ADS-B Configuration Choices

For more background, refer to my previous article, “ADS-B, What You Should Know” at

coveragemap3Above is a very cool ADS-B “buildout” map, courtesy of ForeFlight, showing the progress from 2/27/2012 to 6/27/2013. They are “getting there”.

The FAA expects to have ADS-B fully deployed by the end of 2013 or early 2014.

Do I need ADS-B? Only if you want to fly your Mooney after New Years Day, 2020 in airspace that presently requires an aircraft to have a transponder.

Will I need a panel installed WAAS GPS?

Yes. ADS-B will use your GPS location and transmit that information to the controllers. WAAS allows the accuracy needed and a portable GPS won’t do the job. So, if you don’t have a panel mounted GPS, let’s start from the least expensive options.

ebay has some used GNS 430 WAAS for sale at around $7,300, plus installation. A new Garmin GTN 650 will cost almost $10,000 plus installation.

Want a bigger screen? The Garmin GTN 750 starts at about $15,000 plus installation.

If you already have a non WAAS Garmin 430, then the upgrade to WAAS will cost about $3,200 plus two hours of labor to install the new antennae. Garmin does not service the non-WAAS models. However, Garmin will upgrade the non-WAAS 430/530 to WAAS. After that, your  GNS 430W or 530W are 100% supported by Garmin.

ADS-B “In” Goodies for those flying in the “Blue” areas depicted in the map above.

Can I receive weather and NOTAMs?

Yes. Flight Information Service-Broadcast (FIS-B) gives you FREE access to about the same information that is currently provided by a SirusXM Radio “Aviator” subscription:

  • METARs & TAFs
  • Non-Routine Aviation Weather Reports (SPECI or Special Report)
  • Both Distant and Flight Data Center (FDC) NOTAMs
  • AIRMETs and SIGMETs, including Convective SIGMETs
  • Special use Airspace (SUA) status
  • Temp Flight Restrictions (TFR)
  • Winds and temps aloft

FIS-B may soon receive more weather information, such as Lightning, Turbulence NOWcast, Icing NOWcast, Cloud tops, and 1 minute AWOS – all uplinked every 10 minutes. In contrast, XM’s data service packages can be seen HERE. To be fair, XM’s weather is more timely and, depending on the package, contains more analytical products.

But wait, there’s more!

Can I receive a traffic display in my cockpit, just like the big jets?

Yes, from the Traffic Information Service-Broadcast (TIS-B). The data link transmitter that commercial, biz jets and high performance / high altitude aircraft will use to report their position and altitude is a Mode S transponder that uses a feature called “Extended Squitter” (ES). These transponders transmit using the 1090 MHz band, which is the  international standard for ADS-B Output. A Mode S transponder with ES is required if you are flying in class A airspace (Flight Level 180 and above) or internationally.

Specific only to United States airspace – and not approved elsewhere – is the UAT data link transmitter, which is an alternative to the Mode S transponder. It transmits your position and altitude on the 978 MHz band. In 2020, UAT transmitters may only be used on GA aircraft that are flying below FL180 in the USA.

GDL-88 trafficAt left is a traffic display on a Garmin GTN 750. TIS-B will uplink to ADS-B “In” aircraft, allowing a traffic display in the cockpit. It will also display on a GNS 430 / 530.

How do I receive FIS-B and TIS-B?

There are two ways.

#1: Install a Universal Access Transceiver (UAT) in your aircraft. Only the UAT has the bandwidth to receive the FIS-B and TIS-B signals. (ES transponders don’t have enough bandwidth). Garmin’s UAT is the GDL 88 ($3,700 – $4,000 plus about 20 hours to install). The GNS 430W / 530W or the newer GTN 650 / 750 displays can present the data in the cockpit.

#2: Buy a portable FIS-B and TIS-B receiver. These connect either with Bluetooth or Wi-Fi to an iPad and power the applications:

The ForeFlight app works with the Stratus receiver. Stratus 1 sells for $700. It provides a Wi-Fi connection that allows ForeFlight to receive FIS-B. It also receives TIS-B (only ADS-B participating aircraft), using the 978 MHz band. That’s the band used by GA aircraft operating below Class A airspace.

Stratus 2 ($900) uses both the 978 MHz and 1090 MHz bands. This allows you to see ADS-B participating air carrier and private or commercial operators of high-performance aircraft as they “Squit” their location using ES Transponders. This makes the Stratus 2 traffic picture more complete. The Stratus 2 also features a built-in AHRS for backup attitude information and is 30% smaller, with improved GPS performance and better heat resistance. See the Stratus video HERE.

