• Home
• Used vehicles
• Product news
• Dealer news
• Compliance
• Buying advice
• Archive

FUTURE DESIGN REQUIREMENTS IN PASSENGER

VEHICLESearly in 1963 completing 25 years' service

with the British Electric Traction Group.

This was the second paper presented to .The Commercial Motor" Fleet Management Conference

WHEN, :.. HEN,.a few months ago, I was requested by The . Commereial 'Motor to present a paper upon the above subject it flattered my vanity enormously and I readily complied; but when I came to look into the matter more closely .1 tended to reverse my feelings and now I

am convinced that it is by no means the sinecure that I first thought it to be. In fact, it is a subject that has been written and talked about so often in recent years (it is surprising what a lot of prophets we have in our midst) that now it becomes a matter of paying your money and taking your choice, and you can have any kind of future you wish. I have derived a considerable amount of interest (not to say 'amusement) from reading what some earlier writers have tO say, some of whose predictions have come to pass; but, mainly., we are still awaiting results.

At the outset, before considering the trends for the future, I feel it might not be a bad idea to reflect upon what has happened in our industry during the past decade. The more one thinks about it, the more one is convinced that we have not made so very much progress. Admittedly we have been able to increase the overall dimensions of certain of our vehicles`, but this has not been possible on all types because until now weight limitations have prevented us from obtaining the maximum dimensional advantages.

Have we, during this period, made any substantial advance in engine design? Well, apart from the Perkins differentially supercharged engine, the answer is that there has been no major step forward. Of course, if this point were put to the various manufacturers they would undoubtedly say that there have been improvements and, whilst' I agree with them, up to a point, I think that these are only marginal. I must say, however, that we are getting much improved life from these units. The old troubles of excessive carbon deposits around the valves, heavy bore wear, ring sticking or, alternatively, rapid peripheral wear of the top ring, have been largely overcome. Credit for this lies in the adoption of chromium rings, possibly the reduced sulphur content of the fuel and, what is even more important, the introduction of better quality oils. These points, coupled with the tendency to leave engines alone if they appear to be running well, have resulted in substantial improvement in fife.

I do not think that we will go back to the old habit of stripping units for the express purpose of seeing if they are still working, and this does not apply only to engines but to all other units as well. Our records, in conjunction with a brief test by a competent person, will tell us all we need to know. This so-called preventive maintenance has cost us vast sums of money in the past.

(?50 It is stressed that better oils have helped us consicie ably. It is hoped that the oil suppliers will continue t produce oils of even better performance—at a cost we Ca afford, let me add—and so keep pace with the constant] increasing stresses that our engines will have to meet.

There is, of course, an increasing amount of interest i gas turbines and rotary combustion engines; but I fe that both alternative power units will continue to suffi from the troubles we now experience with our presei engines (i.e., noise and smell) and a considerable amoui of development is necessary before they can compete c level terms with the latest types of diesel engine.

Can we say that our suspension systems have improve( Well, yes, at least we can say that improved systems a available; but most of us still cling to the old laminatt springs, not because we like them or they are cheaper i operate—they aren't—but because we do, in fact, tight st of the initial cost of some £200 to 000 extra per vehicl In terms of, say, a fifteen-year life, this represents an ou lay of only £13 or so per annum. In view of the improv( ride and the lower suspension maintenance expenses, pi the long-term advantage of reduced stresses on the bad it is a small amount to pay. We really ought to jump the opportunity that now presents itself.

So far as other components are concerned—such transmissions, axles, frames, wheels, electrical equipmei clutches and brakes—the position is that there have be' no substantial improvements with any of these. In certa instances such items as clutches, brakes, and electric equipment are giving far more trouble now than they di say, 10 years ago.

Tyres have improved (e.g. radial plies and metallics) ai the adoption of such tyres has been of considerable bend Operators are delighted with the progress that the ty manufacturers have made here, and no-one can deny th improved fuel consumption figures have resulted. It is lc however, that the reluctance to produce tubeless tyres f p.s.v. work needs to be broken down, and that the rnc general adoption of such tyres would give us still great benefit.

