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September 15, 1924 AVIATION 989 John L. Mitchell Trophy In memory of his brother who was killed during the World War, Brig. Gen. Wm. Mitchell placed The John L. Mitchell Trophy in competition at Detroit in 1922, a race for pilots of the first pursuit group flying standard pursuit type ships. This contest will be watched with interest by the public, for they will have an opportunity of witnessing the skill of these highly trained pursuit pilots, this race will be run in exactly the same manner as the Pulitzer high speed contest. It will be for a distance of 200 km. (124.27 mi.) and will consist of four laps of a 50 km. course. Planes will be sent away from a flying start and this event is scheduled to start at 1 p. m., Saturday, Oct 4. The Pulitzer Trophy Event No. 12 is the premiere event of this great aeronautical gathering of 1924, and will be for the Pulitzer trophy. This race is too well known to need discussion. It may be simply said that that it is a contest for high speed planes showing a maximum ground speed of greater than 175 mi./hr. This race carries with it a condition which has done more to bring forward the finest design for airplanes of this type than has any similar contest in the world. This provision is that all planes entered must have a theoretical stalling speed not exceeding 75 mi./hr. It is further provided that they shall have a factor of safety for the wings as follows: Wings 7 1/2 High incidence conditions with center of pressure at its most forward position. 5 Low incidence condition with center of pressure at location corresponding to maximum ground speed. 4 Reverse load condition. Fuselage 7 Flying and landing loads The strength values for wood as given by the Forest Products Laboratory for 10 per cent moisture content and the Army method of stress analysis shall be used in making all strength calculations. Further interesting provisions of the contest will be noted. Sufficient tankage must be provided for the Pulitzer route plus 33 1/3 per cent. This shall be based upon engine consumption determined from approved dynamometer test and estimated length of time required to complete the race. The decision of the Contest Committee shall be final. Each entry must be accompanied by a properly drawn and certified statement giving the fuel consumption of the engine at the maximum r.p.m. to be used in the race. All planes entered in this race must be so designed with proper exhaust manifolds, shields, deflectors, ventilators, or other design characteristics, which, in the opinion of the Contest Committee will prevent exhaust gases from reaching the pilot during flight. Any plane not so equipped or designed will be subject to disqualification. Each plane in this race must leave the ground under its own power only, must not discard any part of its equipment in flight, and must have proper landing equipment attached at all times. The machine completely loaded with pilot, at 180 lb., and fuel and water sufficient for the race, must be weighed by the contest committee not later than three days prior to the date of the race, and this weight shall be checked against the technical data submitted for determining the stalling speed. This speed shall be calculated by the following formula: Stalling speed in mi./hr. = [[symbol - square root]] Weight of airplane in lb. [[/symbol - square root]] / Wing area in sq. ft. x Ky max. The total wing area shall be taken as the projected area of the freely exposed main surfaces from root to wing tip on the plane of the X and Y axes of the airplane. The thrust line may be considered as the X axis. Axle fairings, if of a lifting section, may be include as wing area. Characteristic curve must show the maximum Ky given by a test of a rectangular wing model of the airfoil section or sections used, 3 in. by 18 in. in size. In the case of tapered wings, wings with wash0in or wash-out built into the wings, or arrangement other than a straight airfoil, the model shall be geometrically similar to the actual wing used and have an area of approximately 54 sq. in. The stalling speed shall be calculated from the maximum Ky obtained on the model. No corrections such as speed scale, aspect ratio, biplane, stagger, etc., will be allowed. In view of the possibility of widely varying results which may be obtained by using the results of tests obtained in different wind tunnels, it is stipulated that all wing models must be tested under uniform conditions at a speed of 40 mi./hr. in the same wind tunnel, which in this case is the tunnel at the Massachusetts Institute of Technology, at Boston. In order not to penalize airplanes which may exceed this stalling speed slightly by having them completely barred from this contest, a further stipulation is made in the regulations. If, after the airplane has been weighed in accordance with these regulations, and checked against the model characteristics submitted, the theoretical stalling speed shall be found in excess of 75 mi./hr., the airplane will be penalized in the race at that rate of 4 mi./hr. The permitted theoretical stalling speed of 75 mi./hr. shall not be exceeded by more than 3 per cent without total disqualification. Foreign Contestants Doubtful It had been hoped that foreign contestants would be entered in the 1924 Pulitzer. While no definite word has been received from abroad it appears doubtful if entries can now be expected. Furthermore, recent flights of some of the latest high speed planes abroad, have brought out the fact that our friends across the sea must advance considerable in the construction of this type of plane before they can expect to come to this country and take the trophy from us. Very little attention has been paid over-seas to the landing speed of this type of plane. It has largely depended upon the skill of the pilot and how much of a chance he is willing to take in landing. From the unofficial information at hand it would appear that one of the latest foreign high speed planes, which has just recaptured a new world's record or two, has a theoretical landing speed of considerably in excess in 100 mi./hr. We have no development if we are simply to base our designs upon the courage of the pilot and add a few miles to the landing speed, and thereby increase the high speed. In this country, by placing restrictions on this contest we are accomplishing results. Our high speed planes are without equal in the world. We have learned lessons which will be of immeasurable benefit to us in case of war. The development of these high speed planes, while criticized to some extent, will make it possible for this country to put in the air pursuit type airplanes which have not their equal in the world. We cannot overlook the actual necessity of conducting races of this kind. It has often been said that competition is the life of trade. Lessons are no more clearly learned than when our designers and pilots are stressing their ingenuity and skill to the utmost in designing, building and flying airplanes which will give the maximum performance under trying conditions. It is to be regretted that new ships could not be constructed for this years premiere event, but we will have an opportunity to see the application to some extent of the lessons which we learned last year. Predictions of what speed will be made are matters of guess. Had new planes been developed at the same rate that they have developed for the past four years we would be safe in predicting that this year's Pulitzer race would be won at a speed of 260 mi./hr. On this same basis the writer predicted a speed of 244.5 mi./hr. for the 1923 event which was actually won at an average speed 243.68 mi./hr. American Air Committee in Paris The Paris Post No. 1 of the American Legion, with headquarters in Paris, France, recently appointed an Aviation Committee for the purpose of developing Franco-American air relations. The Committee is composed of the following: R. C. Wood, chairman; Maj. Charles D. Westcott and William Goodell.
