ADS-B Explained. Over the past years Airtronics has carried out ADS-B compliance upgrades for over 1,000 aircraft. We have seen the other shops pricing, and found the competition is usually 20% or more than Airtronics. Many other shops, much to our dismay do not carry out installations in accordance with the equipment manufacture’s approved installation documentation. Heck! Airtronics corrected an installation from another shop that scores the worst installation ever. The transponder tray was mounted with PK screws, required annunciation was missing, and the audio for traffic alerting was not connected. To top that the aircraft registration number was programmed for a plane that does not exist on the FAA registry. Sloppy…. So please beware. Talk to your friends and fellow pilots and get some recommendations.
Here we will explain ADSB requirements. First ADS-B is an acronym for Automatic Dependent Surveillance Broadcast. On Jan 1, 2020 the FAA mandated all aircraft operating in certain airspace and altitudes to be equipped with ADS-B out.
Aircraft ADS-B systems need to comply with 14 CFR part 91.227. What you will need to become compliant are a few simple elements. First a WAAS GPS position source that will transmit GPS 3D position. The 3D is vertical height produced by the WAAS (Wide Area Augmentation System), a GPS track, and GPS ground speed. Second you will need an uncorrected altitude source (standard pressure altitude at 29.92) such as an encoder or air data computer. The important item to note is that the source supplying altitude to the ADS-B transmitter must be the same source furnishing altitude to the transponder. Not doing so will result in ATC and perhaps you seeing multiple traffic targets. A target would be on your six and very, very close.. Bad news. Ever heard the traffic alarm in the background when talking to ATC? Chaos ensues!
The ADS-B transmitter is automatic. Meaning it does not require an interrogation by radar surveillance like a transponder does. The ADS-B system is always transmitting the ADS-B information. The system is programmed by the installer with the aircraft identification # such as US tail or HEX code. This is called the Mode S information. In addition the transmitter is programmed to broadcast the type aircraft, and some performance information like max speed, and weight class. The ADSB system will automatically broadcast the discrete Mode A code that is provided by ATC to the pilot.
ADS-B out systems are required to have a certified means of informing the operator of the aircraft that the system is in a fault or no fault state. The most simplest is an annunciator light labeled ADSB Fail. An STC manual or other approved installation documentation will list the minimum equipment required and approved interfaces for the installation. Systems that are incorporated in new transponders such as a Garmin GTX 3xx or Appareo ESG will flash a message status on the transponder screen to comply with this requirement.
The requirement for ADS-B does not eliminate the requirement for a transponder. 14 CFR 91.413 remains and a transponder is still required to broadcast a mode A (discrete assigned code) and Mode C (the uncorrected altitude) when interrogated by ATC.
ADS-B can be broadcast on one of two frequencies. If your light aircraft service ceiling is limited to 17,900 MSL you can use the UAT 978 mhz frequency for ADS-B. High performance aircraft that have service ceilings higher than 17,900 MSL are required to broadcast on 1090 MHZ frequency. Understand that those transmitting on the UAT are still required to have a transponder that replies to interrogation on 1090 mhz.
Now lets evaluate what is out there to chose from. Lets say you have a transponder and it is an older one like a Narco AT50, or King KT76A, and It still operates to factory spec, all you want to do is get out compliant, and your aircraft will never make it to 18,000 MSL. The only system we know of that just works is the Garmin GDL82. It is simple, in that it intercepts the existing transponder antenna cable and reads the altitude, (mode C) and discrete (mode A) code prior for transmitting on the UAT (978) frequency. The transponder antenna if a monopole will need to be changed to an L band such as a model AV-74 by RA Miller. The GDL82 is a programable remote mounted box with a built in WAAS GPS receiver. So you will need a location to mount an approved WAAS antenna with a clear view of the sky. It is a good idea to see your shop and have the existing transponder system tested prior to installation to verify the transponder is operating to manufacture’s specification. At Airtronics we have been furnishing and installing the GDL82 for $2,900 for most GA aircraft. Fabric and composite airframes have additional charges for the GPS antenna installation, but this is no doubt the least expensive, and trouble free solution to compliance.
