MOTOR SPEEDS

Hokitika Guardian, 26 May 1930, Page 2

MOTOR SPEEDS

CHANGE IN METHOD OF ESTIMATION.

A JUDGE’S SUGGESTION

AVELLINGTON, Alay 22,

The. opinion that there would be a great diminution in the number ot motor accidents if drivers were to estimate their speed in feet per second instead of in miles per hour was expressed by his Honour Mr Justice Blair to-day, when giving judgement in tlie Supreme Court in a.n action for damages. • “Although not relevant to the decision which 1 have just gi\on,” said his 'Honour, “the frequency of motor accidents justifies me ill attempting to add something o.'i the subject of ear© in handling motor vehicles which perhaps, may. help in reducing the number of motor accidents', it is to be noted that in this case, its in motor cases generally, til© evidence as to was given hi miles per hour, and a great many people, experienced motorists at -that, look upon miles per hour as affording a proper judication of speed. “An entirely false idea of speed and safety is -present' when a timer is content to think of. speed in terms oi miles por hour."' it is so easy to accustom oneself "to drive in feet per second instead of miles per hour that there js no reason why every motorist and motor-cyclist should not do it. Indeed, there is something to be said for the proposition that Until a driver can automatically ■ convert miles per atmr into feet per second he is not as efficient as he should be, The simple mental process necessary for this conversion is to add 50 per cent, to the miles’ par hour and tlie result is speed per isecoud, correct within 2 per cent. In a’ crowded city street 15 miles per hour may seem reasonable and sale, but its equivalent, 23 feet per second, puts the spaed into a different category' and calls for and, I believe, secures added caution. Afany accidents occur oil country roads due to plunging- over banks at corners or narrow places. Many of these would be avoided if the driver had a due appreciation of his speed in feet per second. If a cornbr be rounded t-t, say'2o miles per hour (30 feet per second) and the )"oad : bo narrow, one half-second only is sufficient for that car to move 1J'I’feet 1 ’feet in- the- wrong direction.” •

“There have 'been"from time to time published' tallies’, showing the distance- within whicii" efficient' brakes can bring a vehicle to a standstill. Ono table I have before me says that at 20 miles per hour a car equipped with efficient fb'ur-wheeled brakes can be;.pulled up in"‘io feet. ' There is a tendency to rely too much bn brakes, and in all these'-’ tables the fact is overlooked that 1 ' ’allbWalibb niust be made for the riietttal reaction necessary before the motorist has his brakes full on," ' “Alost authorities agree that one half-second allowance at Jeast must be assumed for mental reaction.” concluded his Honour.' "Applying _ this to the case of the perfectly equipped vehicle at 20 miles per hour it means that at that speed’ls''feet is travelled before the brakes are on, and it is another 25 feet -before the vehicle is stationary, 40 feet in all, This again illustrates tho wisdom of an appreciaton of speed iff feet per second.”