Navigation in the S. W. Pacific

TOLD BY CAPTAIN CARL HEFLEY, NAVIGATOR

NAVIGATION varies in different theaters of operation according to several different factors. These factors may have an influence on the navigator even if the theaters are only a few hundred miles apart. Some of these factors are terrain, weather, types of planes and navigation auxiliary aids. In order that a navigator be able to operate successfully in one certain theater he must receive some specialized training of that theater. This should be given him in the R.T.U. or overseas training unit.

The navigator doesn't necessarily have to know the exact base in which he is being sent but be given training by instructors who have a knowledge of that theater. These men could be returnees or men who had special training in that theater. The navigator should be given flights that correspond to missions of that theater.

The Pacific Theater is composed entirely of small or large islands surrounded by bodies of water varying in breadth from a few miles to thousands of miles. Thereby most of the flying will be over water from island to island or from island to target and back. A large percent of the missions will be fown against shipping and roving fleets. This requires a navigator to know his exact position at all times. Being over water he has to depend on accurate D.R. and celestial.

The ship flown was a B-17F which we figured a range of about 1500 nautical miles with a bomb load. Using a cruising air speed of 165 m.p.h. we were out on most missions for 10 hours or more depending on wind and weather. We also had to fly patrol or reconnaissance missions which even ran up to 14 hours of flying over water for the entire route. In this length of time you would run through a front or two and encounter several wind changes. All of these factors only make the navigator more conscious of his position at all times. In order for him to know his position he must have kept an accurate D. R. and log and applied sunlines whenever possible. The B-17's we used were in an experimental stage of armament and along w ith the changes of bomb loads every day our compasses had large deviations. We had our top gun turret calibrated with an accurate azimuth ring so we could get our relative bearing on a celestial body easy enough. We did not have the astro-compass or a way of mounting the polarius. To swing the compass we simply sighted the guns on the body and got our R.B. off the azimuth ring. Another thing that we had to watch was the abnormal magnetic variation around some of the islands. These factors along with old ships made it very important that we had the right compass heading.

We were briefed for 2 kinds of missions, bombing and reconnaissance. On search or reconnaissance missions we were briefed in the morning before take off. The operations officer and intelligence officer would give us the dope-sheet and go over with the crew what we should find and the places to photograph. They would discuss the possible enemy contact and give us a weather sheet which sometimes wasn't accurate. The metro data wasn't too accurate because of inexperienced men and no weather stations near.

The bombing missions were briefed on the night before the mission. The group C.O. would give us the place time and altitude of the rendezvous point and also the target. He would discuss freely the target and illustrate with photographs and maps. The intelligence officer would give us the dope on gun emplacements and number of enemy fighters to be expected. After discussing these problems the C.O. would then give us the heading for the target. The C.O. then designates the formation leader and flight leaders. The navigators then generally have a discussion as to what course and maps to be used. The Squadron or Group navigator doesn't always lead the task force. The flight leaders will use their own navigators. The navigators got their maps out and drew the course on them.

The mission was generally flown as scheduled regardless of weather or other difficulties. Toward the target the lead navigator assumes the responsibility of leading the formation, while the other navigators follow or track as we called it. Maybe our target was a fleet 600 miles out in the ocean so each navigator must keep a pretty accurate log to the target because of engine trouble or turning back.

When the target has been hit and the formation starts home, most of it will break up and fly individually back to the base. This puts a lot of work on each navigator but makes it easy on the pilot. The navigator has 600 miles of water to navigate over and a small island to hit without radio aids. He doesn't mind for the pilot has shown that he trusted you instead of the lead navigator.

