Патент USA US2132599код для вставки
Oct. 11, 1938. K.~BAUMANN Er AL I 2,132,599 LANDING MEANS FOR AIRCRAFT Filed Jan. 3l, 1936 \ \ @Eff/vee Fae mer/mL #www W W nœoßemf ' nemvsmrrfe Patented Oct. 11, 1938 ,d . 2,132,599: TS Urrea N met ` Aoi-‘FICE - 2.132.599 » »LANDING MEANS Foa AiRcRArT' _Karl Baumann, BaseL‘ïand Armin Ettinger, Birs-` felden, near Basel, ‘Switzerland¿> i `Application> January 31, 1936, _Serial No. 671,712.0-` j ï In Switzerland December 23, 1935 ~ 5 claims. iol.’ 2501-11) ' ` yThis invention ‘relates to a Inetl‘iod"` of and means forassisting the landing of airplanes. Y ` To assist the landing of aircraft when there is little or no visibility it is necessary for the pilot may be adapted as `desired to local landing con ditions. - " » `"The invention accordingly consists in the fact thatithe output potential of the receiver on the 5 proper direction for landing and that he is gliding matically, from >a certain point of approach of the .down along a path suitable for the particular landing airplane, theV ampliñcation of the receiver ` `landing ground concerned, and for this purpose va in respect of thevertical- navigation, in such fash method has already been proposed which makes ion that the pilot, in» order to maintain constant lO'use of different levels in the radiation ñeld of the intensity of the signals received, is compelled 10 ‘5 `tor be 'notified> in some form that he is in the - ground for thev horizontal navigation varies auto- a `transmitting aerial' or aerial combination, a transmitter being‘provided on the ground and a receiver in the airplane see for instance:> E. Kra to descend at an angle which intersects the levels infthe ñeld lof the receiving aerial in respect of mar;` The present state in the art of blind land loïing of `airplanes using ultra-short waves in Eu ropa. Proc. I. R. E., vol. 23, page' 1171, October 1935. The invention will* now be described more fully The primary disadvantages associated with this . arrangement consist in the ñrst place in the fact 20 that the more sensitive of the two apparatus, viz.,` the receiver, is located `on the airplane, so that there are considerable interferenceslin the reception, `due chiefly to the ignition _system ofA the engine.` To overcome these interferences the 25 transmission output must accordingly be-very high. Secondly, there is no possibility of con trolling the glide of` theaircraft during the land ing operation on the ground. - f A the vertical navigation.` ’ ` - , Y _ with reference to theaocompanying drawing, in 15 which` ‘ ' » Y ‘ Fig. l indicates diagrammatically Vthe landing operation in'accordance with the invention, Fig. 2 is a circuit diagram relating to the trans mission of the signals. 20 Fig. 3" is a diagrammaticv plan view` of the di~ rectional aerial for the receiver for horizontal navigation. ` ‘ A ~ Figl 4 is a diagrammatic view of the receiver for horizontal navigation and the change-over 25 device interposed between it and the directional aerial. ` Fig. 5 is a diagrammatic view hereinafter re To avoid the disadvantages aforesaid it'has, ferred to. i 30 therefore, also been proposed to locate the trans . For determining the horizontal direction of ap- 3o mitter on the aircraft and to provide the receiveA proach towards the landing ground there are ing system on the ground, the landing glide of the employed the directional characteristics of two aircraft being determined by a level of the re~ ‘ crossed` receiving loops R1 and R2. Fig. 3 shows ceiving aerial system. 'IA‘he receiving ‘apparatus these two' loops Rl'and R2 with their horizontal 35 controls automatically a‘ .transmitter> non the directional characteristics in plan. The circles 35 ground, and the controlA signals received by the ` in dotted lines represent the receiving character- » aircraft, for example by means of a normal re istie of the loop R1 and the circles in full lines ceiver, are made noticeable‘to the pilot either acoustically or optically. the receiving characteristic of the loop R2. The mined by the signals received, i. e., in which the landing ñeld in ,the direction> PO, which line of output potentials of . the two loops, with equal 40 `Now‘inthis latter method, in which‘the exact construction of the loops, are alike when a wave 40 horizontal and vertical line of movement of the arrives .in the direction PO which is the direction aircraft when approaching the ground is deter-" ofrlanding.V If now an airplane approaching the gliding path is defined as level in the field of the ‘ direction divides the angle between the planes of 45 receiving aerial arrangement provided on the the two loops into two equal angles, transmits by 45 ground, it has been found that the glide becomes