Introduction
The historical long distance flights of American aviators during the past few months have been so close together that the enthusiasm about one hardly had time to subside before the world was thrilled by the next. Such a sequence of great aerial achievements has led a large percentage of the people to believe that nearly all of the problems of the air have been solved definitely and that only minor details have to be worked out before transoceanic aerial lines are commercially practicable. Certain pessimistic reactionaries take exactly the opposite viewpoint and claim that the courageous pioneering flights of this summer’s crop of aerial visitors to Europe are nothing other than “stunts” accomplished more by luck than anything else.
Neither attitude is correct. In order that we may not be misled by the over enthusiastic views of the optimists or the pessimistic statements of the mental dyspeptics let us analyze in detail the conditions that governed the flights of Nungesser, Lindbergh, Chamberlin and Byrd.
The Flight of Nungesser and Coli
In this analysis the following assumptions are made: first, that the French aviators were not forced down in mid-Atlantic by engine trouble, stress of weather, or other emergency; and, second, that the confirmed sighting of the White Bird at the mouth of the Shannon River indicated that the navigator, Coli, was carrying out his announced intention of following a modified great circle course to take advantage of weather conditions. (See Charts No. 1 and No. 2.) The course that Coli started to follow was a great circle course from Paris to Lat. 550 N., Long. 200 VV., and then to Lat. 550 N., Long. 40° W. and from this spot in mid-ocean a second great circle course to New York City. One point that is rather important is the fact that a great deal of the pessimism about their fate was caused by the failure of ocean steamers to sight the plane. When it is considered that the route they probably followed being so far to the north of the usual trans-Atlantic steamship lines crossed only the lesser traveled Canadian routes of Malin Head to Montreal and New York to Scotland Firth in only two points, and these were in the following positions: Long. 210 W., Lat. 54°30' N. and Long. 26° 10' W., Lat. 54°50' N., it is not strange they were not sighted.
However by following these courses Coli believed that he would insure favorable winds through his entire route and would pass to the northward of an atmospheric depression just off the coast of Newfoundland. This probable assumption could have been based upon weather advices from the United States Weather Bureau to the effect that he would have favorable winds in pursuing such a course, which assumption was entirely justified by actual conditions.
The latest information received from Paris seems to indicate that, while Nungesser had the benefit of the previous day’s weather map of the American side of the Atlantic, he was without the latest information obtainable on this side on the day of his departure due to unfavorable reception conditions which broke down radio communication.
If this be correct and the French aviators were not forced down, the following is a description of conditions probably encountered. After leaving Paris a gentle following wind of approximately twelve miles an hour aided them for about the first third of their journey. In about Long. 31° W. the wind began shifting slightly to the southeastward and increased in force gradually until darkness. Up until this time a navigator of Coli’s known ability would be taking into consideration the northward drift due to the wind and would make allowance for it, thus maintaining his exact course.
At about darkness they began to come under the influence of atmospheric depression off the coast of Newfoundland which had not moved to the east as much Nungesser and Coli are seen to have flown from Paris with favorable winds from the northerly quadrant of a low centered over the ocean to the west of France nungesser and coli flight as they probably hoped. A little while after darkness, still assuming them to be carrying out the modified great circle course, they would have changed their course to the southward. However, a gradual increase of wind which might have been imperceptible in the darkness and which was encountered about this time, may have blown them off their intended course to the northward. If the flyers continued they would have come close to the center of the depression but would have still had favorable winds. From darkness to dawn they encountered freezing temperatures, sleet and snow. The increase in the velocity of the winds, the lowering clouds and intermittent squalls might have prevented them from following the intended course, or they may have shifted the course at this point to the northward purposely to avoid the storm’s center. In addition, they had announced that in case of bad weather they might change their destination from New York to Montreal.
In either of these two cases, still assuming them to be in the air, they probably encountered the coast of Labrador about midnight Sunday night or shortly after. It is well to call attention at this time to the fact that, passing close to the center of an atmospheric depression, the clouds would be low and, if flying underneath as they undoubtedly were, they would be flying at an altitude not much greater than 1,000 feet. Due to the decrease in atmospheric pressure from that obtaining at Paris when the flight began, their altimeter would give a false reading of from 1,000 to 1,700 feet, depending upon the barometric pressure they actually encountered. What this actual pressure was we can only estimate but it is quite possible their altimeter may have indicated a height of 3,000 feet when in reality they were probably flying less than 1,500 feet above the water.
