6.4.1 Purpose
The purpose of system acceptance tests is to cover aspects relevant to the interre-lationship between two or more elements which constitute the system (i.e. space vehicle, launcher, ground segment) and to interfaces with other systems and projects.
6.4.2 System acceptance tests description
a. System acceptance tests include end-to-end tests between the launcher vehicle and the space vehicle, and space vehicle to ground segment compatibility (see clause 8).
b. Compatibility of all hardware and software elements of the overall command and control network, including the ground station(s), shall be demonstrated by a series of tests with the space vehicle in the various operative configur-ations.
c. System tests shall verify:
1. the capability of the ground station(s) to command and control the space vehicle;
2. the capability of the ground station(s) to perform tracking and ranging of the space vehicle;
3. the capability of the ground station(s) to receive and process the space vehicle telemetry data.
NOTE Details of the above tests are included in subclause 4.9.
7 Protoflight testing
7.1 Equipment test requirements
a. If the qualification equipment is planned for flight use, a protoflight approach shall be applied.
b. The equipment qualification testing shall be modified from that specified in subclause 5.1 to reduce cyclic stress levels.
c. For protoflight testing, the equipment acceptance tests defined in this Stan-dard need not be used with the exception of the burn-in acceptance tests (see subclause 6.1.12) and the qualification test baseline (see subclause 5.1) shall be applied with the following modifications:
1. For the equipment thermal vacuum test (see 5.1.15), the temperature extremes shall be 5 ºC greater than the minimum and maximum accept-ance temperatures (see 6.1.10).
2. For the equipment thermal cycling test (see 5.1.16), the temperature cycles shall be performed at 5 ºC greater than the minimum and maxi-mum acceptance temperature (see 6.1.11).
3. For the equipment sinusoidal vibration test, the test levels shall conform to subclause 5.1.10 with the exception that the number of sweeps shall be one sweep up and the sweep rate shall be 3 octave/min.
4. For the equipment random vibration test, the test levels shall conform to qualification levels in subclause 5.1.11 with the exception that the test duration shall be those for acceptance testing on each axis.
5. For the equipment acoustic test, the test level shall conform to qualifica-tion levels in subclause 5.1.12 with the excepqualifica-tion that the test duraqualifica-tion shall be those for acceptance testing (i.e. one minute).
6. For the equipment pyro shock test, the shock spectrum shall conform to subclause 5.1.13 with the exception that the number of shocks shall be one per direction.
7. For the equipment pressure test (see 5.1.8), only proof pressure tests as defined in subclauses 5.1.8.3 a. and 5.1.8.3 b. shall be conducted.
8. A burn-in test shall be performed if the total duration of the protoflight qualification test sequence is insufficient to detect material and workman-ship defect occurring in the equipment life. The total duration time shall be 250 hours minimum.
7.2 Subsystem test requirements
a. Subsystem protoflight testing should be performed according to subclause 5.2.
b. Environmental testing shall be performed for the qualification and accept-ance of the structure and thermal control subsystems but may be replaced by protoflight tests of these subsystems at a higher level, in combination with other subsystems during environmental test campaign.
c. Environmental protoflight test campaign can be conducted at subsystem level where this level of testing provides a realistic or practical test simulation (e.g.
design qualification of optical and telecommunication payloads).
d. Functional testing shall be performed with each subsystem assembled on a test bench which provides a flight representative environment (hardware and software) covering function, interfaces and performances.
7.3 Element test requirements
7.3.1 Space vehicle tests
The requirements of subclause 5.3 and Table 17 shall apply for the protoflight testing of space vehicle, with the following modifications:
a. The shock test shall be conducted according to subclause 5.3.3.6, with the exception that only 2 repetitions of activated events shall be performed.
b. The acoustic or random vibration tests shall be conducted according to sub-clauses 5.3.3.4 and 5.3.3.5.3, with the exception that:
1. the duration factor shall be 2 (instead of 4),
2. the duration shall be not less than one minute, and 3. the level margin for the flight environment shall be 3 dB.
c. The thermal vacuum test and the ambient thermal cycling test shall be per-formed according to subclauses 5.3.5.1 and 5.3.5.3, with the exception that the hot and cold temperature extremes shall be those used for qualification and the number of cycles shall be those used for acceptance (see Table 2).
7.3.2 Launcher tests
a. Protoflight test requirements should be applied at lower level than at the launch vehicle element level and subclauses 7.1 and 7.2 shall apply.
b. Element level tests should not be regarded as protoflight tests.
7.4 System test requirements
Protoflight test requirements need not be applied to systems.
NOTE System tests are not fundamentally environmental tests.
8 Pre-launch testing
8.1 General
8.1.1 Purpose
The purpose of pre-launch testing is to verify by end-to-end tests that each critical path in the system before launch is satisfactory, i.e. there are no out-of-tolerance conditions or anomalous behaviour, and to demonstrate successful integration of the space element with the launch element.
NOTE The pre-launch tests mainly affect space vehicles and launcher elements.
8.1.2 Pre-launch test objectives
a. Pre-launch tests shall verify that:
1. no damage or performance degradation of the space vehicle and its con-stituents has occurred during shipment or handling;
2. all launch site assembly activities are completed properly, all associated interfaces are verified, and their parameters are within the specified limits;
3. mating with the launch vehicle are completed successfully, i.e. all inter-faces between the space vehicle and the launch element, and between the launch element and the ground support facilities are verified.
b. The pre-launch tests shall provide data for trend analysis.
NOTE Trend analysis data can give evidence of a problem, even though all measurements were within tolerances.
c. The pre-launch test flow shall follow a progressive growth pattern to ensure the correct operation of each element involved (e.g. flight, launch and ground) prior to progressing to a higher level of assembly and test.
d. Pre-launch testing should consist of a partial repetition of acceptance test activities.
e. In cases where end-to-end testing cannot be performed with the flight hard-ware, simulation devices can be used to exercise the flight hardware to the maximum extent possible.
NOTE Not all end-to-end tests can be performed with only flight hardware (e.g. pyro devices and apogee burst motors).
f. Simulation devices should be carefully controlled and used only when there is no feasible alternative for conducting the test.
g. Redundancies shall be verified.
NOTE The extent of pre-launch testing, the appropriate test se-quences and the test procedures are unique for each launcher and for each project.