means of atransmitter a continuous tone, then very ilat towards the end. In consequence there is always a certain danger'in association with are alike. AIf there is a deviation from the proper 50 comparatively high points or obstacles situated in the output potentials created inthe two loops landing direction towards the> right,` the output potential of the one loop, owing to the transmis- 50 sion of a continuous tone by the ultra-short wave transmitter on the airplane, is greater than that It is the object of the invention, therefore, to of the other loop. _» Upon deviation towards the provide a method and means by which the line left the position is exactly vice versa. For the 55 followed by the airplane when gliding to' earth s purpose of obtaininga greater relative sensitivity 55 ` ` the line of ñight in the immediate vicinity of the aerodrome. Y . » p l l2,132,599 2 to fluctuations in the direction the loops may be fashion that the instrument actuated by the disposed at an angle which is greater than 90°. answer-back continues to> show the same extent The output of the two loops is applied alternately of movement, in which case he glides down to the by means of a mechanically operated switch-over device S (Fig. 4) to a receiver U, in such fashion that the period of connection varies in respect of the two loops. The mechanically operated The two modulation tones (for horizontal and vertical navigation) are separated by low-fre switch-over device S may be driven by a motor adapted to connect the movable pair of switch members alternately with the terminals of the two loops R1 and R2. The direct current result ground along the prescribed landing curve. quency filter chains in the receiver on board the airplane. It is also possible to provide .at a suitable point a receiver combined with an aerial arrangement, 10 which has such a vertical characteristic, -that ' ing after rectification of the low-frequency output Y Vwhen passed over bythe ultra-short wave trans of the said receiver is employedV to control the `mitter transmitting on board the aircraft de velops for a brief interval an output voltage key amplitude of `a tone produced by a tone genera tor, the frequency of which differs» from,r >>the Aing a'thirdV tone generator and applying this` low 15 modulating frequency of the ultra-short wave frequency voltage as modulation frequency to the aerodrome transmitter. This modulation fre transmitter on the airplane.-`v Y quency, when» received in the airplane provides This locally generated frequency, which is de pendent as regards amplitude on the output of.r indication that landing should be commenced 20 ’ the said receiver,’is then applied as modulation v(marker signal). Fig. 5 illustrates» diagrammatically the methodv tothe aerodrome transmitter,L Thesignalsof thev aerodrome transmitter may be received by the described in the foregoing. Hi represents the aircraft with a normal long-wave receiver. If the ultra-short wave> transmitter in the aircraft, I direction of the airplane exactly coincides with the normal» long Wave operating receiver with the landing direction, the two loops'r will be actedv automatic sound-volume control in the aircraft, 25 upon> equally by the ultra-short wave transmitter K are Ythe low frequency filter chains by means of on the airplane. » ' , 25 which the answer-back signals ofthe aerodrome , Upon the changingover of the loops there` is then no jump in the sound intensity at the out put of the receiver U. The modulation of the aerodrome transmitter corresponds, therefore, with acontinuous tone without jumpin intensity, and indicates to >the pilot,_who receivesthe sig nals with _the long wave4 apparatus, that he is 3.57 iiying inthe correct- direction of approach. If his course deviates from the mid-position towards the right, the one loop isacted upon bythe ultra shortwavetransmitter'to a greater extent than theA other, and the one signal, for‘exam'ple the 40. shorter one, will be louder thanthe other. Upon deviationV towardsthe left the longer signal will transmitter modulated with different sounds are separated,„L and M are the indicating means for the horizontal and1vertical navigation, N rep 30 resents the receiver- for the vertical navigation, R the low frequency output rectifier for the ver ticalr navigation, Trthe loop system for the hori zontal navigation, S the changeover device for the loops, U the receiver for the horizontal-'naviga 35 tion, and Weis ,theaerodrome operating trans mitter. , . TheV method asdescr-ibed up to now constitutes in all detailspart of the- known art, and no claim whatsoever- is made to the same per se. 40 Referring now to` Fig. 1, the curvesV lY to 5 indi- ‘ be `louder than the ‘shorter one. , In this way it cate different levels in the field of the receiving is possible to distinguish between the two sides. aerial V. ’ The dilîerent curves correspond with different valuesof the» intensity of the field. 