The Dual XGPS170 ($700) powers: AOPA FlyQ EFB, Avilution (Android app), Bendix King myWingMan, eKneeboard, Flight Guide iEFB, Naviator (Android app), WingX Pro7, and EFIS models from GRT Avionics. It connects to the iPad via a Bluetooth connection, providing FIS-B and TIS-B. Watch the Dual XGPS170 video HERE.

The Garmin Pilot app, works with the Garmin GDL 39 receiver ($700). It connects via Bluetooth, allowing the Garmin Pilot to receive FIS-B and TIS-B. It also supports portable Garmin GPS units like the aera and GPSMap. See a GDL 39 video HERE.

When it comes to receiving Traffic (TIS-B), it becomes a complicated mess that would thrill the Marque de Sade. You see, the concept behind ADS-B is that airplanes, using their WAAS GPS position, will report their position, altitude, speed and other data via a UAT or ES transponder datalink to FAA ADS-B ground stations. This is ADS-B Out. ADS-B compiles position reports from participating aircraft and crunching this data packet to a specific aircraft. That data shows where nearby aircraft are located, complete with relative altitude and target trends.

Without ADS-B Out, and using a portable ADS-B In receivers do a good job with weather (FIS-B), but they are fallible when it comes to traffic (TIS-B). Without ADS-B Out, you’re not a participant, so you are unable to receive a custom traffic packet. If there is a participating aircraft nearby, it’s your lucky day – you can see his traffic packet, but it won’t be centered on your airplane.

Portable ADS-B Receivers and TIS-B Traffic Displays – Three Scenarios

Stratus-no ADS-B groundScenario #1: You’re flying with a portable ADS-B receiver like the Stratus, GDL 39 or the Dual XGPS170, but you don’t have an ADS-B Out transponder like the Garmin GTX 330ES installed in your panel. You’re not near an ADS-B ground station, so you will only receive TIS-B target information for airplanes that are transmitting ADS-B Out via air-to-air.  (Most airplanes do not have ADS-B Out, but this will change after 2020 when the FAA’s mandate goes into effect.)

Stratus-no ADS-B-but close

Scenario #2: You are flying with a portable ADS-B receiver like the Stratus, GDL 39 or the Dual XGPS170 without an ADS-B Out transponder like the Garmin GTX 330ES installed in your panel.

You happen to be close to another aircraft that is ADS-B Out-equipped and within range of an ADS-B ground station. The ADS-B Out airplane can relay traffic information to your ADS-B portable receiver in a 30-mile bubble and in this case, you will see what Santa has broadcast to the ADS-B Ground Station. That is, you’ll see all in-range Mode C and ADS-B targets.


Scenario #3: You have an ADS-B Out transponder like a Garmin GTX 330ES  installed in your airplane. Using your installed ADS-B equipment, you’ll be continuously transmitting to the ground stations and creating your own bubble of traffic information. In this best-case scenario, you’ll see all radar traffic within a 30-mile diameter and 3,500 feet of your altitude on your iPad using portable ADS-B receivers like the Stratus, GDL 39 or the Dual XGPS170.

Scenarios – Thanks to Sporty’s

So ask yourself, “Where do I fly?” 

Let’s assume that you are equipped with a WAAS GPS, a Mode-C Transponder, and: 

           You desire to fly in Class A airspace or internationally after 2020, and 

           You want ADS-B weather and traffic displayed on the GPS unit(s) 

 Option 1 – FIS-B and TIS-B Panel Display. 

Upgrade to a Garmin GTX 330ES Transponder – $3,500 + about 4 hours to install. This satisfies the 2020 ADS-B out requirement. 330 INSTALL NOTES: If you are replacing a Garmin GNX 327 transponder, from the outside, it looks like a simple ‘slide out the old and slide in the new’ install. However, the GTX 330ES is 2.55 inches longer than the 327, so “some assembly required”. Good news: Both transponders use the same antennae. THEN . . . . . .  Install a Garmin GDL 88 Diversity Datalink – $3,745 – $4,000 + about 20 hours to install. This uplinks FIS-B and TIS-B data to your display(s).

OR . . . . If you already have a Garmin Data Link (GDL) for XM Weather, you can keep that. You will forego the TIS-B Traffic Display. XM Monthly costs depend on your desires. Click HERE for plans. See your Avionics shop for GDL install costs.

