The results of a forty-minute exposure of the HM.2 Hoverferry are presented. Quantitative evaluations were made from aft seats on the starboard side for a sea state considered calm and visually estimated at one-half to one foot. Since this type of craft is sensitive to sea state, the conclusions are based on ideal conditions. Some drawings are included.
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT DESIGN, AIRCRAFT PERFORMANCE, HOVERCRAFT GROUND...
A two dimensional model for the chordwise flow near the wing tip of the tilt rotor in hover is presented. The airfoil is represented by vortex panels and the rotor is modeled by doublet panels. The rotor slipstream and the airfoil wake are simulated by free point vortices. Calculations on a 20 percent thick elliptical airfoil under a uniform rotor inflow are performed. Variations on rotor size, spacing between the rotor and the airfoil, ground effect, and the influence upper surface blowing in...
Topics: NASA Technical Reports Server (NTRS), AIRFOIL PROFILES, GROUND EFFECT (AERODYNAMICS), HOVERCRAFT...
Interactions between the rotors and wing of a rotary wing aircraft in hover have a significant detrimental effect on its payload performance. The reduction of payload results from the wake of lifting rotors impinging on the wing, which is at 90 deg angle of attack in hover. This vertical drag, often referred as download, can be as large as 15 percent of the total rotor thrust in hover. The rotor wake is a three-dimensional, unsteady flow with concentrated tip vortices. With the rotor tip...
Topics: NASA Technical Reports Server (NTRS), AIRFOILS, COMPUTATIONAL GRIDS, DRAG, HOVERCRAFT GROUND EFFECT...
