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Performance Table of Seaplanes, 1914-20.

Boat Seaplanes.

1914.

Type

H.P.

Useful Load In- cluding Crew db.)

Endurance Mrs.

Maximum Speed in m.p.h. at Sea Level

Span

Total Weight*

Maximum Total Weight

Effective Ceiling

Curtiss America. F.B.A

1 80

IOO

650 630

3 3

65 68

76 40

4,000 1,825

4,5oo 2,000

IQI5-

Norman Thompson

1 20

835

4i

78

48

2,600

2,600

ipi6.

Large America. H 12 Porte Boat ....

690 i, 080

1,357 3,900

6

7

97

88

95 124

10,650 18,600

11,000 18,600

10,800 8,000

1917.

A.D. Boat

200

i, 066

4i

93

50

3,56o

3,600

11,500

1918.

F 5 (Light Load). . . Phoenix PS (Light Load) Tellier

720

72O

350

1,607

i,773 2,640

8

7i

6

IOI

i5

90

104

8? 76

9,630 9,210 7,160

13,300 12,500 7, 1 60

17,400 15,100

1919.

Felixstowe Fury F.B.A. . ... Nieuport Macchi N.C Cornier G.S.I. (Zeppelin)

i, 800 200 260 i, 600 520

6,690 1,320

595 12,000 2,800

10 4 3

1

95

87 127

85

112

123 51 40 126

6.5

25,250 3,520 2,245 28,000 9,500

28,000 4,000

2,245 28,000

12,000

7920.

Vickers Viking Mk. III.

450

1,278

4*

121

46

4,900

5,100


 * Total weight carried for performance shown.

The early development of rigid airships was carried out by Count Zeppelin in Germany, and represents an extraordinary record of perseverance. This development was only rendered possible by political influence and by the repeated financial assistance available. The Schiitte-Lanz airships were of wooden construction and developed more slowly. They appear, however, to have embodied considerably more original and perhaps cou- rageous developments than did the Zeppelins, which were de- veloped more as gradual minor improvements on the original design.

British Rigid Airship No. i was started in 1909. During the construction great consideration was given to the various auxiliary gear required by the ship and to the problems included in the handling and mooring as well as the actual flying of the ship. The thoroughness and accuracy with which this auxiliary work was developed is most remarkable in the light of later experience. Before the first flight was made the ship was moored by the bow to a mast with her cars resting on the water. The ship was broken amidships in Sept. 1911 as the result of a mistake in handling while she was being returned to her shed after one of the trials of handling before flight. Comparison of the details and esti- mated performance of this ship with the contemporary Zeppelins shows that she was a remarkably good first design and that had it not been decided to abandon rigid-airship construction the British development of these ships would almost certainly have become at least equal to that of Germany.

British Rigid Airship Rg, by Vickers, stopped at the beginning of the World War, was restarted in July 1915 and made her first flight in Nov. 1916. She made a rather remarkable passage to Howden through a snowstorm over the Pennine range. Being somewhat inadequate in buoyancy, she was used for instruction and ultimately for mooring experiments.

She was followed by four ships of R23 class, built by Vickers, Beardmore and Armstrong, and again by R27 and Rag, which were remarkable for the absence of the keel which had existed in all previous rigid airships and had been looked upon as con- stituting the real strength of the ship to resist bending and shear- ing forces. This keel subsequently reappeared in German Zep- pelins and in the ships built in England, but then merely as a means of distributing to the main frames the weights of petrol tanks, etc., arranged along it.

Two wooden ships, RJI and R32, were built by Short to a design closely similar to that of the Schiitte-Lanz type. They were considerably faster than contemporary ships.

Rigid-airship construction in Germany had advanced con- tinuously and was, therefore, greatly ahead of French and British. A combination of the talent and experience of the Zeppelin and Schiitte-Lanz firms early in 1916 resulted in the design of L3o, giving a speed and performance far ahead of any earlier ships. L$3 of this class was brought down in Sept. 1916 in such a com- paratively undamaged condition that it was possible from her to prepare a design in England to which R33 and R34 were built. These ships were not, however, completed till late in 1918.

The German L65 class marked a further advance in speed and performance, while the L?o class, of which the first ship, L7o, was destroyed on the first flight to England with some of the chief constructional experts on board, marked still further progress in performance and in the simplification of the machinery installa- tion, in the adoption of fins of triangular cross section. 1,72, which was not actually completed until after the Armistice, had again a slightly higher performance.

After the Armistice Germany built a much smaller airship, the " Bodensee," for commercial purposes, and with her carried out a remarkable series of passenger flights. The ship was then enlarged and a sister ship, " Nordstern," also constructed.

Subsequent to the R33 class the British R36 and R37 were constructed to a generally similar design, of somewhat greater capacity and much improved detail. R8o, designed and con- structed by Vickers, embodied several entirely new features, but her size was so restricted by the dimensions of the construction shed that her performance was seriously handicapped. R38 made radical changes in features of design, and a clear and def- inite departure from German methods. The United States had contracted for its purchase. It was to be used, as it was gener- ally understood, for an experimental service from New York to San Francisco and for that purpose masts and intermediate stations were being prepared. R38, while on the final test flight before delivery on August 24 1921, caught fire and fell owing to structural weakness, and many lives were lost.

Non-Rigid Airships. In 1913 the chief general classes of non- rigid airships were: (i) Those with a plain circular envelope from which the car, etc., was suspended from special fittings on