Stratus™: Frequently Asked Questions

What is the source of the information received by Stratus?

The FAA's network of ADS-B ground stations is the source of the weather and traffic data received by Stratus.

Is there coverage in my region?

ADS-B has excellent coverage in most of the US above 1500 ft. AGL. See the map below for complete details.

ADS-B Coverage Map

  • Black dots indicate approximate tower locations.
  • In areas that are blue, Stratus should function well with only its built-in internal antenna at 1500 feet AGL and higher.
  • In areas that border the blue regions Stratus should function well with the addition of its available external antenna.
  • In areas that are gray, the Stratus will likely not function well at present. However, reception improves at higher altitudes.
At what altitude will I receive weather data?

The altitude Stratus begins to receive weather will vary depending on the number of nearby towers, terrain and the obstacles that may be between Stratus and a tower - it is line of sight. This can be on the ground at airports where an ADS-B station is on the airport, but in general, Stratus will start receiving weather between 500 and 1500 ft. AGL.

Are there any subscription fees associated with ADS-B weather?

No, there are no subscription fees and no registration required.

What weather products are available?

The Stratus receives: NEXRAD radar, METARs, TAFs, TFRs, SIGMETs, AIRMETs, NOTAMs, Pilot Reports and wind/temperature aloft.

What apps does this work with?

Stratus is built specificially for ForeFlight Mobile, so it offers deep integration and easy upgrades. The two are built as a system.

What versions of the iPad does this work with?

Stratus will work with all iPad models, but iPad 2 or higher (including Mini) is strongly recommended for best performance.

Can I get traffic information from Stratus?

Yes. Stratus 1S receives single band ADS-B traffic; Stratus 2S receives dual band ADS-B traffic. See below for more information about traffic.

Can I connect to the internet from Stratus?

No, Stratus is a one-way, receive-only device.

Can I receive satellite radio with Stratus?

No, Stratus is not equipped to receive satellite radio signals.

How can I improve my Stratus’s ADS-B reception?

ADS-B reception can vary greatly depending on the orientation of Stratus and its location in your aircraft. ADS-B is ground based, meaning the best mounting options provide an unobstructed view of the ground in your aircraft. Below are three mounting options that may improve your Stratus’s ADS-B reception.

Good: gel-base dash mount

Optional accessory for Stratus.

Ideal for: Pilots flying aircraft with unheated windshields in areas where there is full ADS-B coverage.

Tip: Place Stratus on the far side of your glareshield so that it is tipped outward and has the best view of the ground.

Better: suction cup mount

Included as standard with Stratus 1S and 2S.

Ideal for: Pilots who are not seeing continuous ADS-B coverage when flying in ADS-B fringe areas and those who want to mount Stratus off the glareshield.

Tip: To test if the suction cup mount would improve your Stratus's ADS-B reception, open the Stratus Status Page in ForeFlight Mobile while in flight and monitor the number of towers shown in the Receiving From field. Then rotate Stratus on its side and hold it to a window and see if the number of towers reported increases. Many pilots see dramatic improvement in ADS-B reception after moving thier Stratus to a side window of their aircraft.

Best: external antenna

Ideal for: Pilots who fly in areas with poor ADS-B coverage and those who want the flexibility to place Stratus virtually anywhere in the aircraft.

Tip: Don't worry if you can't see the LEDs on the Stratus. The same information is available on the Stratus Status page in ForeFlight Mobile.

Does Stratus satisfy the 2020 ADS-B Out requirement?

No. This is an ADS-B In only product. You will still need to modify your transponder or buy an ADS-B Out transmitter by 2020 to meet the upcoming FAA requirements if you plan to fly in airspace that requires a transponder today. 

One attractive option is Stratus ESG - the only ADS-B Out transponder made specifically for Stratus. This all-in-one solution, which includes a built-in WAAS GPS, meets the 2020 FAA mandate, offers improved reception and full-time power for your Stratus portable. It will also offer a complete traffic picture in ForeFlight. Certification planned for late 2015.

What is the range of ADS-B weather products? How far out do I see weather?

See AIM 7-1-11

Nexrad composite reflectivity (low resolution)Contiguous US
Nexrad composite reflectivity (medium resolution)250nm
AIRMETs100nm (airport surface); 500nm (en route/terminal)
SIGMETs and Convective SIGMENT100nm (airport surface); 500nm (en route/terminal)
METARs100nm (airport surface); 500nm (en route/terminal)
NOTAM (D) and FDC NOTAM (including TFR)      100nm
PIREPsNo airport surface; 500nm (en route/terminal)
Special Use AirspaceNo airport surface; 500nm (en route/terminal)
TAF100nm (airport surface); 500nm (en route/terminal)
Winds/temps aloft1000nm
How often is the weather updated?

