A: Some quotes on the background and accuracy of the CRASH program:
- (see the Reference list contained in the papers cited).
- (and note i broke the quote into multiple lines here)
- "After SMAC was created and delivered to researchers at NHTSA they requested Calspan create a program to provide initial starting speeds for a SMAC Reconstruction analysis.
- CRASH was created to assist SMAC users in determining first estimates of the impact speeds.
- The original CRASH program utilized both piecewise-linear trajectory solution procedures and a damage analysis procedure to provide an initial estimate.
- The CRASH program was subsequently adopted by NHTSA as an integral part of the National Accident Sampling Study (NASS) investigations.
- The rationale for the use of the CRASH program was that for statistical studies, the average error in severity determinations is more important than any individual errors.
- The CRASH program, with it's question and answer mode, vehicle categorization, single step solutions procedure, and most importantly low cost, redirected the NHTSA interest from SMAC towards the CRASH computer program".
From the 1986 paper ?A Revised Damage Analysis Procedure for the CRASH Computer Program"
- "the original formulation of the CRASH computer program (e.g., References 3 and 4) had limited objectives in terms of detailed accuracy,since it was developed for the primary purpose of serving as a simple pre-processor for use with the SMAC simulation program (Reference 5)."
- "The original form of the CRASH [1, 2, 3, 4] computer program, which culminated in the CRASH3 version, was not intended to be a detailed, highly accurate reconstruction program. Rather, it was developed to serve as a simple preprocesser for the SMAC program. While the results of CRASH3 applications can be useful in providing approximate measures of accident severity for use in statistical studies, where the average error is most important, it has been demonstrated in validation tests to produce results which when compared to those of full-scale crash tests can include individual errors as great as 45%.
- the original NHTSA CRASH3 technical manual using the CRASH3 tables the following is the accuracy from Figure 1.1 "Comparison of True Vs CRASH3 Damage estimates for DELTAV for 53 staged collisions" (page 1.4): (and this is the3 same for EDCRASH and other CRASH clones)