'I'he fv aerialv arrangement on the ground isA acted upon> top curve indicates the greatest and the bottom by the waves transmitted bythe ultra-short wave curve the lowest intensity of the field. For the` vertical navigation; another receiving transmitter on the airplane. An exampleï for such anarrangement ofantennassee for instance Diamond and Dunmore: A radio beacon .and re _ ceiving system for vblind landing of aircraft. Proc. I._ R. E.,l vol. 19, Fig. ’7, page 596, April 1931. There'is described an arrangementfor the trans mittingcase', but allv concerning the vertical characteristic holds also` for the receiving case. l The glide pathislaid down as anequalintensity linein the vertical characteristic of the receiving antenna arrangement. The direct current of the In landing without the regulation provided for by the invention the line of flight would coincide with'one of the curves l to 5. If Vnow the ampli fication of the receiver on the ground for the 50 Verticalv navigation is increased from .a certain point of> approach, such as A, which corresponds with the distance Xfrom the aerial system for the vertical navigation, the pilot, in order that the’ outputofî the ground receiver for the verti 55 cal navigation, and accordingly the intensity of Y Y the verticalnavigation signals transmitted to the low-.frequently Output of this receiver on the ' airplane, remain-constant, 'must steer the ma ground controlsthe amplitude of` a second sound> chine so as to intersect thecurves I to 5, for eX generator, the frequency of which differs from an'iple at ther points A; B, C, D‘and E, so that 60 that of the sound generator previously. referred to. ` proceeding from the point A the angle of descentv ~ The output of, this second so_und generator like- ' becomes steeper. This` method maybest be Vexplained in con- H wise modulates the aerodrome transmitter. For thev purposeY of explanation it- is assumed . junction with a particular formv of embodiment: Y The ultra-short wave transmitter on the airplane 65 kthat an airplane is> flying at a certain altitude :ln` the direction ofk landing. The output potential> acts on the ground receiversfo-r the marker sig nal,V the horizontal navigation and the vertical navigation. The aerial system of the receiver> for the horizontalnavigation should be such that notifledbackÑ to the airplane. ' If the movementon thepart'of aninstrument ` its output potential depends primarily on the dis tance of> the -airplane transmitter. The 'aero in the’airplane actuated bythe answer-back sig nal reaches a certain Yvalue which is individualto- drome receiver for the vertical navigation oper the.` particular aerodrome concerned, the pilotl ates without regulation up to the moment when commences to descend and, whilst maintaining the airplane with the ultra-short wave trans- . of the ground receiver continuously increases, and. in accordance with the method above described is 75. ¿the -landing,direction~,'steers his-machine in such - mittervv on board- transmittingv flies over the an- 75 211232,599': tenna arrangement of ftheïinarker signal- receiver and so actuates‘the‘fmarker signalywhichat the same time indicates by its location the nearest obstacle in 4the" direction of4 landing in the’vicin ` ityìof‘the aerodrome. ‘Up to this point, therefore, the airplane‘indescending follows a normal level must be of such a construction, that the contacts of the aerial systeinin vrespect of the vertical navigation. » - ‘ ’ " ‘ ‘ ` 3 the ampliñcation of the receiver for the vertical navigation becomes all the greater the nearer the aircraft approaches the receiver` for horizontal navigation, thus giving a glide path steeper than without regulation. It is clear, that `the relay 6 are fixed in their position, when ‘once the two up per are opened and the two lower ones are closed, ’ «When the airplane .with> the ultra-short wave because the current through the coil of relay 6 transmitter transmitting on 4board passes over the antenna system@ connected with the receiver" for themarker signal the antenna yields an in-> put voltage to the `marker signal receiver. The output .voltage of `this' receiver is only present ‘when the transmitter‘on boardvpenetrates thev vertical lobe of the vertical diagram of the asso ciated antenna arrangement `of‘ the marker sig nal receiver. This` output.. voltage switches on automatically by means of a‘relay the regulation flows only during the time, when the airplane with the’ultra-short wave transmitter transmit ting