trical conductors in contact with broken gasoline feed pipes which spread throughout the keel. There was no fire in the after part of the ship from which four of the fire survivors escaped. "That the requirements as to the maximum height and speed, together with the limits of length imposed by the only available construction sheds, necessitated the utmost economy at Hull in the matter of weights and materials. Many new features were introduced in the design, and it appears evident that in some cases there was a lack of vital aërodynamical information as to the effects of these modifications on the strength of the structure.

"That having regard for the great differences in requirements between His Majesty's airship R-38 (the British name for the ZR-2) and previous British airships, the design should have been examined and discussed by an official and competent committee before actual construction was commenced

"That, although there can be no doubt that efforts were made toward the end to complete the ship in the shortest possible time, there is no evidence that the work on the hull or structure suffered." CONSTRUCTION OF ZR-1. In addition to the European airships ordered or under test by the United States Navy there was under construction during the year the ZR-1, which was the American Navy's first attempt to develop a huge airship of the rigid type along the lines of the German Zeppelin L-49, which was captured intact during the war in France. This German craft, built after some 140 airships had been employed in actual service, was considered to represent the best construction of the Zeppelin engineers and works and was regarded as a safe and reliable craft. On this design as a basis the American engineers were proceeding with the idea of making improvements suggested by experience rather than radical innovations. The construction was hampered by reduced appropriation, but the duralumin for the girders of the ship's frame work had been delivered to the Philadelphia aircraft plant of the Navy where it was being fabricated into the lattice work frame members. The contract was let for the eighteen gas bags, while arrangements were being made to lay the keel in the new hangar which had been built at Lakehurst, N. J., and completed during the year to house both the ZR-1 and ZR-2. Here the frame members which had been cut and assembled for fitting at Philadelphia were to be transported and then reassembled and placed in the ship. The ZR-1 had a length of 645 feet and a diameter of 78 feet, both the German standard dimensions, and was to be equipped with six Liberty engines, each of 400 horsepower and in a separate car as against the original plan of five engines. These engines in service were to be reduced to 320 horsepower each with a promised increased economy and reliability of operation, The ZR-1, whose gas bags were designed for either hydrogen or helium, was to have a gas capacity of 2,000,000 cubic feet or some 700,000 cubic feet less than the ZR-2, while her lift was planned to be about twenty-seven tons less than that airship and be about equivalent to the fiftysix ton pull of the British R-34 which made the transatlantic trip. The speed was also planned to exceed the 60 mile maximum of German airships.

U. S. AIRSHIP "ROMA." In the autumn of 1921 the large semi-rigid dirigible "Roma, purchased by the United States government from Italy, arrived in good condition and was assembled at Langley Field. It was found that the envelope which contains the gas was in exceptionally fine shape, and no difficulties were encountered in its inflation, or in assembling the keel and the six power units, so that by November the airship was ready for trial.

The "Roma" was said to possess a range of action of approximately 3500 miles at 80 miles per hour, while at cruising speed, a distance of 8000 miles was estimated. Its capacity was 1,200,000 cubic feet, length 410 feet, width 82 feet, height 88.6 feet, and useful load in the neighborhood of 19 tons. It was equipped with six 12-cylinder, 400 h. p. Ansaldo motors but later it was proposed to substitute Liberty motors of corresponding horsepower for them when they would require replacement.

It was proposed by the Army Air Service to use this ship, which under favorable conditions was capable of making a non-stop flight from the Atlantic to the Pacific coast, for such work as long-distance reconnoissance flights, photographic surveys, coast patrol work, and the carrying of supplies for heavier-than-air units.

U. S. AIRSHIP No. A S 1504. The first test flight of the Army Airship No. A S 1504, a Goodyear pony blimp of the A A type, was made at the Goodyear Akron Air Station September 12, by Flight Officer Lieut. G. W. McEntire. This airship had a capacity of 35,000 cubic feet of gas and was 95.5 feet long, with a maximum diameter of 28 feet. The car accommodated two or three passengers and was equipped with a Lawrence three-cylinder 50 horsepower motor, giving a cruising radius of 450 miles.

