29 C.F.R. § 1979.102 – Obligations and prohibited acts.

(a) No air carrier or contractor or subcontractor of an air carrier may discharge any employee or otherwise discriminate against any employee with respect to the employee's compensation, terms, conditions, or privileges of employment because the employee, or any person acting pursuant to the employee's request, engaged in any of the activities specified in paragraphs (b)(1) through (4) of this section.
(b) It is a violation of the Act for any air carrier or contractor or subcontractor of an air carrier to intimidate, threaten, restrain, coerce, blacklist, discharge or in any other manner discriminate against any employee because the employee has:
1. (1) Provided, caused to be provided, or is about to provide (with any knowledge of the employer) or cause to be provided to the air carrier or contractor or subcontractor of an air carrier or the Federal Government, information relating to any violation or alleged violation of any order, regulation, or standard of the Federal Aviation Administration or any other provision of Federal law relating to air carrier safety under subtitle VII of title 49 of the United States Code or under any other law of the United States;
2. (2) Filed, caused to be filed, or is about to file (with any knowledge of the employer) or cause to be filed a proceeding relating to any violation or alleged violation of any order, regulation, or standard of the Federal Aviation Administration or any other provision of Federal law relating to air carrier safety under subtitle VII of title 49 of the United States Code, or under any other law of the United States;
3. (3) Testified or is about to testify in such a proceeding; or
4. (4) Assisted or participated or is about to assist or participate in such a proceeding.
(c) This part shall have no application to any employee of an air carrier, contractor, or subcontractor who, acting without direction from an air carrier, contractor, or subcontractor (or such person's agent) deliberately causes a violation of any requirement relating to air carrier safety under Subtitle VII Aviation Programs of Title 49 of the United States Code or any other law of the United States.