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US Industry Anticipates Fuel System Rules

The FAA is weighing new proposals for partial retrofit of crash-resistant fuel systems as an effective safeguard against post-crash fires.

Twenty-three years after the FAA ordered crash-resistant fuel systems be included in new-design helicopters, the agency is weighing new proposals to encourage partial retrofits of crash-resistant fuel systems on new-production rotorcraft has an effective means of preventing injuries from post-crash fires.

The proposal, and from the Rotorcraft Occupant Protection Working Group, a subset of the FAA’s Aviation Rulemaking Advisory Committee (ARAC) that the agency created in November 2015 to identify feasible means of getting more of the 80% of the commercial helicopters flying in the U.S. today without crash-resistant fuel systems retrofitted with them.

The working group is made up of 19 representatives of helicopter manufacturers, vendors and trade associations, two observers from the European Aviation Safety Agency and one observer from the FAA. In a November 2016 interim report, the working group told the FAA that requiring retrofits on current-production helicopters of crash-resistant fuel systems that fully comply with 1994 standards would be cost-prohibitive. Current rules only require fully compliant systems on helicopters built to a type certificate issued after October 1994.

The FAA apparently was not happy with that answer. In January, it directed the working group to recommend what parts of the 1994 standards might be incorporated in new-production helicopters to reduce the risk of occupant injuries from post-crash fires in otherwise survivable accidents.

The group worked that problem and in a May 11 report told the ARAC that its analysis of accidents involving helicopters type certificated before the new standards took effect that included post-crash fires showed two key points. Those helicopters whose fuel systems partially complied with the 1994 crash-resistance standards “are equally effective at preventing post-crash fires and thermal injuries” to occupants and they “reduced the post-crash fire rate by 90 to 100% for fires due to fuel spillage in survivable accidents.”

NorthStar-operated Airbus Helicopters AS350 B3.Photo courtesy of Airbus

Based on its research, the working group recommended to the ARAC that the FAA adopt new rules requiring installation of components meeting some parts of the 1994 standards in what it called “newly manufactured legacy helicopters.”

Specifically, the working group suggested that the FAA require such helicopters to comply with drop-test requirements under Federal Aviation Regulations (FAR) Part 7.952(a)(1)(2)(3)(5)(6). It also called for such helicopters to comply with flexible fuel hose and breakaway fitting requirements of FAR 27.952(c) and basic mechanical design criteria of FAR 27.952(f). (The working group noted that the number of accidents involving post-crash fires with Part 29 helicopters was insufficient to draw valid conclusions, but it “cautiously” recommended that the new rules be applied to those larger aircraft.)

The ARAC is assessing which of those recommendations it may pass on to the FAA.

For nearly a decade, industry leaders and technical experts have been working off and on with the question on how to improve helicopter crash survivability. They’ve focused on, among other measures, strengthening airframes and improving private pilot training.

When the FAA formed the working group, the agency noted fatality rates from helicopter crashes had remained almost unchanged since the 1994 rulemaking. “If the occupant protection improvement rules are not incorporated in new-production helicopters, there will be no meaningful reduction in the number of fatalities in helicopter accidents,” the agency said in late 2015.

Most helicopters makers have taken at least some steps to incorporate crash-resistant fuel systems into some of their long-in-production models, which currently are not required to have them because of the grandfathering of their designs under older standards.

Still, the FAA estimates that only about 17% of U.S. commercial or private helicopters flying in the U.S. have fire-resistant fuel tanks. “At the current rate of replacement and under the current rules, I’ll be long gone before crash-resistant fuel systems are in a majority of the helicopters in operation,” Gant said. “If there’s no requirement for retrofit and you figure a low fleet turnover rate of 2 to 3% … that’s about 20-plus years before we really get these fuel tanks into a big share of the active fleet.”

But aviation safety officials, joined by industry leaders, are hoping to significantly increase the adoption rate of the technology.

To do that, they must address two separate issues — getting the technology included in all new copies of older, previously certified designs still in production and retrofitting most of the more than 4,000 older helicopters now in service without the equipment.

The grandfathering that allowed manufacturers with existing certified designs to continue producing copies of those designs without the systems was not unusual for the industry. Many manufacturers have taken steps to include the systems in some, or even all, of their in-production models, including some covered by the 1994 rulemaking’s grandfathering provisions.

Bell Helicopter, for one, said it hasn’t made a commercial helicopter without crash-resistant fuel systems since 1991. Some of them don’t count as being formally certified as compliant because when they were originally certified. All of its designs certified since 1980 have included units that were essentially modified versions of systems it had been installing on military helicopters previously, the OEM said.

Most current Airbus Helicopters twin-engine products also have such systems aboard, that OEM said. Some versions of its H125, previously called the AS350, have had it since 1977. But not all — sadly including the one involved in that July 2015 crash in Colorado. However, since the company’s North American assembly line moved to Mississippi in mid-2015, all H125s have been made with the systems, said Airbus.

Airbus also is working with subsidiary Vector Aerospace and Robertson Fuel Systems to certify and supply retrofit kits built by those two companies working together for various Airbus helicopter models.

Robinson Helicopter, manufacturer of some of the lowest-priced — and therefore popular — light helicopters on the market now has the fuel systems on board all three of its models. The R66, Robinson’s jet-powered model, has had it on board from the day of its introduction back in 2011. The older four-place, piston-powered R44 got its system in 2009.

And the even older, two-place R22 model got it in 2013.

“We clearly had a couple of accidents that were survivable, but for a fire,” said Kurt Robinson, Robinson CEO. “Nobody wants that to happen to their customers, or to their brand. That’s why we’ve had an engineer working on that problem since the mid-2000s.” The manufacturer now equips R66s, R44s and R22s with the systems.

The reality of post-crash, post-fire lawsuits is one motivating factor driving manufacturers to incorporate fire-resistant fuel systems. That’s especially true for a family-owned company like Robinson that lacks the kind of deep pockets that companies like Bell, Airbus and Sikorsky. But Kurt Robinson said there’s a more simple and direct reason for making the equipment change.

“Yes, it’s not good for business,” he said. “But more importantly, we’re human. We don’t want people hurt or killed. That’s why we’re working on it as fast as we can. It’s not something you can do overnight. That’s what liability lawyers don’t understand. They say ‘bladder tanks have been around since the ‘60s, but they don’t understand that they’re not easy to make, and to make them light enough and strong enough to work in a light helicopter.”

LA County Might Get More Fire Hawks

The Los Angeles County, California, Fire Department may acquire two additional, customized Sikorsky S-70i Firehawks.

The department had requested approval of the county Board of Supervisors for a $29.4 million deal to lease the aircraft to bolster Southern California’s firefighting and emergency response helicopter fleet. The agreement would give it the option to buy the aircraft after 10 years. “These new aircraft will provide upgraded operational capabilities to meet current and anticipated future mission requirements,” the department said in a July report to the board.

The department operates a fleet of three Sikorsky S70a Firehawks based on the UH-60L and modified by Air Methods. RWI