The driver-side small overlap front test was the downfall for the 2020 Ford Explorer and 2020 Lincoln Aviator, as both midsize SUVs failed to capture a prestigious safety award from the Insurance Institute for Highway Safety, the institute announced.

Both the redesigned Explorer and the all-new Aviator scored just an acceptable rating on the evaluation, but Top Safety Pick and Top Safety Pick+ status both require a good rating.

Automaker Ford had expected the Explorer to earn a good rating in the driver-side small overlap test and said it would investigate the shortcomings and implement changes with the aim of improving the vehicle's performance for a future test.

However, the midsize SUV did show some improvement in the test over earlier models, according to IIHS engineers.

Overall, the Explorer's structure held up well. This was a significant improvement over the severe intrusion seen in the Explorer prior to the redesign. Even so, in the test of the 2020 model, there was enough intrusion into the outboard part of the footwell to elevate the risk of injury to the driver's left leg, as indicated by measures taken from the dummy.

On the upside, both Ford vehicles garnered good ratings in four other crashworthiness evaluations including the moderate overlap front, side, roof strength, and head restraint tests.

What's more, both SUVs aced the front crash prevention category. Both the Explorer and Aviator are equipped with a standard vehicle-to-vehicle front crash prevention system that captured a superior rating — preventing collisions in 12 and 25 mph tests.

The two models got mixed marks for their headlights. While all Explorers built after June earn an acceptable headlight rating, the Aviator's static LED reflector base headlights rate just marginal. However, its available curve-adaptive headlights scored a good rating.