Option 2 ADS-B “In” FIS-B and TIS-B on a portable Garmin GPS or iPad OR keep XM Weather:

Upgrade your transponder. A Garmin GTX 330 ES Transponder will cost $3,500 + 4 hours to install. See 330 INSTALL NOTES in Option 1. THEN ADD . . . . . . .  An iPad or portable Garmin GPS units like the aera or Garmin Map696. 

The iPad starts at $400 for the 16 gig model. Wi-Fi models need an external GPS like the Dual XGPS150A or Bad Elf GPS – $100. The Garmin aera runs $600 and the Map696 costs $2,000.

Choose a portable receiver. This will allow you to receive FIS-B and TIS-B. Once again those receivers are the GDL 39 (iPad or Garmin portable GPS’), Stratus 1st Gen, Stratus 2nd Gen, (ForeFlight only) and the Dual XGPS170 (works with a myriad of apps)  OR . . . . If you already have a Garmin Data Link (GDL) for XM Weather, you can keep.  Monthly costs depend on your desires. Click HERE for plans. See your Avionics shop for GDL install costs.

Can a Garmin GTX 330 Mode-S Transponder be updated to ES? 

Yes. It can be upgraded to a GTX330 ES for only $1,200 + about 4 hours to install (see 330 INSTALL NOTES – previous page. If you’d like weather and traffic displayed on the GPS display(s), you’ll need to add a UAT, similar to the GDL 88 Diversity Datalink. Or, if you don’t mind viewing weather and traffic on your iPad, you can simply use the app and portable “ADS-B In” receiver options noted above.

Resale thoughts

If you own an aircraft that is capable of flying above FL180, but you choose to not equip your airplane with a Mode S (ES) transponder, consider this: One day you might want to sell your airplane. Without a Mode S (ES) transponder, you’ve handicapped your airplane a bit. It’s capable of flying high, but banished from Class A airspace. You will probably need to adjust your selling price accordingly.

Perhaps you have a normally aspirated Mooney that will never see Class A airspace. Being ready for 2020 makes your aircraft more exciting when compared, side by side, with one that needs some work.

If you:

Fly below FL180 and Have no desire to venture outside the USA and … 

Your aircraft is already equipped with a WAAS GPS and … 

You have either a Mode-C or Mode-S (non-ES) Transponder and … 

The idea of weather and traffic displayed on your GPS display excites you.

You’ll need to add just one piece of hardware in order to meet ADS-B requirements – a UAT.

Garmin’s UAT is the GDL 88 Diversity Datalink – $3,745 – $4,000 plus 20 hours to install.

Any Garmin GDL 88 model UAT will make an honest pilot out of you on January 1st, 2020. In the meantime, you’ll be able to enjoy ADS-B traffic (TIS-B) and subscription-free weather (FIS-B) on your GNS or GTS panel mounted GPS display. For more information, contact your favorite Avionics Shop.

Fly safe and stay out of trouble! JD

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5 comments on “ADS-B Configuration Choices

  1. Jackson says:

    A panel mount WAAS GPS is not required.

  2. Cesar Torres says:

    Dear jdpricecfi,

    Thank you so much for the information, it is awesome and answered all my question that I had about the Garmin units.

    Happy New Year!

    Cesar Torres
    Orlando Fl

  3. David Lane says:

    Dear JD Price CFI:
    I own a PA 28-140 1968 and have two old NavComss with Glideslopes that work just fine. I would like to comply with ADS B and have both in an out and use Garmin Pilot or Foreflight. My original plan included install of used 430W. The cost of used 430W and install is too much as I plan only a light IFR mission. (I am an instrument student)
    I would like to install GDL 88 with GPS installed along with Flightstream and Ipad. Alternate is Stratus ESG with ADS out only and Status portable with Foreflight. Will these configurations work. I understand that I cannot do hard IFR. Cost without 430W is $20,000 and without is $8600.
    David Lane

  4. plulos says:

    Excellent article; if you can add info, I’d add that if you want to share data with the Garmin Pilot app, with a GDL88 + Flight Stream, you can transfer flight plans back forth, weather, and traffic.

    Or you can be adsb out compliant only with a 330 upgrade to the 330ES that garmin says is $1200 + installation.

    Then you can add a GDL 39 (ADSB In) + Flight Stream for the Pilot app.

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