However , loss of control of either vehicle can have unpredictable effects and secondary crashes can dramatically increase the expected crash severity .
Severity is usually lower than a head - on collision , since it tends to be a glancing blow rather than a direct impact .
Loss of control of either vehicle can have unpredictable effects and secondary crashes can dramatically increase the expected crash severity .
Severity is usually lower than a head - on collision , since it tends to be a glancing blow rather than a direct impact .