The Ariane 5 system was practically the same as the existing system, which had been abolished. It mainly had all the same features, but it technically didn’t match the specification and requirements of the new system. Due to this the system ceased to function and major losses of data were due to the specification and design errors in the software. The code for the system was adapted from the previous system and didn’t comply with the requirements.
The result of this was that the software design failed due to large errors of code and large amounts of important data about the flight control system was corrupted. There was no evidence that the flight control system was adequately analysed and tested by the IRS. The testing stage had no injection of realistic data input and there was no attempt to perform a closed loop system test. Due to insufficient testing the back up server didn’t respond to the system failing and ceased to function.
These errors would have been detected if a full testing regime had taken place to ensure that the system performed as expected. The system developers assumed that because the systems were similar no training would be necessary. Basically the users were put in the deep end with no knowledge of what the system actually did and with no support facilities. This contributed to the failure of the system because users didn’t know what the system was doing and at the same time wouldn’t have the knowledge to fix the problems.
(Question 2) Provide a comparative discussion in the context of software failures by comparing and contrasting the software development process, software quality issues and software project management of both systems. Looking at the two systems there are different development processes, such as the London Ambulance service was a new designed system where as the Ariane 5 system was just an existing system being updated. They are distinctly different from each other, as we will see:
The software development process is used to help the software developers gain knowledge into the proposed system and also the actual development of software. The LAS used some of the stages of the development process but didn’t meet all the criteria of the development process hence they didn’t investigate the proposed system correctly. They chose to miss stages and not to complete them so this led to the implementation of incomplete software that had involved a small amount of testing and training for the system as a whole.
Both systems were tested individually but they were not tested with realistic data, this is one of the main factors, which led to both of their failures. The Ariane 5 development process in comparison to the LAS was different. In order for this project to work correctly every piece of equipment had to be controlled exactly in order for the launcher to function. This meant that the attention was paid in the development and more importantly the testing to ensure full functionality. The Ariane 5 was developed differently as this system was an existing system, which just needed to be updated with the right information.