This ship was flown to Dayton, Ohio, on September 19, to be used by the Engineering Section of the Balloon and Airship Division of the U. S. Air Service for experimental purposes.

A GERMAN ZEPPELIN FOR THE UNITED STATES. Towards the close of 1921 it was reported that the Allied Council of Ambassadors in Europe had agreed to permit a modification of the protocol signed in June whereby Germany was limited as to the size of airships it might build. In place of the 30,000 cubic metres maximum capacity thus permitted Germany was to be allowed to build for the United States an airship of the L-90 type at the Friedrichshafen hangar after the completion of which the hangar, the largest in Germany, was to be taken down and the machinery and personnel dispersed. This was considered both in the way of a diplomatic triumph for the United States and as an evidence that the American authorities were convinced of the usefulness of these huge aircraft. It was also stated that this new airship would be built without cost to the United States as the expense would be figured in the war settlement.

Assuming that this proposed Zeppelin would reproduce the German L-70 class there would be involved an airship measuring 743 feet in length, or 48 feet longer than the ill-fated British ZR-2, described above, but having the standard German diameter of 78.4 feet. These Zeppelins were capable of sustaining a total useful load of more than 88,000 pounds, equivalent to 59 per cent of the total weight of the ships. Each carried a crew of thirty men. Seven Maybach engines of 290

horsepower each were installed in six power cars suspended below the gas bag of the ship, two being placed in the after car, thus giving a total horsepower of 2030, and developing a speed of over 80 miles an hour. It was decided that the construction of the new Zeppelin should be under the direction of technical officers of the U. S. Navy, and when finished it would be taken over and navigated to America by an American Naval crew. In this connection towards the end of the year it was reported that engineers of the Zeppelin Airship Building Co. were in the United States discussing plans for a possible transatlantic fleet of passenger and mail airships to operate between Germany and America.

HELIUM USED IN AN AIRSHIP. The first successful use of helium as a substitute for hydrogen gas occurred on Dec. 1, 1921, when the U. S. Navy non-rigid airship C-7 was successfully inflated and made two successful trips from the naval air station at Hampton Roads, Va., which were repeated on the following day and subsequently. This large blimp, which had a capacity of 181,000 cubic feet, was filled with gas made at the U. S. Government plant at Fort Worth, Texas. This installation was developed during the war when it was found that by a special process helium could be obtained in commercial quantities from the oil from certain wells in the Texas and Oklahoma fields. In this large plant built during the war for the joint use of the Army and Navy at heavy cost, by means of a complicated refrigerating equipment the helium could be separated from the other gases and made available for lighter than air flying machines. It has the distinct advantage of being non-inflammable and will not explode, but it has 92 per cent of the lifting power of hydrogen. Furthermore it is but 62 per cent as diffusive as hydrogen, which notwithstanding the airtight material of the envelopes often seeps through and goes to waste. Helium also does not deteriorate as rapidly as hydrogen which becomes impure when long kept in a dirigible, as it does not absorb the impurities as readily. In addition to the installation at Fort Worth there was under construction at Langley Field a plant for the production of the gas in usable form for the airships, while another helium producing plant was proposed for location on the Pacific coast. Later in the year the C-7 made a trip to Washington and other flights.

A NEW ITALIAN DIRIGIBLE. The success of the giant semi-rigid airship "Roma" sold by Italy to the United States Government, led the Italian air authorities to build another on much the same design, only larger and better, profiting by experience. It was to be known as the Napoli" and probably was to be the second of a large fleet of huge aircraft.

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The "Napoli" was to be of the semi-rigid type, much the same in shape as the sister airship though more elongated and of 54,000 cubic metres capacity instead of 34,000.

The power plant was to include twelve Spa motors of 300 horsepower each, Italian designed and constructed, and set tandem in the steel ribs so that they could be repaired and even changed, if needful, during flight.

