FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1935
1935 - 0203.PDF
JANUARY 24, 1935- FLIGHT. 107 CIVIL AERODROME DEVELOPMENT Need for a Central Control Board Again Stressed : Points from a Paper Read before the Institute of Transport by Sir Leopold Savile NOT only at the S.B.A.C. Conference has emphasis been put upon the need for a civil aviation Central Control Board. The point was also made in a paper on civil aerodrome development read before the Institute of Transport in London last week by Sir Leopold H. Savile, K.C.B., M.Inst.C.E. Sir Leopold made an initial reference to the history of civil aerodromes, and remarked that even now the pro gress that had been made in aerodrome construction in this country had been very slow and did not bear com parison with that achieved in some other countries. Since the opening of Croydon as a civil airport the construction of aerodromes had been started in various parts of the countrv, and by 1934 there were forty-three licensed for public use, ten of which had customs facilities. In addi tion to these, there were thirty-six privately owned aero dromes. Of the public aerodromes, fifteen belonged to munici palities, and many had applied to the Aerodromes Ad visory Board for advice. Suitable aerodrome sites were, however, becoming more aird more difficult to acquire, and no time should be lost in the selection of a suit able site. Sir Leopold then gave a short summary of the early air services emanating from and devc'oped in this country, followed by a list of those operating at the peak period last year. Types of aerodromes might, he said, be considered under three main types : Large terminal airports, municipal aero dromes, and private aerodromes. The first-named should have facilities for dealing with the largest aeroplanes, and should be situated as close as possible to the town con cerned. The second type would be similar except that it would not be necessary to provide facilities for customs or police, and the layout generally would be on a less elaborate scale. The provision, however, of a safe and suitable landing ground at all times and in all conditions of weather was of the first importance in this as in all types of aerodromes; it was also important to provide rapid communication with all parts of the city which was served. As the foregoing types of aerodromes were intended for the use of the public they would require to obtain an Air Ministry licence, as would private aero dromes where facilities were provided for instruction in flying and for privately owned aircraft, or where manu facturers tested their machines. Private aerodromes tor personal use, constructed on the owner's own land, did not require to be licensed. hooking Ahead Besides these recognised types it might be that in the near future, with the development of Autogiros or similar machines, a comparatively small area of land might be made available near the centres of large towns. There had also been proposals for utilising the roofs of large buildings. The first and principal requirement for all types of aero dromes was the provision of a suitable site capable of being so developed that it would provide a safe landing and taking-off ground at any time during the day or night and under all weather conditions, for the types of aeroplanes which might now or in the future be expected to land there. It should be situated as near as possible to the centre of the town, but not on the side opposite to that iom wnich. the prevailing wind blew Aerodromes hih „ not be situated at the foot of. or near. hills or off t- "ro!inc' on account of induced air currents and general ructions. Buildings such as tall chimneys and church tP' reR 'hould be given as wide a berth as possible, and aero<h"ome should be located at least a mile away from overhead high tension cable lines, unless such obstructions can be placed underground. An obstruction diminished the available space for landing and taking-off by a distance equal to ten times its own height, measured from the foot of the obstruction. An important factor was that it should be so situated that there existed or could be provided a rapid means of transport to the town. The dimensions of an aerodrome to be used by the largest aircraft should not be less than 800 yards in all directions, and it would be advisable, Li possible, to pur chase land to allow for 1,000 to 1,200 yards. Only in very exceptional circumstances would tl > Air Ministry license a site affording a clear run of less than 600 yards in any direction. For small aeroplanes a site measuring 400 yards in all directions sufficed, provided the ground outside and within 100 yards of the perimeter of the aerodrome con tained no obstruction higher than the average three foot fence or hedge. Drainage Problems A large number of engineering problems also had to be considered before the final selection of a site could be made. Gradients should not be excessive—the average should not exceed 1 in 50 On the ether hand, too flat a site might present drainage problems. This was a very important consideration. Large areas needed to be drained with a much quicker run-off than was necessary for agricultural purposes. The system generally employed was to use surface intercepting drains of the French type, feeding into main collector drains. It had been found that land which, at first sight, appeared impossible could be satis factorily dealt with at a reasonable cost. French drains were usually placed at the edges of aprons to connect with the main system. The main requirements of a good surfacj for an aero drome were that: (a) It should be hard enough to carry the weight of machines. The Air Ministry had laid down that a landing field must be capable of withstanding a rolling pressure of two tons per square foot, and the test they recommend is to drive a fully laden 3-ton lorry slowly across the field, (b) It should be soft and resilient enough, (c) It should be as cheap as possible to lay and be capable of quick and easy repair, (d) It must be free from dust and be non-sticking and non-skidding. Gener ally speaking, the grasses used should be tough hard-wear ing, short grasses with creeping root systems. Although a well-maintained grass field would provide a suitable landing ground, an artificial surface might have to be provided, at any rate for a portion of the landing ground, as was done in America and elsewhere. Various types of surface had been used in the construction of run ways, the type adopted at any particular site usually being dependent on local conditions of labour and materials available. Several examples of asphaltic concrete i-n- ways had been constructed, and this material appeared to give better results, while being somewmat cheaper. Good results had been obtained with "oiled earth" runways, which was a much cheaper form of construction. It con sisted of mixing the natural earth, or ashes, with ordinary asphaltic road oils either in a mixing machine or in situ. A good, fairly hard surface was obtained. The surface was impervious to water and had to be drained in a similar manner to all hard surfaced areas. An important feature in the development of a large airport was to prepare a lay-out plan of the area to allow for future development. Drainage and grading operations should then be conducted to conform with this lay-out. Building requirements were entirely dependent on the function of the aerodrome. Sir Leopold said that
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
