By Gösta H. Liljequist, Uppsala, Sweden
(INTERAVIA No. 5/1960)
Gösta H. Liljequist, Professor of Meteorology in the University of Uppsala, Sweden, has been interested all his life in polar expeditions and polar history. Born in 1914, he graduated from Lund University in 1937 and became first a hydrologist and later a meteorologist at Sweden’s Meteorological and Hydrographical Office. He joined the 1949-1952 Norwegian-British-Swedish expedition to the Antarctic as meteorologist, spending two years at Maudheim, and was later leader and organizer of the Swedish-Finnish-Swiss expedition to Northeast Land, Spitsbergen during the 1957-58 International Geophysical Year.
In publishing Professor Liljequist’s article, Interavia has no desire to belittle the exploits of Admiral Byrd. The Editors are merely following their normal custom of opening the magazine’s pages to the widest possible range of opinions. They will welcome further details or comments on the «Josephine Ford» flight.
At the end of April, 1926, final preparations were being made at King’s Bay, Spitsbergen, for the start of the dirigible «Norge» on her flight over the North Pole to Alaska, when a second expedition appeared on the scene. This was the American ship «Chantier» carrying the Fokker aircraft «Josephine Ford.» Then on May 7th the Amundsen-Ellsworth-Nobile expedition’s «Norge» arrived in Spitsbergen from Rome.
The «Josephine Ford» was the first to leave. With Commander Richard E. Byrd as leader and navigator, and with Floyd Bennett at the controls, she took off at 0037 GMT on May 9th in beautiful weather. She returned to base the same afternoon, having completed her mission: the first flight to the North Pole.
Two days later, on May 11th, the «Norge» started her flight across the Arctic Ocean to Alaska via the North Pole.
The flight of the «Josephine Ford» is of great interest from both a historical and a technical point of view. It still merits a thorough and objective analysis.
The «Josephine Ford» was a trimotor monoplane, built by the Fokker factories in Holland in 1925. The type was designated Fokker F-VII-3m. It is described in «Jane’s All the World’s Aircraft» for 1927.
The aircraft was equipped with three Wright Whirlwind J-4B engines. They were among the first in the series and had the same maximum output as the J-4A, namely 200 h.p. each at 1,800 r.p.m.
The propellers of the «Josephine Ford» were Reid-Levasseur with twisted steel blades. These fixed-pitch propellers were inferior to the Hamilton Standard Adjustable used with the J-5 engines (240 h.p. each at 1,980 r.p.m.) on the Fokker aircraft which went into production at the company’s American factories in 1927. The American Fokkers had a maximum speed of 119 statute miles an hour.
«Jane’s» for 1927 gives the «Josephine Ford» a cruising speed of 102.5 m.p.h. or 89 knots (165 km/h). This is, however, a sales value. It is doubtful whether it could have been maintained throughout a long flight.
In studying the flight of the «Josephine Ford,» one is immediately struck by the time difference between the outbound and the return flight, 8 hours 26 minutes compared with 6 hours 52 minutes. The difference could be explained by a more or less constant 10.6 knot wind from the north. This would give us the same cruising speed as published in «Jane’s,» 89 knots. On the other hand, the prevailing weather situation would not lead one to expect a northerly wind as an average over the whole route, even though Byrd’s report contains the information that the wind freshened from the north just after the plane had left the Pole. The reports give the maximum speed of the «Josephine Ford» as 117 m.p.h., but do not mention the cruising speed.
In trying to determine the cruising speed of the plane – especially the speed that would have been used on a very long flight– I have analysed both the cruising speeds of the aircraft on actual flights and the results of a test flight.
In the fall of 1927, the «Josephine Ford» was taken on a long tour of the United States, with Floyd Bennett as pilot and Bernt Bal-chen as copilot. The total distance flown was 7,005 nautical miles, and total time in the air was 100 hours 55 minutes. The tour contained 45 stops. The average length of each flight was 156 nautical miles at 1,000– 1,500 feet or lower, and the average time 2 hours 14 minutes.
From the flight log I have computed the ground speed for each of the 45 flights. In 24 cases, the speed was between 66 and 80 knots, i.e. around 72.5 knots. Excluding five flights with very low speed, obviously much wind-influenced, the average speed of the remaining 40 cases is 72 knots. The mean value for all 45 flights is 70 knots.
In other words, the cruising speed of the «Josephine Ford» was around 75 knots or a little lower in the fall of 1927. Just before the tour all three engines had been overhauled at the Wright factories and were in top working condition during the entire flight.
In June 1927, another Fokker F-VII-3m flew from San Francisco to Honolulu, a distance of 2,400 statute miles, in 25 hours 43 minutes, i.e. at an average speed of 81 knots. This aircraft was equipped with more powerful Wright J-5C engines. The plane had a light to moderate tail wind all the way, and consequently its air speed must have been less than 81 knots, say 70 to 75.
During the polar flight, the «Josephine Ford» was equipped with skis instead of wheels, which must have slowed her down by a few knots, particularly as the skis had been damaged in a mishap and provisionally repaired with oars. It seems a logical conclusion that the average cruising speed of the «Josephine Ford» on the North Pole flight was about 70 knots. This is a rather different figure from the 89 knots published in «Jane’s.»