See AIM 7-1-11 (transmission interval)

NEXRAD composite reflectivity (entire US)15 minutes
NEXRAD composite reflectivity (250nm regional)2.5 minutes
AIRMETs5 minutes
SIGMETs and Convective SIGMETs5 minutes
METARs5 minutes
NOTAM (D) and FDC NOTAM (including TFR)10 minutes
PIREPs10 minutes
Special Use Airspace10 minutes
TAF10 minutes
Winds/temps aloft10 minutes
Are there different types of ADS-B ground stations?

Yes, although in practice it doesn't really matter. You will usually receive many stations of all different types.

Station TypeRangeWeather Products Available
Low-altitude500nmWinds/Temps aloft
150nmregional NEXRAD
Medium-altitudeContinental USnational NEXRAD
750 nmWinds/temps aloft
200nmregional NEXRAD
High-altitudeContinental USnational NEXRAD
1000 nmWinds/temps aloft
all 158 Class B/C airportsMETAR/TAF
250nmregional NEXRAD
Is there a GPS in Stratus?

Yes, there is a GPS / WAAS receiver built-in to Stratus. You will see your airplane on all geo-referenced charts (sectionals, IFR en route charts and approach plates in ForeFlight Mobile.)

The non-3G/4G iPad has no GPS receiver in it. The 3G iPad has a GPS receiver in it but it is not WAAS capable and so provides less accurate solutions than Stratus will. In addition, the built in-GPS receiver in an iPad is subject to Apple power management and so it will have to reacquire the GPS signal every time you wake up your iPad. Because Stratus is always on, even when your iPad is sleeping, it will keep a constant GPS signal which will be available as soon as you wake up your iPad.

Is an external antenna required?

No. The GPS, ADS-B and Wi-Fi antennas are all internal. An external ADS-B antenna option is available for Stratus 1S and 2S, and an external GPS antenna is available for Stratus 2S.

Where can I mount the Stratus?

We recommend you experiment with different locations to find the best performance. Options include the glare shield, co-pilot's seat, or side window (using a suction cup mount.) ADS-B reception is based on line of sight.

Is there a battery?

Yes, the internal battery will operate the Stratus for approximately 8 hours. The unit can be powered in-flight using an optional cigarette lighter charger. A 110V AC wall charger comes standard with the unit to charge the unit prior to a flight.

Are there temperature limitations?

-20 degrees C to +65 degrees C. We recommend you do not place the Stratus in direct sun for extended periods of time, especially in hot weather. Treat it like your iPad.

How does ADS-B traffic work?

The most important thing to understand is that ADS-B traffic is not like ADS-B weather. The weather product (technically FIS-B) is broadcast to anyone with a receiver – like an AM radio station. The only real limitation is that you must be in range of an ADS-B ground station. This is what some people call a “dumb transmission,” because you simply turn on the receiver and start receiving radar, METARs and TFRs. No additional equipment is required.

ADS-B traffic (called TIS-B), on the other hand, is very different – it is not broadcast to anyone and everyone. Instead, it is a “smart transmission,” meaning the ADS-B ground station sends a customized data package to a specific aircraft, and only in reply to an interrogation from specific types of panel-mount avionics (ADS-B Out transponders like the Garmin GDL 88, Stratus ESG, etc.). If you don’t have the right panel avionics – and most airplanes today do not – you probably won’t get reliable traffic.

More Details

An aircraft that is equipped with ADS-B Out and squawking ADS-B will cause the FAA to send out a customized traffic product that is 30 nautical miles in diameter around the aircraft and 3,500 above and 3,500 feet below it. It is sometimes referred to as the “hockey puck” for obvious reasons:

ADSB Traffic Diagram

Let’s look at an example where you are in an aircraft that is not equipped with ADS-B Out, but your aircraft happens to be flying close to another aircraft that is (you are inside the hockey puck.) You can “listen in” on the ADS-B Out airplane’s traffic signal, and get a good display of traffic. But if you are close to the edge of the hockey puck, you may only see traffic on one side of you – remember, the 30 mile traffic display is based on the ADS-B Out airplane, not you.

Single Band vs. Dual Band

It’s also possible to see other aircraft air-to-air, meaning your Stratus receives ADS-B Out transmissions directly from other aircraft. In this scenario, there is no need for a ground station, but the other aircraft has to be one of the very few equipped with ADS-B Out. Aircraft equipped with ADS-B Out can transmit on one of two frequencies: 978MHz and 1090MHz. Stratus 1S receives only 978, which includes ground stations and 978 air-to-air targets. Stratus 2S adds 1090, to receive all ADS-B Out aircraft air-to-air.

If you have ADS-B Out in your panel, you will be receiving a high quality traffic picture from the ground stations, so this air-to-air reception is less important.

Is TIS-B the same as Mode S Traffic?

No. Mode S traffic (sometimes called TIS-A) was popular in the early 2000s, with products like the Garmin GTX 330. This transponder received traffic information from terminal radar approach control, transmitted via Mode S. But the only traffic you receive with Mode S is the traffic in your local TRACON coverage area, and you only receive this information when you’re close to the TRACON. In addition, not all TRACONs support Mode S traffic.

