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Making Sense of Restricted Category

Making sense of restricted category exerpt from Vertical Daily News

Posted on March 16, 2016 by Jason Colquhoun

Operators such as PJ Helicopters of Red Bluff, Calif., represent a new generation of utility operators making use of proven ex-military platforms in restricted category operations — in this case, using the Sikorsky UH-60 Black Hawk. Skip Robinson Photo.

The last few years have seen two storied military platforms — the Boeing CH-47D Chinook and Sikorsky UH-60 Black Hawk — make their first appearances in something other than military fatigues, as they began a new life of civilian work. The repurposing of military surplus aircraft is certainly nothing new, with the Black Hawk and Chinook following in the footsteps of aircraft including the Sikorsky CH-54, Hughes OH-6, Bell OH-58, and Bell UH-1 in finding life after the military.But what’s involved in taking an aircraft built for work in the Armed Forces and turning it into a civilian aircraft?

The first thing to note is that as soon as former military aircraft are sold to the public and enter the civilian world, they fall within the purview of the U.S. Federal Aviation Administration (FAA). The FAA has the authority to regulate them in accordance with Federal Aviation Regulations (FARs) and, if the aircraft are eligible, to certificate them as restricted category aircraft.

All ITAR (International Traffic in Arms Regulations) items such as military radios, electronics and weapons are removed prior to the sale. In order to obtain restricted category certification of a former military aircraft, the individual or company who will become the restricted category type certificate holder must prove, through a conformity procedure with the FAA, that the aircraft is in fact safe for the intended use or purpose. The certification basis for these aircraft must reference FAA approval documentation and the special purpose operation (or operations) for which it is being approved.

The applicant must establish maintenance and other compliance programs (commonly the manufacturer’s or the accepted military program), and once the aircraft is certificated in the restricted category, it will have a second data plate affixed next to the original military data plate, which will contain the name of the type certificate holder, aircraft model number, and a serial number. It is forbidden to change the name of the original model number. Once the aircraft is issued an airworthiness certificate (even a special airworthiness certificate in restricted category), the maintenance must be done in accordance with the requirements of Title 14 of the Code of Federal Regulations (CFR), part 43. What is a restricted category aircraft?

The topic of restricted category aircraft and their various operating limitations can be a somewhat confusing and contentious issue. The various regulations and requirements the FAA has established to govern this category of aircraft could fill a book, so we will aim to give just a cursory overview of the sea of information. But to understand why the regulations are the way they are, it helps to first look at how military aircraft were accepted for their original roles. Take, for example, the Bell OH-58 and UH-1; Bell Helicopter constructed each of these aircraft for military contracts and they are issued military certificates of airworthiness and military data plates.

The military is not, however, required to obtain FAA type certificates. The aircraft are accepted by conforming to the military contract requirements rather than FAA regulations.

In contrast, the civilian standard category near-equivalent version of the military surplus OH-58, the Bell 206, was manufactured under FAA regulations. Its maintenance and flight manuals are FAA-approved documents. Under FAA certification rules, many areas come under intense scrutiny, such as design and construction, powerplants, equipment, operating limitations, and instructions for continued airworthiness. The UH-1H or OH-58 and their associated military manuals were approved and accepted under contract with the manufacturer — but this did not include FAA approval. Military aircraft are also not subject to the restrictions of parts 27 and 29, so once they transition into their civilian life, the FAA takes the approach that additional measures of risk mitigation are in order.There are two primary reasons the FAA will award type certification in the restricted category: the aircraft is a U.S. military surplus aircraft being used in the commercial sector; or alterations have been made to a standard category aircraft that require it to be in the restricted category. (An example of the latter is aerial application spray booms and tanks mounted to a Bell 206, which not only place it in restricted category, but mean the aircraft will operate under the rules of part 137.)

The guidelines for the certification and operation of restricted category aircraft are established in the Code of Federal Regulations. (The FAA has also produced various supplementary documents, such as 8110.56A, to provide guidance on restricted category certification of military surplus platforms.) Part 21.25 says an applicant is entitled to a type certificate for an aircraft in the restricted category if it complies with the noise requirements of CFR part 36, and in the case of former military aircraft, is of a type that has been manufactured in accordance with the requirements of (and accepted for use by) an Armed Force of the United States — and has later been modified for a special purpose. These “special purpose” operations include agricultural, forest and wildlife conservation, aerial surveying, patrolling, weather control, aerial advertising, and “any other operation specified by the FAA.”

The operating restrictions are laid out in part 91.313. In short, it states that you can’t carry passengers or cargo for hire, and unless operating in accordance with the terms and conditions of a certificate of waiver or special operating limitations issued by the FAA, you can’t operate a restricted category civil aircraft in the U.S over densely populated areas, congested areas or airways, or near busy airports where passenger transport operations are being conducted. (This section does not apply to non-passenger carrying civil rotorcraft external load operations conducted under part 133.)

