A: You'll need more than friction as other factors affecting rollover are loading, pre-roll maneuver (and possible movement of occupants), tire properties, terrain/roadway slope/etc will need to be considered to determine the speed at rollover.
- 1) Bus Accel/Decell from WATAI which may include weights, heights, etc
2) Next see the 21st ESV Conference A paper which may also include references to properties, etc STATUS OF NHTSA MOTORCOACH SAFETY PLAN by Aloke Prasad, David Sutula, Roger Saul, John Hinch, Charles Hott, Lawrence Valvo, Michael L. Sword, Paper Number: 09-0448
3) DOT also recently also came up with a Motorcoach Safety Plan which may include references on Motorcoach properties
4) NTSB reports involving Motorcoach rollovers as they include references to research/properties/etc
for example from NTSB Research Studies
Title: Selective Motorcoach Issues NTSB Report Number: SIR-99-01, adopted on 2/11/1999 Summary | PDF Document NTIS Report Number: PB99-917001