Midland Red has shown us what can be done in respc of independent suspension, they having used this syst( for many years on probably more than a thousand vehicl They are convinced that this method is well worth wh and results in improved riding with reduced roll eharacti istics; but the large chassis manufacturers still have to persuaded that this is what we all want.

Referring now to bodywork, two years ago I would ha lid that one of our oldest problems has now been overome completely—and I refer to corrosion of the body Tuctures—but it has come back with a rush, and we now ave this problem to deal with on a scale which is far tore severe than before. I think that the increased amount f salt used on roads during recent winters is probably le main cause; but the position is such that our bodyuilders have nothing upon which to congratulate them:Ives.

It is possible that light alloy structures may be the answer r this problem or, alternatively, the adoption of the proess of galvanizing body understructures; the latter will aturally increase the weight but it should be most effective gainst corrosion—and either step will increase costs. It can be said that we have improved the general lines I our vehicles and, of course, the increased length of the ngle-decker has helped. Attention to the shape of front ad rear domes, curved windscreens and rear windows has 11 helped in this direction. So far as appearance is con:rned, any further substantial steps can only be taken y reducing the numbers of passengers carried—and this Des not seem to be very practical.

The use of improved internal finishes and the large scale loption of plastics is I feel, a considerable advance, so ierefore the position is not entirely negative.

THE FUTURE—PASSENGERS' REQUIREMENTS ZO much for looking into the crystal ball in reverse; now what of the future? My terms of reference are Future Trends in P.S.V. Design ": in my way of thinking, as subject has been dealt with by those who are far more )1e than). However, we are tending to use larger vehicles f greater passenger-carrying capacity, and this trend will adoubtedly continue. We are endeavouring to improve le standard of comfort for the benefit of passengers and to encourage them to ride more and more on our !hides. We still persevere with vehicle weight reduction; it we are probably fighting a losing battle in this direction !cause of the use of larger overall dimensions, increased issenger loads, larger engines, bigger tyres and numerous .her things which we are now convinced we cannot do ithout.

We are also tending to use large single-deckers in place double-deckers and, although many of our municipal anagers may not agree with me, I am sure that the very rge-capacity articulated single-decker of the type used on e Continent is ideal for town services. These vehicles are ,ed in many cities abroad and can carry standee loads of r to 180. They handle exceedingly well and can negotiate ,rners and turns equally as well as our rigid types, and ey have the additional advantage of all passengers being icier the observation of the driver, or conductor when the tter is employed.

It may be thought that it is risky to introduce articulated hides which, in the past, have been so prone to "jackLife" at the slightest provocation; but considerable strides ive been made recently in establishing just why artics ack-knife ", and this is largely on'account of unbalanced liking. Now it is becoming possible to use the antiaeel-locking device and, additionally, there have been teresting developments in damping the artic turntables. feel that everything points to the fact that this old prohn is on its way out.

I am also most impressed with the more orthodox singleckers used abroad, with low floors and rear engines, for

-ge-capacity standee one-man operation. I trust that my

teners will not feel that I have adopted the attitude that cause a thing is foreign that it must automatically be tter than our own; this is not so, but at the same time should remember that other countries have very similar traffic problems to ours and they cope with the carrying of passengers exceedingly well by means of these very largecapacity vehicles. When one studies the manner in which these large one-man operated buses work, particularly at peak hours, one is immediately impressed by the simplicity of the method whereby one man can cope with 80 to 90 passengers in a busy city. The secret, of course, is that practically all travellers are pre-booked and carry weekly or monthly tickets; there is very little in the way of cash transactions and thus the driver-cum-conductor has a relatively easy task.

