# Forums

## Let's try guessing the drag coefficient of the Model X while we wait for it to come out

So we know the Model has a CD 0.24. The X is a little taller but the underside should be the same in regards to CD. I am guessing that it will be (perhaps to optimistic) listed with a CD of 0.29

vandacca | March 31, 2015

I thought it was a given that the CD for the Model-X would be better than for the Model-S. Therefore, the CD will be less than 0.24, probably around 0.22.

The Coefficient of Drag when applied to a surface area, determined how much air friction is acting on the vehicle. Therefore, you have to essentially multiple the CD to the amount of surface area to get the total amount of air friction.

Therefore, even though the Model-X has a lower CD than the Model-S, because it has a much higher surface area, the total air friction will likely be greater than the Model-S.

I hope that helps?

pvetesla | March 31, 2015

Zzzzzzzzzzzzzzzzz

I think it's more exciting watching paint dry or watching a pot of water start boiling.

Both or which can now be changed to. "Waiting for my MX to arrive"

vandacca | March 31, 2015

@pvetesla you will be Zzzzzz by the side of the road, with a dead battery, if the CD isn't low enough. ;)

pvetesla | March 31, 2015

No way. Have you seen that Russian video of an MS being towed behind a truck to charge the battery.

BTW...CD's are overrated. I prefer my 8 track.

georgehawley.fl.us | March 31, 2015

jjs | March 31, 2015

I'm with vandacca 0.22, then 0.21 when the detachable side mirrors are removed to leave only the built in cameras.

jjs | March 31, 2015

@pvetesla - You are clearly not an enginerd like so many of us. ;)

pvetesla | March 31, 2015

HAHA....I almost missed that.

EngiNERD. I can't wait to use that in conversation!