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Fundamental Navigation Question

David Paule

Well Known Member
Right now I know of these basic navigation systems. Are there any I'm missing?

GPS,
VOR,
Pilotage,
Dead Reckoning.

I understand that Loran is now decommissioned and unavailable; and for our small airplane purposes, I expect that inertial navigation and celestial navigation are impractical, so I didn't include those.

Thanks,
Dave
 
ADF
DME
Marker beacon
Localizer/ILS (technically a different system from VOR)
MLS or INS if you're so equipped
GLONASS if you want to be pedantic (not the same as GPS)

And how about ground-based RNAV... if you can find a working KNS 80...
 
I'm not currently flying any GA. Are NDB's still in service? I'd add it to your list. Before GPS there were navigation units that uses two DME with a VOR signal for a LAT/LONG solution. King KNS-660 and KNS-80 are two.

The Inertial Navigation System (aka INS) is a valid type of navigation system in wide use today. The triple seven, 767, MD-11 all have three on board and used as a backup and a crosscheck against the GPS and grades its own confidence and integrity of its position solution. So if the GPS starts to drift off it can be turned off and we rely on INS then. INS is self contained using gyros and accelerometers. It knows it position when it begins a flight, and will have some drift in its solution over time.

BTW, the GPS signal is easy to jam. Its a very weak signal....not much power to it. The enemy has also learned how to spoof it....meaning the GPS thinks its location is not where it is, so an aircraft might get "off course" but think its on course. Those who fly worldwide know about this. Reports of this taking place are around Ukraine, Iraq, Iran, Syria, etc. Maybe Turkey. Tip of the Arabian Peninsula where drones use this cheap accurate system to guide it to a target.
 
You must be thinking of something other than a KNS-80. The KNS-80 did RNAV via a "phantom VOR," using VOR and single DME to allow the pilot to navigate to the phantom VOR as if a real VOR was at the phantom's location. LAT/LON was not involved.

And while GPS signals are indeed low power, they are spread spectrum and gain a certain amount of jam resistance that way. It's been too long since I studied all that, sorry...
 
One other system for your list is DME/DME. It's a time-difference-of-arrival RNAV system that pings multiple DMEs from a database to build a nav position. You'll see it on transport-category airplanes but as far as I know it hasn't migrated down to GA.

A side note - inertial nav isn't practical now for the SWaP we have available in our small airplanes, but as the sensors that drive our glass-cockpit AHRS or ADAHRS are improved, a GA IRU isn't so far-fetched.

ds
 
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I think we're all showing our age. Does no one practice celestial navigation anymore? Easier in a tip-up than a slider. Uselsss in IMC though, so you need at least one of the above systems.
 
A flesh and blood navigator! The C130E had a nav station where the Nav did Celestial nav using a bubble sextant to do star shots. There was also an analog track/distance counter that used doppler radar to convert ground speed and drift into a navigation solution. We managed to find every bar we went looking for so it must have worked!
 
A flesh and blood navigator! The C130E had a nav station where the Nav did Celestial nav using a bubble sextant to do star shots. There was also an analog track/distance counter that used doppler radar to convert ground speed and drift into a navigation solution. We managed to find every bar we went looking for so it must have worked!
I spent 4 years as a C-130 Navigator. Did all the above, plus Omega and Pressure Pattern navigation. And of course radar ground mapping, pilotage and dead reckoning.

Who remembers pressure pattern lines of position?
 
I was asking as a day VFR pilot flying a Cessna 180 and building an RV-3B. While some methods are fascinating (INS for example) they aren't practical here. I'd forgotten ADF.

In any event, please continue. I merely wanted to interject the basis for asking; and I don't want to arbitrarily truncate the conversation.

Dave
 
Who remembers pressure pattern lines of position?

I do! Saved my bacon on my first ocean crossing as an aircraft commander when both aircraft compass systems went Tango Uniform. I was fortunate enough to have a brand new 2nd Lieutenant navigator fresh out of school who was an honor graduate and extremely cool under pressure. He quickly converted to grid navigation using pressure pattern and we hit coast-in within 15 NM of our desired track. I bought the beer!

