FAA Preliminary Comments - Airwolf Aerospace

October 10, 2024

Brian Hanley

Aviation Safety Engineer

Aircraft Certification Service

Federal Aviation Administration

1801 S. Airport Road

Wichita, KS 67209-2173

 

RE: Docket No. FAA-2024-2319

Project Identifier: AD-2024-00498-R Preliminary Comments

 

Dear Mr. Hanley:

The undersigned represents the company that designed and produced the tension torsion (TT) straps against which this emergency airworthiness directive (emergency AD) has been issued.

There is no substantive information in the docket that allows a comprehensive response. The information that is contained in the docket is incomplete and misleading. The accident referenced did not happen in the United States. The accident took place in Canada and is under that nation’s aviation safety investigation agency. That agency has not reached a conclusion, nor has it scheduled a date for its report.

We request the docket be supplemented immediately with the data required by the agency’s procedures governing the issuance of airworthiness directives. The information requested includes, but is not limited to:

Until the agency provides the information essential to compliance with the Administrative Procedure Act, we request the agency withdraw the immediate effectivity of the action and replace it with a normal notice of proposed rulemaking.

To establish that the current proposal does not rise to the level required to issue an emergency action, each pertinent element of the Final Rule is addressed below. The agency’s information is depicted in italics, the company’s comments are in bold.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for Bell Textron Inc. Model 204B, 205A, 205A-1, 205B, 210, and 212 helicopters and various restricted category helicopters with certain part-numbered tension torsion (TT) straps installed by supplemental type certificate (STC) No. SR03408CH. This AD was prompted by an accident involving failure of a TT strap. This AD requires removing the specified part-numbered TT straps from service and prohibits installing those TT straps. The FAA is issuing this AD to address the unsafe condition on these products.

The agency must make more than statements; it must provide a reasonable nexus between its independent determination of the accident’s probable cause, and any contributing factors, to the unsafe condition.

There is absolutely no evidence in the docket of the agency’s investigation of the accident or the failure of the TT strap. The agency’s process demands an independent evaluation of safety information pertinent to the accident, and thus the failure of the TT strap, including the operating conditions, aircraft history and usage, other design, manufacturing, operational, or maintenance conditions or information upon which decisions can be or were made.

In addition, the agency procedures specifically encourage communications to obtain information that resolves questions of substance. Rather the agency reached its conclusion and issued an emergency action on “indications” and “possible” failure modes noted during an on-going investigation of the Canadian government.

It did not contact us, the design and production approval holder for the strap, although it is rumored that the agency did involve the type certificate holder of the aircraft and other interested parties. No information or conversations that may have taken place regarding the accident or the agency’s actions against the TT strap are in the docket. If any conversations took place, the failure to thatinclude information in the public docket is a blatant disregard of the law regarding ex parte communications during informal rulemaking.

The agency must provide the report and data on its independent analysis of the alleged unsafe condition. The docket does not contain the FAA’s Airworthiness Concern Sheet (ACS), or any other pertinent information.

Background

This AD was prompted by an accident involving a Bell Textron Inc. Model 212 helicopter, which experienced a separation of a main rotor blade from the main rotor head and subsequent impact into terrain shortly after takeoff. Initial investigation determined the TT strap failed at 664 total hours time-in-service (TIS).

The agency fails to mention that the accident happened in Canada; an omission that is vital to obtaining the technical information necessary to make an independent determination of the impact on the U.S. fleet. The Transportation Safety Board of Canada is conducting the initial and ongoing investigation. It has scheduled no date for the release of its report.

Investigations into individual wire failure mechanisms are ongoing with early indications suggesting some wires possibly failed in tensile overload and others in fatigue. Bell Textron Inc. Model 204B, 205A, 205A-1, 205B, and 210 helicopters and various restricted category helicopters are also affected by this unsafe condition since the affected TT straps may also be installed on these model helicopters.

Early indications are often proven misdirected; the company is intimately familiar with the materials used and has performed numerous tests of its articles. Through the material and article testing and evaluations, it has developed expertise in potential individual wire failures and mechanics, yet it was not given the opportunity to provide any information to the FAA regarding “possible” failures due to overload or fatigue. There is no mention of other potential failures or contributing factors. There is no evidence of the technical evaluation that ledto the tentatively worded conclusion that the strap’s failure required an emergency AD.

The company can only assume the agency is reaching its conclusion based upon the investigation being conducted by the Canadian authority. The company was not allowed to be a party to that investigation but has provided technical knowledge when requested.

Transport Canada has issued a safety alert that contains more information than the FAA’s emergency AD docket. That safety agency alert strongly recommends the straps be inspected at the earliest opportunity, a proactive approach that “can help identify the root cause of any failure modes that may be present.”

This condition, if not addressed, could result in loss of a main rotor blade and subsequent loss of control of the helicopter. The FAA is issuing this AD to address the unsafe condition on these products.

FAA's Determination

The FAA is issuing this AD because the agency determined the unsafe condition described previously is likely to exist or develop in other products of the same type designs.

The agency must provide the information upon which it draws its conclusion. It may not merely make pronouncements. It must give interested parties an opportunity to provide substantive comment by including at least the minimum information required by its own procedures that ensure the agency complies with the laws applicable to informal rulemaking.

Justification for Immediate Adoption and Determination of the Effective Date

Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 et seq.) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for “good cause,” finds that those procedures are “impracticable, unnecessary, or contrary to the public interest.” Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause.

An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this rule because an affected TT strap was involved in an accident in which the TT strap failed, resulting in the main rotor blade detaching from the main rotor head. Failure of an affected TT strap could occur at any time without any previous indications and result in a sudden and catastrophic condition. Thus, an urgent unsafe condition exists and the required actions must be done within 50 hours TIS, a time period of up to two months based on the average flight-hour utilization rates of these helicopters. However, a significant portion of these helicopters in the U.S. fleet are high usage helicopters, which have an increased likelihood of occurrence of a failure and will reach the compliance time within a period of approximately one week based on the average flight-hour utilization rates of these helicopters. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b).

In addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forgo notice and comment.

The agency guidance which ensures it complies with the statute cited statessevere conditions for issuance of an emergency action, for example—

The failure of agency personnel to be efficient or responsible by exercising diligence in processing a rulemaking is not, in itself, anappropriate reason to use a good cause exception.

* *  *

Notice would be “impracticable” if immediate action must be taken because safety could be compromised during the time it would take to comply with “Notice and Comment” requirements.

There is no indication other than the agency’s blanket statements that there is such an urgent need for the removal of the articles. Since the Canadian Safety Alert, there have been no Service Difficulty Reports (SDRs) submitted regarding the TT straps at issue in the AD. There are no SDRs on the subject straps in the United States reporting system.

The investigating authority has not reached a conclusion as to the exact nature of the failure, yet the FAA has concluded without providing any supporting facts or technical analysis, that immediate action is necessary.

The following circumstances require the withdrawal of the action and the issuance of a safety bulletin requiring first opportunity inspections like the Canadian alert—

To support our request, we submit the following additional information:

The HAC statement in its publication the day that the AD was issued boldly announced:

"The Helicopter Association of Canada (HAC) received advance notice of the AD and said in a message to its members on Sept. 25 there had been ‘no indication that an AD is forthcoming from the FAA that will impact other TT straps made by this supplier.’

Thank you in advance for immediate action.

 

John P. Kochy

President

Airwolf Aerospace LLC

cc: The Honorable David Joyce

Laura Megan-Posch