In the darkness, they probably were not expecting to sight land so early and might have passed over the coast line and proceeded inland without knowing it.
In this case, quite a number of possibilities are apparent: First, that they may have continued on until daylight and discovered themselves inland over an unknown country; second, they may have been forced down by stress of weather inland; third, they may have crashed into the side of a mountain. Labrador, along the part of the coast they probably encountered, is a plateau 500 to 2,000 feet high rising rather abruptly within a few miles of the coast. Inland it is a rolling country and many ridges and hills rise 500 feet or more above their surroundings but in the depressions between the ridge are many lakes. The entire country is well wooded.
Although discovered early, detailed information about the interior of this desolate land is lacking. Jacques Cartier in 1534 called it “The Land God Gave Cain.” Lieutenant Roger Curtis in 1680 described it as “A country formed of frightful mountains, a prodigious heap of barren rock.” The description of Major Cartwright in his diary of 1786 is probably the best. “God created that country last of all and threw together there the refuse of his materials as of no use to mankind.”
Along the coast of Labrador as far south as Cape Race, fields of ice, icebergs and growlers were present and Belle Isle Strait was still blocked with ice. In case the French aviators were forced down in this area, their chances of survival are small. If they encountered the coast of Labrador in the darkness, it is quite probable they crashed against the side of a mountain, as did Major Martin on the Army’s “Round- The-World Flight,” particularly in view of a false indication by their altimeter due to the decrease in barometric pressure.
Another viewpoint which is gaining adherents, as time passes and no trace of the French aviators or their plane is brought to light, is that they encountered an area while passing near the storm center in which frozen precipitation weighted down the plane.
When the surface temperature is close to freezing as it was over a part of their probable track, any precipitation at moderate altitudes is apt to be encountered in the form of sleet or snow. A plane flying through such areas is rapidly coated with frozen precipitation and soon becomes loaded down to a point where it cannot remain in the air.
The experiences of all aviators who flew over the Atlantic subsequent to this flight seem to strengthen the idea that the White Bird was forced down by the weight of caked ice on her wings and fuselage for, despite the fact that they flew later in the year when temperatures were generally milder, Lindbergh, Chamberlin and Byrd all encountered freezing temperatures in the upper air.
Their best chance of survival, considering the known courage and resourcefulness of Nungesser and Coli, the one on which the last faint hope was based, was that Nungesser made a safe landing in one of the many lakes which dot the interior of Labrador. Had this been true, weeks or even months might have passed before they would have been able to make their way to civilization. Little hope is now held out for their safety.
The lessons that this flight demonstrates are:
First, it is at present dangerous for trans-oceanic planes to fly near centers of depressions, particularly when such centers are accompanied by temperatures close to freezing; and second, the extreme importance of detailed weather information collated in a form designed to fit the peculiar needs of the airman; and third, the danger of low visibility conditions due to centers of atmospheric depression close to the point where a landfall is to he made, particularly when the landfall occurs during darkness.
Lindbergh’s Flight
The most marked characteristic of the weather map of the North Atlantic, during the time Lindbergh was making his flight, was an elongated area of high pressure stretching almost completely across the ocean. This insured him generally clear weather with good visibility conditions. Its position with reference to the track of the flight was such that he encountered over the ocean only tail winds which increased considerably his speed over the surface. (See charts No. 3 and No. 4.)
The two areas of depression, one near Labrador and the other near Great Britain, were unfavorable factors but generally speaking the weather conditions were excellent and the winds most favorable. Only the one near Labrador affected his flight unfavorably. This unfavorable influence was manifested, first, by head winds from New York to Cape Breton Island and, second, by the area of sleet through which he passed shortly after leaving Newfoundland and while in the southeastern quadrant of the low pressure area.
The European depression, during his flight, moved southeasterly very accommodatingly and, instead of menacing him with bad weather, actually aided him by affording strong tail winds. One is almost tempted to say that the elements, angered by his audacity, at first conspired to defeat him and were then so impressed by his courage and skill that they decided to follow General Forrest’s motto, “If you can’t lick ’em, jine ’em.”
From press accounts the public is familiar with the actual progress he made, but a study of the winds that affected his speed is of great interest. From New York to Cape Breton Island a head wind cut down his speed over the surface. At that point, it shifted approximately 180 degrees and increased his speed over the ground by approximately thirty-five statute miles per hour. No better illustration can be afforded of the necessity, in long-distance flying, of accepting a minor and local disadvantage to take advantage of a generally favorable condition, than this shift from ahead to a tail wind. From Cape Breton his track was close to the northern edge of the large high pressure area and the winds were almost directly on his tail. As lie approached Europe, the winds continued to assist his progress and intensified in force until, at times, the speed of his plane was increased by as much as forty miles an hour.
