Re: How does DO-178 treat OEM modules (with software)?


"Thomas Magma" <somewhere@xxxxxxxxxxxxxxxxxx> wrote in message
news:3XROh.86851$DN.28461@xxxxxxxxxxxx
A while back we had a short seminar on DO-178 and I asked the 'experts' how
DO-178 dealt with the software in modules from a third party (I used GPS as
an example). They said that as long as our software treated the GPS module
as a black box or a slave, that we didn't have to ensure that the GPS
module's software was DO-178. Is this true or still true? What about
modules in general? I have the standard but can't find the answer anywhere
in it.

Thomas Magma


There are allowances in DO-178B for using commercial-off-the-shelf (COTS)
software in a certified product, but only at safety level D. This
essentially would be for a avionics product could not result in the loss of
the aircraft. Higher levels of safety, i.e., Levels A, B and C can not use
untested software, either as part of an application or in a module that is
used in the application.

DO-178B software levels (A, B, etc.) are based on the potential of the
software to cause safety-related failures identified in the system safety
assessment. DO-178B has five levels of certification:
Level A: Software whose failure would cause or contribute to a catastrophic
failure of the aircraft.
Level B: Software whose failure would cause or contribute to a
hazardous/severe failure condition.
Level C: Software whose failure would cause or contribute to a major failure
condition.
Level D: Software whose failure would cause or contribute to a minor failure
condition.
Level E: Software whose failure would have no effect on the aircraft or on
pilot workload.

Scott
Validated Software


.

Relevant Pages

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