MIL-STD-1530C(USAF)
5.2.16 Initial risk analysis.
An initial risk analysis shall be performed using the EIFS distribution developed under 5.2.14.1 and 5.3.4 and combined, when appropriate, with data from similar aircraft. A primary objective of this analysis is to demonstrate a low risk of both WFD and loss of fail-safety during the design service life when the aircraft is flown to the design loads/environment spectrum. Also, the analysis should estimate the time beyond the design service life when the risk of loss of fail-safety will become unacceptable. For non-fail- safe structures, the analysis should estimate the time beyond the design service life when required safety inspections and/or modifications would result in an unacceptably high risk of aircraft unavailability
and/or adverse economic consequences. All significant variables impacting risk shall be included in the risk analysis. Examples of such variables include: EIFS distribution, load spectra, chemical and thermal environment, material properties, and the NDI probability of detection.
5.3 Full-scale testing (Task III).
The objective of this task is to assist in the determination of the structural adequacy of the design through a series of ground and flight tests. Test plans, procedures, and schedules shall be approved by the USAF. Test results shall be used to validate analytical design data and to verify requirements are achieved.
5.3.1 Static tests.
A static test program shall be conducted on an instrumented aircraft using simulated loads derived from critical flight and ground handling conditions. Thermal environment effects shall be simulated in addition to the load application on aircraft structures where operational environments impose significant thermal effects. The primary purpose of the static test program is to verify the static strength analyses and the design ultimate strength capabilities of the aircraft structure. Deletion of the full-scale ultimate load static tests is generally unacceptable. However, a separate full-scale static test is not required if any of the following conditions are met and specifically approved by the acquisition authority:
a. where it is shown that the aircraft structure and its loading are essentially the same as that of a previous aircraft structure which was verified by full-scale tests; or
b. where it is shown that the strength margins (particularly for stability-critical structures) have been demonstrated by major assembly (i.e., entire wing, fuselage, and/or empennage component) tests; or
c. strength demonstration proof tests are performed to 115 percent of design limit load on every flight aircraft to be operated. These proof tests shall demonstrate that deformation requirements have been met and shall validate the accuracy of the strength predictive methods.
Major repairs, extensive reworks and refurbishments, and component modifications which alter the structural load paths, or which represent significant changes in structural concept, shall require a static ultimate load test of the affected component.
5.3.1.1 Selection of test article.
The test article shall be an early System Development & Demonstration phase test aircraft structure and shall be representative of the operational configuration (including all significant structural details) and manufacturing processes. If there are significant design, material, or manufacturing changes between the test article and production aircraft, static tests of an additional article or selected components and assemblies thereof shall be required.
5.3.1.2 Schedule requirements.
Full-scale static tests and/or strength demonstration proof tests shall be scheduled such that the tests are completed in sufficient time to support removal of flight restrictions on flight test and operational aircraft in support of program requirements.
21
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business