MZ-3Z Airship (IMAGE) Naval Research Laboratory Caption A modified American Blimp Corporation A-170 series commercial blimp, the MZ-3A boasts a proud heritage and now serves as the only manned airship in the United States Navy's inventory. Credit Naval Research Laboratory Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.