Reproduced 3/3 times. A similar bug occurred with PhysX ([Link Removed])

Check the function: 

FVector FSimpleAerodynamicsSim::GetCombinedForces(float VelocityIn)

if the velocityIn is negative, the value should multiply -1. Then the vehicle will get correct aerodynamic resistance.  

Steps to Reproduce
  1. Create a new Vehicles template project
  2. Open SportsCar_Pawn
  3. In Components, click on Vehicles Movement Component
  4. In Details>Vehicle Setup, set drag coefficient to 300
  5. Compile & Save
  6. PIE in VehicleExampleMap (the default editor map for the template)
  7. Tap the S key to begin reversing

Actual Result: Car accelerates to mach speed, clipping through the bounds of the map

Expected Result: Car reverses slowly, as dictated by the high amount of drag. It should be similar to the Car's speed moving forward.

Have Comments or More Details?

There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-161413 in the post.

Login to Vote

ComponentUE - Simulation - Physics
Affects Versions5.
Target Fix5.2
Fix Commit23991344
Main Commit23992431
Release Commit23991344
CreatedAug 19, 2022
ResolvedFeb 3, 2023
UpdatedApr 28, 2023
View Jira Issue