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Manual of Fire-Loss Prevention

Description: Principles of fire-resistance classifications of building types and materials, general methods for controlling the spread of fire, and general fire-prevention measures.
Date: November 5, 1934
Partner: UNT Libraries Government Documents Department

Applied Methods and Equipment for Reducing Evaporation Losses of Petroleum and Gasoline

Description: From Scope of Report: "The subject matter in this bulletin is divided as follows: Theory of evaporation; methods of determining evaporation losses; lease operation; transportation and storage of crude petroleum; and evaporation losses of gasoline at the refineries."
Date: 1934
Creator: Schmidt, Ludwig
Partner: UNT Libraries Government Documents Department

United States Earthquakes, 1934

Description: Report discussing earthquake activity in the United States during 1934. The report is broken down by regions and has sections for specific earthquakes.
Date: 1934
Partner: UNT Libraries Government Documents Department

Aerodynamic Investigation of a Cup Anemometer

Description: Results of an investigation wherein the change of the normal force coefficient with Reynolds Number was obtained statically for a 15.5-centimeter hemispherical cup.
Date: July 1934
Creator: Hubbard, John D. & Brescoll, George P.
Partner: UNT Libraries Government Documents Department

Permissible Coal-Cutting Equipment Approved Prior to July 1, 1932

Description: From Schedules, Approvals, and Approval Plates: " This schedule has been revised from time to time to conform with information gained from testing a large variety of equipment and to bring the requirements in line with new developments in the art. As the approval plate on a machine evidences compliance with the safety requirements established by the Bureau the user, in fairness to the Bureau and the manufacturer, should not operate such a machine if it has been changed from the design approved without authority or if it has become unsafe through neglect or accident. The machine should be in proper condition, or the approval plate should be removed and destroyed."
Date: 1934
Creator: Ilsley, L. C.; Brunot, H. B. & Freeman, H. B.
Partner: UNT Libraries Government Documents Department

The Curry District, Alaska

Description: From abstract: The Curry district lies on the south flank of the Alaska Range, on the southeast side of Mount McKinley. Most of it is west of the Alaska Railroad. The eastern portion can be easily reached from several points along the railroad route, but the western portion is much more difficult of access, owing to the numerous glacial streams and the rugged topography. The relief of the area is great, the elevation ranging from 500 feet along the Chulitna River to 20,300 feet at Mount McKinley. The Chulitna River, a tributary of the Susitna River, drains the larger part of the area described. It flows in a broad valley in the eastern part of the district, and here the maximum relief is about 3,000 feet. The western part of the district is very rugged, with numerous peaks over 6,000 feet in elevation which have sheer slopes and almost unscalable pinnacles. Winding down through this maze of rugged mountains are four major valley glaciers-Eldridge, Buckskin, Ruth, and Tokichitna-and many tributary and smaller glaciers. Practically the entire district, with the exception of the higher peaks and ridges, has been glaciated. Timber grows along the main streams and extends to an elevation of 2,000 feet, but a large portion of the district lies above that elevation.
Date: 1934
Creator: Tuck, Ralph
Partner: UNT Libraries Government Documents Department

Core Drilling for Coal in the Moose Creek Area, Alaska

Description: From abstract: The Moose Creek area is in the western part of the Matanuska Valley, in south-central Alaska, about 165 miles by railroad north of the coast at Seward. Coal deposits in the valley have been known since the early 1890's, and there have been producing mines since 1916, but the annual production is only about 40,000 tons, or less than one-third of the total amount consumed in the Territory. Early in 1931 Congress authorized the investigation of mineral resources in areas tributary to the Alaska Railroad, which is Government owned and operated, for the purpose of stimulating development and hence increasing the traffic and revenue of the railroad. The technical work of carrying on these studies was entrusted by Col. O. F. Ohlson, general manager of the railroad, to the United States Geological Survey. One of the investigations undertaken was that of the Moose Creek area, where small coal mines are in operation. Difficulties have been encountered in these mines, owing to the faulted character of the formation, which causes unproductive work in mining and also produces a large percentage of fine coal, which is unsuitable for sale in distant markets. Field examination indicated that more favorable mining conditions might be found somewhat farther west. Core drilling was therefore done in 1932, in order to learn if workable beds of coal were present that might he mined at less cost and produce a better product than the present mines for competitive sale in markets of the Pacific coast.
Date: 1934
Creator: Waring, Gerald A.
Partner: UNT Libraries Government Documents Department

