Portable battery-powered megaphones.

Bibliographic Details
Corporate Author:	United States. Federal Aviation Administration
Format:	Government Document eBook
Language:	English
Published:	[Washington, D.C.] : Federal Aviation Administration, [1966]
Series:	Advisory circular ; AC no. 121-6
Subjects:	Megaphones > Certification > United States. Airplanes > Equipment and supplies > Certification > United States.
Online Access:	https://purl.fdlp.gov/GPO/LPS109796

Available Online