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Hovering and Transition Flight Tests of a 1/5-Scale Model of the Ryan X-13 VTOL Airplane
Report discussing an investigation of the dynamic stability and control characteristics of a model of the Ryan X-13 jet VTOL airplane in hovering and transition flight. Flight control was smooth and easy without the gyroscopic effects of the engine represented, but adding a simulation of the gyroscopic effects caused the plane to become uncontrollable in hovering flight without artificial stabilization. The transition was found to be easy to perform with and without gyroscopic effects, but the model had a tendency to fly in roll and slideslipped attitudes.
The Effects of Fuel Sloshing on the Lateral Stability of a Free-Flying Airplane Model
Memorandum presenting an investigation in the free-flight tunnel to determine the effect of the sloshing of fuel in partly filled, unbaffled tanks on the lateral stability of a free-flying model. Flight tests were made to determine the effects of the water sloshing for different depths of water and various masses and moments of inertia of the model. The sloshing caused small-amplitude, high-frequency lateral oscillations which were superimposed on the normal Dutch roll oscillation so that the lateral motions of the model appeared jerky.
Static Directional Stability of a Tandem-Helicopter Fuselage
Memorandum presenting an investigation to determine the static directional stability of a fuselage typical of tandem helicopters. The model consisted of a body with an elliptical cross section, a rear rotor pylon which was faired to form a large vertical tail with a very thick airfoil section, and a small horizontal tail mounted at about the midpoint of the height of the vertical tail. Results regarding the stability of the original model, the causes of low directional stability, and tests of some practical modifications of increasing directional stability are provided.
Low-Speed Wind-Tunnel Tests of a 1/8-Scale Model of the Bell D-188A VTOL Airplane
Report discussing the results of an investigation to determine the low-speed power-off stability and control characteristics of a model of the Bell D-188A VTOL airplane. The static stability and control characteristics were generally satisfactory except above certain angles of attack and aileron effectiveness dropped off as the angle of attack was increased. Modifications for increasing the directional stability by altering the vertical tails are also described.
Vertical Descent and Landing Tests of a 0.13-Scale Model of the Convair XFY-1 Vertically Rising Airplane in Still Air, TED No. NACA DE 368
"An investigation is being conducted to determine the dynamic stability and control characteristics of a 0.13-scale flying model of Convair XFY-1 vertically rising airplane. This paper presents the results of flight and force tests to determine the stability and control characteristics of the model in vertical descent and landings in still air. The tests indicated that landings, including vertical descent from altitudes representing up to 400 feet for the full-scale airplane and at rates of descent up to 15 or 20 feet per second (full scale), can be performed satisfactorily" (p. 1).
Additional Studies of the Stability and Controllability of an Unswept-Wing Vertically Rising Airplane Model in Hovering Flight Including Studies of Various Tethered Landing Techniques
Report discussing the results of an investigation to determine the stability and control characteristics of a flying model of an unswept-wing vertically rising airplane. Information about stabilization, maneuverability, rolling motions, and landings is provided.
Effect of the Proximity of the Ground on the Stability and Control Characteristics of a Vertically Rising Airplane Model in the Hovering Condition
Report discussing the effect of the proximity of the ground on the stability and control characteristics of a vertically rising airplane model in the hovering condition. The dynamic behavior of the model in take-offs and landings and when it was hovering near the ground was also investigated. Force tests to determine the change in the vertical-tail yawing moments with control deflection and with angle of yaw for various heights were also conducted.
Stability and Control Flight Tests of a 0.13-Scale Model of the Consolidated-Vultee XFY-1 Airplane in Take-Offs, Landings, and Hovering Flight: TED No. NACA DE 368
Report presenting an investigation to determine the dynamic stability and control characteristics of a scale flying model of the Consolidated-Vultee XFY-1 vertically rising airplane. It includes the results of flight tests to determine the stability and control characteristics of the model in hovering, take-offs, and landings.
Dynamic Stability and Control Characteristics of a Delta-Wing Vertically Rising Airplane Model in Take-Offs, Landings, and Hovering Flight
Report presenting an investigation by means of tests of a flying model in still air to determine the dynamic stability and control characteristics of a delta-wing vertically rising airplane in take-off, landing, and hovering phases of flight. The uncontrolled pitching motion consisted of an unstable oscillation which was more unstable with a rearward than with the normal center-of-gravity location.
Dynamic stability and control characteristics of a vertically rising airplane model in hovering flight
Report presenting an investigation to determine the stability and control characteristics of a vertically rising airplane model. Results of preliminary hovering flight tests are made in still air, away from the interference effects of the ground and side walls, and with normal airplane-type controls operating in the slipstream.
Take-Off and Landing Characteristics of a 0.13-Scale Model of the Convair XFY-1 Vertically Rising Airplane in Steady Winds, TED No. NACA DE 368
"An experimental investigation has been conducted to determine the stability and control characteristics of a 0.13-scale free-flight model of the Convair XFY-1 airplane during take-offs and landings in steady winds. The tests indicated that take-offs in headwinds up to at least 20 knots (full scale) will be fairly easy to perform although the airplane may be blown downstream as much as 3 spans before a trim condition can be established. The distance that the airplane will be blown down-stream can be reduced by restraining the upwind landing gear until the instant of take-off" (p. 1).
Flight Investigation of the Stability and Control Characteristics of a 0.13-Scale Model of the Convair XFY-1 Vertically Rising Airplane During Constant-Altitude Transitions, TED No. NACA DE 368
"An investigation is being conducted to determine the dynamic stability and control characteristics of a 0.13-scale flying model of the Convair XFY-1 vertically rising airplane. This paper presents the results of flight tests to determine the stability and control characteristics of the model during constant-altitude slow transitions from hovering to normal unstalled forward flight. The tests indicated that the airplane can be flown through the transition range fairly easily although some difficulty will probably encountered in controlling the yawing motions at angles of attack between about 60 and 40" (p. 1).
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