on board isftransversing the vertical lobe of the diagram of the marker signal antenna sys tem. Such relays are known (Impulse relays). When the landing is made the contacts must be 151 brought back to their initial position. This can be eiïected by giving an impulse over the coil of thel‘relay given Aby the wireless operator of the aerodrome'. ‘ » ` ' » 'A » :of amplification ofthe ground: receiver in respect If theantenna system of the marker signal- re of 'the `vertical navigation.4 The' voltage .regulat-` ceiver is not passed at exactly Vthe correct alti ing the amplification of the receiver for the ver tude, then the voltage tapped at `potentiometer tical navigation is deducted from the output of ‘I does not exactly compensate the voltage tapped the‘receiver for the horizontal navigation. 'I‘his at potentiometer 8. Thus a jump occurs in the is; regulation voltage is substantially'proportional to amplification of the tube 3 upon the switching Vthe >distance of the airplane from the receiver for over of the relay 6. From the answer-back mes horizontal navigation. l‘In the receiver for theV verticali‘iavigation` are provided one or `more sage received by' the-.pilot `the latter- is able to >whether the machine was flying over tubes having-a variable and adjustable amplifica-- ascertain the marker signal receiver too high or too low. ` tion factor. »The regulation voltage deducted A certain allowance may nevertheless be made in from> the output of the receiver for horizontal this connection whilst still permitting of a safe navigation is applied‘to. the regulation grids of these.> tubes thus alîe’cting‘. the amplification of theV receiver for vertical navigation in proportion ofthe distance of the ultra-short wave transmit terv on board the airplane: to the' antenna system of the receiver for horizontal navigation;` ' In Fig. 2, I is the receiver, which’can be of the normal superheterodyne type, with its antenna ‘ system having a vertical characteristic with the main lobe directed upwards.` l 2 is the receiver for the horizontal ‘ navigation with its. two crossed loops.` 3 is a variable high-frequency` pentode landing. 25 This allowance may be marked on the vertical navigation instrument inthe airplane. The pilot then merely `requires to navigate the machine vertically in such fashion upon landing that the diiîerent movement of the instrument remains constant. «i ‘ i » i The angle of the glide pathmay be adjusted by means of the potentiometer 1 applying a more or less greater part of the-output voltage of the 40 receiver for'horizontal navigation as regulation voltage to the receiver for vertical navigation, thus making the angle of the glide path to follow provided >for instance as .a stage in the intermedi i ate frequency amplifier ‘of the receiver for the more or less steep. By means of resistance 5 it isV possible to vary the length of the regulated 45 vertical navigation or as` an input stage of this receiver. In the first case the grid circuit ¿lisA path. If for instance the resistance 5 is set at tuned tothe intermediate frequency of the re-_ ceiver, in the second case to the frequency of the ultra-short Vwave transmitter in the airplane. With the aid of resistance 5 the working point of the tube 3 is set at a point of low ampliñcation factor, the resistance 5 giving a fixed bias to the regulation grid of this tube, when the upper two contacts of relay 6 are closed. So long as the marker signal receiver has no input voltage ap plied thereto due from the transmitter on board the airplane the tube works constantly at this ` point of its characteristic. When iiying over the 60 antenna system of the marker signal receiver, however, the relay 6, actuated by the output volt age of the marker signal receiver, by closing the two lower contacts and opening the two upper ones, applies a part of the output voltage of the 65 horizontal navigation voltage, which is tapped at the potentiometer 8, to the regulation grid of the tube 3 of the vertical navigation receiver. The potentiometer is so adjusted, that, when the `marker signal receiver is flown over at the cor 70 ` rect altitude, the potential tapped by way of the potentiometer 1 is just compensated, so that upon the switching over of the relay 6 the amplifica cation of the tube 3 is not altered. After the receiver I is overflown the regulation 75 commences to take effect, in -such fashion that a-value `such that only a small voltage increase puts the amplification of the tube 3 to its highest possible value, then the last part ofthe glide path is not regulated, because a further increase of 50 the regulation voltage does not increase further the .ampliñcation of tube 3. Since the horizontal navigation is