OPINIONS and Q UERIES STEAM REVIVAL VERSUS THE GAS TURBINE WAVING
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read the article by Mr. W. H. Goddard, in " your issue dated May 17, and that by Mr. J. Pickles, in the issue of September 20, it seems to me that Mr. Goddard rings the bell, and takes the coconut almost every time. Not quite always, though, as his suggestion that the gas turbine will never come into the road-motor powcr category is far too sweeping.
Both writers, curiously enough, neglect the possibility of electric transmission for road vehicles. Incidentally, the Brown-Boveri locomotive, first of its kind, employs electric transmission. Existing turbo-jet aviation power units have, admittedly, an extraordinary power-to-weight ratio, but nearly all the power developed is exercised in static thrust, a form of propulsion obviously unsuited to commercial vehicles.
Power, hitherto wasted in the rapidly turning turbine shaft, is now being utilized on aircraft by mounting an airscrew on the nose of the said shaft, but even for aircraft, the turbo-jet engine is still a shocking fuel consumer, except at really high altitudes. Static thrust is a very curious form of power employment. It needs nothing to push against, apart from the forward end of the vehicle (using " vehicle " in its widest sense). Hence the prospective space ship.
That small gas-turbine units for road transport purposes may be developed within the next 10 or 20 years, is, in my opinion, quite a possibility, always allowing for electric transmission to the road wheels, although this entails a loss in efficiency. Mechanical drive, as suggested by Mr Pickles, is an absurdity for the commercial chassis, e'en if it might possibly be used in racing cars.
If there were a road along the Andes chain, connected up from peak to peak by high-level bridges, jet-driven lorries might put up a show on it, but they would still be working at about 15,000 ft. below their proper eflicjency level.
No! The atomic pile, heating a boiler, will bring back steamers to our loads long before any turbo-jet unit becomes suited to the road haulier's purpose. With the rapidity of technical development possible in these days, such steam vehicles may be seen within less than 10
years ' L. GRAHAM-DAVIES. London.
[Our correspondent's reference to the views expressed by our contributor Mr. Pickles, is rather premature, as the article to which reference is made was the first of a series
• of five on the subject. We should appreciate the further comments of our correspondent when the series is completed as it is hoped to cover the whole aspect of the gas-turbine as a prime-mover for road vehicles.—ED.]
THE GAS TURBINE AND THE PSYCHOLOGICAL ASPECT I HAVE read with considerable interest the articles by I Mr. Pickles on the subject of gas turbines in your issue for September 20. Mr. Pickles refers to my effort of May 17, and has employed my five points as a partial basis on which to enlarge and explain his own views on the " pros and cons" of the gas turbine and its possible application for road-transport vehicles.
I agree with some of Mr. Pickles's observations, but would like to mention that, in a recent lecture to the 1.R.T.E., I said that the gas turbine is'ionly in its infancy and has a long way to go. I certainly am not bold enough or blind enough to assert that it will never be made suitable for road transport. With the tremendous rate of progress in all scientific and technical matters to-day, almost anything is possible, but I do say, again, that in the light of our present knowledge, the gas turbine, for many sound reasons, is quite unsuitable for road vehicles Mr. Pickles, l am sure, will be interested to know of something, quite apart from the design, manufacture, or performance of the gas turbine, which will make it still more difficult for it to be a success in this field. I refer to the psychological aspect—a subject on which, without boasting, Edo feel entitled to speak after some 16 years of pioneering the oil engine.
Most fortunately for all those of us concerned in that effort, the oil-engine happened to have many design features similar to those of the petrol engine, and all that one had to do was to learn about the injection pump, sprayers and the high-compression ratio. This
was quite easy and so it went well and was gradually accepted by every mechanic who had anything to do with it.
As compared with this, take the case of the gas producer (although I do not wish to be unkind to the gas turbine)—which caused more trouble, more profane lan guage and bad headaches, than anything else one can remember. This psychological aspect is one which we, in this country, are bound to take into consideration, and my long and hard experience tells me that if ever the gas turbine is put on the road there will be serious obstructionism from a great many in the industry.
Add to this the result of the 16 years of successful and highly satisfactory work by the oil engine and the very strong position it now holds in the industry, and we have the makings of a most formidable opposition to deal with before anything completely different, such as the gas turbine, can make headway or will be generally accepted.
The only thing that could alterthis state of affairs would be that the newcomer, whatever it be, could show some really great advantage in every direction, and this
surely is not the case with the gas turbine. One of England's foremost gas-turbine. experts, with an excep
tionally fine experience, recently outlined to me what he envisaged as being a possible gas turbine suitable for road vehicles. He claimed—probably rightly—a great reduction in weight (250 lb. for 200 h.p.), little or no vibration, smooth torque, ability to burn almost any type of fuel, no ignition system except for starting, and lubricating-oil consumption almost nil. All these points are agreed.
What I could not agree to were the following: The need for two exhaust pipes, each 4+ ins. diameter (to deal with the large volume of gases), the exhaust gases at
450 degrees C.; a top rotor speed of 40,000 r.p.m.idling at 10,000 r.p.m.; .the reduction gear necessary to
give 300 r.p.m. at the rear wheels; a thermal efficiency of only 22 per cent.; a speed ratio of 2+-1; two stages of compression, two stages of main turbine, a small twostage power turbine driving the road wheels, and a heat exchanger.
My expert friend also suggests that the size might be 1 ft. 2" ins, diameter by 3 ft. 4 ins. long. " The former dimension may be agreed, but to be able to fit all this machinery into a length Of 3 ft. 4 ins, appears to me to be somewhat difficult—if not impossible. Surely such a machine (or rather collection of machines), with all the attendant disadvantages as we know them to-day, could never hope to compete with the modern, compact, trouble-free oil engine, with almost double the thermal efficiency.
