November 10, 1942
Tests of Saul-Vangrow Kite K-1 at
HMC Dockyard, Halifax, N.S.,
November 2nd and 3rd, 1942
In accordance with instructions, the undersigned proceeded to Halifax, N.S., to witness the subject tests.
The tests were conducted under the general direction of Lt. Com. A.E. Woodward, R.N. Rtd., Senior D.E.M.S. Staff Officer at the H.M.C. Dockyard. Sub-Lieutenant Kendrick was assigned to make arrangements for and take charge of the tests. The observers of the tests were M. Vangrow and E. E. Martinsky, representing the manufacturer and the U.S. Maritime Commission, respectively.
The kite was developed by a Mr. Saul and has been and is being used commercially for the display of aerial advertisement on the Pacific Coast. Mr. Saul affiliated himself with Mr. Vangrow of Dayton, Ohio, and they have formed a company called the Saul Vangrow Manufacturing Company. It is understood that extensive tests have been made of the kite at Fort Sill, Oklahoma, by the U. S. Army. Mr. Vangrow arranged the subject tests to demonstrate the usefulness of the kite on shipboard as a protection against bombing attacks. Request has been made of Mr. Vangrow to furnish the Commission with a copy of this report of tests when it becomes available.
Lt. Com. Woodward pointed out that the kites are deemed useful only as a means of protection against low level bombing attacks. Therefore, the kite would be tested only to elevations not exceeding 1,000 feet.
There were two size kites designated K1 and K2. The larger kite, K2 was not flown because its size did not lend itself to assembly on board ship, and further, considerably more relative wind is required to fly it. Neither specifications or plans of the K1 kite were available for inclusion in this report, but they have been requested of Mr. Vangrow. Two photographs are attached as exhibits.
The K1 kite is of the boxtype of construction with four cells forward and two cells aft and a five strand bridle fastened at ends of each bottom longitudinal member. The span is about 13'-6" and length of kite about 10'-3". The cells are all of the same size which makes the diagonal braces interchangeable. The kite when knocked down may be rolled up to about 6" diameter, and to the length of the six longitudinal sticks joining the forward and aft sections of the kite. Short sticks are run longitudinally in way of the outer cells in forward wing. A vertical centerline stabilizing wing is fitted extending from forward end of kite to forward end of aft wing section. All sticks are of long grained spruce, and the diagonal braces are of airfoil shape to increase the lifting power. A stranded wire is sown in the leading and following edge of the canvas kite fabric. Vertical sections of wire are located five locations where there is no canvas to take the tension caused by inserting the diagonal braces.
To assemble the kite the two vertical struts are inserted at the ends of the stabilizer wing. Working out of the centerline, the diagonal braces are sprung into place, the V cut in the end of each fitting snug against the square, longitudinal pieces. A circular section wood rod is lashed to the center of each group of four cell braces to hold them in line. The weight of canvas used is not known at this time.
All the six long and four short longitudinal wood members are secured permanently to the kite fabric. This leaves 24 diagonal braces and 6 auxiliary fore and aft braces which require to be fitted to assemble each kite. During the tests there was no opportunity to ascertain the length of time needed to assemble the kite, and it is hoped to obtain the same during the further experiments being carried out. Mr. Vangrow stated that an experienced crew has assembled a kite in about 8 minutes.
On November 2nd, the first kite flying was attempted on a British Merchant Ship EMPIRE MOON. The vessel proceeded out of the harbor a few miles to obtain maneuvering room, and then swung into the wind of about 4 knots. The vessel was making about six or eight so the relative wind was about 10 to 12 knots. Attempt was made to fly the admiralty type kite carried by the vessel, but without success. The piano wire kite line was lead from a wire drum fitted on the gypsy head of a cargo winch, through lead sheaves and pipe to a flying off block fitted at the top of the mainmast.
The Sauls-Vangrow kite was then assembled by the crew. On launching the kite it turned over and flew upside down. It was hauled in and launched again, flying right side up. About 500 feet of wire was used, but due to the extremely light wind the kite flew well aft with a resultant low cable angle. The flight was very steady and on launching and haul in operations there was no diving or swooping.
Arrangements were made to fly the kite from a mine sweeper (Fort William J113) on November 3, 1942. The vessel proceeded to sea at 7:00 A.M. and all other test work cleared up by about noon time. The kite was then assembled aft under very unfavorable conditions. There was insufficient deck space to accommodate the kite, and the end cells of the forward sections were assembled with the kite held in the air by the ship's crew.
There was about a 15 knot wind and the ship running at about 11 knots was swung to bring the wind over the starboard bow. The piano wire was led from a storage reel, over the gypsy head of the mine sweep winch, the through lead blocks, etc. to the flying off block on mainmast. This block was at about the approximate height of the bridge. The kite was launched from a point about 30 feet aft of the mainmast and immediately assumed heeled position in the air over the starboard quarter instead of the wind over the port quarter. About 100 ft. of line had been unreeled at the launching of the kite and for some reason no more was unreeled at this time. The kite cable angle to the horizontal was very slight, and the kite held steady in its heeled position. Gradually the kite heeled further, at the same time moving into the wind until it turned upside down, and climbed to a very steep cable angle. Apparently the kite was launched in very disturbed air which caused the heel and unusual direction of flight. However, it passed out of the disturbed air stream without diving into the upside down position.
About 1,000 ft. of cable was let out, the kite climbing steadily. When unreeling stopped, the average cable angle as determined by the sextant was over 50°. The ship was then swung to bring the kite over the beam. During this maneuver the kite held its steady flight. On further swinging the ship, bringing the kite cable forward of the beam, the kite lost the wind and started
to fall by swinging slowly side to side like a falling leaf. The kite cable hit the sea, relieving the kite of the motion imparted to it by the ship. The wind caught it and it picked up resuming normal flight, with cable still partially in the sea. The ship changed course again into the wind and the cable cleared the sea, resulting again in normal flight.
The kite was then hauled in and landed on the aft deck by means of a line attached to a small shackle running freely over the kite cable. In both the launching and landing operations there was no diving of the kite, it remaining practically on even keel at all times. The ship returned to the dockyard landing the party at about 5:30 P.M.
The piano wire was weighted and reported to be 21½#s per thousand feet. Its diameter by use of micrometer calipers was .073 inches. The specifications for kite cable set by the British Admiralty give weight 14 # per thousand feet .072" dia. and 1300 # ultimate strength. The difference in weight are still to be explained.
The advisability of running further tests was discussed with Lt. Com. Woodward during the morning of November 4th. There were no ships other than minesweepers available that day or next for the tests. It was felt that no further useful data would be obtained by flying the kites from such vessels. Arrangements were then made to take the kites and fly them from a cargo vessel which was to leave Halifax about Friday November 6th bound for Sidney, Cape Breton Island. In view of the tests already made it was not deemed necessary for the writer to make the trip to Sidney to witness the further tests.
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