Notes on the Geology of the Alaska Peninsula and the Aleutian Islands

Description: Abstract: During the spring of 1932 an opportunity was offered by the United States Navy for a geologist to accompany an expedition organized to make a reconnaissance of the western part of Alaska Peninsula and the Aleutian Islands. This expedition visited several localities the geology of which was little known. It was found, as had already been expected, that the islands west of Unimak Pass are composed mainly of basic volcanic lavas and fragmental materials, into which have later been injected dikes, sills, and considerable masses of intrusive rocks, some of which are of acidic types and of granitic texture. These westward islands are bordered both to the north and south by depressions 2,000 fathoms or more in depth, and the islands have apparently been built up from that depth by the ejection and extrusion of volcanic materials since early Tertiary time. No rocks of proved pre-Tertiary age were seen, and the only sedimentary materials present may well have been derived from the erosion of the volcanic islands after they were built up above sea level. On the Alaska Peninsula pre-Tertiary sediments through which the volcanic materials broke to the surface are abundantly present. There is evidence that all the larger islands and the higher portions of the peninsula were severely glaciated during Pleistocene time. Each of the larger islands was the center of ice accumulation and dispersal, and the present topography, except upon recently active volcanic cones, shows strongly the effects of glacial sculpture.
Date: 1934
Creator: Capps, Stephen R.
Partner: UNT Libraries Government Documents Department

Some Lode Deposits in the Northwestern Part of the Boise Basin, Idaho

Description: From abstract: The report is limited to the geology of lode deposits in the northwestern part of the Boise Basin which are in or near mines that were in operation at the time of visit, in 1930. Owing to the recent inactivity of the formerly rich placer (leposits, there is nothing essential regarding them to add to Lindgren's report published in 1898. The area studied is underlain by granitic rock of the Idaho batholith, which is cut by dikes of Miocene(?) age. These dikes are dacite porphyry (intruded early) ; rhyolite porphyry, granophyre porphyry, and granite porphyry (closely related in character and age) ; and several basic varieties (of which some, at least, are of relatively late origin). Diorite porphyry dikes, of undetermined age but probably older than all of those named above, are also present.
Date: 1934
Creator: Ross, Clyde P.
Partner: UNT Libraries Government Documents Department

The Aachen wind-tunnel balance

Description: Report discussing a description of the balance in the Aachen wind-tunnel.
Date: November 1934
Creator: Wieselsberger, C
Partner: UNT Libraries Government Documents Department

The calculated effect of trailing-edge flaps on the take-off of flying boats

Description: The results of take-off calculations are given for an application of simple trailing-edge flaps to two hypothetical flying boats, one having medium wing and power loading and consequently considerable excess of thrust over total resistance during the take-off run, the other having high wing and power loading and a very low excess thrust. For these seaplanes the effect of downward flap settings was: (1) to increase the total resistance below the stalling speed, (2) to decrease the get-away speed, (3) to improve the take-off performance of the seaplane having considerable excess thrust, and (4) to hinder the take-off of the seaplane having low excess thrust. It is indicated that flaps would allow a decrease in the high angles of wing setting necessary with most seaplanes, provided that the excess thrust is not too low.
Date: November 1, 1934
Creator: Parkinson, J E & Bell, J W
Partner: UNT Libraries Government Documents Department

A method of calculating the performance of controllable propellers with sample computations

Description: This paper contains a series of calculations showing how the performance of controllable propellers may be derived from data on fixed-pitch propellers given in N.A.C.A. Technical Report No. 350, or from similar data. Sample calculations are given which compare the performance of airplanes with fixed-pitch and with controllable propellers. The gain in performance with controllable propellers is shown to be largely due to the increased power available, rather than to an increase in efficiency. Controllable propellers are of particular advantage when used with geared and with supercharged engines. A controllable propeller reduces the take-off run, increases the rate of climb and the ceiling, but does not increase the high speed, except when operating above the design altitude of the previously used fixed-pitch propeller or when that propeller was designed for other than high speed.
Date: January 1, 1934
Creator: Hartman, Edwin P.
Partner: UNT Libraries Government Documents Department

A complete tank test of a flying-boat hull with a pointed step -N.A.C.A. Model No. 22

