This standard defines the characteristics of WXR equipment intended for installation in commercial transport aircraft. The primary purpose is weather detection, ranging and analysis. Its secondary purpose is ground mapping to facilitate navigation by display of significant land contours.
This standard defines an airborne pulse Doppler weather radar system for weather detection and ranging. It expands the capabilities of the ARINC 708 system through the inclusion of forward looking windshear prediction.
A new concept in commercial airborne weather radars was developed for the turbo and pure jet-powered general-aviation aircraft. This radar presents a steady, nonfading weather or ground picture, without using the conventional direct-view storage tube, by utilizing digital processing techniques. ...Careful treatment of the radar design parameters allows 200 n. mile range operation while only requiring a few amperes of 28 V d-c from the aircraft power bus. ...These techniques are being applied to a family of radar systems.
A number of design parameters are traded off in the design of an airborne weather radar system. The inter-relative effects of design tradeoffs can be meaningfully approximated by application of the standard range equation which takes into account such items as peak transmitter power, width of the transmitted pulse, target area and reflectivity characteristics, transmitter wavelength, antenna gain, and the receiver overall noise figure. ...Selection of that radar system which is best suited to the particular aircraft to be equipped not only increases the utility of the aircraft, but also the safety of operation within given weather margins. ...Optimal allowances made for such installational limitations as reflector size, radome design, and temperature environments enhance both the performance and the reliability of the radar.
AN investigation of airborne radar of 5.5-cm wavelength to be used for weather mapping is discussed in this paper. Results show that radar of this wavelength paints an accurate picture of the weather, thus permitting the pilot to detour a storm area with a minimum increase in flight time or to navigate through a storm while avoiding areas of heaviest turbulence. ...Results show that radar of this wavelength paints an accurate picture of the weather, thus permitting the pilot to detour a storm area with a minimum increase in flight time or to navigate through a storm while avoiding areas of heaviest turbulence. ...In addition, this radar provides warning of hail shafts or tornadoes or of impending collision with terrain; its good terrain-mapping ability enables the pilot to scan an airport area to determine best possible flight paths.
The AN/APG-67 Multimode Radar is the newest tactical fighter radar that is being designed and developed explicitly for Northrop's F-20 Tigershark. ...Characteristics of the AN/APG-67 radar are described in terms of each of the four line replaceable units (LRUs): antenna, transmitter, radar target data processor, and radar data computer. Finally, data from the flight test program is presented for all of the major radar modes. ...In the air-to-air missions of supersonic intercept, combat air patrol, and air superiority, the radar modes include search and track for both look-up and look-down situations and automatic acquisition and track for air combat.
Radar Altimeters are being included in several existing Air Force aircraft. Of these, the A-10, F-15, and the F-16 are also envisioned to perform the night, under the weather attack mission. ...This mission, coupled with limited available cockpit space and the anticipated high pilot workload has led to a design effort to include the radar altimeter on the HUD. The LANTIRN system offered a key opportunity to accomplish this HUD integration. ...Plans are currently being made to conduct a simulation to make minor changes to the display based on test results to further optimize the display. This radar altimeter design and particularly the way the design has evolved should serve as examples for future efforts.
An airborne weather radar installation has been developed for light centerline thrust aircraft. A pod was developed and tested to attach to the underside of the wing and provide a location for a light weight antenna-receiver-transmitter unit.
A scanning optical radar system for meterological studies is briefly described. The techniques of obtaining efficient, high pulse repetition rates from a ruby laser, scanning the transmitter and receiver beams, and the operation of the B scope area display are discussed.
The 94 GHz MMW airborne radar system that provides a runway image in adverse weather conditions is now undergoing tests at Wright-Patterson Air Force Base (WPAFB). ...This system, which consists of a solid state FMCW transceiver, antenna and digital signal processor, has an update rate of 10 times per second, 0.35° azimuth resolution and up to 3.5 meter range resolution. The radar B scope (range versus azimuth) image, once converted to C scope (elevation versus azimuth), is compatible with the standard TV presentation and can be displayed on the Head Up Display (HUD) or Head Down Display (HDD) to aid the pilot during landing and takeoff in limited visibility conditions.
An analysis is made of the spectrum of refractivity fluctuations in regions of CAT and of its radar reflectivity as a function of wavelength. The results are compared to the minimum detectable reflectivity of airborne radars having optimum state of the art characteristics at each wavelength. ...The results are compared to the minimum detectable reflectivity of airborne radars having optimum state of the art characteristics at each wavelength. It is shown that the best radars now feasible can barely detect the most reflective CAT at 10 na. mi. ...It is shown that the best radars now feasible can barely detect the most reflective CAT at 10 na. mi. (i.e. 1 minute warning).
The AN/APG-67 Multimode Radar is a state-of-the-art coherent digital fire control radar developed for the Northrop F-20 Tigershark Aircraft. ...Each of these measures played a highly instrumental role in the successful development of the radar and as described in the paper, demonstrated the high payoff on investment that these activities provided.
A promising technique is to measure the radio refractive eddies and gradients by radar backscatter. Radio refractive index eddies can, in principle, be found where an atmosphere characterized by a nonadiabatic lapse rate of refractive index is stirred up by turbulence.
Phased planar array radars represent a class of equipment employing hundreds or thousands of individually steerable radiating and receiving elements. ...At the expense of some system availability, these policies require only part-time presence of maintenance personnel and may well be the most attractive alternatives for phased array radar systems possessing some degree of surplus performance.
Two sets of approaches to detect the presence of supercooled liquid water (SLW) over an airport area with radars are overviewed. The first set focuses on how scanning radars such as those existing in national networks might provide maps of icing likelihood and perhaps intensity over the approach area. ...The second set deals with the potential uses of dedicated low-cost vertically pointing radars located at the airport site itself to quantify amounts of supercooled cloud, drizzle, and rain over the airport.