Sextant in airplane
8 min read

Flying in my little single-engine Cessna, my yoke mounted GPS unit gives me my exact position anywhere on the face of the earth, as well as a host of other valuable information and is a marvel of modern technology. It wasn’t always so. I was a crewman on a Navy land-based long-range patrol plane (P2V Neptune) back in the early 1960s and I’ll tell you all what it was like.

All of my flying was done in the Pacific between the West Coast of the US and the Far East. We hit just about every island in between including Hawaii, our home port, Midway, Wake, Guam, the Philippines, Japan, Taipei, Okinawa, Vietnam, the Aleutians, and many other smaller islands which are just dots on a chart.

P2V flying

Navigating all the way across the Pacific in a P2V – no GPS to depend on.

The Lockheed P2V was a twin-engine (actually it had two small jet engines added in later models to increase takeoff performance) mid-wing aircraft with a crew of 10. Two pilots, navigator, tactical coordinator, flight engineer, radio operator (me), radar operator, two sensor operators, and an observer/mad operator. Neptunes were unpressurized so we normally stayed below 10,000′ to avoid wearing oxygen masks. Our absolute service ceiling was about 30,000′. Long-range cruise speed was 180-200 kts, so a trip from San Francisco to Hawaii was 10 to 12 hours depending on winds aloft. I made that crossing seven times.

All crewman wore flight suits, survival vests, mae wests, parachute harnesses, and headsets plugged into the intercom system. In Arctic climes we had to wear waterproof rubber POOPY suits with watertight hand, leg and neck cuffs. Those were like being enclosed in a plastic baggy and we would lose a few pounds from perspiration after a long flight.

Our old P2Vs were noisy, drafty, and smelled of oil, gasoline fumes (on long flights we carried two reinforced rubber gasoline bladders hung in the bomb bay, and they leaked like hell), exhaust fumes, electrics, etc. But it was perfume to me.

The front and rear of the plane were separated by the main wing beam with a tunnel provided for passage. My position in the radio compartment was just aft of the wing beam.

I have many memories of exciting and terrifying times on the P2V but in this missive I want to talk about navigation. How did we find our way across the vast Pacific in those primitive days?

E6B slide rule

With a slide rule and a map, Navy airplanes flew all over the world.

Our primary nav method was “Dead Reckoning” (emphasis on “dead”). During preflight briefing we would gather what little weather info was available in those days before satellites. The weather folks would give us their best guesstimates of the winds based on reports from ships at sea and other aircraft and we would plot an initial heading.

After launching (Navy lingo for takeoff) we’d fly that heading and plot an assumed course and use any land-based navaids that were still in range for a cross check. About 150 miles out to sea we would lose the land-based signal and would then rely on the navigator’s “How-Goes-It,” a running log of our position, fuel burn, ETA and “point of no return.” (“Forget it, guys. We ain’t got enough gas to make it back.”)

One of the primitive tools we used was called a driftsight. It was sort of a inverted periscope extending from the belly of the aircraft. Laying flat on the deck, one could look through the driftsight at the waves below, assuming we were below the clouds. We lined up two parallel cross hairs in the eyepiece with the movement of the waves, and then could measure our crab angle, or the difference between the aircraft heading and its actual track. Knowing our true airspeed, we could then compute the winds using simple geometry. At night or in clouds, that was impossible, of course, and most of our flights seemed to be at night.

We also used LORAN. These stations, manned by the Coast Guard, were scattered all over the Pacific and were the first real high tech tool available to us back then. I’ll do my best to explain how LORAN works, briefly. Suppose you’re standing on the beach at Waikiki with a LORAN receiver. Two stations, one on Guam, the other at San Diego, transmit a signal towards you at the exact same instant. The signal from San Diego will arrive first, followed milliseconds later by the signal from Guam.

