New ADS-B In Applications Will be Deployed in June
By Scott Dennstaedt | May 18, 2018
Pilots and crew now depend on having some kind of datalink service in the cockpit. It’s just about as ubiquitous as GPS is these days. These datalink systems can be certified systems integrated directly into the aircraft’s panel-mounted avionics as well as portable solutions. If you have a datalink solution for flight information services broadcast (FIS-B) in your cockpit, you’ll be happy to know (as we are knee-deep in thunderstorm season) there are six new weather products being broadcast starting mid-year in the lower 48 U.S. states.
Pilots have basically two choices when it comes to datalink weather. The two options currently available are those from a satellite-based system offered through SiriusXM and a ground-based system offer through the FAA’s FIS-B that is part of the “ADS-B In” cockpit advisory services. FIS-B transmits graphical NWS products, temporary flight restrictions, and special-use airspace information via universal access transceiver (UAT) equipment on 978 MHz. Both options do require a hardware purchase, but only SiriusXM requires a subscription, making it more expensive in the long run.
Perhaps the most useful addition to the broadcast is lightning. Any weather that exhibits lightning will also be fraught with dangerous convective turbulence. It’s important to understand that the broadcast includes only cloud-to-ground lightning strikes. So don’t become complacent; many of the storms in the central plains, for example, have a 10-to-1 ratio of intra-cloud strikes to cloud-to-ground strikes where this ratio can become infinite for short periods of time in some severe thunderstorms.
Due to bandwidth limitations, you won’t get the position of every cloud-to-ground lightning strike that occurs. Instead, you will get a gridded pattern of lightning strikes at a 2-km resolution with the number of strikes in that grid is being passed along as well in the broadcast.
This is a 1- or 2-hour forecast of the icing condition that includes probability and severity. You may know this as the Forecast Icing Product (FIP) found on aviationweather.gov. The most significant issue with this product is its age. It’s only refreshed once each hour (although it is transmitted every 15 minutes). When the latest update is received, you will stare at that same image for another hour. Icing can be very transient at times, and it’s likely that an hour-old forecast may not be very relevant.
You may know this as the Graphical Turbulence Guidance (GTG) product found on aviationweather.gov. It provides an aircraft-independent forecast called eddy dissipation rate (EDR). An atmosphere that’s dissipating eddies quickly is one that is turbulent. Aircraft class is essential to use EDR. Similar to icing, it’s a 1- or 2-hour forecast, but only extends up to FL240. It’s transmitted every 15 minutes, but will only be updated once each hour and has the same issues with age as the icing forecast.
These are known as G-AIRMETs. They are not just a graphical depiction of an AIRMET. In fact, the textual AIRMET is now a byproduct of the G-AIRMET forecast, which has no associated text, just some metadata. Like the retirement of the area forecast last October, the AIRMET is also on the chopping block. So broadcasting the G-AIRMET in place of the AIRMET is just one step in a forward direction to reduce the dependency on the legacy AIRMET so it can be retired.
Since March 2010, the G-AIRMET has been the primary operational product issued four times a day by forecasters at the Aviation Weather Center (AWC). The legacy AIRMET is a time-smeared forecast valid over a six-hour period. This created some very large and not-so-useful en route advisories for turbulence, icing and IFR conditions.
Conversely, the G-AIRMET consists of five snapshots, each valid at a single time to include the initial snapshot and four forecast snapshots valid in 3, 6, 9 and 12 hours from the valid time of the initial snapshot. Therefore, each snapshot defines the coverage of that particular aviation hazard (e.g., icing) at a particular time creating a better and more useful spatial and temporal resolution. If you are wondering, text for the legacy AIRMET is still automatically generated by taking the union of the first three G-AIRMET snapshots (initial, 3 hours and 6 hours).
Center Weather Advisories
Center Weather Advisories (CWAs) are issued by meteorologists at the Center Weather Service Units (CWSUs) located at the Air Route Traffic Control Centers (ARTCCs) throughout the country. Like SIGMETs, they are not scheduled and are issued only when conditions warrant. I have always been perplexed why CWAs were not already one of the products broadcast since they have such a short lead time and are usually valid for no more than two hours. In other words, they represent more of a NOWcast rather than a forecast and describe conditions that are evolving as you are flying to your destination.
CWAs are issued in concert with existing G-AIRMETs and SIGMETs. They can be issued whenever an area of weather develops that is dangerous but doesn’t meet national SIGMET or G-AIRMET criteria. Also, they can be issued to augment an existing G-AIRMET. For example, a G-AIRMET for IFR conditions advises a pilot about the potential for widespread IFR conditions (visibility below three statute miles and ceilings less than 1,000 feet). However, CWAs are often issued within the bounds of an IFR G-AIRMET when there are a significant number of airports reporting low IFR conditions (visibility at or below one statute mile and ceilings at or below 500 feet).
