May 19, 2018, 16:23Scott A. Whittey
Source; American Institute of Aeronautics and Astronautics
Developing the Navy’s NC Flying Boats:
Transforming Aeronautical Engineering for the First
Eric J. Silberg and David J. Haas
Naval Surface Warfare Center, Carderock Division, West Bethesda, Maryland, 20817
Significant advances in construction were necessary in order to build the unprecedented Nancy flying boats.
The aircraft was simply too large and complex to be built by a single manufacturer, especially
given that the original intent was to produce the aircraft in quantity for combat use. It was decided to break the construction up into components and sub-contract the build to manufacturers who could fabricate the specialized pieces. Curtiss would be responsible for the overall construction and integration of all the parts, and the Navy, with Westervelt as its representative, would retain overall authority over the build.
This method of construction, while standard today, and common for ships of the day was new for aircraft and required significant coordination and precision in design in order for all the pieces to fit together and work as required. The following major components of the NC flying boats were built by the different companies
Shown in Table 1.
Manufacturers of NC Flying Boat Components
Hulls: Curtiss Engineering Corporation, Garden City, NY (NC-1)
Lawley & Sons Boat Co, Boston, MA (NC-2, NC-3)
Herreschoff Co., Briston, RI (NC-4)
Tail Booms: Pigeon -Fraser Hollow Spar Co., Boston, MA
Gas Tanks: Aluminum Co. of America, Pittsburg, PA
Wings, Control Surfaces, and Struts: Locke Body Co., New York City, NY ,Unger Bros., Newark, NJ
Metal Fittings: Brewster Body Co., New York City, NY, Beaver Machine Co., Newark, NJ
Wing Tip Floats: Albany Boat Co., Albany, NY
Liberty Engines: Packard Motor Company, Detroit, MI
24“NC Boats Were Built to Fight Submarines”. Aircraft Journal , May 24, 1919. Archive of the National Air and Space Museum, Washington, D.C., NC-4 Collection.
These companies had significant expertise, but in areas not necessarily related to aircraft manufacturing. For example, Unger Brothers was a maker of fine silverware and jewelry,
Locke Body Company was a high -end automobile coach -builder, and Pigeon Fraser Hollow Spar Company built masts and spars for racing yachts.11 Westervelt, G. C., “Design and Construction of
NC Flying Boats”. United States Naval Institute Proceedings, Vol 45, No
199, September 1919, pp. 1529 -1581.
There was concern early in the process that the components would not fit or be serviceable, but those fears were quickly allayed during the first build of the NC-1. These companies were able to quickly adapt their specialties to the unique requirements of aircraft manufacturing and the assemblies all fit together very well
Equipped for Success
The vehicle itself was not the only development in aviation technology.
The equipment installed and used on the transatlantic flight was cutting edge, and some was being tested for the first time. The Nancies were equipped with a full assortment of avionics. The cockpit had airspeed gauges, altimeters, compasses, pitch attitude and angle of bank indicators, and engine performance and status gauges
. Up front in the navigator’s compartment, the aircraft commander had a specially designed sextant that
could be used without a horizon for sighting, a drift indicator compass, and a table under the deck for
all the necessary maps and charts. The real innovations were in the radio compartment, though. The
radio operator had access to 75 mile short range and 300 mile long range radio sets , and there was an intercom system allowing the crew to speak with one another and even allowed the commander to speak over the radio. There were two sets of antennae for use depending on whether the boat was
on the water or in the air; one fixed between the wing struts and one trailing unit that could be reeled in before landing (Fig. 24).
These radios allowed the Nancies to communicate with each other and with the ships strung out across the Atlantic .Radio was not used for communication alone; for the first time it would be used over a long distance for navigation. The Nancies had radio compasses, or radio direction finders, that the radio operator would tune to a transmitter to determine the aircraft’s relative bearing to the location of the transmitter . Ships strung out across the Atlantic were equipped with these transmitters to provide a beacon for the aircraft to follow.
The radio compass worked well while installed on the NC-2 with its twin -tandem engine configuration,
providing good bearings out to sixty miles. Unfortunately, there was insufficient time to fully test the installation with the final engine configuration and the interference created by the centerline engines significantly reducing the radio compass’ effective range.
26 Correspondence from CDR J. Towers, Commander NC Seaplane Division One, to Chief of Naval Operations, November 1919. Archive of the National Air and Space Museum, Washington, D.C., NC-4 Collection.