The LORAN receiver measures the time interval and knowing that, we could compute a line of position. Now, you do the same thing with two other stations and get another line of position. If the LORAN operator is careful and the atmospheric conditions are acceptable, the two lines of position should intersect on the beach at Waikiki, or within a few miles. The trouble with LORAN was that the signals were in the HF band and very susceptible to interference from electrical storms and static. Often, when we needed it most the signals were unreadable.

Sextant in airplane

Doing it the old fashioned way – with a sextant.

When we were in clear weather or above the clouds, hardly ever it seemed, we used my favorite, the sextant. I bugged the navigator to teach me celestial navigation and after a while he would let me take the star shots. I stood on a stool near the nav station and looking through the sextant eyepiece would try to keep the chosen star in the middle of two crosshairs and a bubble which were both jumping all over.

The “bubble sextant” was devised for unstable aircraft and included an averager to even out the wiggles. You tried to keep the star, crosshairs, and bubble centered for two minutes, some mean feat in turbulence. A sextant measures the altitude (inclination) of a star, or its angle above the horizon, and its azimuth, or angular distance from true north. The bubble represented our horizon, like a level. Now, if you shot the right star, you had its angle above the horizon and noting the exact time of the sighting, you’d look in the almanac for a line of position. Quickly then, you’d pick another star about 90 degrees from the first and shoot it the same way, now having two lines of position that, like LORAN, should intersect at your “fix.”

We’d tune in to a continuous radio broadcast from the Naval Observatory to get a “time tick” as watches in those days were not accurate enough. Big errors were common due to things like shooting the wrong star (on a coal black night over the Pacific there are millions and millions of them), sloppy aiming, or reading the incorrect angle, or data in the Almanac. But if you were careful, you’d come close and it was really satisfying to now feel like you knew where you were.

Just a note here to say I’m impressed to this day with the professionalism and competence of those guys I flew with. We all were masters of our craft and depended on each other with our lives. Our aircrew was a tight knit unit and every man strived to do his best. On many an occasion that got us through a bad situation without a scratch.

Midway to Japan map

Midway Island to Japan, an awfully long flight to do via dead reckoning.

Often, we’d be flying in terrible weather for hours, unable to get either a LORAN fix or a star shot. We’d then truly rely on dead reckoning using just our magnetic heading and airspeed to compute a position. If fuel was ample, we’d sometimes attempt to climb above the clouds for a star shot, but not knowing the cloud tops, we often could not risk burning the extra gas to climb.

On one occasion, flying from Midway Island to Japan, (about 2400 miles), we were totally lost, not having been able to get a fix for hours. Our P2v’s max range was just a little bit more than 2400 miles and we all figured we’d have to ditch if we were off course by very much. If you look on a globe you’ll see that there is no place to divert along that route, just vast, empty ocean. The navigator kept giving the pilot headings to fly, using God only knows what instinct, and after what seemed like an eternity we were able to tune in a radio station in Yokohama and get a bearing. Turns out we were less than 50 miles off course and were able to get to Iwakuni Naval Air Station with gas still in the tanks. Nice job, Harry, wherever you are!

Modern navigation to me is incredible. I look at my small GPS unit and am awestruck by its capabilities and think back to those days when we hardly had a clue. It was teamwork and perseverance we relied on then. Today, if you use a moving map display you know exactly where you are within a few feet. Now that’s amazing!

John Dill
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39 replies
  1. Mark Fay
    Mark Fay says:

    Hi Mr. Dill:

    Thank you for this story – I really enjoyed it.

    I often think about how fortunate I am to not have to compute my desired track or current course. For people thinking about travel by personal aircraft, if you can use an automobile navigation system, you can learn an aviation class GPS. The certainty and safety it provides makes navigating child’s play compared to what you had to do in the remarkable P2v. Now if I just had those jet boosters on my Cessna! ;)

    GPS is one of many reasons why if you want to learn to fly and carry yourself around the country there is no better, safer or more capable time than 2014!

    Thanks again.

  2. Duane
    Duane says:

    John – very interesting flashback. You bring home the essential urgency of knowing where the airplane is, an urgency not felt to that degree in any other mode of transportation, either ground or sea: the ultimate limitation of fuel on board, such that when it’s gone, the trip terminates in a very dangerous manner. At least you had a large crew and one person designated as navigator; in single pilot personal aviation, it’s a much harder challenge.

