Low-thrust rocket engines (bus, vernier, divert, attitude control) operating at high altitudes can generate extended plume signatures with potential impact on forward-based missile-defense interceptor-seeker system performance. The signatures can include phenomena and features not exhibited for higher thrusts at lower altitudes. Advanced models and codes are required to account for all relevant chemical/physical phenomena from propellant combustion through engine performance to plume signature. To that end, relevant phenomena are identified and grouped by category (engine/core flow chemistry, plume/atmosphere molecular interaction, core/interaction spectral radiation) and evaluated against existing models and codes. Applicable tools and current deficiencies are identified and described. Methods are outlined to fill all apparent gaps and remedy all known deficiencies as the basis for a complete physical model incorporated in seamless simulation software supported by documented validation demonstrations.
Keywords: Low Thrust, Intrinsic Core, High Altitude, Atmospheric Interaction, Rocket Performance, Noncontinuum Flow, Plume Signature, Nonequilibrium Radiation