One of the greatest things demonstrated by Lindbergh’s lone flight was the fact that conditions aloft are sometimes unfavorable in isolated spots when the surface weather map indicates nothing but excellent conditions. This emphasizes the necessity to aviators of weather information concerning the upper air, particularly where the tracks of the flight approach the arctic regions.
Chamberlin’s Flight
Almost as soon after Lindbergh’s flight as was possible for meteorological conditions to reproduce the favorable conditions that obtained on May 21-22, they did so, and Clarence D. Chamberlin with a passenger took off. Not only was a high of great magnitude advantageously reaching across the entire North Atlantic but its eastern and western limits overlapped considerably the land on each side. Two similar areas of depression, one near Labrador and one near Great Britain, were present but with this difference—the Labrador low was further to the north than during the previous flight and consequently further away from the track of the flight. (See charts No. 5 and No. 6.) In this position not only was the threat of low visibility and precipitation less imminent, but also the winds along the first third of the flight were more favorable in direction than they were for Lindbergh.
Chamberlin experienced the same shift from a head to a tail wind as his predecessor, but the shift occurred near Cape Sable instead of at Cape Breton Island. This meant that he bucked head winds two hours less which gave him two hours longer with favorable winds. Had both Chamberlin and Lindbergh been competing in identical planes with the same fuel capacity, this difference in wind conditions would have enabled Chamberlin to fly about 100 miles further than Lindbergh could have flown.
While passing through the southeastern quadrant of the Labrador low, Chamberlin encountered a little bad weather with some sleet but compared with Lindbergh’s dose it was very mild, due to the fact that while Lindbergh flew as high as 10,000 feet, Chamberlin kept close to the surface. While the surface temperatures in Chamberlin’s case were lower over this leg than those which Lindbergh experienced, Chamberlin by flying low escaped a lot of the sleet that so nearly caused Lindbergh to turn back.
All across the Atlantic conditions were ideal—weather clear and the winds highly favorable, though east of the thirty-fifth meridian they were not as strong as on the previous flight. This factor, and in addition the slower speed of the Columbia, accounts partially for Chamberlin’s slower time over the ocean.
The cool air coming from the northwest has reached Hungary. It has added new energy to a weak low which yesterday was over Hungary and Poland. In consequence it has widened and extended northward. In western England a rain zone has appeared which apparently belongs to a disturbance still located over the ocean. We need not figure on an immediate change in the weather for the worse. Prospect for middle north Germany to Monday night:
Varying cloudiness without appreciable precipitation; fairly cool.
But while weather conditions were very favorable other factors hindered—the most important being, according to Chamberlin, compass trouble. This, and the fact that he was probably steering a course to the southward to the great circle track to his destination, caused him to sight and pass over the Mauretania in about Long. 130 30' W., Lat. 47° N. When he passed over the Mauretania he flew low enough to recognize that ship.
It is understood that at this time lie was uncertain as to his exact position. He had a copy of a New York newspaper of the previous day, giving a chart which showed the approximate position of various ocean liners crossing the Atlantic. By means of this chart, he was able to correct his course by heading for the southwestern end of England.
This navigational procedure, while highly ingenious and for which he deserves great Credit considering the circumstances, is not one to be recommended for general use. As he proceeded along his route during the night of June 5, passing over southern England and the coast of France, he reached the end of the good weather area and ran into a little less favorable condition than he experienced over the ocean, due to lower visibility and a little rain. During this period of darkness, he was hindered in recognizing points over which he was passing and was prevented from reaching Berlin. His landing at Eisleben, Germany, due to exhaustion of fuel, was made under these adverse circumstances.
Chamberlin’s inability to reach his exact destination, due to the lessening of the cruising radius of his plane by the lack of adherence to the desired course over the ocean, emphasizes the necessity for navigation on flights of this description. In addition, his flight demonstrates that it is dangerous in aircraft to place entire dependence on one compass or one type of compass. That this lesson has not been lost will be demonstrated by the number of compasses that will be carried on the trans-Atlantic flights which are expected to start sometime this summer.
