Showing papers on "Required navigation performance published in 1996"

Operational considerations in improving access to Juneau, Alaska

Abstract: While new technology resulting in improved navigation accuracy and integrity provides the potential for shorter and more efficient departure and arrival routes and lower minima, there are a great many corollary considerations that are necessary to make revised operations safe and efficient. At Juneau, given conventional navigation capability, the terrain allows only one route into and out of the airport. However, the integration of the multisensor navigation of the Smiths Industries FMS with GPS position sensing and RNP navigation and alerting capability created the potential for using the narrow Gastineau Channel as a sea-level departure and arrival route. This paper presents an overview of the procedure design and focuses on the operational cockpit integration aspects of how the procedures are to be flown. Details of the equipment and external factors that determine procedure availability are presented along with crew training requirements. Methods for safe extraction of the aircraft in the event of equipment failure are explained, and their evaluation during the demonstration flights is presented.

APALS program status: preproduction flight test results and production implementation

Abstract: The APALS system is a precision approach and landing system designed to enable low visibility landings at many more airports than now possible. Engineering development of the APALS system began October 1992 culminating in the pre- production Advanced Development Model (ADM) system currently undergoing flight testing. The paper focuses on the Cat III accuracy and integrity requirements defined by ICAO, Annex 10 and the required navigation performance (RNP) tunnel concept. The resulting ADM architecture developed to meet them is described. The primary measurement is made with the aircraft's weather radar and provides range and range rate information to the ADM necessary to update the precision navigation state vector. The system uses stored terrain map data as references for map matching with synthetic aperture radar with synthetic aperture radar maps. A description of the pre-production flight test program is included. Testing is being conducted at six different airports around the country demonstrating system performance in various environmental conditions (precipitation, heavy foliage, sparse terrain, over water and turbulence). ADM flight test results of 131 successful CAT II hand-flown approaches at ALbuquerque, NM and Richmond, VA are presented. Detailed statistical analysis of these results indicate that the APALS system meets the RNP for Cat III.

Continuity improvements via inertial augmentation of GPS-based landing system

Abstract: The role of inertial backup of GPS-based landing systems in the improvement of continuity is investigated. The purpose is to understand the relationship between the grade of inertial system and the system accuracy during various GPS discontinuity scenarios. GPS outages are considered at various locations on the approach. For systems that included pseudolites (PLs), outages are considered before entering the PL range of coverage (the "bubble") and after exiting the bubble. The inertial systems are assumed to be calibrated by GPS during the enroute portion of flight. Linear covariance analysis and Monte Carlo techniques are used to determine the navigation accuracy at the runway threshold to determine whether the system meets the various levels of Required Navigation Performance (RNP). It was found that in the event of a total loss of satellite GPS signals prior to bubble entrance, a navigation grade INS could be calibrated by 3 suitably placed PLs sufficiently accurately to provide an RNP that allowed the most stringent landing minimums (Category III). Other less drastic outage scenarios all indicated that substantial improvements in continuity can be achieved with inertial system augmentation. Except for GPS outages within 50 seconds of touchdown, navigation grade inertial systems were required for useful improvements. Conditions that allow tactical missile grade inertial systems for CAT III RNP for the case of a GPS outage within 50 seconds from touchdown are specified.

APALS Program Status and Pre-Production Flight Test Results

Abstract: The APALST” system is a precision approach and landing system designed to enable low visibility landings at many more airports than is now possible. Engineering development of the APALS”” system began in October d 1992 culminating in the pre-production Advanced Development Model (ADM) system currentl~,,undergoing flight testing. An overview of the APALS system is presented. The paper focuses on the Cat III accuracy and integrity requirements as defined by ICAO, Annex 10 [I] and the Required Navigation Performance (RNP) Tunnel Concept [2]. The resulting ADM architecture developed to meet them is described. The primary measurement is made with the aircratYs weather radar and provides range and range rate information to the ADM necessary to update the precision navigation state vector. The system makes use of stored terrain map data as references for map matching with Synthetic Aperture Radar (SAR) maps. A description of the Pre-Production flight test program is included. Testing is being conducted at six different airports around the country to demonstrate system performance in various environmental conditions (precipitation, heavy foliage, sparse terrain, over water and turbulence). ADM flight test results of 6 1 successful CAT II hand- flown approaches at Albuquerque, New Mexico ate presented. Detailed statistical analysis of these results indicate that the APALST” system meets the RNP for Cat Ill.

APALS Program Status, Pre-Production Flight Test Results and Production Implementation

Abstract: The APALS* system is a precision approach and landing system designed to enable low visibility landings at many more airports than now possible. Engineering development of the APALSTM system began October 1992 culminating in the pre-production Advanced Development Model (ADM) system currently undergoing flight testing. The paper focuses on the Cat III accuracy and integrity requirements defined by ICAO, Annex 10 [l] and the Required Navigation Performance (RNP) Tunnel Concept [2]. The resulting ADM architecture developed to meet them is described. The primary measurement is made with the aircraft’s weather radar and provides range and range rate information to the ADM necessary to update the precision navigation state vector. The system uses stored terrain map data as references for map matching with Synthetic Aperture Radar (SAR) maps. A description of the Pre-Production flight test program is included. Testing is being conducted at six different airports around the country demonstrating system performance in various environmental conditions (precipitation, heavy foliage, sparse terrain, over water and turbulence). ADM flight test results of 131 successful CAT II hand-flown approaches at Albuquerque, NM and Richmond, VA are presented. Detailed statistical analysis of these results indicate that the APALSTM system meets the RNP for Cat III.