FLEET MANAG
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BY THE EDITOR
IT has been in my mind for many years that there is a need in transport circh for a conference at which directors, managers and engineers can get together an discuss matters relating particularly to their vehicles. So The Commercial Mot( is on September 24—the day before the Commercial Motor Show opens at Ear Court—to sponsor a one-day Fleet Management Conference in the Connaugl Rooms, London, one of the smartest and best-known venues in the capital. Thei will be four papers, details of which (together with the authors) are shown on the pages; I am flattered that the men concerned, all of whom are top experts, shoul so readily have agreed to contribute their knowledge. There is also, as can I seen, already an impressive list of other top men who have agreed to speak durir the conference; there are more names to come.
Further to add to this galaxy of names, I am delighted to announce that M Roger Gresham Cooke, C.B.E., M.P., president of the institute of Road Transpo Engineers, will be chairman of the conference. Mr. Gresham Cooke (a pre-w secretary of the British Road Federation) was from 1946 until his election 1 Parliament in 1955 as Conservative Member for Twickenham, Middlesex, direct( of the Society of Motor Manufacturers and Traders. A director of Rootes Ltd he is an acknowledged transport spokesman in the House of Commons, where I has long been a member of his party's transport committee.
1 am equally pleased, and honoured, that the president of the Traders Roo Transport Association has accepted an invitation to make the closing address.
With so many top transport names already on the list of speakers, the discussic periods on the four papers will undoubtedly be incisive, entertaining and ( inestimable value to the road transport industry.
All this, with lunch and cocktails, coffee and tea inclusive, makes 3 gns. p delegate a very modest reservation fee. I earnestly recommend you to make yol reservations early because accommodation will, genuinely, be kept to a limit so ; to ensure everybody's comfort and enjoyment. unit is appreciably more economical than the larger Leyland engine, whilst in terms of acceleration, performance and hill-climbing ability (with the same gearing in all cases) there is little to choose between the two power units.
The specification of this Scammell-coupling tractive unit follows conventional Albion lines. Like the four-cylinder version, it has a wheelbase of 7 ft. 8 in. whereas the fifth-wheelcoupling model has a wheelbase dimension of 7 ft, 10-5 in.; this, incidentally, being 7.5 in. less than the wheelbase of the four-cylinder fifth-wheel model. As with all medium-duty Albions, the basic five-speed constant-mesh gearbox is available with a sixth overdrive ratio at slightly extra cost, whilst the well-known Albion double-reduction driving axle is standard, without option.
Where the fourand six-cylinder models differ most, except with regard to Dower unit, is in their braking systems: the smaller-engined chassis has vacuum-assisted hydraulic brakes, whilst the newer six-cylinder design has air-hydraulic brakes, the airpressure actuator being of the Westinghouse diaphragmtype and not a servo in the true sense of the word. This means that there is no direct linkage between the brake pedal and the hydraulic master cylinder; but it does result in appreciably reduced stopping distances when compared with the vacuum-hydraulic-braked vehicle, my tests showily:, a reduction of 10 ft. in the braking distance from 30 m.pl.
With a kerb weight of 3 tons 12 cwt., the tractive unit, which had the 7.712-to-1 axle, was tested in conjunction with a Scammell 25-ft flat-platform semi-trailer, which weighed 2 tons 3.25 cwt. The imposed test load totalled 11 tons 18.25 cwt., and with myself and an Albion experimental engineer aboard the gross train weight was 17 tons 17 cwt.—which is only 2 cwt. above the manufacturer's recommended rating. Because the centreline of the turntable was only 4 in. ahead of the driving-axle centreline, the semi-trailer axle was carrying 2 tons 14.75 cwt. more than the driving axle, whilst the front-axle loading was a mere 2 tons 17.25 cwt., which is only 6 cwt. more than its loading in the unladen condition.
Slight fierceness was encountered when making the braking tests from 30 m.p.h., whilst locking of the driving wheels and the offside-front Wheel made the outfit pull to the right slightly, though not to a dangerous degree, on a dry road. The figures recorded from both the test speeds are quite good for an automatic-coupling artic, which cannot be expected to have particularly high braking efficiency because of the mechanical complication of the linkag% between the tractive-unit-mounted servo motor and the semi-trailer brakes.
As already noted, the average stopping distance from 30 m.p.h. was 10 ft. better than that obtained in 1960 with a four-cylinder model, whilst from 20 m.p.h. there was an improvement of 3.25 ft. Even so, stopping distances of more than 60 ft. from 30 m.p.h. are not particularly good for a vehicle of less than 20 tons totalweight. A fifthwheel-coupling model should be able to do much better.
Handbrake efficiency has been improved appreciably also when compared with the CH7TR, partly as a result of using larger brakes on the driving axle; an average Tapleymeter reading of 34.5 per cent was obtained from 20 m.p.h., accompanied on one occasion by 55-ft. skid marks from the offside driving wheels. This is a good handbrake figure, whilst the semi-trailer brakes also showed quite good efficiency when applied from 20 m.p.h. by use of the hand valve in the cab, a meter reading of 27 per cent being produced on average.
Fade resistance has been improved also, as a neutral descent of the Gleniffer Braes test hill was to prove, this descent lasting 3 min. 52-5 sec. and resulting in an efficiency reduction of 0.39g from 20 m.p.h. Fortunately, the air pressure in the reservoir stayed up during the descent, for it was obvious from the profuse smoking of all the brake drums that the linings had taken a beating, whilst the driving-axle brakes were so hot that even when the handbrake was pulled to the last notch it still would not hold the outfit. However, this is a very severe test and this being 920 so the Albion-Seammell showed up well so far as faderesistance is concerned.
A non-stop ascent of this hill was made before the fadt test, the length being 1-3 miles and the average gradien 1 in 13, with sections of up to 1 in 8 severity. The ascen was made in an ambient temperature of 17°C. (62°F.), an( the climb took 9 min. 31 sec., which is only 17 sec. les! than the time recorded in 1960 with the four-cylindei model. The engine-coolant temperature rose from 71°C (160°F.) to 80-5°C. (177°F.), indicating that the coolim