Risk reduction measures
Having identified the risks the next stage is to decide how they might be mitigated as much as possible. The measures which can be taken are known as risk reduction measures (RRM) and are typically divided into five main categories:
(1) Training: Correct and comprehensive training of the test team is vital to reducing the risk on any test programme. This training will be required on the aircraft itself and in the case of initial trials on a new aircraft encompasses the ground instruction, simulator training, conversion course and continuation training. On other aircraft it may only involve currency training on type. The training may also involve the practise and perfection of the test techniques to be used or the flight skills to be employed during the programme, such as night flying, NVG instrument flying. Safety and survival training for all crew members is also conducted.
(2) Supervision: The close supervision of the test programme from the initial inception of the requirement, through the raising of the trials instruction (TI), the test plan and the individual flight authorization is possibly the single most important RRM. It is often the greater experience and the objectivity of those in a supervisory position which is able to identify possible risks that may not be apparent to those who are intimately involved in the programme itself. The individuals with supervisory responsibility may also be able to identify any inadequacies with the performance of the trials personnel and take action accordingly.
(3) Procedures: The application of logical procedures enables any potential risks to be reduced. These include the method to be used for setting up test points, gathering data and recovering to a normal flight condition. In addition procedures are developed to cover emergencies and other unexpected events. These procedures are laid out in detail in the test plan for the flight(s) and are reviewed during the pre-flight briefing prior to authorization. Procedures are also developed for the dissemination of results and information within the test team and within the test establishment; this is particularly important where changes may be made to the test aircraft during the test programme.
(4) Limitations: Every flight and test programme is subject to a variety of limitations some of which are imposed by the manufacturer; the others are imposed by the test establishment. The limitations may be imposed for structural considerations, to prevent damage to systems, for handling reasons, or to enhance flight safety. In every case it is essential that all participants are aware of every limitation and that they are respected during all flights. The limitations are detailed in the test plan and revised in the pre-flight brief.
(5) Monitoring: The monitoring of a test programme or flight can take a variety of forms all of which may be employed if appropriate. This monitoring usually involves the comparison of the actual results with the anticipated results to ensure that the programme is progressing in the expected manner: a lack of correlation between these results may indicate that not all factors have been addressed correctly during the planning stage and therefore the plan should be reassessed. The comparison of actual with anticipated results is also conducted for individual flights. In addition the actual results in flight are assessed for each test point prior to moving on to the next increment; this may require the use of telemetry to a ground monitor or the use of in-flight plots to predict the likely results from the next point. External monitoring of the flight may also be employed through the use of chase aircraft and ground observers.