Charles in SC
Well Known Member
Can someone point me to a simple explanation of ADS-B and how to figure out what I will need to be legal? It seems that the more I read the confuseder I get.
Van's Air Force
Don't miss anything! Register now for full access to the definitive RV support community.
Trying to understand ADS-B
- Thread starter Charles in SC
- Start date
keijidosha
Member
Knowing what's in your panel and EFB will help guide suggestions.
If you never fly where mode C is required (over 10,000', class b and C, etc) then nothing is required. Otherwise, by 2020, you have two options:
1. Mode S-ES transponder plus an "approved" position source. "Approved" means it carries the appropriate TSO, or the manufacturer says it meets the TSO performance requirements. One of the manufacturer's must also state that the two boxes will properly work together.
2. UAT transmitter plus approved position source. Many UATs come with the position source built in. Some also have ADSB-in as part of the package.
ADSB-IN is not required. But if you want it, start by considering how you will display the traffic and wx data.
GalinHdz
Well Known Member
Charles,
From your signature, it appears that you are building a new RV-7. That simplifies the decisions. Just purchase a new 2020 compliant ADS-B transponder (1090 MHz). I recommend the Appareo Stratus ESG or the Garmin GTX335 (specify with internal GPS). The Stratus costs about $2800 and the GTX335 costs about $3000. Shop around for the best price. You will know that the transponder and GPS receiver must be compatible since they come inside of one unit. There may be other brands available now or in the near future. There will be two antennas to install: the transponder antenna and the GPS antenna. Be sure to read the installation instructions. I purchased a 19 inch GPS coax before reading the instructions that specified a MINIMUM of 10 feet.
You might be able to save money by purchasing a used transponder and an adapter (UAT 978 transmitter). But then you have two boxes and two transponder antennas to install and twice the chance of a failure and twice the weight and compatibility issues. And antennas have to be installed so far apart which complicates things.
From your signature, it appears that you are building a new RV-7. That simplifies the decisions. Just purchase a new 2020 compliant ADS-B transponder (1090 MHz). I recommend the Appareo Stratus ESG or the Garmin GTX335 (specify with internal GPS). The Stratus costs about $2800 and the GTX335 costs about $3000. Shop around for the best price. You will know that the transponder and GPS receiver must be compatible since they come inside of one unit. There may be other brands available now or in the near future. There will be two antennas to install: the transponder antenna and the GPS antenna. Be sure to read the installation instructions. I purchased a 19 inch GPS coax before reading the instructions that specified a MINIMUM of 10 feet.
You might be able to save money by purchasing a used transponder and an adapter (UAT 978 transmitter). But then you have two boxes and two transponder antennas to install and twice the chance of a failure and twice the weight and compatibility issues. And antennas have to be installed so far apart which complicates things.
Last edited:
Charles in SC
Well Known Member
I have a King KT76C transponder. After talking to the King people at Sun n Fun it seems like the thing for me to do is install one of their add on boxes. When I asked for a simple explanation of ADSB I was thinking about a nuts and bolts intro. I have never seen one in the flesh so to speak. Some of the things I wonder about are what shows up on the iPad screen. Does it show just traffic or does it substitute for your handheld or mounted gps? Where would you put an iPad? What if the iPad quits? Is an iPad an approved piece of avionics? Maybe these questions are moot points but I can think of a bunch of others.
Well, if you ask King they'll recommend one of their solutions. If you ask Garmin they'll recommend Garmin. If you ask..... You get the idea.
There is no simple explanation because it's complicated.
Although ADSB-OUT is what is required, your iPad questions relate to ADSB-IN. Depending on what IN box you buy, it may display traffic and weather data on a Garmin or GRT or Dynon display device. It may also display on an iPad with the correct software. Depending on the IN box you may need WingX, or Foreflight, or Garmin pilot.
