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The reduced dynamic technique (RDT) has become popular for removing unmodeled dynamic error. In particular the technique is useful for removing errors caused by poor atmospheric modeling. This paper examines the ability of the technique to remove drag error at a range of low altitudes where the error was simulated by perturbing the drag coefficient. The orbit determination was performed using simulated GPS flight receiver data with the GIPSY-OASIS II software package. The RDT sigma's for minimizing orbit error in the radial, cross track, and along track directions, and for minimizing the three dimensional position error are presented for a variety of low altitude, sun synchronous orbits. In an autonomous application, RDT removes drag as a significant error source at altitudes above about 350 kilometers. Also, for this altitude regime, the optimum sigma is nearly the same whether or not drag error is included in the solution.