The introduction of the rear-engined chassis by more than one of our manufacturers is a step towards the large capacity version of the Continental type of bus, which I am certain we will see in service here before vet)" long. There is no difficulty in producing such vehicles, and I have a feeling that the Ministry of Transport will be co-operative.

At the beginning I concentrated upon the vehicle as a whole, because that is what we offer our passengers and because we endeavour to attract them from other forms bf transport. Taking for granted that a safe ride is the outstanding requirement, then comfort is a good second; therefore, the best possible suspension is vital, and here I feel that air or full rubber suspension will become the standard.

SEATING AND TRIM

MANY operators ruin an otherwise excellent vehicle by LYL crowding in far too many seats. The design of seat, its workmanship and choice of materials can be of.the best; but if it does not provide sufficient leg-room then the whole effort is wasted. I strongly maintain that one row of seats less than the legal maximum will provide very reasonable comfort.

The aesthetic features of a vehicle interior are also vitally important, and in many cases old styles of trimming and finishing materials and colours are retained in vehicles which cry out for a more modern style. It is recommended that more use is made of the material suppliers' design and styling teams. This has already been done with great advantage to certain users and I think that this is a process which could well grow. •

Still on the theme of passenger comfort, I think that the elimination of wheel boxes is very desirable, and a good attempt in this direction is shown on the Bedford VAL chassis with its smaller than normal diameter wheels. In a vehicle where we need a single-step entrance and a very low floor height, wheel boxes tend to become even more prominent and objectionable. The best solution to this problem is the use of back-to-back seats which, however, results in some passengers facing each other. I cannot understand the apparent objection to this, for it is standard practice on main line trains and tubes, and nobody regards it as an obstacle. There is the advantage that each passenger has a perfectly level floor upon which to place his feet.

HEATING AND VENTILATION

A FURTHER physical condition that can have far" reaching effects is the provision of adequate heating and ventilation. This is a subject which has received very half-hearted attention for many years with the result that heating and ventilating systems, until recently, have been most inefficient. Passengers have been very long-suffering and that pre-War horror, the re-circulating system which does nothing but create a fug, has been foisted upon out passengers for far too long: likewise the ventilator which consists of merely opening a series of large holes in the sides of the body, so causing an appalling draught. I refer to the sliding lights.

At long last we have a system which really does heat and ventilate, and to get the best ,results we have to discard certain items hitherto regarded as essential; for instance opening windows which, in order to have an efficient system correctly controlled, must be eliminated. The system must work fully automatically and interference by driver, conductor or passenger must be completely ruled out. Heating and ventilating systems now exist which take into account both of these points, and they are being installed in increasing numbers. 1 think that in a few years time, without doubt, the automatic system will be in general use.

Associated with heating and ventilation is the question of adequately demisting the driver's screen. Whilst an efficient ventilating system will help matters, something far in advance of present methods is essential to ensure perfect demisting and defrosting.

Aircraft and main line trains have the answer and it is obvious that we must eventually follow suit. I refer to the electrical element method that either coats the inner surface of the screen glass or is embedded in the laminations. In the first instance a coating of gold is provided, but so thin that it does not restrict the vision in the slightest degree. Alernatively, the embedding of a very fine wire— again practically invisible—between the two sheets of glass forming the laminate is another method. A small electrical current passes through both of these systems and raises the temperature of the glass sufficiently to ensure clear vision under all circumstances.

We have, however, rather complicated matters for ourselves in this direction by introducing curved screen glasses, which will increase the cost of these demisting systems to such an extent that we might have to revert to the flat glass screen.

Of course, we might give some further thought to double glazing of screens, providing the air space could be permanently and hermetically sealed; but, judging by the standard of double glazing seen recently on railway rolling stock, I feel that a really efficient system of this type is a long way off.

In considering the standee type of vehicle. I think that a fresh layout of side windows is desirable in order to enable the standing passenger to see where he is and just what is happening en route. The U.S. vehicles provide a row of shallow windows immediately above the normal side windows, so as to provide this extra vision. Such a step in this country would, however, call for some re-thinking upon the subject of luggage racks, but there is no doubt that such windows would make a standee ride much more attractive.