Byrd’s Flight
The weather map of the North Atlantic Ocean during the time that Byrd and his three companions were crossing is almost exactly like a reflection in a mirror of the map that obtained during Nungesser’s attempt. Outside of the fact that the directions are reversed, a description of the weather for the one fits the other almost exactly. Of course, Byrd’s landfall was made on a well-known inhabited shore, and Nungesser’s on bleak Labrador (assumption); the temperatures experienced by Byrd milder than those which Nungesser probably encountered, and the depression through which Nungesser passed covered a greater area. But these differences, while they influenced strongly the survival of the one and the disappearance of the other, are, for the purposes of this discussion, minor ones.
The general characteristic of the weather map for both flights was an area of high atmospheric pressure, covering the first part of the flight, and an area of atmospheric depression near the two destinations. (See Charts No. 7 and No. 8). In each case the axis of the high runs approximately north and south, and not .across the ocean as was the case in the flights of Lindbergh and Chamberlin, resulting in strong cross winds for both Nungesser and Byrd.
Both Byrd and Nungesser ran into areas of low visibility almost simultaneously with a shift in the wind force, and in Byrd’s case, a change in direction in addition. In each case celestial navigation became impossible and dead reckoning of any accuracy equally so.
Consequently, in spite of the known navigational ability of Byrd, his plane deviated from the desired track. Commander Byrd’s account of the difficulties he encountered give us some faint idea of what Nungesser and Coli experienced. For example, for the rain, fog and mist encountered by Byrd over France, substitute snow, sleet, fog, freezing temperatures and the more rugged and desolate terrain of Labrador, and you have a true picture of the odds against the heroic Frenchmen.
However, Byrd passed through a center of atmospheric depression more intense than that encountered by any of the other aviators. This low, which was centered almost directly over Paris at the time of his arrival, was associated with heavy rain, very poor visibility and strong shifting winds. In fact, the America was the only trans-Atlantic plane which passed through the very center of a storm and survived.
Conclusions
A discussion of the present feasibility of regular trans-Atlantic flying is out of place in this article but certain sets of pertinent facts may be collected from these flight analyses. These are as follows:
- The great importance of weather information ;
- The scarcity of good weather over the trans-Atlantic flight routes;
- The paucity of weather reports from ships;
- The great value of aerial navigation on such flights;
- The necessity for information concerning movement of the upper air;
- The obvious value of radio; and
- The effects of surface temperatures near freezing.
Volumes might be written discussing each of these points but only a brief dissertation of each is possible here.
In the first place, considering the present state of development of aviation, the weather along the proposed route is of primary importance to long-distance aviators. Wind conditions vary so greatly over the North Atlantic that, with the extra fuel that can be carried on the planes of today, the margin of safety is so small that it can be easily wiped out by unfavorable winds. Storm centers cannot be entered with impunity nor are low visibility conditions overcome without great difficulty. On the whole, it is not too much to say that for the present, the weather and weather information on a trans-Atlantic flight form the primary consideration.
While weather conditions over some oceanic routes are almost uniformly favorable, over the North Atlantic the aerial routes are not so favored. The five months, from May to October, are generally the most favorable, but this year, between May 1 and July 15, conditions have been favorable for an eastward flight across the Atlantic on only four occasions and for a westward flight but once. To demonstrate how advantage was taken of these days let us list them.
The most favorable day of all that was available for trans-Atlantic flight was the day utilized by Chamberlin and Acosta to establish a new world record for sustained flight (over Long Island).
The next most favorable day, with regard to good weather and high visibility but second with respect to the help afforded by favorable winds, was June 4-5, when Chamberlin made his flight to Germany.
The day which ranked next, with respect to absence of bad weather but which afforded greater help from tail winds, was May 21. It is hardly necessary to state that this was the date of Lindbergh’s flight.
The least favorable day of all, both with respect to weather conditions and aid from wind direction and force on which a trans-Atlantic flight might be considered even possible from the weatherman’s standpoint, was June 30-July 1, when Byrd was in the air.
For a westward flight, while the day of Chamberlin’s flight might have been utilized for the westward hop had a plane of 4,500 statute miles radius been available, only May 4-5, when Nungesser and Coli were undertaking their ill-fated attempt, could be considered at all favorable. In fact, while a storm center was located on the route, the weather conditions were more favorable, as a whole, for the westward flight than they had been for ten years. This is the opinion of no less an authority than Mr. Charles Mitchell, forecaster of the Weather Bureau in Washington.
So with only five days of favorable weather during a period of two and a half months, good flying weather over the North Atlantic is at a distinct premium.