Description: The results of a complete tank test of a model of a flying-boat hull of unconventional form, having a deep pointed step, are presented in this note. The advantage of the pointed-step type over the usual forms of flying-boat hulls with respect to resistance at high speeds is pointed out. A take-off example using the data from these tests is worked out, and the results are compared with those of an example in which the test data for a hull of the type in general use in the United States are applied to a flying boat having the same design specifications. A definite saving in take-off run is shown by the pointed-step type.
Date: February 1, 1934
Creator: Shoemaker, James M
Partner: UNT Libraries Government Documents Department

A complete tank test of the hull of the Sikorsky S-40 flying boat - American Clipper Class

Description: The results of a complete test in the N.A.C.A. tank on a model of the hull of Sikorsky S-40 flying boat ('American Clipper') are reported. The test data are given in tables and curves. From these data non-dimensional coefficients are derived for use in take-off calculations and the take-off time and run for the S-40 are computed. The computed take-off time was obtained by the Sikorsky Aviation Corporation in performance tests of the actual craft.
Date: December 1, 1934
Creator: Dawson, John R
Partner: UNT Libraries Government Documents Department

The effects of equal-pressure fixed slots on the characteristics of a Clark Y Airfoil

Description: A type of fixed open slot so arranged that no flow would pass through it at a lift coefficient corresponding to high-speed flight was investigated in the N.A.C.A. 7 by 10 foot wind tunnel to determine the possibilities of such a high-lift device for increasing the speed-range ratio of a wing. The condition of no through flow was achieved by locating the slot openings at points of equal static pressure at the design lift coefficient as determined from the pressure distribution about the plain wing. Two models of Clark Y wings with such equal-pressure slots were tested and the smoke-flow patterns about them observed. The results of this investigation show that the condition of no air flow through the slot at the desired lift coefficient is attainable. The surface discontinuities produced by the slot openings have, however, such a large effect on the drag that such slots show little promise. An appreciable increase is produced in the maximum lift and the speed-range can be as high as for the plain wing.
Date: October 1, 1934
Creator: Harris, Thomas A & Sherman, Albert
Partner: UNT Libraries Government Documents Department

Effect of retractable-spoiler location on rolling- and yawing-moment coefficients

Description: In this report are presented the results of wind-tunnel tests of retractable spoilers on the upper surface of a Clark Y wing, which have been made as part of an investigation of lateral control devices being conducted by the National Advisory Committee for Aeronautics. Spoilers with chords up to 15.0 percent of the wing chord were tested in several locations on a plain rectangular wing and in two locations on the same wing equipped with a 20.0 percent chord split flap down 60 degrees. Charts are given for four representative angles of attack from which values of rolling- and yawing-moment coefficients may be obtained for spoilers up to 15.0 percent chord located on the upper surface of a Clark Y wing. The tests showed that at low angles of attack practically the same rolling moments can be obtained with a given spoiler at any location back of 30.0 percent of the wing chord, while at high angles of attack there is a definite advantage in locating the spoiler at least as far forward as 30.0 percent of the chord. The yawing moments accompanying a given rolling moment increase positively as the spoiler location is moved forward from the trailing edge of the wing. It is concluded that the 30.0 percent chord location is probably the optimum provided that instantaneous response of the airplane to a control movement can be obtained.
Date: July 1, 1934
Creator: Shortal, J A
Partner: UNT Libraries Government Documents Department

Complete tank tests of two flying-boat hulls with pointed steps - N.A.C.A. Models 22-A and 35

Description: This note presents the results of complete tank test of N.A.C.A. Models 22-A and 35, two flying-boat hulls of the deep pointed-step type with low dead rise. Model 22-A is a form derived by modification of Model 22, the test results of which are given in N.A.C.A. Technical Note No. 488. Model 35 is a form of the same type but has a higher length-beam ratio than either Model 22 or 22-A. Take-off examples are worked out using data from these tests and a previous test of a conventional model applied to an arbitrary set of design specifications for a 15,000-pound flying boat. The comparison of these examples shows both pointed-step models to be superior to the conventional form, and Model 35 to be the better of the two. Model 35 is applied to a hypothetical 100,000-pound flying boat of the twin-hull type and performance calculations are made both for take-off and range. The results indicate that the high performance of this type of hull will enable the designer to use higher wing and power loadings than are found in current practice, with a resulting increase in range and pay load.
Date: September 1, 1934
Creator: Shoemaker, James M & Bell, Joe W
Partner: UNT Libraries Government Documents Department

