Page MenuHomeFeedback Tracker

HEMTT Truck slows down too much with one flat tire
Assigned, WishlistPublic


First of all: I didnt enter the Product version because i didnt know which one it was. But its the first beta release version (I guess it's 0.7'ish)

I figured if i flat or destroy one tire of the HEMTT truck, it slows down way too much. Of course I am no veicle expert, but my guess would be that a 8x8 vehicle with 2 double axis wouldnt bee too affected by one flat. It somehow feels like driving an Ifrit or Hunter with one flat.

What does the rest of you guys think about this?


Legacy ID
Game Physics
Steps To Reproduce
  1. shoot one tire of the HEMTT
  2. Get in the HEMTT
  3. Drive
  4. Compare driving behaviour to an Ifrit or Hunter with one flat

Event Timeline

Raahk edited Steps To Reproduce. (Show Details)Jun 22 2013, 10:22 PM
Raahk edited Additional Information. (Show Details)
Raahk set Category to Game Physics.
Raahk set Reproducibility to Always.
Raahk set Severity to None.
Raahk set Resolution to Open.
Raahk set Legacy ID to 2784088502.May 7 2016, 2:46 PM
Bohemia added a subscriber: Raahk.Jun 22 2013, 10:22 PM

no its the alpha dev build.

I edited it, thank you

Unknown Object (User) added a subscriber: Unknown Object (User).May 7 2016, 2:46 PM
Unknown Object (User) added a comment.Jun 22 2013, 11:48 PM

because you are comparing a truck with a car, you just dont compare them. i think this is on purpose

Dr Death, please try it out before downvoting. It's stupidly unrealistic at the moment.

b101uk added a subscriber: b101uk.May 7 2016, 2:46 PM

At the moment, you can destroy any 2 tyres on the same axle excepting the very front axle and can do ~ 83kph (~ 51mph) in turbo mode (fast rather than normal forward), if you destroy the two tyres on the very first axle you will do ~ 51kph (~ 31mph) in turbo mode.

You can destroy any 4 tyres provided you are still left with 1 tyre on each side for each principle bogie set (bogie, a set of closely spaced axles generally working in unison) meaning each axle could just have one tyre with two tyres total per side and can do ~ 51kph (~ 31mph) in turbo mode.

It is actually easer to drive IF you suffer a single tyre being destroyed if you stop, get-out and either go an destroy the corresponding tyre on the opposite side of the same axle excepting if it’s the very first axle, in which case go and destroy one of the other tyres on axle two, three or four on the opposite side as then you will do ~ 67kph (~ 42mph) in turbo mode.

So really the only issue as far as speed is the first axle has more of an effect than all the other axles.

The real problem is the disproportion of yawing if you lose one of the rear tyres, it acts just the same as if you had lost a front one at speed, when really on an 8x8, 8x6, 6x6 having a single REAR tyre have a catastrophic failing is rather a none-event unless you’re going at speed around a corner at maximum weight and it’s a tyre on the outside of the turn that goes, but then that more a risk of it falling over because of the sudden weight shift vectored to the outside of the turn rather than a loss of directional steering control or yawing.

Likewise you could also argue that the yawing that is appropriate for a front tyre failing is intrinsically backwards for a rear tyre failing, as in a fully loaded state, if say if one of the left rear tyres was to fail, then the left rear of the truck then becomes more prone to causing over-steer to the right at the same time the right front wheels are unloaded as the left rear has dropped, but as a general rule of thumb, a front steered tyre that deflates will pull to the same side it’s on, while a rear tyre will cause slip to the side it’s on thus promoting over steer to the opposite side.

Unknown Object (User) added a comment.Jun 23 2013, 4:00 AM


Raahk added a comment.Jun 23 2013, 3:11 PM

@b101uk: Thank you very much for your more detailed information about this issue. In my describings, i am very limited to my english which needs a lot of improvement. It just felt like the truck is too much dragged to one side with one destropyed tire. I am going to make some tests like you described.

@Dr_Death: Since i am no vehicle- and/or physics expert, i opened this thread to discuss this issue. It just didnt feel right, that a 400 horsepower with 8 wheels would be so much affected by one flat. Perhaps if you're going to reproduce what i wrote you see what i mean.

Exactly, Raahk.

Unknown Object (User) added a comment.Jun 23 2013, 10:12 PM

you see why 400 HP and 8 wheels have this problem?

1- low torque
2- high weight

That still doesn't prove that it's realistic.

I figured the same goes for the Strider and its Opfor counterpart

pops added a subscriber: pops.May 7 2016, 2:46 PM
pops added a comment.Jun 26 2013, 5:09 AM

I agree, a HEMTT with almost no load should be able to continue driving, with reduced handling maybe. As soon as load bears down on all axles it should be difficult to move. This shouldn't be too hard to achieve with PhysX.

Raahk added a comment.Jul 19 2013, 4:44 PM

I have to correct my last comment. I didnt meant the Strider (since it has only four wheels). What i actually meant was the Marid and the Marshall.
The Issue with the HEMMT seems fixed. Is that true?