The "Napoli" was designed to carry a hundred passengers. With only four engines working its speed was expected to be forty-three miles an hour.

SPAIN-ARGENTINA AIRSHIP SERVICE. The most notable airship project discussed during the year was an air company affiliated with the Compañia Transatlantica Shipping organization to operate passenger and mail Zeppelins between Cadiz and Buenos Aires, making the trip between the two cities in ninety hours. Application for a subsidy was to be made to the Spanish parliament. The enterprise was Spanish in its inception and development with Major Herrera representing the government, but the organization and management was to be German with Dr. Hugo Eckner formerly with Count Zeppelin as chief of the technical staff.

Dr. Eckner stated that war experiences with the German Zeppelins were sufficient to enable his company to guarantee the smooth operation of airships of 45,000 cubic metres in size at a rate of speed of seventy-two miles an hour while carrying between thirty and forty passengers and 300,000 letters.

The idea of the Cadiz-Buenos Aires service to establish a quick and direct connection with the trans-Atlantic nations originated in Spain and negotiations with the Zeppelin management led to the organization of a commission, which subscribed 50,000,000 pesetas (about $10,000,000) of the necessary 80,000,000 pesetas (about $16,000,000), the Spanish Government guaranteeing the interest on this sum.

Major Herrera together with two other Spanish air experts, and two Germans, including Dr. Eckner made a trip to Argentina in order to choose sites for hangars, study the conditions, and obtain financial interest and support from the Argentine Government. They reported that it would be necessary to use larger airships than any previously built (with the exception of R-38), and that the weather on the European side was favorable for anchoring but that on the American side it would be necessary to have a revolving shed. Excellent wind and weather conditions greatly favored the route proposed, which was 6000 miles long, and the airships would be able to escape tempests.

The return journey from Buenos Aires to Cadiz would require a hundred hours instead of ninety, owing to the northeast winds that would be met.

It was proposed that the airship service should be started with three airships, which would cost 36,000,000 pesetas (about $7,200,000), and hangars, gas factories and wireless installations, costing 40,000,000 pesetas (about $8,000,000), while unforeseen expenses were estimated at 4,000,000 pesetas (about $800,000).

The cost of each trip was estimated at about 42,000 pesetas (about $8400), and it was anticipated that the receipts would be about 900,000 pesetas (about $180,000) based on carrying sixty passengers at 5000 pesetas (about $1000) each, and 300,000 letters at a special mail rate of 2 pesetas (about 40 cents) each.

FRENCH DIRIGIBLES

The aëronautical station at Orly in the suburbs of Paris was selected to be the principal French airship base; and, during the year 1921, the buildings and plant required for construction were in an advanced stage. They included big gas-holders, airship sheds, and workshops, and a Customs house. Mooring masts for airships were embraced also in the French programme. Under

AIR COMPETITIONS

AMERICAN FLYING MEETS. During 1921 a number of well attended flying meets and competitions were held in the United States. Among the more important were the races, and demonstrations on Long Island, in Florida, Hartford, Conn., Baltimore, Chicago, Kokomo, Ind., Dallas, Denver, Oakland, and Long Beach, Calif., several in Iowa and Nebraska, and one of the most important, the American Legion Flying Meet at the National Convention in Kansas City, Mo., October 31-November 2.

