You probably know by now that most airplanes will have to be equipped with ADS-B Out by 2020 in order to meet the FAA mandate. Beyond that basic issue, though, there are still a lot of questions to consider. One of the first is 1090 vs. 978. That is, should you install an ADS-B Out transponder that works on the 1090 MHz frequency (sometimes called 1090ES) or the 978 MHz frequency (sometimes called a 978 UAT)?

There is no simple answer, and all ADS-B Out transponders perform the same basic function no matter what frequency they use. Both meet the 2020 requirement. But there are some important differences to consider, depending on the type of airplane you fly.

• What is the total installed cost? The cost of ADS-B Out hardware is only one part of the equation – be sure to ask about the installation time and cost as well. 1090ES transponders are mounted in the avionics stack, in place of an existing Mode C transponder, so they don’t require the removal of the interior like most 978 installations (which are typically mounted in the tail of the airplane). In many cases, the installation cost is 30-50% less for a 1090 solution.
• How old is your Mode C transponder? In addition to ADS-B Out, you’ll still need to have a traditional transponder after 2020. If your existing Mode C transponder is on its last legs, a 1090ES transponder is probably the right answer, since it checks both boxes. In addition to meeting the mandate, you’ll get the features of a new transponder, like a clear digital display, push-button code entry and a dedicated VFR button. 978 requires you to maintain your existing Mode C transponder, so if you already have a new one you may be able to save money with a UAT.
• How integrated is each solution? Some 978 UAT transponders require separate control heads to synchronize the squawk code with your existing Mode C transponder – or even a separate panel-mounted indicator light. 1090ES solutions are integrated solutions: simply connect it to your existing transponder antenna and altitude encoder, then add a WAAS GPS antenna if a built-in GPS is included. The one exception is Garmin’s GDL88/84, 978 solutions that automatically sync with your Mode C transponder.
• Do you fly internationally? 978 UAT transponders are limited to use in the United States, so pilots traveling to Canada, Mexico or the Caribbean should choose a 1090ES transponder.
• Do you fly above 18,000 ft.? Aircraft equipped with 1090ES transponders are authorized to fly at all altitudes, whereas 978 UAT transponders are not permitted above 18,000 ft.
• What multi-function display do you have? If you have a glass cockpit or a modern navigator, a 978 UAT can display subscription-free weather and traffic on those beautiful color screen (if your 978 solution is an ADS-B In model in addition to Out). If you already receive weather and traffic with a portable ADS-B receiver, you can probably save some money by just choosing Out.

Mac McClellan, writing in EAA Sport Aviation, sums it up well: “If you plan to keep your airplane much beyond 2020, I think the new transponder route makes a great deal more sense… the 1090ES transponder install requires half the new antennas, no new cockpit panel unit, and a fraction of the wires.” On the other hand, if you have a glass panel, a remote-mounted 978 unit may make a lot more sense – especially if it’s done as part of a larger avionics upgrade.

Whichever ADS-B Out solution you choose, be sure to focus on the total installed cost of your new avionics. Read the fine print and ask informed questions about labor costs to install your new transponder and any additional parts that may be required. The right answer for you is the package that meets the 2020 ADS-B mandate, offers the upgrades your airplane needs, and is affordable to install.

The affordable, all-in-one ADS-B Out solution

For too long, ADS-B has been expensive and complicated. Not any more. The company that revolutionized ADS-B In with the Stratus series of portable weather receivers has done it again. Meet Stratus ESG, the affordable, all-in-one answer for adding ADS-B Out to your panel.

Benefits:

• ADS-B Out transponder meets the FAA mandate
• 1090ES technology – no altitude or geographic limitations
• Integrated WAAS GPS for an all-in-one solution – nothing extra to buy
• Includes new Mode C transponder – upgrade your old analog transponder
• Fits in standard transponder slots – typically 50% less to install than 978 models
• All mounting hardware and antennas included

Connect to your Stratus portable

In addition to being a great transponder and an ADS-B Out solution, Stratus ESG can also connect to a Stratus portable ADS-B In receiver. This makes it a complete system, with subscription-free weather and traffic.

• Get a complete traffic picture in ForeFlight
• Better ADS-B reception
• Better GPS reception
• Full-time power source
• Works with Stratus 2, 1S and 2S

Stratus ESG is made in the USA and includes a 2 year warranty.

For pilots who already have a WAAS GPS in the panel, Appareo also offers Stratus ES with the same features minus the GPS receiver.

