The World's Largest Anechoic Chamber

- Image: The North Spin

Nestled in the Mojave Desert in the heartland of California is an interesting acoustic phenomenon: the world's largest anechoic chamber. Located on the Edwards Air Force Base, the Benefield Anechoic Facility is an important and rare part of the Air Force Flight Test Center. Though the Air Force Flight Test Center was first activated in 1951, the Benefield Anechoic Facility did not become a mainstay until the mid-80's.

More after the break.

For those not already familiar with anechoic chambers, they are rather large rooms that are constructed in such a manner that there are no echoes or reverberation. More commonly recognized for acoustic purposes, where reflections that normally affect frequency response can be avoided, anechoic chambers are also useful for Radio Frequency testing as well. This is precisely what the Benefield Anechoic Facility is for.

The architecture, engineering, and construction support services for this major complex have been provided since 1987 by DMJM (DBA Holmes & Naver, Inc.). The anechoic chamber supports ground testing of electronic warfare systems on full-scale aircraft and is a massive 250 x 264 x 70 foot steel plate box enclosed in a metal hangar building. The walls, ceiling, and floor are covered in 816,000 pyramidal foam cones designed to absorb radio frequency signals, and the chamber is RFI shielded to over 100dB. The center of the chamber is equipped with a 160 foot diameter turntable capable of rotating a full 360 degrees while holding objects with a mass of over one million pounds!


- Image: AECOM

The Benefield Anechoic Facility is considered an ideal ground test facility to investigate and evaluate anomalies associated with avionics, tactical missiles, and their host platforms. The vehicles can be operated in a controlled electromagnetic environment with emitters on and sensors stimulated while RF signals are recorded and analyzed.


- Image: Air Force Newsletter

The BAF has had some rather notable aircrafts tested within it, including the F-22 Raptor (pictured above), F-16 Fighting Falcon, MH-47 Chinook, and the C-130 Hercules. It also supports testing of various spacecraft, tanks, satellites, armoured vehicles, and was even used by BMW to test levels of magnetic interference on the upcoming 2004 models of the 530i, 545i, and the 645i.

No doubt about it: it's a rare and very cool facility. Almost makes me consider signing up for the Air Force just to get a chance to see it in-depth.