FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1920
1920 - 1079.PDF
t" OCTOBER 14, 1920 to do it, and some of the machines may, therefore, suffer unfairly, in the comparison, as these good qualities of relia- bility and safety, which go to make the first high capital cost, are not reflected by lower operating charges, as no doubt they would be in actual service, and so justify the first heavier capital cost. Then again there is nothing to indicate the comparative values of the comfort and convenience of the different machines. It has been said that " Comparisons are odious," and one feels under some difficulty in making comparisons of the types of machines produced by various makers. I have, however, endeavoured to deal impartially with the figures, and if some of the machines or engines come out apparently unfavourably from the constructor's point of view, I hope the effect of the comparison will be to assist those con- structors to develop their new types more efficiently. In anjr case, it is open to any prospective transport company to make out a similar statement should they so desire, and ^there is therefore nothing to be gained by anyone objecting to the comparisons. One fact that emerges from this statement is the com- paratively higher cost of operating machines which were originally designed ^for war purposes, and which have more or less been completely re-modelled for civil transit. I have marked these machines in the statement. This is more especially the case with the single-engined machines as the twin-engined and multiple-engine machines have the advantage of spreading the charges over a greater number of passengers or a greater amount of cargo. The statement, however, shows that progress has already been made since the end of the War. Moreover, we are only dealing with machines which are at present available, but I am glad to say there are other machines in course of construction which will show results of a still greater efficiency. The costs, then, under examination should be still further reduced, and the possibility of a service such as we have considered being placed on a paying basis will be brought appreciably nearer. Examining the statement more closely, we see" that the cost per flying hour and per aircraft mile lead us on to the true test of efficiency in our comparison, i.e., the cost per passenger/mile or cost per ton/mile. Taking the cost per passenger/mile first, it is perhaps better visualised by a comparison in which the definite dista^e, viz., 240 miles, is considered, and, in order that we may talk about proba- bilities, we will take the load factor of 75 per cent., and the figures under Item 30. On reference to the comparisons under this heading, you will see for example an interesting state of progress in the case of the Airco machines. Whereas the Airco 9's cost ior the journey is £17 10s., the Airco 16 is £13 4s. The latest type, Airco 18, comes out at £7 45. Another point that will be noticed is that, whereas in some cases the passenger cost is comparatively high, the cost per ton/mile does not bear the same ratio. For example, it will be seen under Item 30 that whereas the cost per passenger journey on the 0,400 Handley Page is £11 85., •which is but little higher than the " Bristol " triplane, the cost per ton for the journey is ^95 16s. for the former machine, while it is only £50 55. for the latter machine. This result is brought about by the fact that the carrying power of the •" Bristol " triplane is not being fully utilised in carrying only fourteen passengers, and that the allowance of a considerable amount of room for the comfort of the passengers in this machine is being paid for by a higher running cost. If, however, we were utilising its full weight-carrying capacity, •we should get a more efficient cost figure. In this connection too it will be seen that the W.8 Handley Page shows a substantial improvement on the o 400, the passen- ger figure being £y 145, Od., and the cargo figure being /44 19s. Another interesting fact is apparent, and that is that the cost per cubic foot of cargo may also vary in different ratios to the cost per ton/mile, i.e., we may be able to carry a certain weight, but if the cargo is of a bulky character there may not be sufficient cubic capacity to hold it. We find, therefore, that ample cargo space fully utilised may reduce our figure. A further most important fact jumps to our notice, that is, the high proportion which the cost of petrol '""bears to our total costs. I have purposely not gone into the question of the fares and rates charged. It is the other side of this subject, and the corollary to the side we have been considering. The two sides of the business are interwoven. The fares and rates you charge are governed by what can be properly charged, and what the travelling public will pay for the particular services rendered. The charges must be so based as to attract a sufficiency of public support to economically spread the Standing charges of the undertakings. On the other hand the fares and rates charged must, to make the business successful, provide a margin of profit over and above all the operating costs and other charges. It follows, therefore, that the lower we can bring our working costs the lower are the fares that can be charged, the more attractive to the public will the services be, and more generally used, with a consequent greater success in every direction. To sum up this chapter, the figures I have shown clearly demonstrate that even with high load factors existing types of machines can show little, if any, profit. The demands, therefore, come to the aircraft and engine constructors for continued progress. CHAPTER V. Future Demands of the Transport Operators on the Aircraft Constructor. 1. Passenger Aeroplanes.—Taking as our first type the passenger machine :— This machine may be of varying size, but there are certain qualities called for in all. The essential qualities are Safety First and then Reliability. I do not propose to go into details of how those qualities shall be attained. The constructors and their designers know perfectly well what is called for under these headings. All I would urge is that they are essentials. Turning to the other qualities, on which there is considerable scope for variation, there is the question of comfort. Already in the modern aeroplane this has been catered for to a very fair extent, and it must be still further developed. It not only makes air journeys more agreeable, but it has the effect even of inspiring confidence. In connection with this same question of comfort there is a desirable feature called for, viz. : The suppression of the present deafening noises of the engine, propeller, etc. Air travelling will be greatly popu- larised if these noises could be eliminated. The question of speed, and by this I mean crusing speed, is of great importance. Speed is the asset of the aeroplane, and, while the present cruising speeds of about 100 m.p.h. are satisfactory, it would appear that every endeavour should be made to increase this quality in aircraft provided always that it is not brought about at the expense of economy. With regard to the range of flight, it will probably be found that 350-400 miles is ample for ordinary passenger services, as undoubtedly these services will be worked on the relay system, and the stages are unlikely to be greater than about 300 miles. Moreover, until the aeroplane has reached a much greater perfection of comfort passengers are hardly likely to be willing to stay on board for extended periods. Another quality, viz., economy of running, as we have already seen, is forced on us by the consideration of cost. Obviously the most effective way of reducing our costs will be to increase the useful load carried while still using no greater horse power. In other words if we can lift double the weight for the same horse power without detracting from our speed we should be in a position to run our services on profit-earning lines. With regard to the size and carrying capacity of the machine, this must be governed from time to time by the demands which are made on the transport companies for passenger accommodation. It is obvious from our figures that it is economical to use the machine which, in service, most closely approximates to the amount of traffic to be carried so as to produce a 100 per cent, load factor. The constructor must necessarily be guided on this point by the requirements of the transport companies, who will no doubt call for larger and larger machines as the passenger traffic develops. Wire- less equipment we have already said is essential for all future types of aircraft. 2. Mail and Light Goods Aeroplanes In common with the passenger machine safety and relia- bility come first, but the special feature of this machine will, no doubt, be its speed. The probable cruising speed of this machine would be not less than 120 m.p.h. Using these machines in relays, Continental capitals such as Rome, Madrid, Vienna, Berlin, Constantinople and Warsaw would be reached during the night. To work on the relay system, it is essential that a system of standardised mail or goods containers should be adopted. The fuselage should be so constructed that containers or boxes could be filled with the mails or parcels at the G.P.O. and sent straight down to the aerodrome and placed in the aeroplane without delay of further handling. At the end of the first stage these containers would be transferred to the waiting machine and, being standard, should fit exactly into place, the transfer being thus only a matter of minutes, and that machine would pass on to the next machine, and so from stage to stage. I think it is quite obvious that, when long aeroplane services are operating, involving either changing mails or goods from one machine to another several times, such a syst ?m will be essential, and it is most desirable that the Air Ministry, I08l ••/
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
