FORT RUCKER, Ala. (August 3, 2017) - It was back in the summer of 2000 and I hadn't yet gone to flight school. At the time, I was serving as a flight engineer on a CH-47D Chinook. Our mission was a simple, routine night vision goggle flight with a couple of very experienced pilots on the controls. During the brief, the pilot in command said he wanted to focus on slingload training and told me it was my night in the cargo hole.During the startup, we confirmed all the hooks were operational and I prepared the cargo hole for slingload operations. As the flight progressed, everything seemed to be going smoothly and according to plan. Prior to beginning our slingload iterations, the PC landed next to the load and I readied myself in the cargo hole as the other flight engineer inspected the load. I reviewed my setup to ensure I wouldn't have any issues during the hookup, and the PC briefed the crew on slingload operations.As we began to hover, I took my position in the cargo hole and called the aircraft over the load. With two experienced pilots flying the aircraft, the hookup went well. Since we were doing multiple iterations, we typically hooked up a load, came to a hover, placed the load on the ground, repositioned and did it all over again (aka "elevators"). Everything was going as planned. What could go wrong with something that's so simple and routine?During the last iteration, the PC hovered over the load and, like each time before that evening, the hookup went smoothly. Then something different happened. As we were hovering with the load, the pilots began discussing techniques and failed to notice the aircraft had begun to settle and the load was back on the ground. I notified the pilot, but received no response.As the Chinook began to drift, I noticed we were dragging the load. This went on for a minute or so with the load bobbing up and down and, from time to time, dragging across the ground. Finally, I announced the load was still hooked up and we were dragging it. The PC immediately released the load while the slings were still tight. Before I knew what had happened, I heard a loud bang and saw the center cargo hook fly into the cabin, bounce off the floor and fly back out. Luckily, I did something right that night and was positioned clear of the hook, saving myself the pain of getting whacked in the face. During the debrief, we determined the PC thought he had released the load after setting it on the ground. For my part, I'd assumed he knew what was going on 30 feet behind him.On this night, I let complacency and poor crew coordination win over my better judgment. I assumed because the PC was experienced that he knew what he was doing. Because of that, I let my complacency interfere with good crew coordination. I should have challenged the PC for a response as soon as I noticed the load was being dragged and not let it continue. Had I done that, I could have avoided the frightening end to that night's flight.Knowledge magazine is always looking for contributing authors to provide ground, aviation, driving and off-duty safety articles. Don't let the fact that you've never written an article for publication scare you. Our editors promise to make you look good. By sharing your knowledge, you can make a valuable contribution to those who need your information to do their jobs safely. Your article might just save another Soldier's life. To learn more, visit https://safety.army.mil/MEDIA/Knowledge/TellYourStory.aspx.