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Error Cost Escalation Through the Project Life CycleIt is well known that the costs to fix errors increase as the project matures, but how fast do those costs build? A study was performed to determine the relative cost of fixing errors discovered during various phases of a project life cycle. This study used three approaches to determine the relative costs: the bottom-up cost method, the total cost breakdown method, and the top-down hypothetical project method. The approaches and results described in this paper presume development of a hardware/software system having project characteristics similar to those used in the development of a large, complex spacecraft, a military aircraft, or a small communications satellite. The results show the degree to which costs escalate, as errors are discovered and fixed at later and later phases in the project life cycle. If the cost of fixing a requirements error discovered during the requirements phase is defined to be 1 unit, the cost to fix that error if found during the design phase increases to 3 - 8 units; at the manufacturing/build phase, the cost to fix the error is 7 - 16 units; at the integration and test phase, the cost to fix the error becomes 21 - 78 units; and at the operations phase, the cost to fix the requirements error ranged from 29 units to more than 1500 units
Document ID
Acquisition Source
Johnson Space Center
Document Type
Conference Paper
Stecklein, Jonette M.
(NASA Johnson Space Center Houston, TX, United States)
Dabney, Jim
(Houston Univ.-Clear Lake Houston, TX, United States)
Dick, Brandon
(Boeing Co. Houston, TX, United States)
Haskins, Bill
(Boeing Co. Houston, TX, United States)
Lovell, Randy
(Northrop Grumman Corp. United States)
Moroney, Gregory
(Wyle Labs., Inc. Houston, TX, United States)
Date Acquired
August 25, 2013
Publication Date
June 19, 2004
Subject Category
Economics And Cost Analysis
Report/Patent Number
Meeting Information
Meeting: 14th Annual International Symposium
Location: Toulouse
Country: France
Start Date: June 19, 2004
End Date: June 24, 2004
Sponsors: International Council on Systems Engineering (INCOSE) Foundation
Distribution Limits
Public Use Permitted.
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