Airbag

Lore & Background

The airbag traces its origins to a 1919 United States patent submitted by two dentists from Birmingham, Arthur Parrott and Harold Round, for covering airplane and other vehicle parts. Air-filled bladders were in use as early as 1951. The airbag specifically for automobile use is credited independently to American John W. Hetrick, who filed for a patent on 5 August 1952, granted on 18 August 1953. German engineer Walter Linderer filed a patent on 6 October 1951, issued on 12 November 1953. Both Hetrick and Linderer proposed compressed air released by a spring, bumper contact, or by the driver. Later research in the 1960s showed compressed air could not inflate fast enough, leading to chemical and electrical airbags.

Reader's Guide

Airbags are considered passive restraints because no action by the occupant is required to activate them, unlike seat belts, which are active restraints. This terminology is distinct from active and passive safety: active safety systems prevent collisions (e.g., anti-lock brakes), while passive safety systems minimize effects once a collision occurs (e.g., seat belts and airbags). The airbag's significance lies in its role as a supplemental restraint system, working with seat belts to reduce injuries. Broad commercial adoption occurred in many markets during the late 1980s and early 1990s, following limited and sometimes fatal early designs in the 1970s. Modern airbags are triggered by crash sensors and an electronic controller unit that determines deployment based on collision type, angle, and severity.

Did You Know?

• The first airbag patent was filed in 1919 by two dentists for covering airplane parts.
• John W. Hetrick's 1952 airbag patent was inspired by his work with navy torpedoes and a desire to protect his family.
• Allen K. Breed invented a ball-in-tube crash sensor in 1967 that could inflate an airbag in under 30 milliseconds.
• General Motors marketed its first airbag modules under the name 'Air Cushion Restraint System' (ACRS) in the 1970s.