In addition, all of the flyers labored under the difficulty of incomplete weather information. In spite of the publicity given the several flights and efforts made by various agencies, only a small percentage of the ships en route on the days in question gave weather information in time to be of value. The following table is eloquent.
Flight Ships en route equipped with radio Ships equipped with radio reporting
Nungesser 26 6
Lindbergh 32 5
Chamberlin 29 0
Byrd 33 7
From a naval standpoint the two remaining points are the most important. The first is the value and necessity of aerial navigation. To the layman and to a large portion of the aviation world aerial navigation means dead reckoning. Even the few that know astronomical observations are possible believe that the flights of Lindbergh and Chamberlin demonstrate that such observations are not essential.
And the direct opposite of this belief is the truth. For example, take Lindbergh’s flight. He had no navigational equipment other than compasses and a chart showing the courses to be steered. Tie winds he encountered blew almost directly parallel to his courses. While on the first leg of his flight he encountered a small southeasterly drift, this was compensated for by a northerly drift he encountered over the ocean. Therefore the only factor tending to make him deviate from his track was his steering error. Colonel Lindbergh is a superb flyer, trained in the hard school of the air mail pilot. Consequently his steering error was practically nil and his landfall was only three miles from the desired point.
Chamberlin, without navigational equipment and while probably almost as expert a pilot as Lindbergh, was about 450 miles south of the great circle course to Berlin, when lie sighted the Mauretania and was able to check his position by consulting a newspaper chart giving the approximate position of the ocean liners the preceding day. This undoubtedly was due to the failure of his compasses to function to his satisfaction and to other factors.
Had Lindbergh encountered the cross winds that Byrd did, the Spirit of St. Louis would have been blown off her course as far as was the Columbia in spite of the perfect piloting of the man controlling her destinies. And had Chamberlin encountered the poor visibility conditions that hindered Byrd and been unable to sight the Mauretania, it is almost certain that his courageous flight would have ended in disaster.
By no means, the least of the many services that aviation owes to Charles Lindbergh was the warning he issued to the aviation world in general, and to the many flyers about to attempt a flight to Hawaii in particular, that transoceanic flights, and more particularly the Hawaiian flight, should not be attempted without a skilled navigator and complete navigational equipment, by which, of course, he meant astronomical observations.
As an important aid to aerial navigation, information concerning the movement of the upper air would be of great value. The observations of wind velocity and direction at various flying altitudes should be collected and published in the form of pilot charts, similar to the pilot charts showing surface wind conditions and other information now published by the Hydrographic Office. Unfortunately, the information essential to the compilation of such charts is almost totally lacking, and there is no prospect of such information becoming available for some years. In all probability international cooperation will be necessary for the successful undertaking of this project.
The American flyers experienced on an average five hours and twenty-five minutes darkness over the ocean, sunset coining just after taking departure from Newfoundland and sunrise over the ocean about 500 miles to the eastward of Newfoundland. The remaining darkness for them was over Europe and adjacent waters, Lindbergh experiencing only a couple of hours while Chamberlin and Byrd “spent the night” above those waiting to receive them. Nungesser and Coli, on the other hand (according to assumption made), experienced about sixteen hours of darkness beginning in mid-ocean.
These factors, which cover only the navigation and weather features of transoceanic flying, indicate clearly that the problem is by no means solved; but the authors feel that within fifteen years, an aerial route across the North Atlantic will be regularly traveled. If the route is not a non-stop one along the great circle course, it probably will be from New England or Canada to the Azores and thence to Europe for the eastward flight, and from Europe to the Azores and thence to some point in the southern United States for the western flight.
In addition, the prediction is hazarded that the planes operating on these routes will be capable of arising from and alighting on the water. While the exigencies of war sometimes require a sacrifice of safety for a gain in performance, no such necessity exists in time of peace or for passenger-carrying planes.
It is most significant that all of the transoceanic flyers who lost their lives did so in landplanes while in no instance has a pilot engaged on a similar flight in a seaplane failed to be rescued when threatened with disaster.
Towers, Bellinger, Locatelli, Rodgers, Snody and De Pinedo flying in seaplanes were all saved. Nungesser, Coli and St. Romain flying in landplanes have disappeared and probably have paid for their audacity with their lives. The action of the French government, in forbidding any of its official planes lo attempt over-water long-distance flights without flotation gear, is a positive indication that future commercial development in transoceanic flying will concern mainly that symbol of safety— the seaplane.