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Thursday, October 1, 2015

Top Cover

In the U.S., civil customers lack fresh and impartial data on helmets and their effectiveness.

By Joseph Ambrogne

 

A transposed rendering of helmets, from left to right: Gentex Corp.'s ALPHA Eagle, Evolution Helmets' EVO 252 and Gentex's HGU-56. Photos courtesy of Gentex Corp. and Helicopter Helmet, LLC

In April 2015, personnel from the FAA’s Rotorcraft Directorate and its Civil Aerospace Medical Institute discussed the results of their analysis into the effects of post-crash fires during 125 fatal helicopter accidents between Oct. 13, 2008, and Sept. 27, 2013. The team initially set out to determine how often post-crash fires contributed to helicopter fatalities, how much crash-resistant fuel systems reduced that number and what factors were responsible for the remaining fatalities.

But what it found was that regardless of the fuel system used, “blunt force trauma is the bigger concern in fatal rotorcraft accidents, even in cases of post-crash fire.” In helicopters without crash-resistant fuel systems, the researchers determined blunt-force injuries contributed to 80% of crash fatalities. The analysis concluded with a number of questions to the industry, among them: “In fatal rotorcraft accidents, skull injuries are cited in 50% of cases and brain injuries in 65% of cases. Knowing this, do you wear a helmet?”

The FAA does not mandate the use of helicopter-pilot helmets. It also does not standardize the ways they are tested and certified or how such information is communicated to the public. A pilot’s decision between two helmets can seem like comparing apples to oranges. On top of this, there is a surprising lack of data from civil accident investigations to show if and how specific helmets actually help in a crash. Safety experts and helmet manufacturers alike believe the rotorcraft industry should come together and make sense of what can be a confusing market.

Where is the Data?

On top of the lack of mandate, neither the FAA nor any other U.S. government agency appears to have studied the effects of specific helmet designs—or even helmets in general—on helicopter-accident survivability. Even the National Transportation Safety Board has, so far, refrained from collecting helmet-specific data, despite its mandate to investigate air accidents. The board told R&WI that “as part of any of NTSB investigations, additional data [is] captured on an issue where it is appropriate … and that information will be released after a complete analysis. There is not such information available from NTSB at this time.”

Such highly regarded research is conducted extensively by the U.S. military, though it has been more than two decades since the results of such tests have been released. (The Army is currently studying crash performance of its HGU-56/P helmet.) According to a U.S. Army Aviation Research Laboratory report published in 1992 titled Flight Helmets: How They Work and Why You Should Wear One (Report No. 93-2), “the most compelling evidence regarding helmet effectiveness is actual crash injury data.”

The report mentions two studies that the Army conducted to determine the effectiveness of specific helmet designs and give real-world credibility to engineers’ research, development and laboratory testing.

Lack of regulatory oversight in the production of civil pilot helmets allow for low-quality products in the market, such as this split ear piece (above, left). A member of the quality-control team at Gentex Corp. randomly pulls a helmet off the line for lot testing and inspections (above, right). Photos courtesy of Gentex Corp. and Helicopter Helmet, LLC.
The first study, in 1961, examined helicopter accidents between 1957 and 1960 to determine the effectiveness of the Army’s Aircrew Protective Helmet (APH-5), which the service adopted in 1958 for its helicopter pilots. The report found that fatal head injuries were “2.4 times more common among unhelmeted occupants of potentially survivable helicopter accidents than among helmet-wearing occupants.”

The second study, in 1991, examined helicopter accidents between 1972 and 1988 involving the Army’s newer Sound Protective Helmet (SPH-4) design. Again, the study found the helmet invaluable. Occupants without helmets were found to be 6.3 times more likely to experience fatal head injuries than those with helmets. For those riding in the back of the helicopter, risks increased 7.5 times. The Army lab said this was “particularly relevant because civilian flight medical personnel generally ride in the rear of the helicopter.”

A Confusing Market

Could military crash studies benefit the commercial sector? Though the Army lab’s report noted that the 1961 and 1991 studies focused on strictly military missions and equipment and questioned their applicability to commercial operations, it said that, “since civil aviation injury data are lacking, it does appear reasonable to apply these military data to civilian helicopter scenarios with similar flight profiles.”

The good news is that since the U.S. government owns military helmet specifications (documents that specify the materials, design, construction, testing standards and packaging of a helmet), they are typically available in the public domain. Many of the newer commercial helmets on the market today, such as Gentex Corp.’s HGU-56/P, are based on U.S. military specifications.

But unlike the military, the commercial sector lacks a central authority to certify new helmets. This results in a confusing maze for consumers to navigate, and a market that even the manufacturers themselves admit is full of problems—such as counterfeit and copycat products, dubious testing practices and deceptive advertising.

According to Mark Jones, a senior product specialist with Carbondale, Pennsylvania-based Gentex, “There are quite a number of reproduction pieces that look just like Gentex on the market, and they’re of much lower quality.” Jones explained that some are obsolete parts reintroduced through government surplus, while others are actual copies falsely marketed under the Gentex brand—a repeated occurrence that has prompted legal action from the company.

