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Aviation History
1937
1937 - 1358.PDF
5i2 FLIGHT. MAY 20, 1937. In this case the pronoun simplifies the narrative and is not used to suggest that I did either the flying or the operat ing), entered the 60-metre ceiling almost before Purley Way had been crossed, and worked up to an operating height of 2,500 ft., where there was something resembling an horizon between two cloud layers, and the ground could be seen in occasional glimpses. Mr. Brownrigg let out the trailing aerial and tested his set with the usual report of height, speed and destination. Later he was to save other people a lot of trouble and show himself as the really in telligent operator by listening-in to other machines and to the broadcast weather reports. Some operators con sistently ask for such information as can easily be picked up in this way. Knowing the route so well, this team do not often ask for fixes either. When we should have been crossing the English coast in each direction, bearings were demanded from both Croydon and Lympne, and our position was approximately checked. In one case the two bearings were 140 and 241 (second class) and in the other 147 and 213. This information was all that was needed by Mr. Duggan to know his position, and it is significant that before these bearings were asked for during the return flight, and after a blind period of half an hour or so, I was asked to keep a look-out for the coast in any break down below ; almost as I was asked I obtained a brief glimpse of a line of surf. With the weather fairly clear at Le Bourget we came in directly on a QTE of 322, and a final QDM of 161 to get an exact line on the aerodrome. When the ceiling is really low and/or the visibility very poor a version of the time-honoured Z.Z. system is still used, though the V.H.F. system over there should by now be in working order—or nearly so; the last time I saw their beacon it had been experimentally laid out, after initial failures, in a field some half a mile or more from the landing area. The D/F system of approach involves the use of two gonio huts on a line towards the longest run of the aerodrome, which lies approximately north and south and is about a mile and a quarter in length. An approaching machine is flown away beyond the aerodrome in a southerly direction at a height of about 300 m. and is then brought in on a QDM of 13 deg. When the first gonio hut is crossed the "motors over" is given, and the pilot then flies in on the same bearing towards the second hut (which is on the aerodrome boundary), while losing height with the knowledge that he it. only a mile or two from the aerodrome. We were satis fied on this occasion to receive the usual weather report with a millibar setting for the sensitive altimeter. In on Bearings The return journey was a trifle more eventful, though not in the sense of being in any way difficult. After cross ing the French coast (according to calculations—we never saw it) the Croydon weather report read: QBA 2 km , QBB 230 m. 9/10, 1,013.4 mbs. , which, being interpreted, meant that visibility was 2 kilometres, the sky was almost completely obscured with cloud having its base at 230 metres, and the barometric pressure (for altimeter correc tion) was 1,013.4 millibars. Not too good, but safe enough for a properly equipped machine. Later, the cloud-base descended, as it happened. When almost ready to enter the controlled zone we were told that our QGP, or landing turn, was No. 2—another machine was just coming in. A moment later we were asked to change over, to controlled-zone frequency and PROTECTION THE " Fescol " process for buildiug-up and protection of metals has been tested and approved by the Air Ministry, Admiralty and War Office, and is now in wide and general use. The three metals most commonly deposited by the process are nickel, chromium and cadmium, and of these chromium has the widest application to new construction, due to its numerous useful qualities and the variations possible in hardness and thickness of deposit. This special process can be used for producing a bright gathered that we could come in. Not so, however; the fact was that there was so much congestion on the " out side '' air that the zone equipment and operator had to attend to us. After doing a few " rate three " turns some where over south of Westerham we got our QGP One and set off on a magnetic course of about 350 deg., receiving rapid-fire QDMs (magnetic courses to steer) from the Croy don control. These, as a matter of interest, were: 357, 358, 35L 353 ar»d 344. A moment later the "motors over" was received, the throttles were closed, and we saw the ground at 400 ft., just half a mile to the north east of the aerodrome. And so home. On that trip, for reasons outside their control, the crew were simply using the normal blind-flying instruments and two-way radio equipment. If any of the former had broken down, Mr. Duggan would still have had the others to go on with ; if his venturi had iced-up he would have had his manifold to provide the necessary depression for their operation. But if, by any chance, the transformer or any part of the radio system had failed we should have been helpless until such a time as Mr. Brownrigg had done some work on it. Essential Duplication My cry, in the interests of safer transport flying is, and has always been, for duplication in all essential equip ment. Not direct duplication, but the arrangement of equipment so that the failure of one item does not leave the pilot stranded in mid-air. On any other morning this machine of Wrightways would have been in as good a position as any. The V.H.F., or ultra-short-wave, receiv ing equipment is quite a separate affair, and any failure would have allowed the pilot to come into an equipped airport either on bearings or on the short-wave beam. Even so, it might not have been possible for him to navi gate with sufficient accuracy to get into the area of the beam signals if his medium-wave outfit had gone out of action, for instance, over the middle of the Channel. These remarks cast no slur on the manufacturers of radio equipment; even the very best can fail under the arduous conditions imposed in every-day air transport. A battery will not work for long, either, at steadily increasing pressure after the generator has broken down. Mr. Duggan's own idea, incidentally, is worthy of men tion. He considers that, in addition to the normal radio equipment and any short-wave receivers for approaching in poor visibility, every machine should have a cheap homing receiver, and that every airport and aerodrome should have a beacon which is constantly transmitting on some frequency which would not upset normal trans missions. If the airport radio operator then found that he was receiving no reply from any particular,machine, he could take it for granted that its radio had failed and transmit a message to say that he was arranging to keep the controlled zone clear for an approach and landing by this machine. This message would be picked up by,the operator on the auxiliary receiver. In the event of such rare failures it would be a small matter to arrange Turn One for the crew of the unfortunate machine, and the pilots of others would be the first to admit that a little waiting, much as they all hate it, would be in a very good cause. In any case, I repeat, every instrument and piece of navigational equipment in every transport machine should be complementary rather than vital. The failure of any single item should not mean a crisis. by DEPOSITION or decorative finish, a heavy deposit for subsequent grinding, a medium heavy deposit, or the special " Millichrome " finish. All these types of deposit can be used with advantage in air craft on such parts as spinners, oil pipes, stub axles, fuel-pump spindles, wing-locking, locating or hinge pins, and on many internal fittings. A folder giving details of method and uses of the process cess can be obtained from Fescol, Ltd., 101, Grosvenor Road, Westminster, London, S.W.i.
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