My question, does tacan still exist? It’s different from VOR/DME. Definitely showing my age!
 
A flesh and blood navigator! The C130E had a nav station where the Nav did Celestial nav using a bubble sextant to do star shots. There was also an analog track/distance counter that used doppler radar to convert ground speed and drift into a navigation solution. We managed to find every bar we went looking for so it must have worked!
I shot the sextant too many times.
Favorite saying was

LAND HO

Always made the nav 😀

We were always Lead, go figure



Boomer
 
And some items from the past:
LORAN A - Derived from "G" in WWII bombers
LORAN C - A better ground based system
OMEGA - a worldwide ground system used into the 1980s
Transit - Satellite navigation well before GPS

Jim C
 
Bon fires, 4 course range, ADF airways in Alaska
IMG_0271.png
 
When I first saw this post I thought that the op was just discussing modern day nav for small airplanes, but since this has now branched out to include everything under the sun, I'll add my personal favorite, seen below.
 

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The concrete arrows are cool; some are still laying around, I believe. How about painted barn roofs?
Boy THOSE were the days! Airway beacons were gone by the time I started except on some mountain passes but concrete arrows, barn roofs with shingles making arrows, runways or airport buildings with the names spelled out (still see those!). I get misty when I pull out some of my old sectionals with the ubiquitous red line and the little tick marks along the line to mark distances to navigational landmarks along the route. The note pad on my knee board with those landmarks listed to calculate times and figure out ground speed. I still have the round slide rule (really? Yes, really!) I used in the Cub to calculate ground speed; used like the round calculator part of an E6B. Other than student training, are those still used? I was in high cotton when I got my Garmin 90 GPS! I still would use the maps with the line on them..... I feel fortunate to have been brought up on a lot of the 'old stuff' before all this new-fangled navigation things came into use! One had to actually LOOK OUT THE WINDOWS! :)
 
When I first saw this post I thought that the op was just discussing modern day nav for small airplanes, but since this has now branched out to include everything under the sun....
I was, but the discussion is interesting. Haven't been able to glean much useful from it, though yet, but there sure are many ways people managed to navigate. Polynesians using wave patterns could, with imaging and machine intelligence, possibly be adapted today, bet it won't be though.

Dave
 
Low frequency range was the primary nav and also instrument approach prior to WWII. I think Charleston WV was the last range facility in the lower 48. Bob Bucks final book-North Star Over My Shoulder is a fantastic read. From primary glider to Boeing 747 and a lot of airplanes in between.
 
Was the "range" system the one where you had a "dit" "daw" on both sides of a "line" going to the airport and If you could hear
a "Daw" "daw" "daw" in the headphones, you were on course for the airport runway, like a localizer needle . My brother, who was
twenty years older than me, had to shoot one of those for his instrument checkride. I think ILS took it's place, which is very old also.
I do remember as a kid we flew "on instruments" with a Superhomer and a 27 channel comm. Yes, the traffic was light!!
 
Was the "range" system the one where you had a "dit" "daw" on both sides of a "line" going to the airport and If you could hear
a "Daw" "daw" "daw" in the headphones, you were on course for the airport runway, like a localizer needle . My brother, who was
twenty years older than me, had to shoot one of those for his instrument checkride. I think ILS took it's place, which is very old also.
I do remember as a kid we flew "on instruments" with a Superhomer and a 27 channel comm. Yes, the traffic was light!!
The range was enroute and in many cases used for approaches. In some cases it lined up with a runway but not always. In central NY in some cases the range "legs" lined up with the older airways beacon system. I have a collection of sectional charts that date to the 30's that show the ranges and later the VOR's as well as the beacon system.
The first radio I ever used was a Superhomer. You have mixed up two Narco radios. The one used for IFR was the Omnigator. The Superhomer was VFR only.
Just after I got my instrument rating I was flying a Beech 18 and a Aero Commander 560. Both had tuneable nav and com, no transponder, DME or autopilot.
 
