Flip Flop

January 21, 2020

This month’s title is not about a frequency switching feature in a Garmin, Avidyne, or Collins radio. This random set of thoughts is about exploring the equipment choices and operator’s behaviors with the equipment installed and NOT installed in their aircraft.

Succinctly, why do Part 91 and 135 Operators not adopt more SATVOICE capabilities and why don’t Part 121 Operators choose new graphical equipment like the fantastic new Avidyne Atlas touchscreen FMS with a NAV/COM and moving map for older, legacy aircraft?

It probably revolves around that one asset:  Capital. Money. Cash flow. Time = Money. Or, MANDATES, the main catalyst for airlines to re-equip their aircraft. 

We seem to get comfortable in our acceptance of avionics equipment and the functionality of that equipment. Look at a legacy, NG Boeing 737 FMS head unit today.  It seems to be the same as it has been for 20 + years, like the B777 panel image next to it.  


Boeing 737                                              Boeing 777

The same or a remarkably similar unit below is in legacy business aircraft like Gulfstreams, Global Expresses, Falcons, larger Citations, Embraers, and Challengers.

Honeywell FMZ-2000 in Business Jets

The Honeywell FMZ-2000 has been the FMS of choice for original equipment manufacturers (OEMs) for over 20 years.

Similar to a standard MS-DOS User Interface in the early 1990’s computers, there are now newer graphical user interfaces available in FMS boxes, and one, in particular, is even touchscreen.

Compare the FMZ-2000 screenshot to a newer idea above of an FMS for legacy aircraft.

There is even a cottage industry of phone and tablet apps to assist FMS learning and do recurring training for FMS units due to their complexity. How many times have you heard an airline pilot say, “I can fly an airplane, but that danged FMS takes some getting used to.”?

This Avidyne Atlas unit launched in late 2019 seems to have a remarkable amount of promise and Dan Schwinn, CEO of Avidyne is initially targeting legacy business aircraft. Some of the distinctions of the Avidyne offering are a QWERTY keyboard, the BIG one - a touchscreen interface, immense data capture for FOQA and maintenance purposes, optional NAV/COM built into the box and finally, all of this providing an order of magnitude improvement in situational awareness.   

From an FAA NextGen lens, the Atlas FMS checks all the alphabet soup boxes for Performance-Based Navigation (PBN):

  • Full Required Navigation Performance (RNP),
  • Area Navigation (RNAV) capability,
  • Including Localizer Performance with Vertical (LPV) Lateral Navigation/Vertical Navigation (LNAV/VNAV),
  • LNAV-Only,
  • And Approach Procedures with Vertical (APV) approach modes

Tables from the FAA’s PERFORMANCE-BASED NAVIGATION STRATEGY 2016 document, we see that there is an increase of 12% forecasted in RNP4 operational capability by 2025 and yet LPV approaches do not seem to be a priority for Part 121 operators. If they cared about those improvements to operational safety, equipment like the Atlas FMS could solve so much for older legacy aircraft.

This table is possibly skewed by newly delivered aircraft with those capabilities built into newer Boeings and Airbus aircraft. Maybe when all of these PBN modes are required by 2025 for the next version of NextGen, airlines will consider a more capable, much less expensive alternative to the standard equipment they are usually offered.

From the FAA website directly:

“In the midterm, navigation within the NAS will become increasingly PBN-centric, more resilient against GNSS service disruptions, and be supported by agile processes and tools for deploying and maintaining PBN procedures.”

So for one half or one-third of the price of current equipment to gain these PBN capabilities, Part 121 operators could have more than those older aircraft ever delivered about the aircraft, where it is, and how it is flown.  

That is not what Avidyne is pursuing initially, but we say, “Why not?”