S-TEC is the world leader in analog and digital autopilot systems. With the industry’s largest selection of single-axis, primary two-axis, and full-function two-axis autopilots, you’ll experience smoother, more stable flight and reduced maintenance down-time. S-TEC autopilots are STC’d for over 1,200 fixed wing aircraft models, and are installed on more than 35,000 aircraft worldwide.

Get ADS-B Benefits Today

• Dual-link Universal Access Transceiver (UAT)
• ADS-B “Out” solution for many aircraft
• Receives subscription-free weather and datalink traffic
• Optional SBAS/WAAS GPS
• Approved for installation in hundreds of aircraft models

The GDL 88 is the first dual-link solution for certified aircraft that not only provides a path to ADS-B “Out” compliance for many pilots, but also brings subscription-free weather and advanced traffic display to the cockpit.

Satisfy the ADS-B Mandate

Under the NextGen air traffic management system, all aircraft in controlled airspace will need to be equipped with ADS-B “Out” technology by 2020. For those who only fly below Class A airspace (18,000 ft) and in U.S. skies, the GDL 88 offers an affordable solution to reaching compliance. And even if you fly above 18,000 ft, the GDL 88 can still give you all the benefits of ADS-B “In” data – consider pairing it with a GTX 330/33 ES transponder for a comprehensive ADS-B “In/Out” solution.

With ADS-B “Out”, the GDL 88 gathers information about your position, track and ground speed from either your existing WAAS GPS source or an optional built-in WAAS receiver. It then broadcasts this information to ADS-B ground stations over the 978 MHz Universal Access Transceiver (UAT) frequencies. This gives ATC and ADS-B “In” equipped aircraft a more precise picture of what’s happening in the sky, and allows for more safe and efficient flight routing.

Take Advantage of Advanced Display Capabilities

TargetTrend™ technology (available on compatible displays) provides an easy-to-interpret picture of aircraft trajectories. When receiving ADS-B traffic information, this allows you to better predict potential conflicts. SURF technology also supports the display of ADS-B-equipped surface targets on Garmin SafeTaxi® airport diagrams – including taxiing aircraft and ground vehicles.

The advanced display capability of the GTN series avionics allows for enhanced functionality with the GDL 88. When there are several traffic targets in an area, the GTN will declutter the display by grouping the targets and showing only the one that is the highest priority. The pilot can touch a grouped target to ungroup and show all targets in the area. The GTN also allows the pilot to select any target on the display to view more detailed information including closure rate and ground speed.

Receive Traffic Alerts

You can still take advantage of the GDL 88’s ADS-B “In” traffic, even if you don’t have a compatible flight display to view the data. When installed in an aircraft without a compatible display, a visual indicator light can alert you when traffic enters your vicinity. Audible alerts tell of a target’s range, bearing and relative altitude (when available). You’ll hear this information through your cabin audio system in an ATC-like spoken format. For example, you might hear, “Traffic: 10 O’Clock, High or Low or Same Altitude, 2 miles.” In most cases, installing a GDL 88 with WAAS can provide a complete solution for ADS-B “Out” while still allowing you to receive some ADS-B “In” benefit — all with a single product.

Avoid Upgrading More Than You Have To

ADS-B requires your ADS-B “Out” source must squawk the same code as your transponder. Patent-pending technology allows the GDL 88 to be compatible with a wide range of general aviation transponders — synchronizing squawk code and ident to eliminate the need to install a dedicated UAT control panel.

Enhance Your Reception

Available antenna options allow the performance of the GDL 88 to be optimized for any type of aircraft. For optimal performance, a diversity antenna version with both top- and bottom-mounted antennas enhance the detection of traffic both above and below, and works to minimize radio blind spots caused by the wings or fuselage during aircraft maneuvering. This is especially useful in maintaining optimal reception of ADS-B weather and traffic during ground operations. A basic bottom-mount antenna version is also available as a more cost-effective alternative.

Aspen’s ATX200 dual-band in, 978 MHz out ADS-B transceiver is a solution for aircraft that have a Mode A/C transponder (or Mode S without Extended Squitter) and a WAAS-enabled GPS installed. The ATX200 is a certified solution and is compatible with Aspen Evolution PFDs and MFDs.

System benefits:

Access to subscription-free ADS-B weather and traffic for your Aspen display.

Meeting the FAA ADS-B out mandate with this solution:

With your existing Mode A/C transponder (or Mode S without ES) and WAAS GPS equipment installed, plus the ATX200, you will meet the mandate below 18,000’.