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More tests for anti-jack-knife devices—Swingler
Page 52
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EQUIPMENT that helped to prevent jack knifing had proved effective under test conditions, said Mr. Stephen Swingler, Parliamentary Secretary to the Ministry of Transport, in the Commons last week.
He referred in particular to load-sensitive valves—which adjusted the braking effort on an axle to suit the load on that axle—and other devices for preventing wheel-locking.
Mr. Swingler warned that all such devices still had to be more extensively tested over a long period and in the wide variety of conditions arising in normal operation. Operators and manufacturers were co-operating in arranging such tests.
Mr. Swingler noted that progress towards preventing jack-knifing had included securing greater compatibility of the braking of tractive unit and trailer by changes in the distribution of braking effort on the axle and by minimizing wheel-locking, particularly on the tractive unit rear axle.