    There’s a certain contingent of old timer pilots and purists who constantly bemoan the availability of cockpit electronics and automation, their theory being that pilots no longer fly the aircraft but just are going along for the ride in the cockpit, not paying attention to much of anything. And that as a result, these folks assert that flying is getting less safe.

    Of course, the accident stats say otherwise – the fatal accident rate in GA is far below what it was a couple generations ago.

    Sure, it is always possible that a given pilot will act negligently in the cockpit, and as a result survive a little longer with cockpit electronics and automation than he/she would have in the old days, but still be a danger to all. But all things considered, the now-ubiquitous GPS directing an autopilot frees up a single pilot so that he/she can actually afford to look around outside the aircraft (for traffic, weather, obstacles, etc.) and better manage the flight. There’s significant value to not being distracted by panic-inducing “where the heck am I?” thoughts. A distracted or panicked pilot is far more likely to neglect to fly the plane, or fail to keep it clean side up.

    We’ve come a very long way. The better our gear the more we are able to focus on safe and fun flying and not focus entirely on managing the mechanicals or constantly validating the flight plan. The fewer mental tasks we have to bear in the cockpit, the better we can perform the remaining essential tasks of aviating.

  3. Charles Lloyd
    Charles Lloyd says:

    In the 50s during our junior year of NROTC we spent the whole year learning celestial navigation. It was a big deal on your summer cruise between junior and senior years to practice shooting stars and plotting positions just before dawn.

    Now the Naval Academy and NROTC have dropped celestial navigation. It is no longer needed.

    Aircraft GPS is the biggest advance in navigation since VORs replaced Radio Ranges.

    • Doyle Frost
      Doyle Frost says:

      Charles, I see a big potential problem here, and it deals with the mind set of our leaders, world wide. Technology is great, but, as a former avionics tech, USAF and USN, I remember the times the “latest and greatest navigation equipment” failed. This included some rather fancy navigation equipment, (before GPS, but based on Doppler radar and celestial nav. equipment.)
      Without a good grounding in the fundamentals, and continuous refresher practice or training, there is too much chance for problems to become a “final event.”

    • John Gaither
      John Gaither says:

      I too remember Celestial in the late ‘60s, particularly my “day’s work in navigation” that I had to do over Christmas “break.” I have heard that they are again teaching celestial to Midshipmen — right thing to do.

    • Waltet Nowosad
      Waltet Nowosad says:

      I flew in P-2s in the late 50’s. this brought back some memories. Before my squadron returned from deployment, I was on loan to the flight following center at Barber’s Point. I tracked transPac flights and learned to use the E-6B. Lot of responsibilities for a young E-3.

  4. Ron Barrett, USAF Ret Nav
    Ron Barrett, USAF Ret Nav says:

    John,
    Interesting picture of a 1965 USAF Navigator taking a celestial shot, in a C-124C aircraft using the D-1 “bubble” artificial horizon sextant. The C-124C was that of the 7th Logistic Support Squadron (Special) a PNM unit. PNM=Primary Nuclear Mission. The 7th was a “Log” squadron that interfaced between the AEC, now DOE, and the US military strategic nuclear stockpiles and weapons delivery (SAC) units. Lt. Ron Barrett had at that time 3,000 hours of nav time. In the 60’s it was easy to fly 100 hours a month or more in the C-124.

