{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Nasa usually chooses to contract with industry for

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: operations") Phase E—Operations ("operate the system and dispose of it properly"). Phase A efforts are conducted by NASA field centers; such efforts may rely, however, on pre-Phase A inhouse and contracted advanced studies. The majority of Phase B efforts are normally accomplished by industry under NASA contract, but NASA field centers typically conduct parallel in-house studies in order to validate the contracted effort and remain an informed buyer. NASA usually chooses to contract with industry for Phases C and D, and often does so for Phase E. Phase C is nominally combined with Phase D, but when large production quantities are planned, these are treated separately. Alternatives to the project phases described above can easily be found in industry and elsewhere in government. In general, the engineering development life cycle is dependent on the technical nature of what's being developed, and the project life cycle may need to be tailored accordingly. Barry W. Boehm described how several contemporary software development processes work; in some of these processes, the development and construction activities proceed in parallel, so that attempting to separate the associated phases on a time line is undesirable. Boehm describes a spiral, which reflects the doctrine of successive refinement depicted in Figure 3, but Boehm's spiral describes the software product development process in particular. His discussion applies as well to the development of hardware products as it does to software. Other examples of alternative processes are the rapid prototyping and rapid development approaches. Selection of a product development process paradigm must be a case-dependent decision, based on the system engineer's judgment and experience. Sometimes, it is appropriate to perform some long-lead-time activities ahead of the time they would nominally be done. Long-lead-time activities might consist of technology developments, prototype construction and testing, or even fabr...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online