I spent 4 years as a C-130 Navigator. Did all the above, plus Omega and Pressure Pattern navigation. And of course radar ground mapping, pilotage and dead reckoning.

Who remembers pressure pattern lines of position?
We were coasting out from Goose Bay in a life far, far away and the Loran and our dopplar in my C130B tanked. My full Colonel nav said, not to worry son, I’ll use pressure patterns and sun shots. Me, being a new 1st Lt. AC said sounds good. Several hours later we coasted in over Southern Ireland about 4 miles off our planned point of landfall. Those old guys were good with their sextants and magic.
 
Navaid blast from the past, before doppler and the Inertial/GPS thingies:
If you are doing dead reckoning and know your drift angle and thus your track , you are most of the way to knowing everything you need to know to get there.
The APS-42 airborne radar and others had a drift angle/track mode. If you are in the middle of the Pacific, say, you could use this feature to find your track by using the blue phosphor scope filter and manual antenna steering. The radar return line painting the water has a scintillation which will change when the antenna direction is aligned on the aircraft track. Just read out the magnetic track on the bezel. Presto, there's Kwajalein! "When we lost the R7V's long wire(loran,HF), I thought we were in trouble". (1957)
 
In the Herc we had Omega, Doppler, and celestial as primary means of long range nav.
On one particular long winter trip, flying into the wind from England to Halifax, we lost both those systems after coasting out and the sextant port iced over. We had a sub 200kt ground speed for most of the crossing, so I think it was about 11 hours total, with probably 8 hours without any reliable nav. We used dead reckoning primarily and were able to cross reference commercial radio stations off Iceland and Greenland with our old and very sensitive coffee grinder ADF. We were pretty close to the flight plan centerline coasting in.
We also had Omega in our some of our TWA 727's that we used for over water nav to Puerto Rico. Otherwise those were only equipped with two VOR/ILS receivers and an ADF.
We flew MLS ( Microwave) approaches at Horizon Air in the DHC-8. That was a really good system with a steady beam and glide slopes up to 5.0 degrees.
Has anyone mentioned Fan markers yet?
There used to be one west of Portland near Kelso - the Columbia fan marker.
When my dad was a PDX tower controller in the early 60's, they had inbound aircraft report the Columbia fan marker. That marker was still operational into the 90's if I remember correctly.
 
At Delta we had Omega navigation in our DC-8’s almost 50 years ago. Omega is a VLF system (very low frequency), and was the first navigation system providing true global navigation coverage. When they put that in our -8’s, I thought we had suddenly jumped forward into the 20th century. The only other nav systems we had was 2 navcoms and an ADF - and it was a CAT II ship…..
 
Not exactly navigating, but I always know when I get home. This is the Beechcraft factory in Wichita.
 

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I think we're all showing our age. Does no one practice celestial navigation anymore? Easier in a tip-up than a slider. Uselsss in IMC though, so you need at least one of the above systems.
I do but not in my airplane. I have a really nice sextant for sale actually.

Also, OP is missing "IFR" - I Follow Roads - Rand McNally for charts
 
Has anyone mentioned Fan markers yet?
There used to be one west of Portland near Kelso - the Columbia fan marker.
When my dad was a PDX tower controller in the early 60's, they had inbound aircraft report the Columbia fan marker. That marker was still operational into the 90's if I remember correctly.

Okay, I was following along, nodding that I had at least heard of all these navigation systems. But fan markers is a new one for me. What is a fan marker and how does/did one use it?
 
Okay, I was following along, nodding that I had at least heard of all these navigation systems. But fan markers is a new one for me. What is a fan marker and how does/did one use it?
They were basically high powered marker beacons with a wider area of reception than a standard outer marker. A standard marker beacon receiver would give an aural and visual alert as you flew over it. I did a little googling and apparently it's been removed from the AIM now.
The only one I have experience with is the Columbia fan marker that used to be to the west of Portland, Oregon, on the Columbia River near Kelso, Wa.I believe It was depicted on the sectional chart if you can find an old one. I think that one was decommissioned in the late 80's or early 90's.
 
