Page 24 - April21T

From the Flight Deck
by Kevin R. Dingman
Sliced Bread
Performance Based Navigation
Performance based navigation (PBN) provides for designing and implementing automated flight paths. It will facilitate improved access to airspace and runways, enhanced safety and reduced costs.
Using a machine invented by Otto Rohwedder, a Missouri- based jeweler, the first auto- matically sliced commercial
loaves of bread were produced by the Chillicothe Baking Company on July 6, 1928. The popular idiom “the greatest thing since sliced bread” means that something is “the best and most useful innovation or development invented for a long time.” The first use of the expression is commonly attributed to Red Skelton, who used it to describe TV in 1952. NextGen is about halfway through a multi-year implementation plan, and the FAA plans to introduce technologies, procedures and policies through 2025 and beyond. This mod- ernization of our air transportation system is “the most useful innovation
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or development invented for a long time.” It’s like sliced bread for pilots.
You gotta be very careful if you don’t know where you’re going, because you might not get there.
– Yogi Berra
The introduction of the VOR (Very High Frequency Omnidirectional Range) was air navigation’s previous sliced bread. No longer did we need VMC or scud-running in order to use lighted airways or ground markers. A VOR ground station uses a phased ar- ray antenna to transmit a directional signal that rotates clockwise 30 times
a second. They’re assigned radio chan- nels between 108.0 MHz and 117.95 MHz with the first 4 MHz shared with the ILS band. We started with relatively inexpensive “Low” VORs followed by the more useful but costly “High” VORs.
A worldwide land-based network of victor airways below 18,000 feet, and jet routes at and above 18,000 feet, was created. From the mid-1940s to the turn of the 21st century, VOR and Distance Measuring Equipment (DME) were the predominant navi- gational aids. “Area Navigation” began with LORAN-C in 1957 and OMEGA in 1971. The first aviation-specific Area Navigation systems (circa 1968, i.e., Narco CLC-60, King KNS-80 and
Typical RNP and ANP (Actual Navigation Performance) at cruise altitude.