There are crash sensors to trigger air bags, pre-tension seatbelts, cut off the fuel pump and so on. You would think that some engineer must have thought about auto-unlocking doors!
The actual mechanism of how the door works as kind of "configurable deformation zone" usually involves somewhat thick steel rod running down the middle of the door that on hinge side abbuts similar strength member in the chasis and on the latch side connects to the latch. The latch has two distinct positions depending on whether the door is just latched or locked and the only latched position is not strong enough to hold the potential impact forces..
I’m having trouble finding more formal explanations for what you’re describing, though. I see a lot of talk about how the latching behavior links the door’s steel into the rest of the body, but very little about the structural aspects of the locks that link the handles to the latch’s release mechanism.
I’m the farthest thing from a car engineer, but I wonder if you’d know of anyplace I could read more about this structural aspect of locking design? Every time I accidentally lock out a passenger, I get frustrated: I’d find grace and patience easier to muster if I understood how someday it might save both our lives :)
[1] https://www.federalregister.gov/documents/2007/02/06/07-517/...
[2] http://www.autosafetyexpert.com/defect_doorlatch.php
[3] https://bestsellingcarsblog.com/2023/10/media-post-actuator-...
No, this is not the primary reason. The primary reason is safety from potential attack while in a confined, transitional space.
My late grandparents' Lincoln Mark VII non-LSC had autolocking doors when shifting into drive in 1988.
Automatic unlocking (Auto Unlock) All vehicle doors and the boot lid are automatically unlocked if one of the following conditions applies:
— In an accident, when airbags have triggered.
— Or: the electronic parking brake is engaged and the ignition is switched off.
—Or: the door release lever has been operated. This applies at speeds up to around 15 km/h(around 9 mph).