What’s the point of carrying a handheld radio if you have one (or two) radios installed in your panel? For that matter, why carry a paper sectional chart if you have a fancy glass panel cockpit or an iPad running ForeFlight or FlyQ?
Besides common sense, what’s the point in having a backup to your primary system?
It’s not like those traveling through Atlanta’s Hartsfield-Jackson International eight days before Christmas in 2017 were inconvenienced by a nearly 11-hour power failure that led to widespread panic, confusion, and more than 1,000 canceled flights. Never mind. That’s a bad example.
What about GPS? It is everywhere and drives everything. Do we need a backup for that system?
A Nov. 26, 2017, editorial in The Wall Street Journal, “If GPS Failed, We’d Be More Than Lost,” notes that 15 of the 18 Critical Infrastructure and Key Resource sectors in the U.S. are GPS-reliant, according to the Department of Homeland Security.
Yikes.
The editorial outlines a few potential threats to GPS, such as terrorism, signal jammers, and solar storms, and advocates for reinvigorating an existing land-based navigation system.
“Loran is a great backup system because its signals would be difficult to jam and it would be less exposed to celestial events.”
Interesting.
Looking more specifically at aviation, Maryland’s William Rynone says in a letter to Dorchester County Manager Jeremy Goldman, “The FAA is likely aware of this and for that reason the VORs and non-directional beacons (NDBs) have not been rapidly de-commissioned. An NDB used with Automatic Direction Finding (ADF) equipment is likely the simplest and least expensive transmitter used in any navigational system.”
I suppose Mr. Rynone would know. He taught electrical engineering at both the U.S. Naval Academy and Johns Hopkins University.
Rynone’s letter was written in response to plans to de-commission the NDB at Cambridge-Dorchester Regional Airport (CGE).
If the idea to shut down the NDB is about cost, Rynone estimates the monthly cost based on transmitter efficiency, as well as power supply, oscillator and power amplifier, at “$5.40 per month.”
“Summarizing, the de-commissioning of the NDB at Cambridge Airport does not seem to be justified since it does not appear to have any beneficial consequences, but does inhibit some pilots from using the airport.”
Multiple factors drove the decision to de-commission the NDB, according to Cambridge Airport Director Dr. Amber Hulsey. Cost is a huge driver, of course. The county is in the process of demolishing the airport’s old terminal building to eventually make room for new hangars, which is part of the airport’s master plan.
In preparing for that project, re-routing power to the existing AWOS, as well as re-locating, re-building and re-wiring the NDB, would need to be accomplished. Neither the state nor the FAA stepped up with financial support for the NDB. And with a finite amount of money in county coffers, it was decided to maintain the AWOS and de-commission the NDB.
Life is often about choices. With limited options, hard choices have to be made.
Another factor is usage. Hulsey said their research showed the NDB was used two to three times per year. Which makes sense, I suppose, considering GPS architecture is operational.
Mr. Rynone’s letter, I feel, was informational and educational, not adversarial. While his letter is likely more about him and his flying rather than the larger aviation ecosystem, I think it fits nicely into the discussion.
“CGE has the full support of the Maryland Aviation Administration (MAA), Federal Aviation Administration (FAA), consultants and regional airports,” adds Hulsey.
From my view on the other end of the country, Dorchester County did what it had to do. De-commissioning the NDB wasn’t done to cripple the airport or to spite someone, it was simply part of a larger project.
Hulsey said that when she learned to fly, “it was round gauges.” Yeah, me too, Amber. She then asked me how many of the myriad legacy navigation systems, which are rarely used, I felt should be maintained.
This isn’t about maintaining a specific number of legacy systems. It’s about a backup system. What’s the value to your business of paying thousands of dollars for off-site physical and digital storage of critical company data that never gets used…until it absolutely gets used.
Backup systems are crucial. Not just in aviation, but in society at large.
Should we put all our eggs in one GPS basket? I don’t think so.
WOW!, you guys must not be watching the 6 o’clock news. The NSA is using your portable phone, google maps, email and facebook to find you. The NSA uses many unrelated systems to follow your every move even underground.
Do a search of your typical smartphone tracking:
1. Cell tower triangulation
2. GPS receiver
3. Inertial Navigation – yes, there’s an APP for that.
4. IP address
5. Credit Card purchase
6. Voice and face recognition microphone/cameras at stop lights and public areas.
There’s most likely more that we don’t even know about. My custom agent friend has given radar assist to lost aircraft using border control radar that he tells me sees through walls. We are only a couple years out from satellite cellphone/internet service with triangulation. If you get an Iridium Satellite phone it will give you position at ground level. Other countries use their own GPS constellation and there is software that will allow existing GPS unit compatibility.
Old Mode-C Transponders are still a good back-up. Sometimes you need to climb over ten thousand feet but there’s radar coverage most everywhere.
Try your smartphone Inertial Navigation app out sometime. The one I use will be within 100 feet accurate after 30 minutes or 50 miles. Use it exploring caves to find my way back out. Still use a string and markers but the crumb trail mapping feature is cool.
Any three radio station signals (AM or FM) can be triangulated. Software can be put on your Smartphone to calculate Latitude/Longitude location. Most Smartphones have an FM receiver. The APP just needs to know where the transmitter towers are located. The radio stations transmit an embedded identifier, also most likely have a time signal embedded. Much more accurate then the old ADF or VOR/DME.
I bought an airplane with a great Northstar LORAN and loved it … until LORAN was decommissioned. It was quite as accurate or fast acting as GPS but you could sure find your way around just as well.
