FORT RUCKER, Ala. (May 9, 2018) - I am an instructor with a 12B Combat Engineer MOS-T reclassification schoolhouse. As combat engineers, one of our main duties is utilizing military explosives. In fact, it is a graduation requirement for the students to attend a live-fire demolitions range, where they must prime and detonate certain military explosives. Sounds hazardous, right? Well, unfortunately for our schoolhouse, that wasn't the most dangerous event to happen to the cadre on this day.Because Camp Ravenna is not currently permitted to store military explosives in the ammunition supply point, we must travel roughly four hours to Camp Dawson, West Virginia, for the demolitions range. We make the trip in two chalks: advanced party drives light medium tactical vehicles, while the students use 15-passenger GSA vans. The chalks don't leave together because the vans can travel the actual speed limit; the LMTV's maximum speed is 55 mph.Prior to departure, we always have mechanics conduct a thorough preventive maintenance checks and services of all the vehicles, and this time was no different. Just as we were about to depart from Camp Ravenna, however, we were forced to make a last-minute vehicle change due to a mechanical failure. We were then on our way.The route to Camp Dawson is a rather easy drive. The vehicles get on two- to four-lane highways and basically just drive straight. We traveled this route for many years and everyone was familiar with it. This time, though, we were traveling later than normal due to the vehicle malfunction. This meant we would reach downtown Pittsburgh during rush hour.As we neared downtown, road congestion worsened. The convoy commander had briefed this, however, so all members knew what to expect. Traffic was stop-and-go, and all the vehicles in the convoy were traveling below the speed limit. Suddenly, a civilian vehicle merged onto the highway and did not yield to the lead LMTV. The LMTV's driver stomped on his brakes to avoid the merging vehicle. This created a chain reaction of LMTVs stopping suddenly.The driver of the third LMTV in the convoy, which was the replacement vehicle, locked up the brakes to avoid running into the vehicle in front of him. Unfortunately, that vehicle had not been driven for a lengthy period of time prior to this convoy, and the left side pulled harder than the right. This caused the LMTV to pull violently to the left. The driver turned the steering wheel to the right but overcorrected and lost control of the vehicle. The LMTV crashed through a guardrail and rolled five times down a 75-foot cliff.Thankfully, the vehicle occupants were wearing their restraints, and all items within the cab had been stored properly. Because they followed these preventive measures, these two Soldiers were able to walk away from this accident without injury. The LMTV was not as lucky and deemed too damaged to repair.Lessons learned - Although this story has a happy ending regarding the two Soldiers, there are some lessons we can learn from this accident. Firstly, no matter how much time is spent preparing for a mission, there will always be last-minute setbacks. Leaders have to ensure no one cuts corners to adhere to time restraints. Soldiers must conduct PMCS and proper maintenance on all primary and secondary vehicles to prevent mishaps such as this.Secondly, regardless of the safety measures taken and experience of the vehicle occupants, there will always be unforeseen hazards such as civilian drivers blindly merging into traffic. Drivers should do their best to see things before they happen in order to prevent them. Similarly to chess, Soldiers must think one or two moves ahead. It is our duty as warfighters in the U.S. Army to complete the mission; but it is also our duty to do so as safely as possible.Do you have a story to share? Knowledge is always looking for contributors to provide ground, aviation, driving (both private motor vehicle and motorcycle) and off-duty safety articles. Don't worry if you've never written an article for publication. Just write about what you know and our editorial staff will take care of the rest. Your story might just save another Soldier's life. To learn more, visit https://safety.army.mil/MEDIA/Knowledge/TellYourStory.aspx.