Two drivers were critically injured Monday afternoon in a head-on crash on Highway 56 North just south of Dibrell.Both Robert M. Hodges, 66, of McMinnville and Jerry H. Goff, 36, of Smithville, were airlifted from the scene of the crash by medical helicopters and flown to Vanderbilt University Medical Center in Nashville where they remain under treatment.According to Investigating Trooper Rodney Whiles, the wreck happened around 2:30 p.m. Monday on a straight stretch of Highway 56 (Smithville Highway) located about a half-mile south of Dibrell. Preliminary indications show that Hodges was driving a 2001 Mercury Grand Marquis, heading north (away from McMinnville) on Smithville Highway when he crossed the center-line of the two-lane highway without warning.Goff, who was traveling southbound (toward McMinnville), was unable to take evasive actions in his 2004 Dodge Dakota and was struck head-on. The impact crushed both driver compartments as the vehicles came to rest in the middle of the highway only a few feet from one another.