Implementation Plan for the INCUS Mission

The Investigation of Convective Updrafts (INCUS) is a NASA Earth Ventures Mission. It is a Principal Investigator (PI)-led mission with a Class D risk classification [1]. The overarching goal of INCUS is to understand why, when, and where tropical convective storms form, and why only some storms produce extreme weather. Convective storms facilitate much of the vertical transport of water and air, a property typically referred to as convective mass flux (CMF), between Earth's surface and the upper troposphere. CMF within tropical convective storms plays a critical role in the weather and climate system through its influence on storm intensity, precipitation rates, upper tropospheric moistening, high cloud feedbacks, and the large-scale circulation. INCUS is the first space mission that provides tropics-wide observations of CMF using the time-differenced profiles of radar reflectivity from three small satellites. The INCUS flight system is composed of three satellites. They will be in the same orbital track covering the same swath, but at 30 and 90 seconds apart to measure time-differenced profiles of radar reflectivity. Each satellite has a multi-beam scanning Ka-band atmospheric radar based on the design flown on RainCube [2]. A deployable reflector at Ka-band is required to meet the horizontal resolution requirement. This reflector will be developed by Tendeg. The multi-beam scanning capability is required to collect the sufficient number of CMF measurements. The second satellite has a cross-track-scanning passive microwave radiometer with five channels (87, 165, 174, 178, and 181 GHz). The INCUS radiometer is a built-to-print of the successfully flown TEMPEST-D radiometer [3]. The INCUS spacecraft is a commercial-off-the-shelf (COTS) spacecraft developed by Blue Canyon Technologies. The launch services will be provided by the KSC Launch Services Program. The Science Data Center is located at Colorado State University's Cooperative Institute for Research in the Atmosphere. In this paper, we present the INCUS implementation plan that balances three important factors: 1) cost/schedule, 2) reliability, and 3) development challenges. The development challenges include supply-chain issues of electrical part availability and lead times, configuring the stowed payload architecture to meet various launch vehicle volume constraints, maintaining instrument design heritage, and interfacing to a COTS spacecraft. Various trade studies were conducted to improve the implementation reliability within the cost/schedule constraint.