Performance Skill Standard:
Conditions of Performance:
- Given a typical tractor-trailer, a road, a route of travel, and traffic…
Statement of Work to be performed:
- … The driver will properly manage the space required for safe vehicle operation.
Performance Criteria:
- Select a lane offering the best mobility and least traffic interruption, in accordance with the law, to cause minimum interference to other vehicles.
- Assure a safe gap before changing lanes, passing other vehicles, merging, relative to crosswalks so as to minimize hazards to other road users.
- Position tractor-trailer appropriately before initiating and completing a turn so as to prevent other vehicles from passing on the wrong side and to minimize encroachment on other lanes.
- Maintain a following distance appropriate to traffic, road surface, visibility, and vehicle weight; maximize separation from traffic when vehicle is disabled.
- Avoid structures having inadequate overhead clearance.
Performance Elements and Assessment Criteria:
- Explain basic formula for determining safe following distance.
- Judge adequacy of gaps in traffic for passing, crossing traffic, entering traffic, and changing lanes.
- Use proper visual search techniques to determine and achieve appropriate space.
- Properly position vehicle for making all driving moves, and avoiding getting other drivers or pedestrians in the wrong spot.
- Judge clearance on all sides of truck in motion, especially above the trailer.
- Adjust following distances for loads and road conditions.
Braking Time
Distance Traveled per sec – 1.466 foot per MPH
Reaction / Perception Time .75 sec.
Brake Lag .5 sec
Deceleration Time depends on speed
Distance = Speed2/(30*f) where f is co-efficient of friction
Following Distance
7 Second Rule
Judging by Stationary Object