    This picture is posted on http://www.usaf-nav-history.com & free use by http://www.afnoa.org
    AFNOA= Air Force Navigators Observers Association. Fun flying, Ron Barrett, USAF Ret Nav

  5. Captain W. C. Courtney, USN (Ret)
    Captain W. C. Courtney, USN (Ret) says:

    Thanks for the article. I flew the P2V-5F over the Atlantic Ocean and Mediterranean Sea in the early 1960’s. As a new squadron pilot I started as a navigator and remember well the APN-4 loran and the bubble sextant. I flew a mission out of the Azores during the Cuban Missile Crisis, as copilot. On the flight the navigator couldn’t get a fix for 8 hours. We were below the clouds at night and there was no loran coverage. It was all dead reckoning; dead reckoning with numerous course changes while searching for a submarine. En route back to the Azores we tuned in an ADF station. Luckily we finally locked onto the airport TACAN station. The airport was 10 degrees behind the port wing at 120 NM. The ADF bearing was going to take us to Africa. That was a real problem since we were low on fuel. We believe that the ADF signal was a deceptive one coming from a Soviet trawler. The navigator was only 15- 20 NM off after all the maneuvering. On these Cuban Missile Crisis missions we carried a full war load of weapons. We were searching for a Soviet submarine en route to Cuba. On the above mission we found the sub just before having to leave station. It was a diesel powered sub and he was snorkeling. He dove but our relief found the sub surfaced, refueling from a tanker, after dawn. Navigation sure has changed.

    • Captain W. C. Courtney, USN (Ret)
      Captain W. C. Courtney, USN (Ret) says:

      I need to add that I now fly a Garmin G-1000 equipped C-182T. You put the flight plan into the system and the autopilot will precisely fly it, including the instrument approach at the destination. That is a long way from the P2V’s, or even the P3C’s, I flew.

  6. gerald gaston
    gerald gaston says:

    boy does this bring back memories. i was with VP2 and VP7 and can recall lots of time not knowing where we were at. Only the sextant and the APS 20 radar were reliable and saved the day.

  7. Bernie Sidley
    Bernie Sidley says:

    Thanks for a great article. I too was a crew member on a P2V-7 in VP-56 during the early 60’s. This brought back a lot of (fond) memories. It’s amazing to me how we did all that we did, and how far technology has brought us.

  8. Warrren Smith
    Warrren Smith says:

    I am always reminded of the old story about the B17 bomber starting out on its mission right after take off. The pilot called the new navigator’s attention to his .45 auto’ lying on the glare shield. The navigator asked what that was all about.
    “I will shoot you if you get us lost, dammit.”
    With that, the navigator laid his .45 on the chart table.
    The pilot asked what that was for and the navigator said..,
    “I will be the first to know we’re lost.”

  9. Ken Schwendeman
    Ken Schwendeman says:

    My Dad, Joseph R. Schwendeman, CAPT, USNR, flew P2V Neptune variants for about 20 years, finishing as a Reserve Squadron Commander out of Andrews AFB. His first 11 years were active duty, and he flew out of all of the Atlantic bases, such as Iceland, the Azores, and Rota Spain between 1952 and 1974. He taught me how to fly, and started the Bachelor Degree Flight program at Eastern Kentucky University. I was born in the Pensacola Navy Base hospital while he was assigned there instructing multi-engine and navigation. He passed last October, and I miss him greatly. He told many stories similar to the one related in this article. He loved flying and the Navy, flying up to the very end.

    • Mike Thompson AX2
      Mike Thompson AX2 says:

      I flew as 1st tech for over 1 yr. with a mustang Capt. C. Wyman. I still have some of the used flight maps of the North Atlantic. Fond memories Glad you had such a time with your Dad.. I flew in P2V -7 148350.. Interesting times during that era..

  10. Joel Godston
    Joel Godston says:

    Oh yea, I remember so well taking those sexton moon,star, water, and land ‘shots’ for our B-47 Bomb/Navigator; flying from Little Rock AFB to Fairford, England, and Moran Air Base in Spain…back in 1956-57….those were the good ol’days. Our Aircraft Commander flew B-17’s in WWII from the same Air Base in England…..same quonset huts and ‘potbelly’ stoves he had in 1944-45 when he was there

  11. john dale
    john dale says:

    i started flying with my dad-and there were still some adcock ranges-still have the sectional charts for them—all low frequency–and try to identify which sector you were in. when i did learn how to fly i much appreciated the ease of a vor, but really kept an eye out the window with pilotage and confirmed with dead reckoning. you never knew if your electronics would go out–and besides, it was nice looking out the window every now and then.