In order to determine whether this low cruising speed may be considered reasonable, I have made a study of the performance qualities of the Fokker F-VII-3m. My data are obtained from a verified test flight made on October 29th, 1927, at the Naval Air Station at Anacostia, D.C., with an American-built Fokker with Wright J-5C engines. The propellers were Standard Steel Adjustable, superior to those of the «Josephine Ford.» This aircraft reached a maximum speed of 118 m.p.h. and consequently the maximum speed of the «Josephine Ford» must have been lower than 118 m.p.h.
This test flight was of course performed with a wheel-equipped aircraft. By substituting skis for wheels the parasite drag is increased. A technical expert has assisted me in obtaining a rough value for this increase from photos of the plane in «Jane’s» and Byrd’s report. The results of the calculations show that in the ski-version the speed is slowed down between three and four knots, depending on the power of the engines.
During a flight, only about 60 percent of maximum available power ought to be taken out for any length of time. For very long flights even this is a somewhat high value. With an output of 60 percent of available power, the speed of the ski-version of the aircraft is found to be 72 knots, as compared with 75 knots for the wheel-version.
The values obtained from the actual flights are thus verified. If we assume the cruising speed of the «Josephine Ford» to have been 75 knots, we have made no underestimate.
Let us now consider the weather conditions during the flight. At the time, meteorological observations were made from Spitsbergen, from northern Russia and from a few places along the Siberian coast and Alaska. They suffice to reconstruct a weather map with a reasonable degree of correctness.
North polar flight of the «Josephine Ford» (extract from National Geographic Magazine, September 1926, p.386).
I have studied the American Historical Weather Maps for the Northern Hemisphere, which give daily synoptic charts for 1300 GMT and also synoptic charts for 0100 GMT analyzed at the Norwegian forecasting centre at Tromsø, where at the time special attention was paid to Arctic weather conditions in view of the «Norge» flight. The two sets of charts differ in details, but are the same in all essentials.
Both show that an anticyclone covered almost all of the Arctic, with a high-pressure ridge extending via the Barents Sea to eastern Russia. This remained stationary from May 8th to May 10th and must have been situated north of Spitsbergen, where easterly to southeasterly winds prevailed.
Estimating wind directions and speeds from the two charts, we find that the Tromsø chart indicates SE-ESE winds of 10 to 20 knots at King’s Bay, very light southerly winds between 80º and 88° N and poleward winds from Greenland of about 10 knots in the Pole area. The Historical Weather Maps confirm this picture, though they give the direction of the poleward winds in the Pole area as coming from eastern Alaska or western Canada. These winds refer to 2,000 – 4,000 feet, where the plane stayed during the flight.
The inference is that the flight may be considered as having taken place in a no-wind atmosphere. At any rate, had a wind worth mentioning arisen between the Pole and Spitsbergen, it should under no circumstances have been found south of about 85° N, since the ridge remained stationary.
On the flight north, Commander Byrd made six astronomical observations with a bubble sextant on the route between Amsterdamøya and the Pole, and four more at or near the Pole. None were made on the homeward flight, the sextant having been damaged.
However, in making an analysis of the flight only the speed of the plane, time and distance plus wind and/or weather conditions are of objective value.
We possess one certain fix on the northbound flight: the northern point of Amsterdamøya at 79° 47′ N. The plane left King’s Bay at 78° 55′ at 0037 GMT, passed Amsterdamøya at 0122 GMT, reached the Pole at 0903 and left it again at 0915 GMT. For the homeward flight the only time notation is that Grey Hook (Gråhuken) was sighted straight ahead at 1430 GMT. The time of arrival at King’s Bay is not given.
Byrd gives the flight time as «nearly sixteen hours,» and Amundsen has written that the returning aircraft was sighted just after 1600 GMT, while Balchen, who was a member of the «Norge» expedition, gives the time of arrival as 1607 GMT. Accepting 15 hours 30 minutes as total flight time and subtracting the 12 minutes spent over the Pole, we arrive at an average ground speed of 87 knots (100 m.p.h.) for the total distance of 1,330 nautical miles.
With our estimated speed of 75 knots, the «Josephine Ford» could in 15½ hours have flown not more than 1,162 nautical miles, bringing it not farther north than 88° 36′ N. Allowing for delays in climbing, the time spent circling over the Pole and the detour around Amsterdamøya on the return flight, a time of 15 hours for the direct flight north and back is more probable. This would have brought the «Josephine Ford» to a point 88° 17.5′ N. To have reached the Pole, the aircraft should have returned to King’s Bay between 1830 and 1900 GMT, not a few minutes past 1600 GMT.
The discussion has until now been limited to ground speed in a no-wind atmosphere, conditions which would appear to have prevailed according to the synoptic weather charts.
To have reached the Pole, the plane would have had to have a tail wind of about five knots as an average for the outward flight, and the wind would also have had to change direction and increase to about 22 knots as an average over the entire distance from the Pole to King’s Bay on the homeward flight. As already mentioned, the fresh winds can have occurred only during the first half of the homeward flight, in which case they would have had to reach at least 40 to 50 knots from the north.
Such a strong northerly gale should have made itself felt at Spitsbergen soon afterwards, which it did not. The whole of the Arctic was covered by an anticyclone, and a 40-50 knots gale close to this high pressure area is highly improbable.
Commander Byrd’s flight in the «Josephine Ford» gave inspiration to a generation of men interested in polar work. However, it would seem appropriate that a committee of aeronautical and meteorological experts be given access to the flight log and all available data to study the question whether in actual fact he did reach the Pole.