SAE AS7254

This document describes a method for measuring transient force histories generated by the impact of a soft or frangible projectile on a thin slicer oriented in a plane parallel to the direction of the projectile motion. The slicer is intended to be representative of a typical turbofan engine fan blade. The document describes the hardware and instrumentation required as well as the processing and data reduction required to compute force. In this test, a projectile impacts a relatively thin, flat, blade-like device with a sharp leading edge (the “slicer”). The direction of motion of the projectile is parallel to the plane of the slicer. The test is designed to minimize lateral motion in the projectile as a result of the impact. The intended impact velocity range for this test is between approximately 50 and 300 m/sec. The slicer has a width greater than the largest diameter of the projectile and is supported on a fixture instrumented to measure force. The projectile material is expected to be soft compared with the slicer material. Impact stresses are expected to be small compared with the yield strength of the slicer material so that any deformations in the slicer are elastic. This standard does not address all of the safety concerns associated with its use. It is the responsibility of each user of this standard to ensure that any safety issues are properly addressed. Measurements of forces generated by the dynamic slicing of soft projectiles can be challenging due to the very short duration of the event and the impracticality of producing a pure slicing response. This test provides a standard method for measuring these forces for comparison of one material to another. The method can be used to generate data useful in developing and validating computational material models for soft or frangible objects such as ice, soft polymers, and materials used to simulate birds used for aircraft certification testing. The method can also be used to develop physical simulants for impact and ingestion certification testing for aircraft.