Expert ground segment and mission operations engineering — ground station network design, pass planning and contact analysis, CCSDS TT&C protocols, data processing pipelines, and MOC architecture. Use when sizing ground networks, calculating contact windows, estimating daily data volume, designing operations concepts, or selecting between DSN/ESTRACK/KSAT/commercial providers. Trigger with "ground station", "pass planning", "contact window", "mission operations", "telemetry", "telecommand", "DSN", "ESTRACK", "KSAT", "data downlink", "MOC design", "CCSDS".
Expert launch operations and integration engineering — launch site selection, rideshare vs dedicated trades, adapter and separation system selection, countdown timelines, deployment sequence design, and launch window calculation. Use when selecting a launch site, planning a launch campaign, sizing adapters, calculating latitude penalties, designing deployment sequences, or evaluating rideshare options. Trigger with "launch site", "countdown", "rideshare", "deployment sequence", "launch window", "ESPA", "separation system", "launch campaign", "launch manifest", "range safety".
Lead systems engineer and mission architect — the integrating function across all spacecraft subsystems. Owns top-level budgets (mass, power, data, delta-v, thermal, link, cost), requirements decomposition (L0-L4), mission phase planning (Phase 0 through F per ECSS/NASA), design review gates (SRR, SDR, PDR, CDR, TRR, FRR, LRR), trade study methodology (Pugh matrix), and system-level verification. Trigger with "mission architecture", "systems engineering", "mass budget", "power budget", "trade study", "design review", "PDR", "CDR", "requirements decomposition", "margin policy", "mission design".
Orbital mechanics and astrodynamics for spacecraft mission design. Covers Keplerian orbital elements, two-body and restricted three-body problems, Hohmann and bi-elliptic transfer orbits, constellation design using Walker delta patterns, launch window analysis, porkchop plots for interplanetary trajectories, ground track analysis, and station-keeping budgets. Trigger with "orbit", "transfer orbit", "constellation", "launch window", "Hohmann", "Keplerian", "inclination change", "delta-v", "ground track".
Expert rocket propulsion analysis — engine selection, delta-v budgets, staging optimization, mission architecture, and propellant trade studies. Use when designing launch vehicles, evaluating engine performance, calculating orbital mechanics, comparing propulsion systems, or reviewing mission feasibility. Trigger with "rocket engine", "delta-v", "staging", "launch vehicle design", "propulsion trade study", "Tsiolkovsky", "specific impulse", "thrust-to-weight", "payload to orbit".
Expert spacecraft guidance, navigation and control (GNC) / attitude determination and control systems (ADCS) analysis — sensor selection, actuator sizing, pointing budgets, disturbance torque analysis, control mode design, and momentum management. Use when designing ADCS architectures, selecting star trackers or reaction wheels, calculating gravity gradient torques, building pointing error budgets, or evaluating slew performance. Trigger with "attitude control", "ADCS", "reaction wheel", "star tracker", "pointing budget", "GNC", "guidance navigation", "CMG", "momentum wheel", "magnetic torquer", "sun sensor", "disturbance torque", "slew maneuver", "detumble".
Expert payload and instrument engineering — optical sizing, detector selection, spectral band design, data rate budgets, and science operations planning. Use when designing Earth observation cameras, spectrometers, SAR payloads, lidar systems, or radiometers. Covers GSD calculation, diffraction-limited aperture sizing, MTF analysis, SNR estimation, compression trade studies, and mass/power estimation. Trigger with "payload design", "instrument", "camera", "GSD", "aperture", "spectrometer", "data rate", "remote sensing", "optical payload", "SAR", "hyperspectral", "lidar", "radiometer", "detector", "focal length".
Expert spacecraft electrical power system engineering — solar array sizing, battery selection, power budget analysis, eclipse energy balance, RTG sizing, and bus architecture trades. Use when designing EPS subsystems, sizing solar arrays for any orbit, selecting batteries for eclipse support, building power budgets by mode, evaluating RTGs for deep space, or reviewing end-of-life power margins. Trigger with "solar array", "power budget", "battery sizing", "eclipse power", "RTG", "solar panel", "power system", "EPS", "depth of discharge", "energy balance", "power bus".