Bilateral Changes Promise Faster TSO Approvals

By Staff Writer | November 1, 2015

 A Cypriot AgustaWestland AW139 departs the guided-missile destroyer USS Donald Cook during a joint search and rescue exercise Oct. 16-17 off the coast of Cyprus. CYPUSA-02/15 involved a simulated maritime accident that triggered activation of the Cyprus National SAR Plan NEARCHOS. The AW139 is assigned to the Cypriot Joint Rescue Coordination Center. SAR operations were conducted by helicopters of the Airforce Command/460 SAR Squadron and Cyprus’ Police Aviation Unit. Photo courtesy of the U.S. Navy/Mass Communications Specialist 3rd Class Mat Murch.

Newly revised international agreements should clear obstacles for manufacturers offering helicopter improvements to operators in the U.S., Canada and Europe.

Officials of the FAA and European Aviation Safety Agency and the FAA and Transport Canada signed separate pacts Sept. 15. They cover revisions to bilateral aviation safety agreements between the national pairs that address implementation procedures for safety rules and standards.


The pacts would enable one aviation regulator to use simplified procedures for approving use of equipment covered by another’s technical standard orders (TSOs). TSOs cover a wide variety of aircraft equipment that is not part of an airframe, engine or propeller.

Under the new rules, when EASA or Canada issues a TSO, the FAA will accept it, and vice versa. There are some exceptions. For instance, while the FAA certificates auxiliary power units under TSOs, EASA treats APUs as aircraft engines and issues type certificates for them. So EASA will not accept an APU TSO from the U.S.

“It’s a small step in trying to get full reciprocal approvals among the regulators, but an important one,” said one industry official who has observed pacts’ development closely. “It will set in motion processes for reciprocal acceptance of other approvals, like supplemental type certificates.”

The FAA-EASA deal, however, can’t go into effect until its approval is coordinated among the 28 member nations of the European Union, which has strict procedures for that process.

Historically, the bilateral aviation safety agreement have been one under which those regulators validate all design approvals issued by the other. This means that a manufacturer has to go through an entire certification process with the other regulator, whose engineering specialists conduct a review of the standards used to issue a TSO. They decide whether to apply those same standards or require additional certification work. They then issue an entirely separate TSO covering the same product. That adds no safety to the end product, only paperwork and time.

Once the processes are implemented, industry officials said, manufacturers will gain more predictable, streamlined, timely and lower-cost paths to bring TSO’d articles to market for customers in the U.S., Europe and Canada.

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