PULITZER TROPHY RACE. The Pulitzer Trophy Contest for 1921 was held on November 3, at Omaha, Neb., over a triangular course of 30.7191 miles with five laps, or a total distance of 153.595 miles. It was won by Bertrand Acosta in a Curtiss Navy biplane with Curtiss CD-12 400 horsepower motor in 52 minutes and 8.4 seconds, or an average speed of 176.75 miles per hour, thus breaking the previous record of 173.1 miles per hour over a 186 mile course made by Lieutenant Georges Kirsch in a Nieuport-De Lage plane at the Deutsch de la Meurthe competition at Etampes, France, on September 30. The result of the Pulitzer Contest for 1921 was noteworthy in that the successful contestant was an American who flew an American plane equipped with American engines. Second place was also taken by an American plane, as Clarence Coombs in the Curtis-Cox Triplane accomplished the course in 54 minutes 6.2 seconds, or an average speed of 170.34 miles. Third place was taken by J. A. MacReady in a Thomas Morse MB-6 biplane with a Wright H-2 motor in 57 minutes and 20.4 seconds: and fourth place by Lloyd Bertaud in an Italian Balilla scout biplane with a Curtiss C-12 motor in 61 minutes 31.4 seconds. James Curran in a S. V. A. biplane went two laps and was forced down by engine trouble, while Colonel H. E. Hartney, whose feed pump failed to work, was injured in a forced landing on the first lap. The 1922 competition was arranged for Detroit, where the 1921 contest was to have taken place, but was abandoned in favor of Omaha as greater support seemed possible in the latter city.

LARSEN TROPHY COMPETITION. This interesting airplane race on November 5 was held also at Omaha, over a triangular course of 8 laps each of 30.7191 miles or a total of 245.753 miles. This was won by E. F. White in a S. V. A. plane which negotiated the distance 154 minutes and 56 seconds, or an average speed of 95.17 miles per hour, though the decision of the Contest Committee was appealed. In this competition the efficiency of the various machines was determined on the basis of the following formula:

For

W = Total Load Leaving Ground Lbs. T= Light Weight of Plane+Water- Lbs. W T= Total Useful Load - Lbs. S= Average Speed, M P H Actually Made. G = Gallons of Fuel Actually Used. WORLD'S ENDURANCE AIRPLANE RECORD. the first time since the record for time of flight by an airplane was made by Wilbur Wright in the early days of aviation (18 seconds in December, 1903, was the first duration of flight for a heavier than air machine) the World's Endurance record was made by an American machine with an American pilot and passenger. On Dec. 30, 1921, Edward Stinson and Lloyd Bertaud were in continuous flight for 26 hours 19 minutes and 35 seconds above Roosevelt Field near Mineola, Long Island, N. Y. This supplanted the previous record of 24 hours 19 minutes and 7 seconds made June 4, 1920, by Lieuts. Lucien Boussoutroli and Jean Bernard at Ville Sauvage la Dordogne flying a Farman Goliath airplane. The American record was made in a JL-6 airplane designed and built in the United States by John M. Larsen; an old metal plane developed from German designs, but with important and extensive modifications and improvements.

The average speed during this flight was estimated at about 85 miles an hour so that the actual distance flown was in the neighborhood of some 2500 miles which is also a record distance for a non-stop flight though of course the course followed was circular with the landmarks and expecially lights below to guide the pilot. This distance may be compared with the Transatlantic flight of Alcock and Brown from St. Johns, Newfoundland, to Clifden, Ireland, of 1936 miles made June 14-15, 1919. The 185 horsepower B. M. E. engine, which was of German design though of American construction, functioned perfectly during the flight and was capable of further effort but defects developed in the lubrication system including a faulty connection so that certain parts had to be lubricated by pouring the oil by hand. The plane was built of duralumin throughout and had a wing span of 50 feet and a length over all of 31 feet by 11 feet in height. Ordinarily its cabin accommodated six passengers, but on this occasion the space was filled with extra fuel and lubricant. The Larsen airplane was one of several that had been constructed and used during the year in long distance flying and the achievement of a world's record came as the well merited result of careful design, construction, and experiment with this type of plane.

AMERICAN SPEED RECORD BROKEN. The American speed record for airplanes made under international standard and official conditions and supervision was broken by Bert Acosta, piloting a Curtiss navy racer, at Mineola, November 22. In this flight an officially timed average speed of 184.8 miles an hour was made and the maximum attained, as checked by electric timing apparatus, was 197.8 miles an hour.

This flight was also noteworthy as the first to be made in the United States since the war under the rules of the Federation Internationale Aëronautique. These rules, which were duly carried out, provided for eight flights over a measured course of one kilometre, four with the wind, and four against.