Sikorsky Testing
A technician sets up camera equipment to watch the rotor-blades on a Sikorsky YR-4B/HNS-1 helicopter in a wind tunnel at NASA’s Langley Research Center.
![9467664406_118cfed42d_o.jpg](https://th-thumbnailer.cdn-si-edu.com/lQvzpEZHodAjsml6YRVqJNebYKI=/1000x750/filters:no_upscale()/https://tf-cmsv2-smithsonianmag-media.s3.amazonaws.com/filer/65/e8/65e84224-1ccd-4591-8628-ca7f958f7575/9467664406_118cfed42d_o.jpg)
A technician sets up camera equipment to watch the rotor-blades on a Sikorsky YR-4B/HNS-1 helicopter in a wind tunnel at NASA’s Langley Research Center.