Navagating across the pond before GPS

[PhatAJ2008]

How did aircraft navigate across the vast oceans before GPS? Obviously they could not get a signal from a VOR... Just curious..
-AJ

 

[mannyaplus11]

Inertial Navigation Systems.
Before that, navigators using a sextant, loran signals, dead reckoning.
Of course, back then, plus or minus 10 miles was acceptable.

 

[Ralph Cramden]

I used dead reckoning and ADF in the DC 3 over the Caribbean back in the late 70's. At those slow speeds, low altitudes and in that area of stable wind patterns it was quite accurate if you kept your heading and ran a nav log. Used to hit Cayman Brac (no nav aids back then) dead on every time.

Google these terms: Celestial navigation, Loran, Inertial Reference System.

Over land some early nav systems were the 4 course range, light beacons and quite literally "I follow railroad".

If you want to know how the sailing ships figured it out, I highly recommend this movie: http://www.imdb.com/title/tt0192263/ Longitude. You might find it at your local library. Happy hunting in your navigation education, knowing basic skills will help you some nasty day the GPS/FMS goes Pffftt

 

[grog_sit_reserv]

Ask General Lee, Delta was really good at getting back from Europe....

 

[Bubba Dog]

Strategic Air Command KC-135 Celestial Navigation 1984. The stars and the sun with one carousel 9 way point INS that drifted at least 1 mile per hour and a Doppler that was useless on smooth seas.Primary means of navigation over the land was radar and over the pond a sextant. After crossing the Atlantic from Africa to the states Navigator was only of at the most 5 miles,usually within 3 miles.. During the day obtained a speed line with the sun. I was only the pilot. Knew I had to stay very still so to speak when taking the shots,no acceleration or deceleration and no turning for about two minutes. The navigator would give the celestial body's coordinates to the boom operator and would let the nav know when he "had the body" then shot would begin. This occurred about every 20 minutes or so. This was back before computers and GPS's. Everything including the math was done by hand. Used a slip stick to compute aircraft center of gravity. Called the navigator a "talking TACAN" but everyone knew how important they were back in those days. I really had a great respect for them and really enjoyed my days with SAC going all over the world with a great group of folks!!

 

[PhatAJ2008]

It's just amazing the knowledge and skill these navigators had back in the day. No wonder being a pilot was so prestigious and elite back then. Now all we do is basically follow a computer's instruction. Takes the skill out of being an aviator, along with the respect.

 

[Big Beer Belly]

Takes the skill out of being an aviator, along with the respect.

LOL! I'm sure today's fighter pilots would get their butts whooped by a WWI sopwith camel jock!

BBB

 

[Deli Guy]

I did it many times. Try this thread.

http://en.wikipedia.org/wiki/Celestial_navigation

 

[pilotyip]

We used to cross the pond VFR, no flight plan FL 200 to FL 290 free cruise. Big Sky theory. All radios turned off, only listen to the command net. Back then all Navy pilots flying patrol airplanes had to be qualified in Cel Nav. If we hit the coast within 20 miles it was a good flight. That is where RNP 25 came from cel nav.

 

[Donsa320]

In the 1950's before inertial we had the old LORAN which was terrible usually because it was broadcast at about 1650khz so there were a lot of skywaves and the ground wave did not go very far. One had to pick a delay line to get a LOP and hope it was the line you wanted when you charted it. A 50 mile triangle would be a pretty good fix. To back it up we had celestial, if there was no cloud cover above us and, as we were not pressurized, there usually were clouds. In the daytime we also had a driftmeter and a crude radio altimeter which would allow us to measure drift if there were white caps or distinct waves over water or land formations if over land. The radio altimeter would give us our actual altitude and by timing a speck of wave or whatever as it passed through the driftmeter viewer we could compute a groundspeed as well as see the drift angle. Best to have LOTS of fuel.

DC

 

[ATRCAPT]

Read "Fate is the Hunter".

 

[328dude]

You can still do it without UHF as well. Did it last year.

 

[johnnyb]

one carousel 9 way point INS that drifted at least 1 mile per hour

Man I was dragging a 747 classic across with one of these just 3 years ago ( and our tolerances were 3 miles drift per hour).

 

[Pat Fabin]

Don't forget OMEGA/VLF!

 

[AA717driver]

Now all we do is basically follow a computer's instruction. Takes the skill out of being an aviator, along with the respect.

You STILL have to be able to fly an airplane. If you want to be a button-pusher, you can. You'll be worthless as tits on a boar but you'll still get to brag that you're a "pilot" in the bar.

Automation is a tool. You control it. Don't let it control you. Even A320's can be hand flown...TC

 

[freightdogfred]

Don't forget OMEGA/VLF!

Ahhh..yes, I was wondering when somebody would bring that up. Many crossings with those old Tracor 7800's, MNPS certified +or-5 miles, 95 % of the time. (provided there was no solar activity.) More than once at about 30 west one would start heading north, and the other south-Split the difference and start dead reckoning. Compass heading, drift angle, airspeed and time, just like old Lucky Lindy.

 

[Phaedrus]

Speaking of sextants and LOPs...that reminds me of breaking up the boredom by popping hard boiled eggs out the top of the sextant port trying for a direct hit on the vertical fin of the 130.

 

[tomgoodman]

Where am I?