PASSENGER FLOW IN HIS paper read before the Scottish Road Passenger Transport Association earlier this year, Mr. Perring, Chief Mechanical Engineer, Ministry of Transport, stressed the need for a one-way flow for passengers within the vehicle by means of an entrance door and an exit door. This, again, is extremely important and desirable from the point of view of the passenger and the conductor.

NOISE

A FURTHER aspect of p.s.v. travel of which we are all

becoming increasingly conscious, is noise. Quite apart from the general level of noise within our cities there is, again, the comfort of our passengers to consider. In the old days—I mean a mere 10 or 15 years ago—the internal trim of vehicles largely consisted of soft soundabsorbing materials, even on ceilings, side panels, etc. But now we have gone over to hard-faced plastics that are so easy to clean, yet which have the effect of intensifying noise from the many sources. There is no going back G54 in-this respect, and we must find a means of reducing nois( at its source . . . but more of this later.

DRIVER AND CONDUCTOR

NAOST of the points referred to so far have cOncernec

the passengers. A few have some bearing upon du crew (e.g. noise, one-way flow in saloons, heating an ventilation, demisting of drivers' screens, etc.); but there are many other features that undoubtedly will be adoptec in the foreseeable future.

Firstly, there is the question of power-assisted steering so many vehicles built nowadays are very close to tit( limit in this direction, and only by the adoption o. palliatives do they become serviceable. With the increasini all-up weights, some form of power assistance or a corn pletely new design of steering gear will be needed foi many vehicles.

Likewise automatic, or at least semi-automatic, trans mission is desirable; not just in the big cities but generally At any rate, I think we will be forced to adopt the fluic flywheel, as the plate clutch is becoming a major problen again brought about by the increase of vehicle weights greater power being transmitted, and more and mon congestion on the road.

I think that the operator will gain substantial advan tages from the adoption of automatic transmission, foi a great deal of our maintenance costs arise from the mis use of the vehicle by the driver, the most serious aspec of which is the practice of getting away from a standstil in the higher gears, thus placing severe strain on the trans mission in general and the clutch in particular.

A most important improvement which is needed in thi driver's cab layout is the positioning of the electrical con trols and switches. At present every operator has z different layout All insist that some standard is necessary but all equally insist that the standard must be their own so we just get nowhere. Eventually, it must be possibli for every driver—no matter what concern he represent: or what make of vehicle he is driving—to be able to locate exactly, day or night, the starter switch, dip switch, doo: controls, interior lights, etc. All vehicles should, in fac MUST, be identical in this respect.

CHASS/SLESS VEHICLES

WHY do we still buy a separate body and chassis? On1!

because they are available and thus give the custome the widest choice of alternatives; but we, the customer, pa] heavily for this privilege and if, instead of being offeree literally hundreds of alternative combinations, we were ti boil them down to a dozen or less who would be the loser' Roth we and the manufacturer would benefit. The adop tion of chassisless structures would result in improyemen all round, particularly in weight and cost.

A review of chassisless vehicles built and used in othe countries reveals that they are excellent vehicles in al respects and passenger appeal is by no means restricted It is not suggested that we are doing nothing about thi matter. Some progress is being made; hut so very slowly particularly when one thinks of the small percentage of thi total p.s.v. in this country that are built in this manner There are some excellent examples of this method o construction (e.g. London Transport Routernasten Midland Red double-deckers and Single-deckers am M.C.W. Olympics); the latter, incidentally, is an excel lent vehicle for overseas service but too heavy for thi country. In other words, we are handicapped and dis cOuraged from using an otherwise very desirable vehicli because its fuel consumption is greater than that of ou normal vehicles, and thus Fuel Tax would hit us hardet THE ALL-WELDED STRUCTURES I HAVE been most impressed by the continental methods of construction vehicles: I refer to the all-welded struc :ure employed almost without exception. Over there, gone ire the days when frame and body sections were drilled ind bolted or riveted with a multiplicity of strengthening ,rackets. The continental designers and engineers weld all )f their joints and they are not necessarily overlapped, but n many cases are straightforward butt joints. What is nore remarkable, their vehicles do not fall apart as one night expect—in spite of roads which, in many cases, are lot as good as our own.

