The forces applied through the steering column were measured during low speed rear-end crash tests with human subjects where the delta V ranged from 8.5 to 11.6 km/h. Control tests measured the steering column forces without occupant contact. Each occupant was subjected to at least one test where they were unaware at the time of impact, and one test where they were braced and aware of the impending collision.
Test results showed that, in the unaware tests, none of the subjects maintained a controlled grip on the steering wheel. All subjects reestablished a controlled grip on the steering wheel between approximately 0.5 and 2 seconds following impact. Results of the control test allowed for discrimination between the inertial loading from the steering wheel and the loading applied to the steering wheel by the upper extremities for unaware subjects during the initial tensile phase of the steering column loading. Compressive steering column loads from re-establishing a controlled grip on the steering wheel were not discernable; however compressive loads from flail contacts with the wheel were evident.
In the aware tests, all subjects maintained a controlled grip on the steering wheel during the event. Although it did not occur in every case, in general, the peak tensile and compressive loads in the steering column were higher for heavier subjects.
Based on these results, loss of steering wheel control would generally not be expected for an aware driver, but an unaware driver would likely lose the ability to control their vehicle following a rear-end collision of this magnitude for a period of time that would last from approximately 0.5 to 2 seconds.