TIS-B, on the other hand, does not depend on a TRACON. You see all traffic, even from en route radar facilities and TRACONs that do not support Mode S. In addition, the data is transmitted via ADS-B ground stations, not local TRACONs, so it is available over a much larger area of the country.

Bottom Line

There’s no doubt this subject is complicated. Here’s the one thing that is easy to remember: if you do not have ADS-B Out installed in your panel, you will not get reliable traffic on your iPad. That doesn’t mean it’s worthless, just incomplete. Most often, you’ll see lots of air-to-air ADS-B traffic, which is usually airline and cargo jets. Use ADS-B traffic as supplemental information, but never as a replacement for a good visual scan. 

Read this article for more information, including a helpful graphic.

Can I dim the Stratus LEDs for flying at night?

Yes, you can dim or brighten the LEDs using the LED brightness slider on the Stratus status page within the ForeFlight Mobile app.

How can I check my battery level and reception?

This video tip offers some good information:

Can Stratus be placed upside down?

Yes, Stratus can be placed upside down without causing any loss of AHRS accuracy or problems with WiFi communication. This option is especially attractive in aircraft with limited dash space. If you are using Stratus for AHRS information, ensure that Stratus is mounted parallel to the aircraft’s centerline and the LEDs and Stratus logo are facing the back of the aircraft. Since the internal GPS antenna is located on the top of Stratus, you may see some GPS degradation. To remedy this problem, you can connect Stratus to the external GPS antenna.

What about portable ADS-B Out products?
ADS-B Out transponders must be certified and installed in the panel (Stratus 1S and 2S are ADS-B In only). The FAA is very clear: "Portable ADS-B Out systems, also known as ‘suitcase’ units, should not be operated (transmitting) aboard any aircraft. While marketing associated with these units may imply approval for use by way of an FCC license, the FAA prohibits their use."
What's the difference between Stratus 1S and Stratus 2S?
Stratus 1S and 2S share a lot in common: both receive subscription-free ADS-B weather, both include a WAAS GPS, both are totally wireless, both feature an 8-hour battery life and both work with ForeFlight Mobile. Stratus 2S adds dual band ADS-B traffic (Stratus 1S is single band, so not as complete a traffic picture) and a built-in AHRS for backup attitude information and synthetic vision. Stratus 2S also includes a built-in pressure altitude sensor and an automatic flight data recorder. Stratus 1S is $549 and Stratus 2S is $899.
Will Stratus’s battery charge if is both plugged-in and operating in an aircraft?
Yes, Stratus will still charge its battery when running but only if it is plugged into a high-capacity, 2.1 amp charging source and only if the battery temperature is between 0 and 40 degrees C. If it is plugged in but the battery is too hot or too cold, then Stratus may continue to operate but the battery will no longer charge - to protect it from damage.
Does Stratus work outside of the United States?
The GPS and AHRS features will work anywhere, so moving map and backup attitude are worldwide. But Stratus receives ADS-B data from ground-based towers broadcasting on UAT (978 MHz), and this service is not available outside of the United States.
Can more than one iPad connect to Stratus?
Yes. In fact, every iOS device running ForeFlight Mobile in the cockpit can connect to Stratus at the same time.
Does Stratus work with other applications? What should I do after my Stratus stops working properly after using an unsupported application?

ForeFlight, Sporty's and Appareo do not recommend or advise using the Stratus device with unsupported third party applications that have attempted to reverse engineer the interface.

If you do use Stratus with an unapproved third party application, the following instructions will be helpful in order to overcome the problems you are about to encounter.

  1. Reboot your iPad after using Stratus with the unsupported application and then re-connect to the Stratus network.
  2. Launch ForeFlight to resume normal Stratus operations.
  3. Do not activate the unsupported application while connected to Stratus, which would then require steps one and two to assure normal operations.

If you do attempt to use Stratus with an unsupported application, you will need to reboot your iPad after each use of Stratus with the unsupported application, and then re-connect to Stratus. Failure to do so has been shown to disable use of Stratus in some cases, among other issues. Unauthorized companies making claims that they "support" Stratus are in our opinion misleading. They are not endorsed or supported by AFS, LLC (the joint venture that makes the product, of which Sporty's is a member) and therefore we cannot confirm or verify any unsupported app maker's claim to deliver a safe and reliable experience.

Unsupported applications are known to:

  • Display inaccurate or incomplete ADS-B information.
  • Display inaccurate flight parameters (e.g. AHRS information).
  • Create a denial of service to Stratus functions.
ForeFlight does not show any traffic when connected to Stratus. How can I get traffic to show up on the map screen?
Traffic is a layer and must be activated in the ForeFlight dropdown menu. this layer only appears when connected to Stratus. Note: Until your plane is equipped with ADS-B out, your traffic reception will be fairly limited.

Still have questions? Email our team:

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