A lack of regulatory oversight also means manufacturers can adopt very different testing processes. With the hopes of minimizing any bias and conveying transparency to his customers, Ron Abbott of Johns Island, South Carolina-based Helicopter Helmet, LLC said he sends his products to a neutral external testing facility, Dynamic Research, Inc. Some manufacturers said they test and certify their helmets in-house but allow customers to make unscheduled visits to test helmets right off the production line.

Additionally, not all specifications are created equal, and that fact is hardly transparent. For example, MIL-DTL-87174A is a U.S. Air Force specification for helmets withstanding buffeting, turbulence and ejection from a fighter cockpit, not the heavier impacts common in helicopter crashes. MIL-H-43925D is the specification for the SPH-4D, the helicopter pilot helmet that the Army has retired in favor of the HGU-56/P. Helmets built to any of these specifications might be sold today on the commercial market, and buyers unfamiliar with helmet design might not completely understand the differences and instead choose a product based on its weight or aesthetic appeal rather than its protectiveness.

Although manufacturers like Gentex and Helicopterhelmets.com might differ on the way they do business, they seem to agree at least that a centralized testing and certification body would help alleviate the turmoil.

“The biggest challenge is probably that there are no national or even state standards for impact protection of helmets,” said Jones. “When you don’t have that, you open the door for cut-rate products to make their way into the market.”

Abbott said a solution would be to have “somebody set a standard, and set one testing facility to do the helmets.” An organization like the American National Standards Institute would suffice, he added, but only if all helmet manufacturers submitted their products to the same testing facility because “we all know that we can manipulate any kind of test.”

An Example to Follow

Perhaps the most ideal candidate to serve as a neutral certification body is the Army Aviation Research Lab. While it theoretically has the knowledge and equipment necessary, it might not have the bandwidth to serve an entire commercial market, and the lab’s mission “does not include performing quality control on the commercial marketplace,” said Joe McEntire, a research mechanical engineer with the lab’s Injury Biomechanics Division. However, he added, “USAARL staff members do actively participate on many industry standard committees and would consider participation in an effort focused on the commercial marketplace.”

The Snell Memorial Foundation offers another model for how the rotorcraft industry could improve helmet quality across the board. The grant-funded nonprofit offers motorcycle helmet manufacturers an optional but respected certification that it said exceeds regulatory standards set by the Federal Motor Vehicle Safety Standards—by which the Department of Transportation “establishes minimum performance requirements for helmets designed for use by motorcyclists and other motor vehicle users.” To apply for Snell certification, a manufacturer must submit its helmet designs for testing in the organization’s laboratory. If a helmet passes Snell’s requirements, the manufacturer enters a contract specifying what it must do to maintain certification and agrees to let Snell collect periodic samples from its production line for additional testing.

The manufacturer covers all costs, such as testing and licensing fees, but the whole process, according to Johnson, “is probably one of the cheapest in the world.” Thanks to Snell’s nonprofit status, average total costs amount to $1.25 per helmet tested. Snell, in turn, is funded primarily with grants from government bodies—usually federal or county departments implementing their own safety programs—and it refuses donations from manufacturers to avoid any conflict of interest. None of its employees, including its board of directors, are allowed to hold interest in any helmet company. But Snell does collaborate with manufacturers to do research on the latest design innovations and to improve its own ever-increasing certification requirements.

Helmets are tested on a drop tower at high velocities for impact. Photos courtesy of Gentex Corp.
The Snell certification process is not without criticism. (According to a Sept. 2009 New York Times article titled “Sorting Out Differences in Helmet Safety Standards,” some scientists have criticized Snell’s growing standards as a marketing gimmick, saying they don’t necessarily make for a safer helmet.) Whatever the truth of the matter, a rotorcraft industry equivalent could still adopt Snell’s basic model, deciding what quality standards to set based on data it collects from the industry, and offer a central facility at which to test incoming helmets.

James Wegge, owner of Gentex distribtor Gibson & Barnes, said he believes that just such a system could work in the rotorcraft industry if it were formed by relatively neutral organizations, such as the Airborne Law Enforcement Assn., Assn, of Air Medical Services, Air Medical Operators Assn., the Commission on Accreditation of Medical Transport Systems and Helicopters Assn. International.

“The idea is it’s a voluntary board made up of delegates from the user associations who would then examine the factors and decide whether to certify a helmet,” said Wegge. The board would collectively set criteria for things like written specifications, engineering drawings, quality assurance programs and configuration control systems. “The manufacturers would submit their helmets voluntarily, and if the board approved them, they would grant a certification.”

This, in turn, could become a model for other countries whose regulatory environment is similar to that in the U.S. For example, like the FAA, Transport Canada has not required the commercial use of helmets or established helmet quality standards. Organizations such as the Helicopter Assn. of Canada are pushing for the voluntary use of helmets by Canadian pilots and might benefit from a similar process.

Wegge has proposed the notion to various organizations and said he he can get them to buy in. In the meantime, if pilots want to know how to choose a good helmet in the U.S. market, he said, “It depends on who they trust.”

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