The safety of operating drones of any type in commercial airspace has drown a lot of attention and criticism of late, but the biggest threat remains other planes flown by humans. The FAA has a plan to improve operations and safety, but they haven't found a way to cooperate with Congress to finalize and implement it.
Three near-misses between commercial airliners have been reported since late April of this year. Interestingly, they've all involved United Airlines, but we'll chalk the airline affiliation up to coincidence. On April 24th, a United 737-800 on arrival to Newark from San Francisco nearly collided with a United Express Embraer ERJ145 that had just departed for Memphis, coming within 400 vertical feet and 160 lateral feet according to the NTSB.
The following day, April 25th, a United 757 which had departed from Kona, Hawaii for Los Angeles when its Traffic Collision Avoidance System (TCAS) went off, forcing the pilots to dive the plane 600 feet, because they were in the path of a U.S. Airways flight inbound to Kona. They came as close as five miles apart, but heading toward each other at cruising speed, that gave them roughly 30 seconds before potential catastrophe.
The latest reported close call was on May 9th in Houston, as two United Airbus A320s had each departed Bush International Airport. Air Traffic Controllers had inadvertently put the planes on the same course, allowing them to get as close as 400 vertical feet and 4,593 feet laterally. The correlation between these three events seems to be guidance errors from Air Traffic Control.
In an age when much of what happens in the cockpit is automated, air traffic control is still very much a manual process. In 2003, Congress mandated that the FAA establish the Joint Planning and Development Office, as part of the Century of Aviation Reauthorization Act, with plans to carry out and implement NextGen by 2025. The FAA NextGen project aims to completely revamp the national ATC system, but has continued to face delays. According to the FAA:
The movement to the next generation of aviation is being enabled by a shift to smarter, satellite-based and digital technologies and new procedures that combine to make air travel more convenient, predictable and environmentally friendly.
As the nation's largest airports continue to experience congestion, NextGen improvements are enabling the FAA to guide and track aircraft more precisely on more direct routes. NextGen efficiency enhances safety, reduces delays, saves fuel and reduces aircraft exhaust emissions. NextGen is also vital to preserving aviation's significant contributions to our national economy.
A governmental audit released this year revealed the following problems with NextGen progress:
- Unresolved design decisions that will determine NextGen capabilities, timing, and costs.
- Plans for completion by 2025 at a cost of $40 Billion were "overly ambitious." The FAA has yet to develop an executable plan that addresses costs and technology development and implementation.
Of the NextGen initiatives, only Performance Based Navigation has been implemented in Houston - site of the most recently reported near-miss. Required Navigation Performance (RNP) represents the latest in navigation techniques, allowing aircraft to fly precisely along a predefined route using state-of-the-art onboard navigation systems and the Global Positioning System (GPS) – resulting in reduced fuel consumption, reduced air and noise pollution, and increased capacity for airports.
One project, Automatic Dependent Surveillance - Broadcast (ADS-B) is finally in wide use nationwide.
[Illustration via ads-b.com]
With ADS-B, both pilots and controllers can see radar-like displays of traffic, provided by satellites. The displays update next to real time and do not degrade with distance or terrain like traditional ground-based radar does. The system also gives pilots access to weather services and flight information services.
Data Communication (Data Comm) is another part of NextGen, which seeks to replace the traditional analog communication between ground controllers and the flight deck, with digital methods such as messaging by text. Because vocal communication will be reduced, the potential of audio distraction to pilots is also lessened.
Storm at DFW [Caren Mack on Flickr, CC Commercial Use]
Common Support Services - Weather (CSS-Wx) will use data shared by the NextGen Weather Processor and the National Oceanic and Atmospheric Administration (NOAA) 4 dimensional Weather Cube to provide a unified weather "picture" to the entire ATC system. The FAA says weather is the cause of 75 percent of flight delays, and CSS-Wx is expected to allow everyone involved to collaborate and proactively plan around inclement weather, while also reducing controller workloads.
It should go without saying that these improvements to the national ATC system are much-needed. The plan was announced long before the current administration, but as with many initiatives, the age-old bickering within Congress continues to interfere with progress.
Top photo via U.S. Army Corp of Engineers, on Flickr with CC Commercial License