AEROSPACE REPORT NUMBER: TOR-2013(3909)-1, OBJECTIVE REUSE OF HERITAGE PRODUCTS (30-APR-2012)

AEROSPACE REPORT NUMBER: TOR-2013(3909)-1, OBJECTIVE REUSE OF HERITAGE PRODUCTS (30-APR-2012)., Developers of space flight equipment often look for opportunities to reuse heritage products as opposed to developing new equipment. Accordingly, heritage product reuse planning and processes are an integral part of the space system development process. However, there is no common approach across the space community to ensure a consistent assessment and risk evaluation of heritage products. The guidance contained herein was created to fill that void. Heritage and legacy designs are expected to cost less, work better, and be more reliable, but these assumptions at times have proven invalid. While it is common practice in the space industry to use heritage products, certain problems with this practice persist. Poor assumptions are sometimes made regarding the heritage hardware suitability for new programs. Proposals tout the value of heritage and legacy, but use has produced unintended consequences. Program schedules and budgets subsequently come under pressure to accommodate subtle differences in application, design, mission environment, and late arriving failure data. Mission failures can result from erroneous assumptions about the applicability of the requirements, configurations, performance, and reliability of heritage and legacy elements. These conditions have led to situations where industry and government have been surprised when a previously designed and developed product did not work as intended in a follow-on effort or in a new application or mission. When decisions regarding the reuse of products are based on inadequate examination of the heritage system applicability, this can lead to: misplaced confidence and aggressive assumptions (such as shortcuts in test) about the cost and schedule benefits of reuse; requirements/design modification and associated changes in verification methods; inaccurate assumptions for the behaviors of heritage designs causing interface problems, complex configurations, performance impacts, and operations errors. The term “heritage” lacks a common and industry-wide approach to objectively apply criteria to assess the hardware pedigree. This often leaves decisionmakers without appropriate tools and methods to make decisions regarding the reuse of heritage hardware. The lack of a space industry standard approach for evaluating the reuse of heritage products has resulted in guidance on the subject from industry/government teams. This document is a synthesis of that guidance, primarily in the area of using objective criteria to evaluate a program’s reuse decisions associated with heritage hardware. As opportunities develop to employ this guidance, refinements will be possible particularly with respect to providing examples and greater user advice.