MemberAugust 18, 2021 at 9:28 pm
I’m used to thinking about all an AWD vehicle being more stable on snow/ice. Would a 3-wheeled, AWD vehicle be similar? I’d like to take my Aptera to the local ski hill (Colorado). I’ve read that the AWD version is faster but I don’t really care about that. I’d love to save a little and not spend for this particular upgrade but wondering if I’d regret it on snowy drives. I understand that Aptera is working with other countries to create something that is good for cold weather but one has to wonder how much innate winter knowledge comes from a manufacturer in San Diego. (No offense, I like beaches too.)
MemberAugust 18, 2021 at 10:57 pm
Aptera will definitely handle better with all wheel drive on most icy conditions. Depending on how deep of snow you would also need the offroad package to give it the higher ground clearance/ stronger wheel covers. I’ve never driven a 3 wheel car befor and am concerned about the centered rear wheel not having much traction as it plows its own train in the center of the lane.
MemberAugust 18, 2021 at 10:57 pm
My understanding is yes, AWD for a 3-wheeler will be better on snow/ice. Which is the reason I’m going with it. Took me a half-dozen tries last winter in my Prius getting up the hill on the unpaved snowy road that my fiancée lives at the end of. Also plan on using this to get to hiking trailheads; often those are at the end of really terrible roads.
MemberAugust 19, 2021 at 4:24 am
3 wheel drive should have better control. I too am wondering about that mound of snow that can build up in the centre of the lanes of rarely plowed side streets and country roads.
I like the low ride look of the Aptera, the off road option not as much. It may end up being my 8 month car and I’ll keep my ICE as a winter beater like I used to do with my Mustang convertible.
MemberAugust 19, 2021 at 7:25 am
On the highway will it be able to operate with the rear motor only? FWD is subject to torque steer, RWD has better handling characteristics. You don’t need a lot of power when cruising on a highway, the Aptera in particular shouldn’t need much because of it’s low CD. Using the rear motor only when you don’t need lightning acceleration or to get our of a snow back should give you better handling and potentially better energy efficiency.
MemberAugust 19, 2021 at 9:10 am
No torque steer. In-wheel motors means no drive shafts. Torque steer comes from unequal length driveshafts. Also, you can’t just “turn off” an electric motor, although you can reduce it’s impedance or something like that to minimize drag. Not sure exactly how that’s done or works.
MemberAugust 19, 2021 at 9:29 am
You can turn off an electric motor depending on it’s type, permanent magnet vs induction. Tesla does it.
MemberAugust 19, 2021 at 10:01 am
Aptera does have torque control. From the FAQ:
How does Aptera handle in the snow and cold weather?
With all-wheel-drive and vectorized torque control, Aptera handles beautifully in the snow and ice. We are designing specifically for a lot of the cold countries that love electric vehicles. The Aptera will have a full climate control system capable down to -20 and up to 125 degrees Fahrenheit. With our sandwich core composites body offering great insulation and a nice heater, it’s very comfortable to drive in the winter.
MemberAugust 19, 2021 at 9:59 am
Why didn’t Aptera come up with a one wheel drive option for the rear? Acceleration would likely have been less than 10 seconds anyways, and likely better mileage too. Just me thinking. Any ideas?
MemberAugust 19, 2021 at 11:15 am
The obvious answer I would imagine is lack of stability with no torque vectored steering from the front wheels. I would not drive such a vehicle nor would such a vehicle pass safety testing
MemberAugust 20, 2021 at 7:15 pm
when braking weight transfers to front of car giving front tires most of the grip vs rear tires, so rolling resistance is needed most at front so motors and their regen braking is there. it may still pay back to have rear wheel drive only assuming driver brakes slowly enough almost all the time, so front brake caliper is bigger for in case braking needs to happen quicker.
MemberAugust 20, 2021 at 5:14 pm
I’m pretty concerned about winter highway driving on 3 wheels. Seems like a high probability of fishtailing in the inevitable mound of slush (or black ice), even with torque vectoring. But who knows, maybe torque vectoring is more effective than I expect??
The only 3-wheelers I see around here are weekend/3-season toys like Can Ams and Slingshots, whereas I’d want an Aptera specifically as a commuter. I suppose I could just work from home on those days….
MemberAugust 21, 2021 at 1:18 pm
I wouldn’t be thinking the worst for winter driving.
For those in markets where snow fall is a likely issue – basically north of the Mason-Dixon line – snowy roads are often graded, eliminating the excess accumulation of snow and ice in the center of the lane.
In more southern climes, when it snows there is no grading and the roads typically have two quasi-snow free tire lanes with the accumulation of snow in the center of the roadway.
In the two-wheel drive Aptera, the rear wheel in this instance is in a space where the surface is covered with the original accumulation plus what ever re-frozen slush has been deposited there from the other wheel paths.
Because mush of the accumulation has been either packed down or removed, the two front wheels will face lower rolling resistance than the single rear wheel which must plow through the center accumulation.
That rolling drag is situated in the center of rear of the Aptera and acts like an anchor you drag. The vectors in the two-wheel and all wheel configurations obviously would default to this ‘stable’ center-rear dynamic.
Fishtailing in this context is actually more likely in a four-wheeled rear-drive car because the essence of fishtailing is the desire of the rear wheels to overtake the fronts which is more likely if the rolling resistance of the rear-wheels is less than that of the the fronts.
You might experience a little fish-tailing in the Aptera when turning out of the well-worn paths in the snow while making a lane change or left/right turn. This would occur when the front wheels engage the mounds in the center of the road and the rear is in the ice of the path. It is then that stability control and torque vectoring may be employed to keep the Aptera stable.
In any case, the Aptera ought to be more stable than a four-wheeled car with rear drive and with stability control and torque vectoring, it ought to out perform a typical FWD four-wheeled car.
The Aptera’s range will take a bigger hit in the snow, though, as the rear wheel’s rolling resistance when driving on the center of the lane accumulation, is simply higher, adding greater drag to the equation. It may also ride a little rougher, depending on the consistency of the slush.
Also, if you want to keep physics for your friend, you should drive slower because, regardless of the vehicle, slick roads are slick meaning that you should always take extra care when driving in ice and snow.
That said, I would be less concered about driving an Aptera in snow or ice than I would any rear-drive car or pickup ever made.