Author Description

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt:...engine usually are given a 10-hour test at 1,800 r. p. m. At this speed these propellers absorb about 265 horsepower. A power curve is usually taken on these propellers before the 10-hour run. Propellers for the 150-horsepower Hispano-Suiza engine are given a 10-hour test at 500 horsepower. At this horsepower, these propellers usually turn from 1,950 r. p. m. to 2,000 r. p. m., depending upon the design. An r. p. m. power curve is usually taken on these propellers before the 10-hour run. Propellers for the 300-horsepower Hispano-Suiza engine are usually given a 10-hour ran at 450 horsepower. At this input, these propellers turn about 1,950 r. p. m. An r. p. m. power curve is usually taken on these propellers before the 10-hour run. Propellers for the 400-horsepower Liberty engine and engines of higher horsepower are usually given a 10-hour test at 50 per cent power overload. An r. p. m. power curve is always taken on these propellers before the 10-hour run. Propellers built of a material which is not standard are usually given tests of much longer duration than those built of approved woods. These tests are usually of 30 hours' duration in order to determine whether the material will show fatigue. Propellers of unusual design, such as adjustable pitch propellers, etc., are given special tests in order to obtain design data. In any case in which the propeller is to be used on an airplane it is given an endurance run in line with those specified above. Whenever it seems advisable any propeller is run to a speed and horsepower input which destroys it. The maximum horsepower available is about 1,350. Propellers for the Liberty 12 engine have been run to this horsepower without any visible damage. Typical test data.--The following is typical of the data usually...