A) Aptera uses about 60% less energy, generating about 60% less heat, so air cooling may work as well for it as liquid cooling does in other EVs with 60% more heat.
B) In a crash, a traditional radiator can also be damaged.
regarding A: I guess if you want to use Aptera as a racing car (as mentioned in the video) you have to handle a lot of heat anyway. The heat dissipation has to be designed to handle power peaks. The limiting factor of skin cooling may be the surface used for cooling and based on the design you can use only the belly for this. A cooling system using a fan is very simple in this case. You only have to speed up the fan.
regarding B: I think a centralised cooling is better protected as "the skin" witch is likely to be damaged quite often (depending of the area). In this case you have also to think about the liquid polluting the environment.
@taubmann You always have to think about the liquid polluting the environment. My Fiat 500 BEV uses the exact same coolant as as a Fiat 500 ICE.
The most delicate part of a traditional cooling system isn't centralized, it's the front-mounted radiator. The belly location you mention for Aptera IS centralized, & as you note, that's better protected...:
The belly is less likely to be punctured if you rear-end someone, or if you're rear-ended & pushed into the car ahead of you. If you're sideswiped, the belly is still likely to be okay, especially in an Aptera where it's maybe 50-50 that the front wheel &/or highly-bulging door will take the brunt of the damage.
Racing an Aptera, will still create about 60% less heat than racing any other EV that's burning about 60% more energy per mile. Rad fans do little to nothing at speed.
Every car is different, but my own BEV's rad fans only come on for a few minutes if it's over about 95F & I plug into 6.6kW L2 right when I stop & there's NO airflow. Aptera is leaning towards only HALF that heat-creating current (3.3kW), so it would likely be fine, but worst case scenario would probably only have software delay or slow down charging for a few minutes while it cools down.
EDIT: One more factor I forgot. Even with no rad fan (due to having only a radiant belly) liquid coolant can easily be chilled by the A/C fluid, even below ambient temperature, which no radiator can do on its own, even with fans. My BEV's battery coolant has A/C-chilling capacity, but it has never come on, even driving hard & then plugging straight into 6.6kW at 113F ambient.
A) Aptera uses about 60% less energy, generating about 60% less heat, so air cooling may work as well for it as liquid cooling does in other EVs with 60% more heat.
B) In a crash, a traditional radiator can also be damaged.