The Ford Mustang has standard driver and front passenger side knee airbags mounted low on the dashboard. These airbags helps prevent the driver and front passenger from sliding under their seatbelts or the main frontal airbags; this keeps them better positioned during a collision for maximum protection. Knee airbags also help keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The MX-5 Miata doesn’t offer knee airbags.
The Mustang has standard Post Collision Braking, which automatically apply the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The MX-5 Miata doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.
Both the Mustang and MX-5 Miata have rear cross-traffic warning, but the Mustang has Cross Traffic Braking (automatically applies the brakes) to better prevent a collision when backing near traffic. The MX-5 Miata’s Rear Cross Traffic Alert doesn’t automatically brake.
The Mustang’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The MX-5 Miata doesn’t offer a driver alert monitor.
Both the Mustang and the MX-5 Miata have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras and rear cross-path warning.
The Ford Mustang weighs 1092 to 1687 pounds more than the Mazda MX-5 Miata. The NHTSA advises that heavier cars are much safer in collisions than their significantly lighter counterparts. Crosswinds also affect lighter cars more.