  12. Tom McIntyre
    Tom McIntyre says:

    Great story and well told.

    I was attached to VP-6, flying P2V-5 and enjoying hanging on that sextant, serving the required time as a Nav before a pilot seat opened up. Great training for a 52 year career that had me crossing ponds, mostly in a 747c

    Please keep up the good work.
    Tom McIntyre

  13. Dennis Fetscher
    Dennis Fetscher says:

    Great recreation John Dill of marvelous experiences not to be forgotten by me or any of my shipmates. We too, early 60’s, Pacific transits, using every resource available beyond Ocean Station November in the case of Hawaii. Too bad P8 sailors will miss all the fun.

  14. Jerry Lewis
    Jerry Lewis says:

    This brings back fond memories of my time in a P2V-5 while attached to VP-5. I too flew out of Key West during the Cuban Missile Crisis and also the North Atlantic. I also flew C-118’s with VR-21 out of Hawaii during the late 60’s. Again the only over water navigation was the Sextant and Loran. We stayed over water on most of our flight which lasted from 8 – 10 hours. As part of the enlisted crew, we trusted our Navigator.

  15. Bruce Gessel
    Bruce Gessel says:

    Good story. My job from 1962 to 1970 was transport navigator in C-124 and C-141 out of Travis AFB and McChord AFB. I did a combat tour in 66/67 flying the Douglas Racer. I remember well flying in the clouds for hours ferrying the EC-47 over the Pacific. The C-124 was also mostly lost too. Never missed an island and never got an ADIZ violation.
    Would do it again in a second but would have trouble getting in the airplane.

  16. Bob Cloud
    Bob Cloud says:

    I really enjoyed reading this. I flew as air crewman, 4th Tech, on the Lockheed P-2V-7 Neptune from 1959 thru 1963. The squadron was VP-18 out of NAS JAX based in Jacksonville Florida. We were locating and tracking the Soviet subs and freighters during the Cuban Missile Crisis. Your description of a typical flight was almost identical to my daily routine. Looking back they were good days. Heavy on the “looking back” you understand.

  17. Pete Speth
    Pete Speth says:

    Ah, I remember the P2V-7 days & the periscope sextant fondly (VP-17, 65-67). However I would have given a million bucks for even the most basic Garmin GPS at 0’dark thirty some storm tossed nights @ 300′ over the Sea of Japan somewhere between Japan and Vladivostok looking for soviet subs. I’m almost embarrassed by the nav/geo info available, with wx, on the ‘old’ Garmin in my C-182E.

  18. Richard Pickering
    Richard Pickering says:

    Thanks for the story. I flew the P2V-2, 3, 3W and 5F as a Naval Aviator. I have 4500 pilot hour. I started out in 1950 as the navigator for my deployment with VP-6 during the Korean War. My next deployment in 1951 was as the co-pilot for the XO, Commander Perkinson. I was very lucky that I missed the last flight on this deployment because I was selected to return to Hawaii with the advanced detachment. Unfortunately they had to ditch due to an engine failure at night and in bad weather. Commander Perkinson and the radioman were killed. The rest of the crew were saved by an Australian destroyer. My next deployment was to the land of the Beauty and the Beast, Alaska, as the Plane Commander of crew 12. Next I spent 3 years as a P2V instructor at NAS Hutchinson, Kansas. Then back to Hawaii flying in VP-22. Many stories but enough. I am living my 90th year.

  19. Melvin Gary Twite
    Melvin Gary Twite says:

    A great article by John Dill that brought back a lot of memories, one of which involved navigation. I was a radar operator with VP-22 from 1962-64 and we were flying off the coast of Russia and for some reason they wanted to navigate without my APS20 radar.
    After awhile the pilot called me and said Vladivostok looks awfully close and that I should check the distance with my radar and it turned out we were only 20 miles out and a few minutes later we had a Mig on our wing with the pilot indicating that we should leave the area. We did!!!
    Another nerve wracking time was when I had to change the big bottle of the APS20 radar in flight. The radar well had to be 125 degrees Fahrenheit and I was sweating like you know what and hoping everything was discharged, but everything turned out alright and we finished the flight.
    Lots of long Navigation flights, losing hydraulics and pumping the gear down by hand, R&R in Hong Kong, I would do it all again in a heartbeat.