If your current transponder is not operating per spec, and cost prohibitive to support, you then consider other options that accomplish both the ADS-B and transponder requirements. There are basically only two systems that qualify as The Airtronics solution meeting you need.
The lesser cost of the two ADS-B systems with a new transponder is the Appareo ESG. It is a certified 1090 MHz transponder with a built in ADS-B transmitter and carry’s on board a WAAS GPS for position. The upgrade should consider a new encoder for pressure altitude. After all if the transponder is due for a change, then why not do the encoder too. Encoders in general have a life expectancy of ten years or less. At Airtronics you can trade in your old transponder and have the Appareo ESG with a new Transcal SSD120 encoder for $4,500.00 for most GA aircraft. Again composite and fabric aircraft are slightly more for handling the mounting of the GPS antenna. Appareo offers an optional ADS-B in solution for your tablet that can be included with your installation. The Stratus receiver if you don’t have one can be purchased and coupled to the transponder to share the GPS and ADSB antenna. A great device that WIFI connects to your tablet and will display FISB and TISB information on a pilot Ap like Foreflight.
The other ADS-B out only system is the Garmin solution. The GTX335 with or without an internal GPS. If you do have a WAAS GPS such as a GNS480, GNS430/530 or GTN you won’t need the internal GPS option. This saves a little money utilizing it. In addition it is preferred that the GPS for navigation be the same for ADS-B position reporting. The GTX335 also comes in a remote mount version that can be controlled by a GTN or GNS480 navigator to save panel space. Airtronics has done many upgrades to cabin class twin aircraft that had legacy remote Collins and King transponders. It usually pays to upgrade to a GTN in the cockpit for WAAS navigation, and control of a remote transponder or two in the avionics bay.
The cost for the GTX335 and installation starts from $3,800.00 for a non GPS unit, and $4,800.00 for a GTX335 with internal GPS. A Garmin digital encoder module option is available for a $300 add on, and you can use your existing functional transponder antenna. Some aircraft such as pressurized, composite, or fabric skinned may have additional charges for antenna mounting.
Now lets talk the ultimate ADS-B solutions. After all the whole ADS-B system was designed and implemented for you the aircraft operator to have increased situational awareness. Gone are the days of the $20k plus traffic systems and $6k XM weather systems with subscriptions. Now you can get a system in the plane for as little as $6,500.00 that will display on many approved panel mounted as well as portable displays. Maybe you want to display on the Primary Flight instrument such as your Aspen or Garmin TXI, and simultaneously on up to four tablets. The GTX345 is the ultimate. The cost to trade out your old transponder and install the all in one GTX345 with integration to your Garmin WAAS GPS, MFD starts at $6,500. There is an optional internal GPS available usually adding $1,800 to the project if you do not have an approved WAAS position source. Airtronics charges an additional $300 each for additional wiring interfaces, and $300 if you want a new Garmin Encoder. Remote mount systems start from $7,000 and systems to upgrade G1000 are usually around $10k.
Another in solution available not to overlook is the Garmin GTX375. It is an affordable solution for operators that do not have or are ready for a WAAS navigator. The GTX375 is an internal GPS navigator, with an ADSB compliant transceiver and transponder built in. The GTX375 displays FISB weather, and TISB traffic received by its built in receiver. It will interface with many approved displays, and includes bluetooth connectivity to your tablet. VFR installations start at $9,200 and IFR installations vary depending on the interface.
At Airtronics we hope you don’t confuse us with the guys in Tucson, or Wisconsin. We are “The Airtronics”, The original since 1956, maintaining a leading reputation for our quality and service. We hear many talk up The Airtronics cockpit and ADSB upgrades on BeechTalk, Pilot’s of America, and more. Most ADSB upgrades are one day installs, and the cost is always as quoted. Thank you to all out there for letting Airtronics serve you. For all considering Airtronics, please don’t expect perfection, just know that we strive for it everyday.
If you are wanting to just talk shop about ADS-B or about ideas on designing your next panel upgrade, drop us a line. Airtronics has locations in California and Colorado as well mobile technicians to serve you . email sales@airtronicsavionics.com with your aircraft information for a quote today.
We are The Airtronics! Avionics by pilot’s for pilot’s and every mission!