27 Smith, R. K., First Across! The U.S Navy’s Transatlantic Flight of 1919 . Naval Institute Press, Annapolis, MD,1973.
The compasses and gauges were self -illuminating for visibility at night, however these needed to be “recharged” regularly by flashlight. Powering all this equipment were batteries and a wind-powered generator located in the slipstream of the centerline propellers. The result was a better equipped aircraft than had ever before flown, and it needed to be, in order to find its way across the ocean.https://screenshots.firefox.co.../www.navsea.navy.mil https://screenshots.firefox.co...V20/books.google.com
U. S. NAVAL INSTITUTE, ANNAPOLIS, MD.
DESIGN AND CONSTRUCTION OF THE NC
By Commander G. C. Westervelt, C. C, U. S. Navy
In June, 1917, two months after the entry of the United States
into the World War, no definite air policy or program had been
adopted by this country. This condition was due to the lack of
any conclusive information regarding the work of the Allied
Governments along these lines, and to varied and contradictory
recommendations which had been received from the War De-
partments and the Admiralties of Great Britain and France as
to the types of planes which should be adopted by this country. To
remedy this condition an informal joint Army and Navy Board
was appointed to proceed to Europe and to make a study of air
matters among the principal governments engaged in the war
against Germany, and to recommend the steps to be taken by our
government in building up its own air services and in carrying
out a definite air policy.
The personnel of this committee was Major R. C. Boiling,
Captain V. C. Clark, Captain E. S. Gofrell, Captain Howard
Marmon and Captain Hughes representing the army, and Lieu-
tenant W. G. Child and the writer representing the navy. In
accordance with instructions to the committee, they proceeded
to Europe, arriving in London the latter part of June. At this
time, the naval activities of the U. S. Government were directed
mainly against the submarines. The center of naval activities
was the American Embassy in London, and by this time the naval
officers had become keenly aware of the grave menace of the
German submarines. At the embassy all discussions centered
around this subject, and it was evident that fuller methods of
combating the submarine must be provided and provided very
quickly. Accordingly, we began a particular and detailed study
of the types of aircraft for use against the submarine menace.
This study was carried on in England, in France, and in Italy,
and, as a result of this study, it was concluded that the quickest
way for the navy to obtain results in the air would be with kite
balloons, for observation purposes, anchored to a destroyer or
some other type of patrol vessel, and with seaplanes of the flying
boat type, as differentiated from the hydroaeroplane, for patrol
purposes and for the bombing of submarines.
1530 Design and Construction of " NC " Flying Boats
To facilitate construction, various parts were made under sub-
contracts from the Curtiss Company. The principal ones which
, may be noted are as follows. Wing panels, control surfaces,
and wing struts, were built by Locke & Company of New York
City, expert manufacturers of high-class motor car bodies. Metal
parts were made by Unger Brothers, Newark, N. J., manufacturers
of silverware, jewelry and all kinds of metal articles ordinarily
handled by jewelers. Later, to expedite the production of metal
parts, some of these were manufactured by the Beaver Machine
Works of Newark, and some by Brewster and Company of New
York City. Wing tip floats were built by the Albany Boat Company, builders of high-class steam launches and motor boats.
These, later were replaced by larger floats built by the Naval Air-
craft factory of Philadelphia. The outriggers supporting the tail
were built by the Pigeon-Fraser Hollow Spar Company of Boston,
makers of masts and spars for racing yachts. The gasoline tanks
were built by the Aluminum Company of America of Pittsburgh.
The construction of these tanks was the largest and most difficult
job of this nature ever undertaken by any aluminum manufacturer.
Two of the hulls to be supplied by the navy were built by Lawley
& Sons of Neponset, Mass., and one by the Herreschoff Manufacturing Company of Bristol, R. I. These hulls were built on the basis of cost, plus 10 per cent profit on an estimated cost, with the understanding, if the cost could be reduced below the estimated cost, the contractor would be paid 10 per cent on the estimated cost, and, in addition, 25 per cent of the difference
between the actual and the estimated costs.
To assist the Curtiss Company in expediting the production
of these parts, and to aid in every way in the construction and
assembly of the machine, four officers attached to the office of
the writer, were detailed to work with Mr. Gilmore of the Curtiss
Engineering Corporation, who had been placed in full charge of
the construction work on these four machines. Only because of
the faithful work of these officers was it possible to complete the
first of these flying boats in September, 1918.