Knowing the cloud tops is likely the holy grail of aviation weather. But don’t get too excited here. These cloud tops are not based on observations such as those you can get from infrared satellite data. Instead, what you will see is a one-hour forecast from the high-resolution rapid refresh (HRRR) model. This may do reasonably well with stratiform or nimbostratus tops, but not so well with areas of moist convection such as a broken field of cumulus clouds or even cumulonimbus clouds.
Equipment designed for safer skies
By Stuart Hirsch | The Herald Bulletin May 25, 2018
ANDERSON — Two small antennas on the roof and a nondescript, black, brick-sized box nestled in the computer hardware cabinet at Anderson Municipal Airport offices isn’t much to look at.
But it promises to make flying a lot safer.
The equipment is part of new aircraft tracking technology installed at the airport earlier this month called automatic dependent surveillance-broadcast, or ADS-B.
Instead of using ground-based radar and radio communication with their known limitations to keep airways safe, ADS-B uses more precise satellite navigation to broadcast an airplane’s position.
And it’s a key component of the Federal Aviation Administration’s Next Generation Air Transportation system modernization of the National Airspace System, which began in 2007.
By 2020, all commercial aircraft and, with a few exceptions, the owners of private planes will have to install the system in their aircraft, according to the FAA.
Anderson was able to install the ground-based part of the system two years early and at no cost because airport officials agreed to host the system here, said Brian McMillen, airport manager.
He demonstrated how the system works last week.
“Through the magic of electronics, the information is broadcast over the internet, and it comes out on the (computer) screen,” McMillen said. “Not only does it come out over the internet, other aircraft that are already participating in ADS-B can see it as well.”
During the mid-morning demonstration, McMillen said there were more than 3,700 planes airborne across the nation. By zooming in on the airspace around Anderson and clicking on a plane icon, he could tell the direction, speed, altitude, origin, and destination of each aircraft in real-time, with position accuracy of plus-or-minus 5 feet.
The fancy turn of phrase aeronautical folks use for this information is “situational awareness.”
For the rest of us, it’s as simple as knowing where the other guy is, and making sure they know where you are so both planes don’t arrive in the same airspace at the same time.
“Sometimes I’ve looked at this and it said upwards of 5,000 planes were in the sky at the same time,” McMillen said. “That’s almost staggering.”
But the platform is built to grow.
In 2016 there were just under 200,000 privately registered aircraft in the United States, according to the FAA, and almost 594,000 pilots.
Some private business groups raised concerns about the level of detail available with the system, arguing that competitors could use it to their advantage, but McMillen is skeptical.
“It’s not designed to see who’s going where, it’s designed to see who is where, and how aircraft can avoid other aircraft,” he said. “It’s a safety thing … It’s geared to stop mid-air collisions. The FAA is leveraging technology to make things a little safer.”
McMillen believes the April 2 crash at Marion Municipal Airport in which Elwood residents Kyle Hibst and David Wittkamper died might have been avoided if both planes had been equipped with ADS-B equipment.
The pilot of the Cessna 525 Citation Jet told National Transportation Safety Board investigators he never saw the smaller Cessna 150 carrying the two Pipe Creek Township volunteer firefighters attempting to take off.
Hibst was piloting the Cessna 150 when it collided with the tail section of the jet at the intersection of two runways, according to the preliminary report issued by the NTSB.
DOT Watchdog To Review ADS-B, NextGen Equipage
by Kerry Lynch – May 18, 2018, 10:18 AM
Citing concerns that only a “small fraction” of U.S. aircraft operators are prepared for the FAA’s Jan. 1, 2020 ADS-B Out mandate, the U.S. DOT Office of Inspector General (OIG) will be conducting a review of equipage rates and plans for meeting that deadline. The House aviation subcommittee requested the audit that is now expected to get underway next month. It will have three primary objectives: determining equipage rates for ADS-B and other NextGen technologies, ascertaining reasons behind equipage decisions, and assessing the FAA’s and operators’ plans to meet the ADS-B Out deadline.
Implementation of NextGen is a complex undertaking that requires investments from both the FAA and airspace users for the full benefits to be realized, the DOT OIG acknowledged. The FAA has put the ADS-B ground infrastructure in place but, with the ADS-B deadline fast approaching, only 48,000 of the estimated 241,000 affected aircraft are equipped.
The joint investment is true not only for ADS-B but also for systems such as Data Communications (DataComm) digitally linking controllers and pilots, the DOT OIG added. Besides putting the ADS-B ground infrastructure in place, the FAA has implemented the datalink technology at towers and is planning to implement DataComm at high-altitude facilities starting next year.