I got active writing to save LORAN but to no avail. That was likely >10 years ago. BIG MISTAKE to decommission it and I agree with Ben. There HAS to be a backup to GPS. If it isn’t LORAN then VOR. Even a Sporty’s handheld with VOR built in would be a backup.
Sometimes, I get the feeling that the people running our Government, the military and politicians are dumber than a box of rocks. The military — especially — is relying on fewer and fewer airframes because the force multiplying factor of GPS guided weapons allows that. Fine and dandy until it ain’t there … as Alford said above. And I’m a retired USAF flight test type.
Always been going by a saying I got from an old 1stSgt. Backups are always a unnecessary until you need one.
LORAN would make an excellent backup for GPS. A handful of LORAN stations would provide coverage for th entire USA. Not only can that relatively modest investment provide enroute and non precision approach navigation for aviation, but it can also provide navigation for ships and boats. It can also be encoded to include precision timing to assist in many critical infrastructure needs.
Carrying a backup radio makes sense in IMC. But VORs are NOT a backup to GPS. Why? Because you can fly a HDG bug to any waypoint, NAV/VOR or airport (or just use the mag compass.)
And the backup to a PFD is the MFD then the backup instruments (either round gauges or another digital set as CIrrus proves since last year.) That’s two levels of redundancy. Nothing wrong with having an EFB (Garmin Pilot, Foreflight etc) which gives a third level, then you can also add your smartphone with Avare or FlyQ on it for a fourth level…How many levels do you need anyway?
The GPS system that we all rely upon needs a backup, but it certainly isn’t ADF. ADF is arguably the least reliable and least accurate of all airborne navigation systems in use, but that is not its biggest flaw. The fact is that a small and diminishing number of aircraft are equipped to receive ADF signals. I yanked the ADF out of my plane 10 years ago as it was a waste of payload and panel space. New planes are not being built with ADF receivers and old ones are having them removed.
Loran would be a good backup but would required major re-equippage for the fleet. The best backup is what we already have: a reasonable number of VOR and ILS facilities. Nearly every airplane flying is already equipped to receive these signals, and the infrastructure is already in place. This is not to say we need to retain every VOR ground station, but a reasonable number of strategically placed VOR’s (and ILS) is the best backup choice for dealing with GPS outages.
A NDB may not be the most accurate but it is one of the MOST reliable navaids out there. KDAA has a solid state transmitter with an uptime of OVER 27 years and counting. It’s a simple system. I think that there are many pilots out there that are confused with how to fly with them due to a lack of proper training. The children of the magenta need to get back to basics. Try flying internationally, you don’t always have GPS and some times it ends up with a 1 or 2 NDB approach. An E-LORAN system would only help in the U.S. and require all new hardware to be developed. People have been complaining about dropping $3-5000 for installing ADS-B out, it would be the same or worse. I enjoyed using LORAN but unfortunately it’s time has passed.
Comment…
I found the article on backup navigation systems in general, and the the logic of decommissioning the NDB at the Cambridge Airport, in Maryland, to be of interest. As a flight instructor, I always teach my students to have a backup plan, just in case “Plan A” doesn’t work. I say to my students, always have a “Plan B, I.e., a backup plan. This logic specifically applies to each pillar of the well-known CNS triad: Communications, Navigation, and Surveillance. For example, in the context of navigation, what if GPS goes south, perhaps purposely jammed by a hostile party?
In thinking about the topic, I recall reading an old FAA AC, AC-90-92, “GUIDELINES FOR THE OPERATIONAL USE OF LORAN-C NAVIGATION SYSTEMS OUTSlDE THE U.S. NATIONAL AIRSPACE SYSTEM (NAS).” This AC was dated 2/5/1993, and it is now cancelled. Too bad, as more advanced LORAN systems, called eLORAN, could have likely served as a viable backup to GPS.
In the subject AC, on Page 18, there is an interesting section, a perspective on considering having access to a combination of three independent backup systems for navigation. The section in AC 90-92 reads as follows:
“Critical Triangle Method. Many professional pilots rely on the critical triangle method to stay out of trouble when flying over the high seas. To minimize risk, experienced pilots rely on three hdependent navigation systems (as opposed to one or even three Loran-C triads). If one system fails or provides inaccurate position data, the pilot can cross-check the navigation data with the other two units to determine which one of the three units is in error. Two independent systems alone will not work. Some examples of this concept follow:
(1) Loran-C/ VOR/VOR
(2) Loran-C/Weather radar (in map mode)/automatic direction finder (ADF)
(3) VOR/Loran-C/Omega
(4) Three separate inertial navigation system (INS) units
(5). Inertial/LORAN-C/VOR
(6) Inertial/LORAN-C/GPS
(7) LORAN-C/VFR Pilotage/VOR
(8). LORAN-C/Ground-based radar/GPS
My assessment…. The people in the public sector who made the judgement that ADF is not a viable backup system to GPS, most likely do not appreciate the notion of critical triangles of agreement. What if GPS fails, and what if the Cambridge NDB is no longer in commission, what’s left? Radar in the Cambridge area does not go to the surface. Pilotage, sure, that works, providing its VMC.. VOR navigation is also limited at low altitudes in the Cambridge area.
So, what are the options left for the GA pilot who has lost his / her GPS? I have an idea, contact ATC and request to be identified using ADS-B, then vectored to Cambridge. Wait a minute, ADS-B relies of GPS. That won’t work. So, what’s my Plan B?
The bottom line: In my opinion, saving money by decommissioning the NDB at the Cambridge Airport was not in the best interests of the GA flying community.
Just a thought, and not a sermon.