Methods of navigation used were somewhat varied owing to how far or range of the mission from land or check points. If the mission was in a chain of islands then the navigator could use pilotage part of the way. This method was used when the navigator could distinguish the different islands. This kind of navigation was used in the New Guinea Theater. In the Solomons Islands we could use it very little of the time.The method used over water without check points was one of celestial and D.R. Leave the departure point on magnetic heading reading drift after a few minutes away from the island. Cheek your deviation on heading and when 10 or 15 minutes out from land, take a double drift. Sometimes we just read the wind off the water. This was done by watching the white caps on the surface. The navigator could get his ground speed and wind. The navigator checked his course and ground speed by sunlines. Sometimes during the day's flight the LOP's would give good course or ground speed lines. The course lines were needed because we had certain sectors or lanes that we had to cover. Most of the navigators had techniques or methods they used when they missed their destination. A good idea is to work out on the ground just what you would do if a certain thing happened. For example, when weather is bad and you are coming into an island. In the Pacific there are several small islands grouped around most of the big ones. I found that as I came into a certain base and my E.T.A. was up, by running 15 more minutes I would hit some small islands if I were on the left of destination. So if I didn't hit them in 25 minutes then I was on the right and needed to turn 90° left to hit destination.

Night missions were much easier flown than day missions if the weather wasn't too bad. We flew fix to fix thereby depending upon celestial alone. The navigator had to watch his errors because of the equator and international date line. It wasn't so easy where you were crossing them every day. Also he has to know the southern hemisphere celestial bodies well.

We used the mercator maps and V.P. charts along with the larger marine maps. These weren't so very accurate as so much of the South Pacific is unchartered accurately. We also used a mercator map put out by the Navy that covered the area right well .

The radio aids consisted mainly of a small trailer station used for emergency only. You had to ask for M.O.'s or signals and even then they were only given for 5 minutes on the hour. When the signals were on then we knew that a ship was lost. In our squadron when a navigator asked for M.O.'s or signals then we gave him the horse-laugh when he came in. Very seldom did we use the radio for the thought of being disgraced made you navigate more ardently. We used the radio for time ticks for our celestial. The reasons for radio silence were due to lack of equipment and the fear of Japs using our radio facilities. Using the radio could cause you to get tricked by the enemy. The Japs would send out a more powerful beacon near the frequency we were using thereby causing a plane to be pulled away from our base. An example of that: one of our ships flying the beam one night gave out of gas almost at one of the enemy bases. We later found that the enemy was using a beautiful set-up of radio beacons.

Our navigation equipment was kept in our tents and used as needed. We kept our tables and a few other things in the planes. The D.R. kit and octant was kept in the navigator's tent. The octants were the things we took good care of. We had a poor set up for the care of navigation equipment.

Our supply situation was about the same. We drew our maps from the group intelligence. We kept the same equipment we brought with us. The supply situation was very good while we were in the Hawaiian Dept. We had a well stocked air depot and squadron supply at Hickam Field. We had no way of calibrating instruments so we used them as they were. The conditions are better down there now but you will always have poor conditions at the front line bases.

The weather was very poor most of the time. The fronts weren't tropical hurricanes but they were hell to fly through. The fronts would build up in the afternoon and hang over the islands at night. I have flown at night when there was St. Elmo's fire around the prop. The pilots got lots of instrument time while the poor navigator wore out the seat of his trousers and pulled out his hair.

On the whole in the Pacific a navigator needs to know celestial and be able to trust his shots. Pilotage doesn't count much only identifying the islands. These can be identified by their shape.

From June 1944 LOG OF NAVIGATION
Vol. 2 No. 6

LOG OF NAVIGATION is the approved publication of the AAF Training Command. Permission granted to Army publications to reprint if credit line is given.

EDITORIAL OFFICES: Army Air Forces Instructor's School (Navigation) Selman Field, Monroe, Louisiana. Publishing Office: Gulf Publishing Company, 3301 Buffalo Drive, Houston, Texas. ADDRESS all correspondence concerning LOG OF NAVIGATION to Editorial Office.

Lt. Jack J. Wendell.................Log Director
S/Sgt. H. G. Congdon..............Ass. Director
Cpl. John P. Cowan................Art Director
Cpl. R. D. Schoenke...............Special Features Editor
S/Sgt. Arthur J. Daley.............Photo Editor