Collection Efficiency and Ice Accretion Characteristics of Two Full Scale And One 1/4 Scale Business Jet Horizontal Tails
Collection efficiency and ice accretion calculations have been made for a series of business jet horizontal tail configurations using a three-dimensional panel code, an adaptive grid code, and the NASA Glenn LEWICE3D grid based ice accretion code. The horizontal tail models included two full scale wing tips and a 25% scale model. Flow solutions for the horizontal tails were generated using the PMARC panel code. Grids used in the ice accretion calculations were generated using the adaptive grid code ICEGRID. The LEWICE3D grid based ice accretion program was used to calculate impingement efficiency and ice shapes. Ice shapes typifying rime and mixed icing conditions were generated for a 30 minute hold condition. All calculations were performed on an SGI Octane computer. The results have been compared to experimental flow and impingement data.
A preliminary design for an affordable head-up display was developed under a NASA technology transfer contract. Attention was paid to the drivers that have here-to fore kept HUDs out of the general aviation fleet. These drivers are: high luminance (brightness), large physical size, wide field-of-view and the need for dedicated electronics. The HUD makes use of commercial off-the-shelf components and PC electronic microprocessors and operating systems. In the GA HUD, the optics were simplified using a single curved combiner providing both collimation and superposition. The lateral field-of-view will be approximately 15-18 degrees depending on the cockpit geometry. This optical arrangement leads directly to a much smaller physical size. The HUD is being developed primarily as a visual flight aid although the symbology will support limited instrument use, such as instrument approaches and recovery from unusual attitudes.