end up decreasing safety.
|GNS 5890 USB Stick ADS-B Receiver|
My firsthand experience with ADS-B was nil until the kind folks at Global Navigation Systems (makers of the GNS5870 bluetooth GPS receiver) recently allowed me to test-drive their new GNS 5890 ADS-B Receiver USB-Stick Receiver. This receiver comes with Windows software that allows you to display the position of ADS-B Out equipped aircraft on a map. The software itself is pretty simple and more a proof-of-concept than anything else. This device is small, purportedly the smallest ADS-B receiver made. And GNS has plans to release a Bluetooth ADS-B receiver with weather capability that could be very useful with the iPad, provided iPad EFB software developers introduce support for ADS-B Bluetooth devices. A combination ADS-B/GPS Bluetooth receiver would be an ideal solution. If the hardware and software align, ADS-B on the iPad could become a very useful, cost-effective, and subscription-free alternative to XM weather.
In order for ADS-B traffic capability to become a reality, all aircraft will need to have ADS-B Out capability and that will require an appropriately certified (read expensive) transceiver installed in each aircraft. In short, ADS-B traffic technology just doesn't seem to be something that can be accomplished with a portable device and installing ADS-B transceivers in all GA aircraft will be a huge, expensive, and time-consuming undertaking.
In an imperfect world where safety often seems to take a backseat to cost, ADS-B is a cool and promising technology. In the meantime, I sure hope that the FAA's proposed phase-out of TIS will be delayed.