Penetrating insights: NIST airframe tests help ensure better shielding for flight instruments

Aug 26, 2009
This photo shows testing equipment being used by NIST scientists in recent research mapping radio frequency penetration of airframes, in this case a Boeing 737-200. The data from the tests provided valuable independent data on how electromagnetic radiation penetrates commercial aircraft, thereby helping improve safety. Credit: NIST

Airline travelers are used to being instructed to turn off computers and cell phones during takeoffs and landings as a precaution against interfering with the plane’s navigational equipment, but outside sources of high-energy interference can be even more dangerous. Recent tests by researchers at the National Institute of Standards and Technology will provide much needed, independent data on how electromagnetic radiation penetrates aircraft, helping to ensure continued air travel safety.

The (FAA) requires manufacturers to demonstrate that their aircraft have effective high intensity radiated field (HIRF) protection. The manufacturers conduct tests on their aircraft and provide those results to the FAA as part of the certification process. The tests are designed to show where and to what extent , across a wide spectrum of frequencies, penetrates a given craft’s airframe. This information is important in determining if and where shielding is needed to protect vital electronic instrumentation from malfunction or damage while flying through ground-based radar beams, for example.

This effort was undertaken to assist the FAA with HIRF measurement procedures and data processing methodologies. The FAA has struggled with data sets provided by HIRF testers because they use a wide range of measurement/data processing techniques that are not standardized.

For an independent analysis of the situation, a NIST team recently performed HIRF tests on three representative aircraft to give FAA officials a frame of reference for the procedures and data reduction techniques used for typical low-level airframe HIRF attenuation/shielding tests. Having this information will help the FAA ensure that commercial aircraft are indeed meeting minimum shielding requirements and, ultimately, make the safety of tested aircraft more transparent. “This will get everyone on the same page,” says Chriss Grosvenor, a NIST electronics engineer. “The FAA and aircraft manufacturers now have a lot of unbiased data they can look at, and our method is just another method to obtain that information.”

The three aircraft chosen for the representative tests were a Boeing 737-200 and a Bombardier Global 5000 business jet, both owned by the FAA, and a Beechcraft Premier IA carbon-fiber composite business jet, owned by the Hawker-Beechcraft company. By measuring all three aircraft and comparing the results, NIST was able to provide a guide for the optimization of HIRF testing standards for the EMC aircraft manufacturing community. The tests were conducted over a two-year period using a commercial measurement system that incorporates NIST-developed ultra-wideband antennas, a network analyzer and an optical fiber link to obtain high-resolution measurements from the megahertz to gigahertz range. NIST-developed special software extends the number of frequencies to any desired value using a variable number of bands.

More information: C. Grosvenor, D. Camell, G. Koepke, D. Novotny and R.T. Johnk. Electromagnetic airframe penetration measurements. Paper presented at the 2009 IEEE International Symposium on Electromagnetic Compatibility, Austin, Texas, Aug. 17-21, 2009.

Source: National Institute of Standards and Technology

Explore further: Lifting the brakes on fuel efficiency

add to favorites email to friend print save as pdf

Related Stories

NIST shielding data help launch shuttle

Sep 12, 2005

As the National Aeronautics and Space Administration (NASA) plans for the next launch of the space shuttle, a critical aspect of the program's safety is being assured by 5 million pieces of data collected recently by the ...

FAA FUEL TANK SAFETY SYSTEM TESTED AT NASA

Jul 07, 2004

An aircraft normally used to transport the Space Shuttle has been pressed into service to test technology to make airliners safer. Researchers from the NASA Glenn Research Center (GRC), Cleveland, arranged for a fuel iner ...

Quieter, cleaner airplane landings on the way

Jan 14, 2005

An experimental procedure that substantially reduces the noise of descending aircraft is one step closer to availability for commercial air carriers, thanks to the continuing efforts of a research team led by Professor John-Paul ...

Audit: Air traffic systems vulnerable to attack

May 06, 2009

(AP) -- The nation's air traffic control systems are vulnerable to cyber attacks, and support systems have been breached in recent months allowing hackers access to personnel records and network servers, according to a new ...

New system helps aircraft avoid turbulence

Sep 06, 2007

A new turbulence detection system now being tested is successfully alerting pilots to patches of rough air as they fly through clouds. The system, designed by the National Center for Atmospheric Research (NCAR) ...

Recommended for you

Lifting the brakes on fuel efficiency

Apr 18, 2014

The work of a research leader at Michigan Technological University is attracting attention from Michigan's Governor as well as automotive companies around the world. Xiaodi "Scott" Huang of Michigan Tech's ...

Large streams of data warn cars, banks and oil drillers

Apr 16, 2014

Better warning systems that alert motorists to a collision, make banks aware of the risk of losses on bad customers, and tell oil companies about potential problems with new drilling. This is the aim of AMIDST, the EU project ...

User comments : 0

More news stories

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.

Health care site flagged in Heartbleed review

People with accounts on the enrollment website for President Barack Obama's signature health care law are being told to change their passwords following an administration-wide review of the government's vulnerability to the ...