Best thing about having ADF was you could listen to AM radio before Sirius XM Came on the scene. In a Cessna spam can you had a decent length of time before finding a new station.
 
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I'm not currently flying any GA. Are NDB's still in service? I'd add it to your list. Before GPS there were navigation units that uses two DME with a VOR signal for a LAT/LONG solution. King KNS-660 and KNS-80 are two.

The Inertial Navigation System (aka INS) is a valid type of navigation system in wide use today. The triple seven, 767, MD-11 all have three on board and used as a backup and a crosscheck against the GPS and grades its own confidence and integrity of its position solution. So if the GPS starts to drift off it can be turned off and we rely on INS then. INS is self contained using gyros and accelerometers. It knows it position when it begins a flight, and will have some drift in its solution over time.

BTW, the GPS signal is easy to jam. Its a very weak signal....not much power to it. The enemy has also learned how to spoof it....meaning the GPS thinks its location is not where it is, so an aircraft might get "off course" but think its on course. Those who fly worldwide know about this. Reports of this taking place are around Ukraine, Iraq, Iran, Syria, etc. Maybe Turkey. Tip of the Arabian Peninsula where drones use this cheap accurate system to guide it to a target.
Hello Brooks!

Bill
 
Right now I know of these basic navigation systems. Are there any I'm missing?

GPS,
VOR,
Pilotage,
Dead Reckoning.

I understand that Loran is now decommissioned and unavailable; and for our small airplane purposes, I expect that inertial navigation and celestial navigation are impractical, so I didn't include those.

Thanks,
Dave

The reality right now, there is GPS, VOR/DME, and ILS. GPS or VOR enroute. For approaches at smaller airports, GPS typically or occasionally an ILS, and the fewer VOR approaches still left often require DME (that you are probably using GPS for anyway). Almost none of the small airplanes I've flown have ever had DME. WAAS GPS and a VOR/LOC, plus ATC radar is sufficient 99.999% of the time. That's what my airplane has. My GPS, VOR, and COM radio are all separate units, which is enough redundancy for me.

Anyway, RADAR is the biggest one I see missing in this thread so far. Radar vectors are the most common nav system in the terminal environment, and that depends on a DG, compass, and a COM radio.
 
Or you can do the WATER TOWER fly by.
That will also help.

Boomer
This. I would just fly until I saw a water tower, fly over to it and read the name of the town off of it. Make your course adjustment and go back to dead reckoning.
 
My PhD thesis was on Omega navigation for GA, and yes, that was a long time ago. Even did an Omega approach in VMC, data volley from a precision ground radar, IIRC.
 
Ahhh back in the day on transoceanic flights as an enlisted nav on USMC KC130s. Accurate positions could be determined, at night, using a periscopic sextant and 3 selected star shots (unless in clouds). Took several minutes (10-15) to shoot and plot them. Turbulence would widen the triangle & degrade accuracy. During daylight - sun, moon & planets would give lines of position (again weather permitting). Crossing them with Pressure Line and/or dead reckoning would give a decent position. ADF was nice to listen to radio stations. Amazingly, always got to where we were going.
 
Right now I know of these basic navigation systems. Are there any I'm missing?

GPS,
VOR,
Pilotage,
Dead Reckoning.

I understand that Loran is now decommissioned and unavailable; and for our small airplane purposes, I expect that inertial navigation and celestial navigation are impractical, so I didn't include those.

Thanks,
Dave
I know it's decommissioned, but I'm willing to bet I'm the only one here who has actually used a four-course (a/n) range. I also had a question about it on my private written.

Jerre
 
I know it's decommissioned, but I'm willing to bet I'm the only one here who has actually used a four-course (a/n) range. I also had a question about it on my private written.

Jerre
I have known several pilots who will admit that they have landed at an airport and gone into the FBO to see where the pin is in the map.
 
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