The wave suppressor used in the N.A.C.A. tank

Description: So long a time was required for the disturbed water to become quiet after a model had been towed down the N.A.C.A. tank, that only 12 to 18 runs a day could be made. In order to shorten the time lost in waiting between runs, several different methods of suppressing the waves were tried. The most effective form of wave suppressor developed consists of wooden frames covered with fine copper screening and secured horizontally just beneath the surface of the water at the sides of the tank. With these suppressor placed every 50 feet along the length of the tank, 40 to 60 test runs a day can be made.
Date: December 1, 1934
Creator: Truscott, Starr
Partner: UNT Libraries Government Documents Department

Tank tests of a family of flying-boat hulls

Description: This report presents towing tests made in the N.A.C.A. tank of a parent form and five variations of a flying-boat hull. The beams of two of the derived forms were made the same as that of the parent and the lengths changed by increasing and decreasing the spacing of stations. The lengths of the two others of the derived forms were made the same as that of the parent while the beams were changed by increasing and decreasing the spacing of buttocks, all other widths being changed in proportion. The remaining derived form has the same length and beam as the parent, but the lines of the forebody were altered to give a planing bottom with no longitudinal curvature forward of the step. The test data were analyzed to determine the minimum resistance and the angle at which it occurs for all speeds and loads. The results of this analysis are given in the form of non dimensional curves for each model. The effect of variation in over-all size, as indicated by a "complete" test on any given hull, is pointed out. The effect of changing length alone by the spacing of buttocks, as well as the effects of the changes in length-beam ratio and longitudinal curvature that result from these operations are discussed. The difficulties encountered in interpreting test results of systematic families derived by the method used are emphasized. Further studies are suggested in which changes in the variable under consideration would not be obscured by secondary changes in other important variables.
Date: February 1, 1934
Creator: Shoemaker, James M & Parkinson, John B
Partner: UNT Libraries Government Documents Department

Tank tests of flat and v-bottom planning surfaces

Description: Four planing surfaces, all having beams of 16 inches and lengths of 60 inches but varying in dead rise by 10 degrees increments from 0 degrees to 30 degrees, were tested in the N.A.C.A. tank. The results cover a wide range of speed, loads, and trim angles, and are applicable to a variety of problems encountered in the design of seaplanes. The data are analyzed to determine the characteristics of each surface at the trim angle giving minimum resistance for all the speed and loads tested. A planing coefficient intended to facilitate the application of the results to design work is developed and curves of resistance, wetted length, and center of pressure are plotted against this coefficient. Several examples, showing the application of the test data to specific design problems are included.
Date: November 1, 1934
Creator: Shoemaker, James M
Partner: UNT Libraries Government Documents Department

Full-scale drag tests of landing lamps

Description: Drag tests were conducted in the N.A.C.A. full-scale wind tunnel on full-scale models of two Army Air Corps type A-6 landing lamps mounted on an 8 by 48 foot airfoil. Drag measurements were made with the lamps in the leading edge and attached to the lower surface at the 5 and 10 percent chord positions. The drag of the lamps when faired into the airfoil was also measured. The results show that at 100 miles per hour and at the angle of minimum drag of the airfoil the unaired lamps in the leading edge produced an increase in drag of 5.5 pounds and that the unaired lamps on the lower surface at either position increased the airfoil drag 22.5 pounds. These increases represent 6 and 24 percent of the minimum drag of the airfoil, respectively. Fairing the lamps into the airfoil reduced the drag of the lamps about 50 percent for the leading-edge position and about 60 percent for the two lower surface positions.
Date: May 1, 1934
Creator: Dearborn, C H
Partner: UNT Libraries Government Documents Department

Landing characteristics of an autogiro

Description: An investigation to determine the rate of descent, the horizontal velocity, and the attitude at contact of an autogiro in landings was made by the National Advisory Committee for Aeronautics at the request of the Bureau of Air Commerce, Department of Commerce. The investigation covered various types of landings. The results of the investigation disclosed that the maximum rate of descent at contact with the ground (10.6 feet per second) was less than the minimum rate of descent attainable in a steady glide (15.8 feet per second); that the rates of descent at contact were of the same order of magnitude as those experienced by conventional airplanes in landings; that flared landings resulted in very low horizontal velocities at contact. Also that unexpectedly high lift and drag force coefficients were developed in the latter stages of the flared landings.
Date: November 1, 1934
Creator: Peck, William C.
Partner: UNT Libraries Government Documents Department