To my mind, this is a valuable lesson to us, and I am ;lad to see that certain of our bodybuilders are, rather :autiously, adopting this procedure. I hope that they will x encouraged to better efforts in this direction and that mr operators will not discourage them, for I am convinced hat this is the method of construction of the near future.

A final point in this connection—the welding process nust be handled by a thoroughly qualified welder, such as me would expect to find in the aircraft or shipbuilding ndustries, with either B.O.T. or A.I.D. certificates.

BRAKES

IPON the subject of brakes: I do not want to dwell too long here, because we are to hear another paper this ifternoon which deals specifically with this subject. However, let me say that brake efficiency has been standrig still for far too long. in referring to efficiency I do tot mean "stopping distances" or percentages of "g" but nechanical efficiency; where short life and definite failures if materials such as the cracking of brake drums, heat :razing of drum surfaces, rapid wear of linings, air diaihragm failures, etc. are experienced—all too frequently. Jnfortunately, the manufacturer seems wedded completely o the design of brake now used for many years, and nothng that we—the operators—say makes any difference. 7ai1ures occur because the design is inadequate, or the naterials used are just not man enough for the job. A naterial change is made (e.g. to a slightly more exotic iron or drums) and this just manages to do the work; but a light intensification of operating conditions and we are in he same trouble again, and so it goes on.

We must have better and more reliable brakes. Having ad considerable experience of the Midland Red disc wakes I am convinced that, within certain weight limitaions, the disc brake is ideal for our work. Chassis manuacturers will insist that this weight limitation is an asuperable problem; but let us go back to Midland Red there they have probably over a thousand vehicles on disc wakes, all performing most satisfactorily.

Again the chassis manufacturers put forward the argu:lent that the high temperatures at the disc result in the oiling of the brake fluid; but ,this, again, is not a valid eason for not using them because Midland Red does not offer from this trouble. Admittedly they did originally, but ie adoption of mineral oil as a hydraulic fluid has overome this difficulty.

One can go further: one of our largest manufacturers f braking equipment has a well-advanced disc braking theme wherein the brake pad operation is entirely iechanical and is unaffected by temperature. In fact, this esign of disc brake is capable of being operated (i.e. the ressure exerted on the mechanical connection to the pad y either vacuum, air or hydraulic power) in the same way s the drum brake.

A further point regarding the braking of our vehicles is le need for an efficient retarder; most of those in use are xcessiveiy heavy, bulky and expensive. But I have seen esigns recently from one manufacturer, of braking equip ment which seems to have none of these faults. it is hydraulic in principle, it is operated in conjunction with the normal brakes on the vehicle, and it is capable of giving a constant retardation of approximately 01 to 012g. This, I feel, would make a valuable contribution to braking and a reduction in brake maintenance costs.

AERODYNAMICS OF COOLING SYSTEMS L' OR many years we have suffered poor engine tempera' ture control due to inadequate engine cooling systems. By and large, our diesel engines are over-cooled, mainly because we have to accept from the manufacturers a cooling unit in common with that supplied to overseas markets. We lose a great deal of engine efficiency on this account, and it is felt that it is about time our own specific requirements were considered.

Maintenance of the cooling water at the optimum temperature would bring about more efficient operation of the engine. Additionally, a much quicker warm-up would result in improved heating systems.

A new set of conditions are now presenting themselves in this country—high speed running on motorways—and here a much improved temperature control is called for, as not only do these vehicles have to run for hours at constant high speed with the resultant high heat losses; but also they must run in the cities at each end of their service, and here the engine conditions are substantially different.

