5.13 software management control Flashcards
DO-178/12B
The aim of this document is to provide guidance to both the software developers and the certification authorities
Usually, acceptance of software is based on an agreement between the developer and the customer.
however In civil avionics
an independent third party, the certification authority, performs the ultimate system acceptance by certifying the entire aircraft
DO-178B/ED-12B established design assurance levels, based on a safety assessment process and hazard analysis, by examining the effects of a failure condition in each aircraft system.
there are 5 criticality levels what are they
level A - Catastrophic
Level B - Hazardous/Severe
Level C - Major
Level D - Minor
Level E - No Effect
DO-178C
the software specifies the
input and output parameters plus their respective tolerances
refreshment rates
fault detections
Modern LRUs contain their software in different packages called
Core software
Operational software or application software
Database
Only authorised personnel can modify level A software.
.
level E software can be handled by maintenance personnel (if the respective documentation is available)
.
in relation to software handling
in any case, it must be guaranteed that
Only the authorised software is influenced by re-loading
Successful loading must be acknowledged
No other systems are affected
Unapproved software changes can potentially lead to software failure, loss of aircraft control, and subsequent loss of life
.
there are several categories of software what are they:
Field-loadable Software (FLS)
Aeronautical databases
Factory-loaded software
what is field-loadable software (FLS)
Field-loadable Software (FLS) is any software that can be reconfigured, updated, or uploaded by technicians and manufacturers, like the avionics software
what are aeronautical databases
Aeronautical databases are not categorised as field-loadable software and are treated separately in regulations. These aeronautical databases may be a terrain database, a navigation database, an obstacle database, or an airport map database.
what is factory loaded software
Factory-loaded software is assumed not to change without replacing the device that it is on. To change factory-loaded software it is often necessary to break a seal and flash the memory. It may also be on read-only memory like an EEPROM.
what is the ultimate purpose of software management control procedures that offer definition documentation and details of the aircraft software process
to prevent unapproved software changes
