It is estimated that, on average, 26,000 rear hatches, tailgates, and other back doors opened in light vehicle towaway crashes each year during the period 1988 to 1992. More than two-thirds of these openings occurred in hatchback cars, and, for simplicity, this report uses the term `rear hatches' for the rear doors of hatchback cars, stationwagons, sport utility vehicles, and vans. Other vehicles are outside the scope of this effort; in particular, the tailgates of pickup trucks are not considered here. An estimated 3.4 percent of rear hatches involces in towaway crashes opened during the crash; an opening rate higher than that for front doors (2.0 percent) or other side doors (1.2 percent) in the same vehicles. Of the light vehicle rear hatches that opened in towaway crashes, an estimated 42 percent opened in rollover crahses and 71 percent involved latch or hinge damage. Just over one percent (1.4 percent) of occupants in light vehicles with opened rear hatches were completely ejected through that opening, and an additional 11.1 percent were completely ejected by another route (including some ejected through rear hatch glazing). An estimated 6.6 percent of all complete ejections from towed vehicles equipped with rear hatches were through the rear hatch. This suggests that in 1991 and 1992, an average 147 occupant fatalities a year were completely ejected through rear hatches. Perhaps 6 to 14 children under ten years old are among the rear hatch ejectees each year, but available data are inadequate for reliable estimates by age.
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