Meeting & Exceeding Standards: Aerodynamic Hazards

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Equipment stored or operated on aircraft must withstand a variety of hazards, including acceleration, acoustic noise, temperature, vibration, water intrusion and altitude. A combination of these influences may also occur. MIL-STD-810G provides testing guidelines to ensure devices withstand hazards encountered during flight.

Acceleration

Structural: To evaluate a piece of equipment’s structural integrity under inertia loads induced by aircraft maneuvering or missile launches
Equipment is mounted to a centrifuge and brought to a specific speed to induce g factors within the expected environment. This speed is maintained for one minute. The test is repeated with the equipment positioned in six different orientations toward the centrifuge’s center: front, back, top, down, left and right facing.

Operational: To evaluate a piece of equipment’s operational integrity under inertia loads induced by aircraft maneuvering or missile launches
Testing is conducted as with Structural with the equipment in operation throughout the process. A track/rocket-powered sled can be used for this method if a centrifuge is not available.

Crash Hazard: To evaluate a piece of equipment’s hazard potential during an aircraft or missile crash
Testing is conducted as with Structural with speed increased to g factors simulating a crash.

Acoustic Noise

Diffuse Field: For equipment expected to operate in an environment, such as an aircraft or missile launch, with high intensity of acoustic noise
Test equipment is suspended or mounted in a reverberation chamber in such a way that all surfaces are exposed. Acoustic noise is applied through microphones for one minute and at a spectrum of frequencies according to the expected environment.

Grazing Incidence: For equipment likely to experience a high intensity of acoustic noise from one direction, such as with aircraft turbulence
Test equipment is mounted in a duct or progressive wave tube. Acoustic noise is applied through microphones for one minute and at a spectrum of frequencies according to the expected environment.

Cavity Resonance: For equipment stored within a cavity, such as a weapons bay, where oscillations of the structure and air within the cavity will likely occur
Test equipment is mounted in a cavity. Acoustic noise is applied through microphones for one minute and at a spectrum of frequencies according to the expected environment.

Temperature, Humidity, Vibration and Altitude

This portion of the standard covers testing electronic equipment on ground and flight operations. Testing can be conducted in a chamber capable of combining test elements or in a series of separate tests. Equipment is installed in its operational configuration. Temperature, humidity, vibration and altitude are adjusted in duration and level according to the highest stress conditions expected on missions.

Vibro-Acoustic and Temperature

This type of testing refers specifically to standards for external stores of aircraft, such as weapons, pods and fuel tanks on a captive carry flight. An acoustic chamber and vibration table are used for testing. Equipment is installed in its operational configuration. Vibration, acoustics and temperature are adjusted in duration and level according to expected flight mission conditions.

Sealevel Environmental Testing

Sealevel performs rigorous in-house testing and is experienced in creating rugged technology for operation in aerodynamic conditions.