2007 Jeep Wrangler Sahara 25 Mp/h Unbelted NHTSA Frontal Impact

[MrDerbius]

Oh god look at those poor wipers!

[scott14705]

holy shit id hate to be hit by that on the road .

[MrVac14]

like a rock

[RaudelSolis]

@MrVac14 now i do like jeep expecially the new jeep grand cherokee, but this is a 25 MPH test not much going on.

[imnottellinguwhy]

bet it still ran after that



[jctevere]

Why is there such little crumple zone deformation? I can't imagine that from 25 mph to 35mph there is that much of a difference.

[whattheheck1000]

@jctevere Jeeps are built very strongly. And at 35, there was quite a bit of difference, the whole front end of the Jeep was destroyed and there was about a foot of crumple, the Jeep would no longer be driveable. A 35 mph collision has nearly twice the energy as a 25 mph collision because velocity (speed) is squared:

Force = mass * speed squared

July 22, 2011 11:54 am

[CarPro1993]

@whattheheck1000

Thanks for that handy little formula! I'm going to write it down! Does speed have to be Miles or Kilometers? Same goes for mass? Pounds or Kilograms. Or is it just Lbs with Mp/h and Kg with Km/h?

[whattheheck1000]

@CarPro1993 Yup. Lbs with Mp/h and Kg with Km/h.

Example:

A 1992 Ford Escort hits a wall at 35 Mp/h.

Force = 2400 lbs * 35 mph squared

Force = 2400 * 1125

Force = 2.7 million units

July 22, 2011 12:04 pm

[CarPro1993]

@whattheheck1000

Impressive! Thanks!

[whattheheck1000]

@CarPro1993 You are very welcome! I don't know what you'd call the units, not pounds-force... let's just say units. Here's a website that provides the force in pounds and tons:

hyperphysics. phy-astr. gsu.edu /hbase/carcr. html

(take out the spaces, links can't be posted "straight up")

July 22, 2011 12:08 pm

[CarPro1993]

@whattheheck1000

That's a really nice site, I was able to calculate that my Audi for example is 3,500 Lbs and hits a solid wall at 35 Mp/h, it has an impact force of 71.1 tons.

[whattheheck1000]

@CarPro1993 If it stopped in a foot, yes. I forgot to say, you need to put in the crush distance in the "crash that stopped the car in a distance of" box just above where it shows the tons. Default crush distance is 1 foot / 0.3048 m.

For example, this Jeep is 4,000 lbs, hit a solid wall at 25 mph, and crushed in 6 inch or 0.5 feet. The force on the Jeep is 83.6 tons. Your Audi would take less force because it has "crumple zones" that sacrifice the front end for safety.

July 22, 2011 12:19 pm

[CarPro1993]

@whattheheck1000

Oh, I didn't notice that. I will keep that in mind next time I do a calculation.

[whattheheck1000]

@CarPro1993 Alrightyy then!

July 22, 2011 12:25 pm (HA, my birthday in PM)

[CarPro1993]

@whattheheck1000

Is your birthday today?

[whattheheck1000]

@CarPro1993 No, it's December 25, hence the 12:25.

July 22, 2011 12:36 pm

[dave11686]

Thanks!

[whattheheck1000]

I bet that thing's still driveable. There's hardly any damage.

July 22, 2011 12:29 am

[CarPro1993]

@whattheheck1000

It bent the front frame up some and shifted the windscreen (Broke it too), new bumper, bumper support. frame needs realigned, and airbags.

It could drive, but it could be a total loss.

[whattheheck1000]

@CarPro1993 I bet if the airbags hadn't gone off it wouldn't be totaled. Then again, the unbelted dummies would have experienced very high HIC and Chest G values. And that Jeep probably could never be restored to drive in perfect condition.

July 22, 2011 12:36 am