A purchase agreement for a full flight simulator has already been signed. The facility has already been prepared and is in anticipation of the new inhabitant. What follows next? How to ensure that the newly manufactured FFS operates properly or will serve successfully after the relocation is carried out?
Some terminology to keep in mind
Obviously, you, as a party acquiring the device, want to be guaranteed a top-quality and properly working FFS. So, how to be sure that it is so? It has to fully meet CS-FSTD A requirements. Now a question might come up, what this CS-FSTD A means. On the whole, the abbreviation stands for Certification Specifications for Aeroplane Flight Simulation Training Device. The European Aviation Safety Agency defines this as an issue “describing the requirements a FSTD has to comply with in order to achieve a certain level of qualification (initial qualification) and to maintain this level of qualification (recurrent qualification)”.
To make it easier to comprehend, this is a standard procedure which is carried out to describe the performance, handling qualities and documentation requirements of the FSTD and its compliance with the applicable processes for flight crew member training, testing and checking. Therefore, various types of FSTDs have to comply with different technical standards and pass different validation tests as well as functional and subjective tests.
What lies behind the procedure?
First of all, the FSTD operator must run the complete Qualification Test Guide (QTG), which includes validation, functions & subjective tests, between each annual evaluation by a competent authority. This is the primary reference document used for evaluating a FSTD.
EASA describes it as a document designed to demonstrate that the performance and handling qualities of a FSTD are within the prescribed limits with those of an aircraft, a class of aircraft or type of a helicopter and that all applicable requirements have been met.
The FSTD should be assessed in those areas that are essential to completing the flight crew member training, testing and checking process. This includes the FSTD’s longitudinal and lateral-directional responses; performance in take-off, climb, cruise, descent, approach, landing; specific operations; control checks; flight deck, flight engineer, and instructor station functions checks; and certain additional requirements depending on the complexity or qualification level of the FSTD. Also, the motion and visual systems should be evaluated to ensure their proper operation.
The FSTD operator may elect to accomplish the QTG validation tests while the FSTD is at the manufacturer’s facility. Tests at the manufacturer’s facility should be accomplished at the latest practical time prior to disassembly and shipment. Then the FSTD operator should validate FSTD performance at the final location by repeating at least one-third of the validation tests in the QTG and submitting those tests to the competent authority.
Depending on the type of a FSTD, the number of tests might vary reaching up to 300.
Validation tests. What is the purpose?
Validation tests are a part of objective evaluation. These tests are carried out in order to compare simulator performance to the performance of an aircraft. The results should certainly match the tolerances specified for the test to pass. During both initial and recurrent evaluations, the baseline simulator performance is established against the standard.
Notably, when conducting recurrent evaluations, simulator performance is required to be compared to the baseline performance as well. It means that the results of the recent evaluation should be checked with data in the Master Qualification Test Guide (MQTG), to identify any change in performance. Wondering what the MQTG is? Master qualification test guide (MQTG) is the competent authority approved Qualification test guide (QTG) which incorporates the results of tests witnessed by the competent authority.
The MQTG serves as the reference for future evaluations.
So, this comparison is used as an indication that the configuration control system is used properly as well as allows for engineers or technicians to notice any problems at an early stage, preferably prior to the next recurrent evaluation.
As a minimum, the QTG tests should be run progressively in at least four approximately equal three-monthly blocks on an annual cycle. Each block of QTG tests should be chosen to provide coverage of different types of validation, functions and subjective tests.
To make it clear, let’s look into an example. In case a technical team checks one of the motion legs in Q1, it does not mean that they will inspect the whole motion system during the Q1. Correspondingly, other motion legs will be checked during the following quarters, for the motion system to be monitored continuously, but not only once in a year.
As for the results, they should be dated and retained in order to satisfy both the FSTD operator as well as the competent authority that the FSTD standards are maintained. It is not acceptable that the complete QTG is run just prior to the annual evaluation.
Types of validation tests to be applied
It has already been mentioned that validation tests can be automatic, manual or even integrated. Earlier validation tests were run manually, including the setting up of the simulator initial conditions. Nevertheless, better design techniques, together with the regulatory authority requirements for recurrent testing of the simulator at regular intervals, has enabled all validation tests to be performed automatically, using computer-driven stimuli. Automatic tests are carried out fairly quickly; it might take only four days to check a FFS.
Meanwhile, manual checks last longer and are meant to cross-check and verify automatic testing. During manual testing a pilot conducts the test without computer inputs except for the initial setup. In general, all manual tests must meet the same performance match as the automatic tests.
Integrated testing, in turn, is important to validate the overall integrated simulator systems. For example, if one system has successfully passed the check, it does not mean that all systems perform in a satisfactory manner when integrated. This is the matter that is highly recommended to be checked with the help of integrated assessment.
Functions and subjective tests. Let’s do the check.
Validation tests are only one of the stages of the whole FSTD testing process. Now, let’s understand what lies behind the functions and subjective tests. These tests are quantitative and/or qualitative assessment of the operation and performance of an FSTD by a suitably qualified evaluator. The test can include verification of correct operation of controls, instruments, and systems of the simulated aircraft under normal and non-normal conditions.
Accurate replication of aircraft systems functions must be checked at each flight crew member position. This includes procedures using the operator’s approved manuals, aircraft manufacturers’ approved manuals and checklists. Handling qualities, performance and simulator systems operation must be subjectively assessed.
In order to ensure the functions tests are conducted in an efficient and timely manner, operators are encouraged to coordinate with an appropriate regulatory authority responsible for the evaluation so that any skills, experience or expertise needed by the regulatory authority evaluation team are available.
Therefore, in case during the functions tests the pilot evaluator notices that something differs from an aircraft, it must be corrected to the limits of the technology.
In case some repair works are not needed, all the procedure is completed with the reports on the FSTD condition and possibility to further operate the device. Thus, it is absolutely clear that the process is not that easy and quick to manage. Whether you are preparing the facility, or you are underway checking you FSTD, hard work and determination are the key aspects that should lead you all the way.