The present use of thermal control of fan drives is a useful step towards such control but it is not the last word. Further development is required and much greater use should be made of the wind tunnels, such as that in use at M.1.R.A., where it is possible to use a full-size singledecker for air .flow purposes.

I feel sure that we no longer need the orthodox type of radiatot with its large exposed frontal area, and that it could be cowled down on its forward face with great advantage, the cowled surface being adjusted automatically by thermostatic control. This would restrict heat losses when necessary and also reduce the losses incurred in pushing these power-consuming surfaces through the air at high speeds. Many of our coaches and buses are even now running at speeds of 80 m.p.h. and it could well be, in the not too distant future, that speeds will be in excess of this.

It is thought that wind tunnel investigations into the aerodynamics of other power-absorbing surfaces and orifices could result in fuel economy. Furthermore, another desirable feature could be the adequate cooling of brakes by a controlled air flow.

In view of the limited size of the 'existing wind tunnels, it may be necessary to deal with this work on, say, half size models; such investigations, of course, would be expensive, but if some degree of co-operation existed between the chassis manufacturers and the major bodybuilders, then the results would be well worth while.

. PROPANE AS A FUEL THERE appears to be an 'increasing interest in the use of

I liquefied propane as a fuel in diesel engines; this is particularly noticeable on the Continent where a fairly large number of buses use this fuel exclusively. It is an interesting point that, in certain European cities, bus operators are prohibited the use of diesel engines because of their smoke, smell and noise: propane has the effect of practically eliminating the risk of smoke, substantially reducing noise and, if one can believe these operators, it reduces wear and tear on engines.

From the above, this is obviously an attractive fuel in many ways, but its calorific value is low when compared with derv, it having only approximately five eighths of the heat value per gallon. Thus, in terms of work done, a greater quantity of propane is needed and, furthermore,

if this fuel were to attract the same amount of tax per gallon as dery then the advantages would be lost. In fact, operators could not afford to use it. With some encouragement, however, from the Chancellor of the Exchequer it would be an excellent substitute for derv, not only for the operator but also for the public as a whole; our vehicles then would be less likely to smoke, they would be quieter and smoother. For the near future it is a fuel that must not be ignored in this country, and the authorities should give us every encouragement to use it.

ELECTRICALLY-DRIVEN VEHICLES IN previous sections of my paper I have referred to 1 the existing objections to the diesel engine and, quite frankly, I cannot see any appreciable step .being taken to reduce these objections. Even if the manufacturers were to produce a unit with a much greater safety margin so far as retention of tune is concerned-human nature being what it is—adequate maintenance of such a power unit would be neglected and thus could not fail to produce inefficient running, and so the old troubles are inevitable.

1 think that the only answer to the problem is to find some alternative source of power, and, what could be cleaner and quieter than electrical power? The most promising system appears to be the fuel cell and, although little is heard of the system in this country, in other countries a considerable amount of research is going on and showing most promising results: in fact, reports from Sweden are most encouraging. Mr. 01le Lindstrom, in his paper entitled "Swedish Fuel Cell Development ", sets out clearly the work that they are doing in this field.

Mr. Lindstrom points out that, whereas, the present price of fuel cells corresponds with that of thermo-electric generators now on the market--and remember that such fuel cells that are :being built are prototype sets and are therefore very costly—yet he foresees that a capital cost of £7 per k.w. should lie within the realms of 6ossibility when fuel cells have been fully established.

Thus a fuel cell unit of 100 k.w. output should cost £700 which, at present-day prices of more orthodox power units, seems to be most competitive.

Furthermore, Mr. Lindstrom says: "Trucks with fuel cells combine the good economy of the battery truck with the higher running and working speeds of the combustion motor driven truck (therefore, why not buses?). He also says that he can foresee the fuel cell power unit being eventually so "light and compact that it can be incorporated in private cars.