    • Dick Gray
      Dick Gray says:

      Another nerve wracking time was when I had to change the big bottle of the APS20 radar in flight. The radar well had to be 125 degrees Fahrenheit and I was sweating like you know what and hoping everything was discharged, but everything turned out alright and we finished the flight.

      I was a NosePicker, which may explain it, but what was the ”Big Bottle” you had to change in flight on the APS-20?
      And I assume you must have carried a spare “Big Bottle”?

      I know there was a lot of swapping between Fwd & Aft Radar’s on the P-3’s, but I think replacing a tube was about as “deep” as I remember us going on the P-2?

      • Melvin Gary Twite
        Melvin Gary Twite says:

        First of all the big bottle was located in the high voltage container in the Radar well of the P2V. It’s actually called a magnetron which is a large vacuum diode and if I remember right it was about four inches in diameter and about fourteen inches high. The Radar well in the P2V is very hot with all the electronics in there plus both the high and low voltage power supplies are cooled by Glycol pumped thru their covers. When removing the high voltage cover a rod comes up and supposedly discharges the 20,000 volts needed to operate the big diode but to make sure it’s discharged you also do it manually with a long screwdriver. Unbolt the diode, replace, and put the cover back on and the flight goes on.

  20. Scott Erickson
    Scott Erickson says:

    Hi,
    Do any of you guys know how Navy attack planes navigated during Vietnam? I know that USCG had good loran stations in Japan and I believe there was coverage in Vietnam. Did attack planes follow loran lines in dark or clouds to simplify navigation?

  21. Joshua
    Joshua says:

    Great article! Thanks for all of this information. Ironically I read this article from a jet with WiFi. Crazy that I can just pull out my phone and know exactly where we are at- especially in light of all you did back then to determine position.

  22. Oleguer Nogues-Correig
    Oleguer Nogues-Correig says:

    John,

    Well written and charming article, I enjoyed reading all through. Thanks for sharing your life experience and memories with us.

    Cheers,

  23. James Crow
    James Crow says:

    Wow! This really took me back.. It’s been a long time since I heard from another P2V Jockey.. Tales of navigation errors and how we learned to recover from them. And, the sheer terror when you’re 400 NM off-course and made it home on fumes.

  24. JIM SWARTHOUT
    JIM SWARTHOUT says:

    GREAT ARTICLE. MANY MEMORIES. I WAS IN VP-5 FROM 55 THROUGH 58. LIOKE YOU, I WAS RADIO OP ON CREW 5 & 10. BACK THEN WE CARRIED 3 TECHS ( AT) AND WE DID IT All. ALWAYS IN THE ATLANTIC AND THE MED. AND THE NORTH COUNTRY. YOUR ARTICLE TOOK ME BACK INTO DREAM LAND. GREATEST TIME OF MY LIFE. STILL IN CONSTANT CONTACT WITH A FEW GUYS I FLEW WITH. MOST ARE ON THAT ETERNAL PATROL NOW. THANKS FOR THE MEMORIES.

  25. Dave
    Dave says:

    Great writing! I did three tours in Vietnam flying in a P-2V. Just for fun when we were flying from Iwakuni to Misawa Japan we went up to 10,000 feet, turned the radar on high sector scan and flew straight toward Vladavostoc Russia. Once their radars came up we hit the deck but were able to map their radar stations. One of our crews did spot a north Vietnamese trawler trying to deliver supplies to the Vietcong. The squadron tracked it for several days. When it made its run to the coast they turned it over to a destroyer that blew it to bits. Long time ago but the memory lasts.

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