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  • Author or Editor: Alfred R. Rodi x
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Alfred R. Rodi, James C. Fankhauser, and Robin L. Vaughan

Abstract

Aircraft distance-measuring-equipment (DME) data are used to update position, velocity, and wind measurements from inertial navigation systems (INS) measurements. Data from conventional single-channel DME sets, suitably calibrated, are shown to be adequate to resolve the Schuler oscillation and correct INS positions to better than 1-km accuracy. The satellite-based NAVSTAR global position system (GPS) is rapidly superseding other systems for external position reference. However, DME is reliable and very accurate and has been recorded on many research datasets. The principal limitation of the DME is that it is restricted to land-based navigation. The regression technique used does not necessitate multiple DME receivers or station switching and involves few restrictions on the collection of the data. However, the results improve when more than one station is used. Comparisons with other navigation systems (interferometer and loran) demonstrate the method's skill in resolving INS errors. Intercomparisons among several research aircraft flying in close formation support the method's usefulness in correcting biases in INS data.

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James W. Wilson, James A. Moore, G. Brant Foote, Brooks Martner, Alfred R. Rodi, Taneil Uttal, and James M. Wilczak

The Convection Initiation and Downburst Experiment (CINDE) was conducted in the Denver, Colorado area from 22 June to 7 August 1987 to study processes leading to the formation of deep convection and the physics of downbursts. A total of 6 Doppler radars, 87 mesonet stations, 3 research aircraft, 8 sounding systems and numerous photographic facilities were deployed within an 85 km × 85 km area. A comprehensive data set was obtained including measurements of convergence lines, downbursts, and tornadoes that occurred on 35, 22, and 11 days, respectively.

This paper describes the objectives of the experiment and the specific facilities employed. Highlights and preliminary results are presented for several studies underway to show the type of data collected and to illustrate the sorts of analyses being pursued. Examples chosen include the topics of cloud initiation on stationary convergence lines, terrain-induced circulations, downbursts, tornadoes, and tracking chaff in precipitation-filled regions.

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