An airborne cloud profiling radar (SPIDER) which has several unique features has been developed at CRL. In this paper, the objectives and design considerations are outlined, and the system is described. The features of SPIDER are summarized below. (1) A W-band frequency (95 GHz) is used to provide very high sensitivity to small cloud particles. (2) The radar is carried by a jet aircraft that can fly high above most clouds. (3) Full-polarimetric and Doppler capabilities are incorporated in the unit. (4) Almost all radar operational parameters are under software control, and most processing is in real time. (5) The design gives consideration to the study of cloud radiation and microphysics. The system has been completed and is still undergoing performance testing. The functions and performance of the SPIDER system are currently fulfilling the intentions of its design. Several interesting cloud features that had not been seen with previous instruments have already been observed.

A new airborne rain radar named CAMPR (CRL Airborne Multiparameter precipitation Radar) has been developed for the major purpose of calibrating PR (Precipitation Radar) onboard TRMM (Tropical Rainfall Measuring Mission; scheduled to be launched in 1997) in orbit by observing the same rain with both CAMPR and TRMM satellite. CAMPR operates as a coherent radar at 13.8 GHz, the same frequency as TRMM-PR, and has polarimetric and Doppler capabilities. It is installed on a relatively small aircraft and can scan the antenna over a wide angle range, from the nadir to the near-horizon. These functions have been verified to work well and it is shown that the radar system is accurately calibrated. Examples of measurement data show CAMPR's high capability to extract various quantities relating to precipitation and cloud physics. Before the TRMM launch, CAMPR is being used to obtain TRMM-PR simulation data to help its algorithm development as well as to obtain data concerning precipitation and cloud physics.