Take it easy

Take it easy

48 CURRENT TOPICS. [J. F. I, T a k e It E a s y . - - ( S t o n e a n d Webster Bulletin Vol. 8, No. 3.) T o measure the hazard involved in driving...

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48

CURRENT TOPICS.

[J. F. I,

T a k e It E a s y . - - ( S t o n e a n d Webster Bulletin Vol. 8, No. 3.) T o measure the hazard involved in driving a t various speeds the Travelers Insurance C o m p a n y has developed the " d a n g e r u n i t " which is defined in stopping distance, roll over, vertical fall and turning radius. Under average conditions the distance an automobile moves after its driver has decided to m a k e an immediate stop varies as the square of its speed. A " d a n g e r u n i t " equals 35 to 40 feet of stopping distance. A car traveling at 25 miles per hour can be stopped in this distance, while in stopping from 5o miles per hour it will travel between I4O and 16o feet, the equivalent of four " d a n g e r units." N e a r l y one full danger unit is added when the speed of a car is increased from 45 to 50 miles per hour. In case of too sharp a turn a car will sometimes roll over once for each " d a n g e r u n i t " it carries. T h u s i t . m a y roll over once at 25 miles per hour, twice at 35, and perhaps nine times at 75. I t is well to r e m e m b e r t h a t only in the luckiest accident can the driver cling to the inside of the rolling car as it does its 3 turns at 45. Striking a solid object at 25 will do a car a b o u t the same d a m a g e as if it had been driven off a two s t o r y building. Encountering a stone wall at 50 will be just as serious as if it dropped from 4 X 2 stories, or 8 stories. W h e n Captain George Eyston was doing 300 miles per hour and more on the d r y salt beds of Utah, his engine was packing energy into his car with such industry t h a t it was adding one " d a n g e r u n i t " for each mile of increased speed. H a d he hit a solid stone wall he and his machine would h a v e been smashed as irreparably as if he had driven off a 3000 foot ledge into G r a n d Canyon. Each added " d a n g e r u n i t " caused the car to require a longer turning radius. T h u s a car can m a k e only ¼ as sharp a turn at 50 as at 25; 1/9 as sharp a turn at 75 as at 25. I t is because a car can be turned v e r y little at high speed t h a t m a n y serious accidents occur on curves and when passing. R. H. O.