(2) Conservative loading and the required deformations for the test articles, should be documented and included in the test report.
(3) Placement and characteristics of electronic and photographic instrumentation chosen for the test, beyond that information provided by the facility, should be documented. This can include special targets, grids or marking used for metric interpretation of photodocumentation, and transducers and data channel characteristics for lap belt loads, floor reaction forces, or other measurements beyond those discussed in this AC.
(4) Any unusual or unique activity or event pertinent to conducting the test should be documented. This may include use of special "break away" restraints or support for the test dummies, test items or transducers, operational conditions or activities such as delayed or aborted test procedures, and failures of test fixtures, instrumentation system components or anthropomorphic test dummies.
c. Test Report. The documentation should include the test proposal and procedures, all test results, analyses, and conclusions. The data should include charts, listings, and/or tabulated results, and copies of any photoinstrumentation used to support the results. In addition, as a minimum, the following should be included in the test result section of the test report.
(1) Impact pulse shape (reference paragraph 7b).
2) The HIC results for all tests where the test dummies are exposed to secondary head impact with interior components (reference paragraph 7c) or head strike path and velocity data where secondary head impact is likely but is not evaluated by the tests (reference paragraph 7c).
(3) Impact velocity (reference paragraphs 7b(7)(i) and 7d).
(4) Upper torso restraint system load, if applicable (reference para graph 7e).
(5) Compressive load between the pelvis and the lumbar column (reference paragraph 7f).
(6) Retention of upper torso restraint straps, if applicable (reference paragraph 7g).
(7) Retention of lap safety belt (reference paragraph 7h).
(8) Seat attachment (reference paragraph 7i).
(9) Seat deformation (reference paragraph 7j).
9. COMPUTER MODELS. Several computer-based analytical models have been developed to represent the seat/restraint/occupant system in a crash. Some of these models include a seat-occupant model for Part 23 airplanes and also a representation of the vehicle interior or the complete airplane as well. These models can vary in complexity from simple spring-mass dynamic models to exceedingly complex models which can be of help in designing the seat/restraint/interior system. Validation of these models also varies from no validation at all to complex validation efforts based on controlled testing and field experience. The use of these models during the design phase of the seat/restraint/interior systems for civil airplanes is They can be of great assistance in predicting conservative test conditions, in understanding the performance of systems when used by various sized occupants, in estimating head strike paths and velocities, and for many other uses of interest to the designer. However, at the present time, none of these computer models have been validated to be sufficient alternatives to the dynamic tests discussed in this AC. The Federal Aviation Administration continues to assess the performance of dynamic computer-based models, and may issue appropriate advisory material should any of these computer model/techniques be found to be an acceptable alternative to the tests discussed in this AC.
DON C. JACOBSEN Acting Manager, Small Airplane Directorate Aircraft Certification Service 26