The last 200 feet - A low-cost approach to landing aircraft in zero-zero conditions

Current Federal Aviation Administration Category I Instrument Landing System approach minima are a 200-foot above ground level Decision Height and 2,400-foot Runway Visual Range. The pilot may not commence an approach if the reported conditions are below these minimums and may only continue an approach below the decision height if the runway environment is in sight. This presentation will show that technology exists today to allow a pilot to continue his approach below published decision height to touchdown without ever actually `seeing' the runway environment outside of his cockpit. Onboard the aircraft, Global Positioning System enhanced by Wide Area Augmentation System typically provides instantaneous positional accuracy of less than one meter horizontally and 1.3 meters vertically. With this metric even the smallest aircraft could determine its location in X, Y, and Z to well within a fraction of its own footprint. Using high-precision GPS surveying equipment to perform a real-time kinematic survey, airport runway locations can be determined with centimeter level accuracy, making it conceivable to land an aircraft on a specific point on the runway to a very high degree of accuracy. Instrument flight with no outside visual cues imparts high levels of stress on the pilot. Landing an aircraft in zero-zero conditions would add significantly more stress. Synthetic Vision Systems that offer the pilot a high-fidelity representation of the outside world would lessen or preclude this stress. Many major universities, government agencies, and aerospace corporations are already at work to provide these type systems. SVS will most likely be initially designed for commercial, military, and business-class aircraft, and will cost tens to hundreds of thousands of dollars. This valuable and life-saving technology will not be affordable to most general aviation pilots. This paper proposes a reduced-cost SVS system for general aviation, based on a Microsoft Windows^TM-based tablet computer. This presentation will document the testing of this system under Visual Flight Rules conditions in order to quantify the achievable accuracy and characterize feasibility of the concept.