I am not pessimistic, but I have tried hard to be quite fair and straightforward in this controversy, and study the "pros and cons" as they are known to us now. My verdict—rightly or wrongly—can only be that the gas turbine is quite unsuitable for road transport, and would not be received well by the industry. With the greatest respect to Mr. Pickles and appreciation of his article, I cannot see that he has added anything to mine which could be constructed as putting the gas turbine in a more favourable light as regards its application for road-transport purposes. I adhere to my five points and now have to add one more—i.e., the matter of the large exhaust pipes required to deal with
the huge volume of gases. W. M. GODDARD. Leeds.
[In fairness to our contributor Mr. Pickles, the above critjcism is of the first article of a series of fivr on the same subject. Considerable research is being conducted in the gas-turbine field, and we believe that useful progress has been made towards overcoming some of the initial problems.—Eo.]
A BASIC SYSTEM OF FLEET MAINTENANCE
IVIAY I congratulate you and your contributor, Mr. 1T114. R. Morgan, on the subject chosen for the latter's article, "A Basic System of Fleet Maintenance," in your issue of September 20..
I, personally, would like to see much more discussion of this vast operation in your pages. In particular, l• would like to 'emphasize two points made by Mr. Morgan: (1) The anticipated activities, in the near future, of the Ministry of Transport Examiner or Certifying Officer.
(2) To say the least, the inadvisability of splitting up the three stages of maintenance.
While writing to you, may I correct two slight errors in the description of the equipment in my company's workshop?
(1) The Kitchen and Wade machines are, respectively, boring machine and honing machine, each being complementary to the other and used in the process of cylinder reconditioning.
(2) The portable drill is pneumatically operated, this type being chosen for safety and reliability under normal workshop conditions. The pits are illuminated by gas-filled lamps protected by unbreakable glass covers.
J. KEELING, M.I.E.C., M.I.R.T.E., Croydon. Workshop Manager, (For the Cement Marketing Co., Ltd.) EXCHANGE-UNIT SYSTEM SUITABLE FOR SMALL FLEETS
I WOULD like to comment on a paragraph in the
article "A Basic System of Fleet Maintenance" which you published on September 20. It reads in part: "To the engineers of these small fleets (100 vehicles and under) the 'unit exchange' system is practically out of the question. . . ."
As I have pointed out in these columns on previous occasions, the exchange-unit system is not "out of the question" to the engineer in charge of even one machine.
In support of this statement I give plain practical proof as follows:—
The owner of one or any number of the make of vehicle distributed by my company can, at any time, demand and receive from our stores any of the following exchange service units which are kept in sufficient duplicate to fulfil all dernands:—Engines (oil and pertol), front and rear axles, differential assemblies, gearboxes, clutches, radiators, water pumps, injector pumps, injectors, chassis frames, refaced brake shoes, springs. dynamos, starters, carburetters.
No surcharge is added for the capital cost of these units.
This service, I submit, places the owner of one machine in a superior position to the owner who keeps his own service units for 501) machines. He is entirely relieved of the problems of stocking, obsolescence, the engineering difficulties involved and the capital expendi ture. T. G. StarEa, Director, Leicester. (For Ford and Slater, Ltd.).
HE CONCURS WITH MUCH SAID BY MR. LISSE NDE N
I WOULD like to accept your offer of receiving' opinions on matters raised by Mr. Lissenden in your issue' dated September 13. You ask 'that criticism should be constructive, and I will try to make it that within the limits of a letter. You urge also that criticism should be designed to rebut any charges wade by _him against road transport—this is difficult because what he says is, in the main, only too true.
The point on which I join issue with him is in his support of the Government Road Haulage Organization. because, in my view, it was unsatisfactory, thoroughly uneconomic, and operated under what were virtually owners' risk conditions That is a broad statement and 1 realize that your space would not allow of one putting forward facts and figures in support of it.
However, what of the future? That is the important thing, and on this Mr. Lissenden is perfectly right' and tere is a great deal of confusion of thought on this subject. , If the railways are to re-organize—as they will do—and road transport contractors are to become. within limits to be ,discussed and agreed, common carriers, then it is, to my mind, as certain as night following day, that the C-licence holder will have to face some restrictions.
If road and rail are to work together (let us leave out canal, sea and air transport for the moment), then it is inconceivable that the ancillary user can be given complete freedom to undermine the foundations. That he should have a certain amount of freedom, I fully agree. but I feel with Mr. Lissenden that it should be confined, in the main, to local delivery, and "local" can still be a freely interpreted expression.
In the main I oppose nationalization, but, frankly, I have never been able to see in the suggested nationalization of inland transport, which, as I understand it, has not been cancelled but only postponed, all the horrors which are imputed to it, although I would still rather be without it. But whatever the future holds, ,Mi Lissenden is very right in saying that what traders want, under any system, is freedom to use that form of transport which best suits their businesses, and there are people who argue that only under nationalization will that be possible. Traders also want to be free to use their own vehicles, but I believe that most of them would be prepared to accept some limitation.
I think M. Lissenden has said what has wanted to be said for a long time. Now that he has retired, I believe. from full-time employment, and will therefore have, possibly, a little more freedom of expression, I hope he will give us a good deal more from his store of knowledge of the industry.
H. R. CAuLFIELD-GniEs, Transport and Traffic Manager (For Newton Chambers and Co., Ltd.). Thorncliffe Works, Near Sheffield.