| Mike
Collins a former RoADA Chief Driving Examiner assembled the
following from experiments conducted by the Thames Valley
Police.
At an
airfield a vehicle was driven in a straight line and at a
given point the driver applied the brakes to 95% lock (the
most effective). The point P where the vehicle stopped was
marked. This exercise was repeated through varying speeds,
the driver applying the brakes at the same place each time,
and the final speeds at which the vehicle was traveling when
it reached the point P were measured and are given below.
Readers
may be surprised at some of the results measured. For example,
a vehicle which stopped at P when braked from 30 MPH was still
traveling at 11 MPH when braked from 32 MPH. |
|
| INITIAL
SPEED |
FINAL
SPEED |
| ASSUMING
VEHICLE STARTS BRAKING AT 30 MPH |
| 30
MPH |
0
MPH |
| 32
MPH |
11MPH
|
| 40
MPH |
26MPH
|
| 50
MPH |
40MPH
|
| ASSUMING
VEHICLE STARTS BRAKING AT 40 MPH |
| 40
MPH |
0MPH
|
| 50
MPH |
30MPH
|
| 60
MPH |
45
MPH |
| ASSUMING
VEHICLE STARTS BRAKING AT 50 MPH |
| 50
MPH |
0
MPH |
| 60
MPH |
33
MPH |
| 70
MPH |
49
MPH |
| ASSUMING
VEHICLE STARTS BRAKING AT 60 MPH |
| 60
MPH |
0MPH |
| 70
MPH |
36MPH
|
| 80
MPH |
53MPH
|
| ASSUMING
VEHICLE STARTS BRAKING AT 70 MPH |
| 70
MPH |
0
MPH |
| 80
MPH |
38
MPH |
| 90
MPH |
57
MPH |
| 100
MPH |
71
MPH |
|