So much for the comments of an expert. It must be agreed that the prospects are bright; but in the meanwhile, how can we achieve something approaching this ideal? 1 suggest that the battery-driven vehicle is well worth investigation.

In its simplest form, there is the house delivery van— there are some forty to fifty thousand of them in this country—and a very good job of work they do, too. They are cheap in first cost; their running costs are low and, when they stand outside a house or in traffic—as our vehicles do—then apart from the labour charges, their running costs are nil.

Mr. H. W. Heyman, B.Sc., M.I.E.E., managing director of Smiths Delivery Vehicles Ltd., and probably one of the greatest authorities upon such vehicles in this country, can foresee a most attractive future for the battery electric vehicle, even for p.s.v. work. hi his paper entitled, "Electric Road Transport: The Promising Present and the Challenge of the Future ", he describes with great clarity the advantages of such vehicles, when used for frequent stop and start work, as compared with the internal combustion engined vehicle.

Operators who have dispensed with the services of tram and trolleybuses will. I feel sure, hold up their hands horror at the thought of resurrecting electric vehicles; bu conditions have changed, even in recent years, and th, amount of time spent idling in traffic is increasing annually So why use an engine that constantly consumes expensivi fuel, that smokes and fumes, and is noisy as well? believe that the authorities will ultimately wean us Iron internal combustion engines.

One of the criticisms of the earlier electric vehicles wa the failure of insulation due to the effect of moisture am corrosive salts; but I maintain that since those days thi introduction of new plastic insulating materials ha reduced—if not entirely eliminated—such troubles.

The modern battery vehicle is a much more exotic pieci of equipment than the earlier models. In the first place the use of transistors has revolutionized battery chargim procedure, and nowadays a mains voltage lead can La plugged straight into the vehicle, without converters.

From the point of view of vehicle performance, it obvious that the modern battery is vastly different Iron the battery of even ten years ago, and it is capable of mph charge and discharge without detriment. It is thus possible to charge such a vehicle at a much greater speed thar hitherto and, what is more important, it can withstanc higher rates of discharge equally well and therefore it i: capable of giving a much better vehicle acceleration figure 1 think that such a vehicle, although not having a hie maximum speed (it is not necessary in city traffic), woulc have excellent acceleration..

In designing a vehicle specifically for p.s.v. work, bat. teries could be palletized for quick removal by fork-lif truck, with rapid plug-in connections and toggle clam' fasteners. The batteries, as is common in the U.S.A., coulc be hired from the manufacturers at so much per mile.

Investigations into the pros and cons of regenerative braking would be desirable: a most interesting develop. rnent noted recently on battery-driven mine locomotives the differential generation of power from separate motorized wheels: (see paper by H. E. .I. Symes, M.Sc (Eng) read before the South African Institution 01 Mechanical Engineers) the wheel on the outside of a benc or curve acts as the motor whilst the inner one becomes generator. Thus we have an additional source of extra power or the equivalent of greater battery capacity.

With increasing electrical generation facilities in thi country and, in particular, the vast possibilities of atomic power stations, it is conceivable that the costs of current in the future will be much lower than now; therefore the cost of battery charging should be less. But even now taking into account the capital cost of such a vehicle together with the charge for current at, say, Id. per unit the cost of running compares very favourably with more orthodox vehicles. Some time and money is necessary tc prove the advantages to be. derived from the most modern thought on battery driven vehicles. I am sure that the battery manufacturers will co-operate, as will the battery vehicle specialists, we only need an operator to be bold enough to take part in such an experiment.

In conclusion, I feel that there is unlimited scope for development of road passenger vehicles and that there is little fear of stagnation in design. I am convinced that as operators of such vehicles, we can, if we speak reasonably of one mind, have just any type of vehicle we require. The manufacturers will produce anything; but he must be pushed very hard and, as now, the urge to do this must come from us.