RP-1 and ethylene time histories have been measured during RP-1 pyrolysis, allowing determination of ethylene yields and overall fuel decomposition rates for RP-1 near 20 atm and between 1050 K and 1500 K. A decomposition surrogate for RP-1 was formulated using the components n-dodecane, methylcyclohexane, and iso-cetane by targeting three decomposition characteristics of the fuel: compound class, overall fuel decomposition rate, and ethylene yield. Decomposition of this surrogate mixture was modeled using a newly developed detailed mechanism and the simulations are compared to the experimentally measured RP-1 and ethylene time histories. Comparisons between modeled and measured ethylene yields and overall fuel decomposition rates are also reported. (C) 2012 Elsevier Ltd. All rights reserved.