The request to conduct an independent review of regression models, developed for determining the expected Launch Commit Criteria (LCC) External Tank (ET)-04 cycle count for the Space Shuttle ET tanking process, was submitted to the NASA Engineering and Safety Center NESC on September 20, 2005. The NESC team performed an independent review of regression models documented in Prepress Regression Analysis, Tom Clark and Angela Krenn, 10/27/05. This consultation consisted of a peer review by statistical experts of the proposed regression models provided in the Prepress Regression Analysis. This document is the consultation's final report. Parsons, Vickie s. Langley Research Center NASA/TM-2009-215745, NESC-RP-06-01/05-171-E, L-19680, LF99-8837 WBS 869021.06.07.04.99 EXTERNAL TANKS; LIQUID HYDROGEN; SPACE SHUTTLES; PRELAUNCH TESTS; VALVES; LEAKAGE; REGRESSION ANALYSIS; AEROSPACE SAFETY; AEROSPACE ENGINEERING; TECHNOLOGY ASSESSMENT; LAUNCHING