And there was "Ocean Station November", a ship anchored about halfway to Hawaii, which could give you a radar fix from his (approximately) known position. I think there was an "Ocean Station Papa" in the mid-Atlantic as well.
A truly ancient radio navaid was "Consolan", sort of a super, over-the-horizon ADF. One old navigator said it would tell you which half of the world you were in.

 

[Donsa320]

And there was "Ocean Station November", a ship anchored about halfway to Hawaii, which could give you a radar fix from his (approximately) known position. I think there was an "Ocean Station Papa" in the mid-Atlantic as well.
A truly ancient radio navaid was "Consolan", sort of a super, over-the-horizon ADF. One old navigator said it would tell you which half of the world you were in.

Ah yes Consolan. We tried it a few times in Europe. Not worth much. But we could tune in the teletype stations on Iceland on our ADF receivers while we were still on the ground at Prestwick. They were very powerful, but no ident.
I believe the ocean station ships did not really anchor. They were to stay in a rather large area and they did it by steaming into the wind and current to the edge of their area and then drifting back across it to the other side. As I recall they transmitted some coded info on their NDB signal which let you calculate roughly where within their area they really were.

DC

 

[Donsa320]

Read "Fate is the Hunter".

Yep and in the movie "The High and the Mighty" the radio altimeter they use is the one I referred to for use with the driftmeter. That is why it was at the navigators station, not in the panel. Gann got most things right. In "Fate..." Gann also makes remarks about chasing seniority numbers in hopes of beating them. Usually futile!.

DC

 

[pilotyip]

How Rad Alt was used for Nav

The radar alt was used for pressure pattern Nav; you flew a constant altimeter setting to navigate south of a high-pressure center in the Northern Hemisphere eastbound, or north if westbound. That way you kept the tailwind all the time, and you moved left or right at a constant radar alt height to keep the altimeters matched to the pressure altimeter. I never used it, but I had to demonstrate how to use it on my Nav school final exam. Was told it was used in 40-50's in recips like C-54, C-118, and C-121.

 

[seagle]

Grid Navigation

And let's not forget about grid navigation for those trips across the pole to Moscow. Ground Plot DR, Air Plot DR, Wind Computations, MPP, Compass Precession and Precession and Nutation of the celestial bodies.

Wow - this is bringing back some memories.

 

[Spooky 2]

Ah yes Consolan. We tried it a few times in Europe. Not worth much. But we could tune in the teletype stations on Iceland on our ADF receivers while we were still on the ground at Prestwick. They were very powerful, but no ident.
I believe the ocean station ships did not really anchor. They were to stay in a rather large area and they did it by steaming into the wind and current to the edge of their area and then drifting back across it to the other side. As I recall they transmitted some coded info on their NDB signal which let you calculate roughly where within their area they really were.

DC

The ship would stay within a 100 mile grid and report which grid he "thought" he was in, thus giving you a chance to do a reverse plot on your position based upon his aasumed positin within the grid. All very crude by todays standards. Besides the ship in the NA there was a Candaian ship (Yankee) up in the NoPac that worked those waters in the same manner. Lets see a show of hands on how many board members have a Flight Navigators ticket? Pan Am 1966/67 thank you!

 

[seagle]

Flight Navigator Ticket

I'm in.

 

[Spooky 2]

And let's not forget about grid navigation for those trips across the pole to Moscow. Ground Plot DR, Air Plot DR, Wind Computations, MPP, Compass Precession and Precession and Nutation of the celestial bodies.

Wow - this is bringing back some memories.

"accross the pole"? Can't imagine any tracks or routings that would actualy take you accross the N Pole unless you had deviated intentionally to cross over or near the pole. My experience with Grid was limited to European to west coast of the USA where you would pass through the NCA/AMU at or around 73N.

 

[loewinbrau]

At ATA, we still fly all over the world using the Litton 92 INS. Just flew trans-pacific in an L1011, SEA-OKO yesterday. The 92 is quite accurate, but not very user friendly.

 

[bocefus]

And there was "Ocean Station November", a ship anchored about halfway to Hawaii, which could give you a radar fix from his (approximately) known position. I think there was an "Ocean Station Papa" in the mid-Atlantic as well.
A truly ancient radio navaid was "Consolan", sort of a super, over-the-horizon ADF. One old navigator said it would tell you which half of the world you were in.

Don't ever recall Ocean Station Papa in the Atlantic but Ocean Stations Charlie and Juliet were in the Atlantic with NDB's for obtaining a fix. Never heard of them providing radar fixes??

 

[seagle]

Grid Navigation

Spooky 2,

I think we may be talking about two different grids. When I was in SAC we used grid charts to help navigate up north because of the rapid convergence of longitude lines, thus affecting MH and TH rather quickly. Grid navigation eliminated the need for the compass to be "slaved" and allowed navigation in the DG mode. Hope this is right - I'm going back 25 years.

 

[Crzipilot]

Seagle, think your right. Was qualified Grid, but never did it, and barely remember it. But we had route authority using DC8's with omega 7800/7900's but with routes going north, had to switch to Grid, I.E. plotting charts were square grids and you navigated in DG, taking plots etc....

 

[seagle]

Grid Navigation

Crzipilot,

I remember the toughest part of Grid navigation was Grid entry and Grid exit. If you miscalculated Grid entry you were going to have a long day. Once you were in Grid, all you had to do was kill the drift and calculate compass precession to maintain your Grid track.

I recently flew a King Air 200 with the Collins Pro Line 21 - we have truly come along way from the days of radar and celestial navigation.