USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #20-0041

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Tatonduk Outfitters Limited, dba Everts Air Cargo

Individual Name: Robert Ragar

Location State: AR Country: US

View the Interpretation Document

Response text:

August 6, 2020

Robert Ragar
V.P. Contractual Business & Hazardous Materials
Tatonduk Outfitters Limited, dba Everts Air Cargo
5525 Airport Industrial Road
Fairbanks, AK  99709

Reference No. 20-0041

Dear Mr. Ragar:

This letter is in response to your May 11, 2020, email and subsequent telephone conversations requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the operation of research and testing equipment installed on an aircraft.  Specifically, you detail the following scenario and ask whether the operations are subject to the requirements of the HMR:

  • ZeroGravity Corporation operates parabolic flights that create micro gravity environments;
  • During some of these flights, ZeroGravity Corporation supports governmental and private needs for research and testing in a micro gravity environment;
  • On these flights, research and testing platforms are installed on the aircraft. Some of these platforms may contain various amounts of hazardous materials;
  • Prior to flight, these research and testing platforms comply with Engineering Orders, receive approval from the Federal Aviation Administration (FAA) Designated Engineering Representative, comply with FAA Engineering Data Approval Form 8110-3, and are inspected by Required Inspection Item prior to flight; and
  • After receiving satisfactory determinations, these research and testing platforms are deemed worthy for air transportation.

The answer is yes. When the research and testing equipment contain a hazardous material, unless excepted, they are subject to the HMR. The HMR does provide certain exceptions, including those for air transportation in part 175. For example, § 175.8 provides exceptions for operator equipment that is required aboard an aircraft in accordance with applicable airworthiness requirements and operating requirements. However, because the research and testing equipment is not required onboard the aircraft for the operational flight and airworthiness of the aircraft, it is not eligible for the exception. Additionally, § 175.9 provides exceptions for certain special aircraft operations when applicable FAA operator requirements have been met. However, based on the scenario provided in your request, it does not appear that the operations meet any of the special aircraft operations.

If a person cannot comply with the requirements of the HMR or wishes to perform a function that is not otherwise permitted under the HMR, a special permit would be required, in accordance with 49 CFR part 107, subpart B.

Please note that the HMR only applies to the transportation of hazardous materials. Therefore, the research and testing platforms must also comply with any additional air worthiness requirements, in accordance with 14 CFR.

I hope this information is helpful. Please contact us if we can be of further assistance.


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

107, 175, 175.8, 175.9

Regulation Sections

Section Subject
175.8 Exceptions for operator equipment and items of replacement
175.9 Special aircraft operations