A Successful Strategy for Satellite Development and Testing - Inpe

prime contractors by the government and ofthe subcontractors by the prime contractors.This increased the likelihood that problemscaused by streamlined design and verificationprocess changes at one level would notbe communicated to another.Another common shortfall in systemsengineering and verification planning involvedoverly optimistic assumptions aboutthe use of commercial off-the-shelf (COTS)or heritage components. In many cases, thedeveloper assumed that a commercial orheritage product was suitable for a new applicationwithout giving sufficient scrutiny tothe intended design use conditions. In reality,commercial or heritage products almostalways require more modifications thanexpected, and this adversely affects programschedule. Sometimes, problems with theseproducts were overlooked until they causedcostly failures in ground testing or even onorbit because assumptions regarding thesuitability of the original design to the newapplication’s actual design environment andoperational scenarios did not pan out.A Get-Well Road MapThe Aerospace study concluded with a seriesof specific recommendations for the nationalsecurity space community. In particular, acquisitionmanagers must:• strictly adhere to proven conservativedevelopment practices embodied in bestof-classspecifications and standards;• apply rigorous systems engineering, includingdisciplined peer design reviewsand clearly traceable verification processes;• emphasize requirements verification andtesting of all hardware and software,focusing on the early development phaseand lower-level unit design;• apply updated and consistent softwaredevelopment and verification processes,including meaningful metrics;• instill effective closed-loop design andcommunication processes, with specialattention to new technology insertion,application of COTS components, anddetailed assessment of operational dataand lessons learned;• strengthen the qualification and verificationof parts, materials, and processes;• develop a pyramidal and flight-like requirementsverification policy and assessthe risk of deviations from this policy;The Testing HandbookAerospace is developing a comprehensive test and evaluation handbook that will codifybest practices for planning a successful qualification and acceptance test strategy. Thishandbook will deal with the up-front planning and production phase as well as orbitalcheckout. The list of guidelines includes lessons learned from the study, such as:• Base schedules on realistic and executable models that account for system productionmaturity, reasonable levels of integration returns, and realistic problem resolution.• Plan a test program that implements a pyramidal requirements verification approach.• Test all high-power electronic units, including RF hardware, in thermal vacuum priorto system-level testing.• Ensure a conservative retest philosophy on all anomalous hardware that accounts forfatigue life from prior test exposures.• Develop an EMI/EMC control plan that ensures pertinent EMI/EMC testing at unitand appropriate levels of assembly and always conduct a system-level EMI/EMC testprior to the thermal vacuum test.• Perform early interface and harness compatibility checks on all hardware, preferablyduring development.• Plan for intersegment testing at the spacecraft level of assembly and include all flighthardware.• Plan for a rigorous verification and checkout of ground support equipment well inadvance of qualification testing.• Plan for a disciplined anomaly tracking and resolution process that determines rootcause on all anomalies and includes all factory, subcontractor, launch-base, andoperational anomaly data.• develop a set of engineering handbookswritten from the perspective of the systemprogram office;• manage the product life-cycle data withinthe system program office and across theenterprise and learn from it.When these practices are applied togetherthroughout development, they have historicallyresulted in successful program acquisitionsand mission success. Recommendationsfrom major government review panelsare largely consistent with Aerospace conclusionsregarding the proper application ofindustry best practices and lessons learned.Moreover, the Aerospace study providesdetailed evidence as to why national security,long-life, space acquisition—and morepointedly, the verification process—requiresa different approach than that of a purelycommercial space program. As a result, acquisitionleaders are once again emphasizinga more traditional, proven, and disciplinedapproach to engineering space systems.One critical part of such an approachis to ensure that appropriate specificationsand standards are applied on a given contract.Specifications and standards arisefrom an often painful and costly evolutionaryprocess, and in a sense, they form theembodiment of decades of lessons learnedand best practices. These specifications,standards, and guidelines therefore form thecornerstone of traditional best practices thathelp ensure successful execution of a satelliteprogram. Realizing this, Aerospace hasalready helped introduce revised and newnational security space standards for spacesystems development, which draw upon thepreviously canceled military standard withenhancements to bring them up to date withcurrent best practices.Additional best practices related to asuccessful qualification and acceptance teststrategy will be defined in a comprehensivetest and evaluation handbook under developmentat Aerospace. In addition, Aerospace isdeveloping and publishing handbooks thatCrosslink Fall 2005 • 9