A challenging process

At this point, you may be wondering why anyone would venture into restricted category operations. In large part, it seems to be because these reliable aircraft can be procured for a reasonable price, and in the hands of good operators can be well maintained to FAA compliance standards and used highly effectively in the commercial market. And, in the case of the UH-60 and CH-47D, it’s not like the original equipment manufacturers are producing standard category versions of these aircraft. There are few production aircraft on the market that are focused on serving the utility sector, and these former military aircraft fit that role perfectly.

And. while the regulations for restricted category operations may be narrow, provisions do exist to allow operators to work more freely — particularly in part 133 (external load operations) via the use of “contingency plans.” Detailed within the Flight Standards Information Management System (8900.1, Vol.3, Chapter 51, Sec 6), this provision allows for a congested area to become an uncongested area by controlling site access, therefore allowing a restricted category helicopter to conduct external load operations.

Ken Krauss, of Blackhawk Helicopters in Southern California, operates a restricted category UH-1H, and has learned to navigate the often-murky waters surrounding the regulations. “First and foremost you have to understand the FARs and guidance materials better than the FAA — and to make things easier, I acquiesce to most FSDOs [flight standards district offices] by mobilizing my helicopter by truck and trailer to most job sites,” Krauss told Vertical. “This is a niche for me and allows me to do things I couldn’t do if I were to fly to a job site.”For instance, Krauss performs external load operations in busy downtown areas with his restricted category aircraft, often within Class B, C, and D airspace. He is able to do this by adhering to the governing FSDO congested area plans, which involve the securing of the job site via street closures and allowing only authorized personnel in the area.

Krauss said contact with local control towers is paramount. “Tower controllers don’t care whether the aircraft is restricted or standard category, they only care about traffic and separation.”

Other safety concerns, such as the emergency jettison of external cargo, and emergency landings without risking persons or property on the ground, are established and addressed. For instance, Kraus will trailer his UH-1H directly into the secured area and perform the lifts onsite, eliminating the need for ferrying, mitigating weather restrictions and times of arrival, and helping save costs — savings he can pass on to his customers.

“If I fly to a job, it’s because the jobsite is uncongested and is not considered densely populated, and I don’t need or require a ‘contingency plan’,” said Krauss. “It’s my determination that a jobsite is not congested or densely populated — I don’t need to ask an FSDO.”

According to Krauss, his experience has been that, to a large extent, most FSDO inspectors agree that the surplus military helicopter is a safe machine to operate, but they are hampered by FAA policy and the associated risk adversity. Compliance to regulation is the key to restricted category operational success, and ultimately, serious restrictions occur if operators opt to ignore them.

Interestingly, former military aircraft that are flown in the public use sector (such as CALFIRE’s fleet of modified military surplus UH-1H “Super Hueys”), are not subject to the regulation of the FAA when it comes to carrying passengers or operating over congested areas. It all comes down to liability, as public use is not under the authority of the FAA. In the civilian sector, to be classified for public use, the aircraft must be on a federal, state or local government contract for exclusive use for at least 90 days, and not be used to transport passengers or cargo for hire. Any people who are carried on-board must be mission essential personnel. Worth the effort

According to Travis Storro, an airframe and powerplant mechanic and FAA certification manger with Timberline Helicopters, some people seem to feel that restricted category aircraft are somehow less airworthy than their civilian counterparts — a line of thought that many restricted category operators feel is completely unwarranted. “If they are maintained professionally according to regulations, which include compliance with inspection requirements, airworthiness directives, service bulletins, and replacement of time-limited parts, they can be as safe as their civilian standard category counterparts,” he said. “It’s just that no manufacturer has spent millions of dollars proving the design to the FAA.”

Timberline is in the process of adding two UH-60s to its fleet, and Storro said he was hugely impressed with the aircraft. “These military aircraft were manufactured to outrageously strict safety specifications, which resulted in phenomenal engineering, such as self-sealing fuel tanks, high G-load crash survivability, and multiple system redundancies that were ahead of their time,” he said. “These aircraft have had highly successful service lives within the military with a proven safety record.”

With the U.S military beginning to auction off some of its aging fleet of CH-47Ds and UH-60s, companies such as PJ Helicopters and Timberline Helicopters are positioning themselves for future success with these highly capable aircraft. With a procurement cost of $500,000 to $800,000 for the UH-60s, and $2 million to $3.5 million for the CH-47Ds, the operators acquiring these aircraft are among the most well-established and highly-respected operators in the utility helicopter industry. These newly acquired aircraft will eventually be worth many times the initial investment. Through the complicated certification processes of restricted category, one thing is certain: there is a need for these utility aircraft. There are many first rate operators in the sector who get the job done safely, within the confines of proper judgment and FAA regulation, and it’s through their efforts that these legacy fleets of reliable aircraft are kept flying. If you see them in action in the public sector, stop and snap a photo or two with your newly acquired insight into the challenges of those who operate and maintain them. But please, just don’t ask the pilot for a ride! - See full article and pictures at:

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