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Aviation History
1964
1964 - 1071.PDF
606 FUGHT InterncrtKHw/, 16 fail ly ,4 AIR COMMERCE Vi V2 AND ALL THAT... the one-engine-out determination of Vr—the former producing a minimum lift-off speed of 1.1 Vmu and the latter 1.05 Vmu. However, as engine-out Vmu is discontinued and as all these qualifications are somewhat confusing, I have omitted them from the definition. This follows the ICAO PAMC rather than SR 422b or BCAR which again introduce slightly different parameters because of the varying concepts of Vs, Vms and Vsig. Definitions:— (7) The Rotation Speed (Vr) is the speed at which, in both the all-engines-operating and the one-engine-out conditions, it is recommended that the fuselage sheald be rotated so that the aircraft lifts off at a speed not less than 1.12 Vmu and attains a speed of not less than V2mm at the end of the take-off distance available (i.e., the 35ft point). Vr must not be less than Vj or 1.05 Vmca. (PAMC 6.2.5. Doc. 8283, page 30; SR 422b 4T 114(e);BCARD2.8.3.2.) (5) The Lift-off Speed (Viot) is the speed at which the aircraft first becomes airborne. (PAMC 6.2.6. Doc. 8283, page 30- SR 422b 4T114(f).) This group of "transitional speeds" (Vr, Vmu, Viof, V2min) are designed to take us safely from the ground environment to the airborne environment, this being assumed to be fully attained at a height of 35ft. They all take credit for ground effect where this is present. Speeds after 35ft (including the initial climb-out speed, V2) take no credit for ground effect. But of these another time. (PAMC 6.2.6. Doc. 8283, page 3; SR 442b 4T114(f).) LONDON'S SECOND, THIRD AND FOURTH AIRPORTS IT is ironic that Britain, where the idea of a political oppositionparty originated, has failed so far to extend the concept tocope with the problems of the technological era. In the United States, the administration's experts are "opposed" by com- mittees of the Senate and House of Representatives, lavishly pro- vided with other experts as advisers. If we had such a system, the "Q3" plan and the atomic power station programme, for example, might have been terminated at far earlier stages. The report on London's third airport is written by Government departments, to some extent defending their decision to continue expenditure at Stansted, a matter raised by the Select Committee on Estimates in 1961; and therefore it deserves especially close scrutiny. It is an extremely well marshalled document, and in- evitably much of the material studied would not be included in the final report. However, in its published form, a number of questions remain at best only partially answered. The last similar exercise, siting London's second airport at Gat- wick, was not a success. BEA, who had an important influence on this choice, moved in enthusiastically enough; but soon decided to move out again. Foreign airlines refused to move there at all. In view of the amount of public money spent on it, taxpayers will be interested to read that, apart from its role as a diversionary airport, Gatwick was planned to handle "the seasonal overflow, and some charter operations." The committee appears to have added the word "seasonal" into the Minister's observations dated December 20, 1961. The committee's arithmetical calculations assume that Gatwick will be fully utilized, and obviously this means serving Continental destinations to the south and south-east. Thus, it should have inves- tigated what must be done to make the airport acceptable to the airlines; this can affect the timing of investment at Stansted. The low utilization of the 12min rail link at Brussels—less than 40 per cent of the passengers used it in 1962—reinforces the sus- picion that the basic mistake at Gatwick was to rely on a rail link. If this is so, the Crawley motorway programme may need to be accelerated, and there may be a case for terminating it nearer Central London. Major works would be needed to convert Gat- wick into a road-served airport. Unless the foreign airlines are convinced that access to Gatwick and Stansted is comparable with that to Heathrow, their Governments may be tempted to banish our companies to obscure airports in their countries. For other reasons, mainly the high capital and running costs, and the comparatively light traffic generated by even a busy airport, the committee "could not treat the availability of rail transport as a determining factor in the choice of London's third airport." It should not have been in the case of London's second airport, either. Another disappointing finding is that Gatwick's second runway will increase the airport capacity by only eight movements, to a total of 40 per hour. The 1970 forecasts are:— Total forHeathrow Gatwick London (1) (3) Air transport movements at the standard busy rateAnnual movements Passengers 63 229.000 (5m 29 50.000 2.4m area92 279.000 17.4m Gatwick's present traffic is highly seasonal, so that the capital cost per passenger handled is even more disproportionate. The reason for this melancholy state of affairs is that "Gatwick has room for only one sequencing area, because of its position in relation to Heathrow" Flight International, April 2, page 486 for map of proposed three airport airway system). Why was this not foreseen ? In any event, this is the type of problem that is "insur- mountable" to the experts who created it; but somehow seems to dissolve when new blood is injected—or even when a determined non-expert insists that a solution be found. Another factor, basic to the committee's conclusions, that may belong to the same category, is the assumption that each runway in the London area has a sustainable hourly capacity of 32 move- ments, half of which are landings. "Some American airports achieve higher movement rates than this by means of more spacious runway layouts; but comparison is difficult since so many factors are involved, such as the frequency of poor weather." London's traffic is much more concentrated into the summer months than is usual in America. Are British summers really worse than American winters ? Or should we investigate fully how the Americans achieve their higher utilizations? On Good Friday 1964, Kennedy Inter- national handled 1,397 movements, a 24hr average only slightly below the committee's assumed peak rate in 1974. If the extremely precise approach evolved as a by-product of the Autoland programme does not eliminate the need for a really spacious layout, we still might have time to put the runways the right distance apart at Gatwick, let alone Stansted. The committee did assume independent use of the parallel runways at Heathrow- resulting from improvements in air traffic control techniques— otherwise the sustainable capacity could not have risen from the present 48 per hour to 64. Some outside authorities believe that the assumed 33 per cent improvement is too conservative and that a 100 per cent increase is possible. All these points are concerned with the timing of the project, rather than the choice of Stansted, with which it is difficult to quarrel. One remaining doubt is whether the location of London's fourth airport affects that of the third. The committee recommends that the question should be looked at again in about five years' time, when it can be foreseen whether helicopters, or V/STOL aircraft will- be commercially operable. The feasible sites due east of London would interfere with the deve- lopment of Southend, which in 1962 had a higher standard busy rate than Gatwick; of course, some might feel that Southend is London's third airport! An "insurmountable" problem in this area is that the War Office regards the sand on the Shoeburyness range as irreplaceable, be- cause it enables shells to be recovered intact for examination. Doubt- less, the new howitzer shells used so effectively during the Sudan campaign of 1898 were developed there. A thorny problem left unanswered by the committee is the divi- sion of traffic between the airports. BEA and BOAC have a simple solution; they wish to run all their services from Heathrow; trie foreign airlines would move to Gatwick and Stansted. The cor- porations have their bases at Heathrow, and 15-20 per cent of their traffic "interlines" there, principally to and from the domesuc routes. However, the committee finds that in the long-term Heai ri- row cannot remain omnidirectional, so that the corporations' so!i- Concluicd at foot of page < U
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