THE PASSING PROBLEM.

Auckland Star, Volume LXX, Issue 101, 2 May 1939, Page 16

THE PASSING PROBLEM.

DRIVING HABITS AND SPEED

]•:xpkiit's ous !•:u \.\ rions.

Observation of drivhig habits on highways points to the conclusion that many roatU* are too narrow to permit of fast travelling iilltomoliiles parsing each other witli an ample margin of safety. Unfortunately, accidents are not infrequent owing to pa->siug vehicles contacting, sometime* through an error of judgment on the part of the driver, and on some occasions through in-*uflicient road width providing a hazard to the approaching or passing motorist, who possibly may be travelling at a perfectly safe wpeed, except at the moment of passing another moving automobile.

In the United States the Bureau of Public Roads has lteen investigating this aspect of road safety, and has devised instrument* which record on a chart the H|M>ed of vehicles av. they pa-is other vehicle** on the highway, either singly or in groups, also the distance between vehicles before, while passing and at completion of passing.

The data thus obtained ; -> being sifted 'vith !i view to interpret in;; the effectiveness of the highway* in that country us a menus of modern transportation find nffording an iinnlvsis of the entire problem of vehicular movement and the practices of motor drivers in norimil highway traffic. So far the research of the bureau has ahown that there are four variables in each simple paisine. Three of them—the speed of the passed vehicle, the speed df the passing vehicle, and the speed of the approaching vehicle, if any—are independent variables, while the fourth, the dependent variable, is the distance required for the completion of the manoeuvre. Tn addition to these mnjor variables there are. particularly in multiple pausing*, a number of minor variables, many of which are significant in an analysis of the entire problem. It in hoped to discover, after a wide variety of driving conditions are automatically recorded on charts, that it is possible to determine whether the problem is one presented by the average driver or whether preeent highway design practices are creating entirely unnecessary problems, either impossible or extremely difficult of solution. It is this phase of the problem with which the American road authorities are most greatly concerned, and it is one that already calls for attention in thie country.