As we are all aware of (or certainly should be aware of), the January 1st 2020 mandate is rapidly approaching, now just a scant eleven months away. While a lot of aviators have been reaping the benefits of ADS-B “In” via inexpensive devices available from Amazon, the “Out” function is not nearly so easily acquired. That is, however, a different discussion for a different time. The crux of this matter pertains to a recent decision by the FAA to drop the requirement of ADS-B “Out” equipped aircraft to apply for Reduced Vertical Separation Minimum (RVSM) authorization.
To understand the significance of this latest determination by the FAA, you need to go back a little over thirty years in history. RVSM was essentially a means to better utilize vertical spacing on busy jet routes at higher flight levels. This was particularly important in Europe where real estate is at a premium in the very busy skies.
Back in the 1950s, standard vertical separation was 1,000’ from the surface up to FL290 (29,000’ MSL), and then 2,000’ above that. The reasoning? Pressure altimeters were standard, and while they have proven highly reliable, they are not precise to the point that you could reliably keep traffic closer than that at high altitudes. There were no Traffic Collision Avoidance Systems (TCAS), no Air Data Computers (ADCs), and autopilot systems were essentially two-dimensional.
As technology improved dramatically, efforts doubled down to create ways to reduce vertical separation because the skies were getting crowded quickly. A legitimate need was in the air for methods to reduce vertical separation.
RVSM Requirements, and the Changing Tech Terrain
In order to employ RVSM, each aircraft must meet certain equipment requirements which are laid out for U.S. operators in FAA Advisory Circular 91-85A. Since RVSM is designated as a special navigation area of operation, not all aircraft must be certified for it. However, that list of allowable aircraft for RVSM navigation will expand substantially with the passing of the final ruling approving the use of ADS-B Out in Support of RVSM Operations, which is effective as of January 22nd, 2019.
Without going into fine details of RVSM requirements, it should be understood that the process was/is a significant burden to owners and operators, and it has never been a “rubber stamp” approval. With the passing of the NEXGEN mandate, though, there became significant duplication of requirements between ADS-B Out equipped aircraft and RVSM requirements. The ADS-B Out mandate affects a much broader cut of aircraft as a whole, and is considerably less costly to implement than RVSM guidelines yet ADS-B Out must provide essentially all of the same data and is being required of any aircraft which intends to fly in controlled airspace beyond class E (again, this is a BROAD overview of the ruling, CFR 91.225).
Proposed Ruling-August 7th, 2017
This is an important component of the overall discussion since it represents the point when the FAA acknowledged duplication of efforts between ADS-B Out mandatory requirements and existing RVSM authorization requirements. As with all things inherently bureaucratic, it took fifteen months to decide on a common-sense approval; common sense is not always a common virtue.
An interesting excerpt from the executive summary explains how RVSM requirements first came about twenty years prior in 1997, mostly due to lack of familiarity with RVSM as a whole. This is the point when the FAA determined it required the legislative touch, creating a costly and difficult process in its wake. Technology has shaken the aviation industry like nearly all other markets, providing infinitely more user friendly interface and much more reliable equipment at a fraction the cost of the enormously costly modifications necessary just two decades ago.
Final Ruling & Approval-December 21st, 2018
We really can attribute the tech revolution with providing solutions to begin lowering the cost of air travel. Rather than having to field an entirely different avionics suite for aircraft wishing to use RVSM, the technology being installed in a Bonanza contains everything necessary to utilize RVSM. Rather than the millions of dollars it would have taken two decades ago, ADS-B Out equipment is measured in very reasonable thousands for capabilities which far outshine RVSM equipment from the 1990s.
Added Benefits: Much Wider Utilization of RVSM
Considering everything from Cessna Skyhawks and up are now equipped with ADS-B Out, RVSM is much more accessible now than ever before. Should a pilot with a suitable aircraft wish to utilize RVSM, they can do so now. This does not necessarily benefit major airlines much because their fleets were modernized since the RVSM implementation went into effect on January 20th, 2005. However, this may prove a real boon for private and charter jet owners and operators who wish to tap into the fuel reduction savings afforded by RVSM navigation.
Summary and Conclusion
The final ruling on docket FAA-2017-0782 will not affect much of general aviation; RVSM only exists above FL290 which is out of reach for most turboprops, let alone piston aircraft. But it could be groundbreaking for small charters who operate a single aircraft or very small fleet and could not absorb the cost of RVSM implementation but will get it ad hoc due to ADS-B Out implementation which is far less costly and administratively laborious.
The ruling went in effect just days ago, on January 22nd, so anyone upgraded to ADS-B Out (which is almost everyone at this point) with the reach and pilot training for RVSM can now utilize it. Remember, this ruling is for aircraft equipment, not pilot training.
Take into consideration that this is the FL500 view of this ruling, as well as the original RVSM implementation.
To find out more about gaining approval for ADS-B Out operations outside of the U.S., click here.