performed according to the method in which in a certain direction the signals supple ment each other to form a steady line, care must 55 be taken in the output of the horizontal naviga tion receiver that in the case of small deviations from the exact horizontal path the regulating potential corresponds with the mean value of the two signals, which may be accomplished by a 60 netwo-rk‘with corresponding time constant. What we claim as new and desire to secure by Letters Patent is: 1. In means for assisting the landing of air craft, means for transmitting signals from the 65 aircraft, directionally sensitive aerials on the ground by which said signals are received, means for establishing answer-back signals from ground to aircraft, a vertical navigation receiver on the ground and connected with one of said aerials, 70 and means including a horizontal navigation re ceiver connected to another of said aerials for so varying automatically from a predetermined point of approach of the aircraft the ampliñca tion of said vertical navigation receiver to vary 75 22132;,599? onwtheeaircraftï indicating ¿the horizontal andver that the pilot in order to¢»mainta~infa -constant; tical navígationlnecessary inaccordancezwith the intensity of reception-of the answer-_back signals'ì 4.. In-- av means o forgaaissisting;.theI landing o of -air is compelled-to descend atfan, angle intersect-ing;v 5 the levels in thefield ofthe receiver for the ver-Í craft; aftransmitter on boardftheaircraft; direc tionallyfsensitive ,aerials 'onthe' ground; a vertical ticalmavigationv a characteristic ofg’the answer-backesignals so: signals,»,receivedi ' Y f‘ ' Y ' " ' 2,.A In a ,means-'for' .assisting the landing; of, air-l ,navigation receiver-»connected with, one >of saidv craft, ’a transmitterçon board the ,'aircraft', a1 ver-` aerials, a horizontal navigation receiver ’and a; marker» signal` receiver ' connectedA with others;` of tical navigation receiver and a directionally sen sitive aerial thereforlocated‘ on the ground; aY said-aerials, themarker signal receiver`V being ac tuatedby signals-transmitted bythe aircraftwhen; horizontal navigation receiver anda direction ally sensitive aerial therefor, _said receivers; being- the aircraft. i‘lies, overf-thesame, an; ansWer-back-~` constructed to receive signals transmitted from' signal transmitting means, 'meansl operatively theV aircraft, an, aerodrome transmitter and. an, connectingsaidi receivers =with one another and with saidianswer-back signal: transmitting means> 15 E aerial'therefor- for transmitting answer-backl sig nals to the aircraft; operative means connecting for transmitting answer-back signals :to-the air craft automatically, _ag receiver; onI thev aircraft; saidvvertical navigationY receiver and said hori zontal navigation receiver respectively tosaid for receiving said; answer-back; signals, a relay. operatively connectedwith said'marker signal retaerodrome transmitter for affecting a character istic'jofçthe ans_Wer-back- transmission, a receiver ceiver for, energization. by, the output> voltage 2.0 thereof; said: relay,”including- ,means> for coupling ontheaircraft forreceiving the answer-back sig nais, meansfor varying theY ampliñcationof said' the vertical navigation receiver` with the outputy vertical navigation receiver in accordance with. circuit; of the-,horizontal navigation receiver, and’ the output-.of the‘horizontal navigation receiver,-r means for adjusting the effective actionof, said, horizontal navigation. receiverf.~ 2,57; and» instruments on the aircraft forindicating 5'. Ina means forassistingçthe„landingof air- > the horizontal and vertical navigation necessary-~ Y in view-of- the signals received; , o 3; In Ia means forïassisting the lancling'oi:` air craft, a transmitter'on board the aircraft, di rectionallysensitive aerialsfon theground,l a verticalnavigation receiver, a horizontal/navigationV receiver and- a~ marker signal receiver; each'fre ceiver being- connectedto ay diiîeren-t one of saidfv aerials, the said receivers `being adapted to re-> ¿.¿ceive signals transmitted by. the- aircraft,- an answer-back signal transmitter, operating con nections between said marker signal receiver and said' horizontal and said vertical navigation re ceivers,V operating connections between saidfhori zontal and >vertical' navigation receivers respec tiveiyand rsaid answer-back transmitter for af fecting a characteristic of- transmissionl ofu an sWer-back signals to theV aircraft»V automatically, a receiver on the-aircraft-for receiving the said eli), answer-back signals, a relay operatively connect edfwith said marker signal receiver'for energiza tion bythe output voltage thereof', said; relay in cludingfmeans,for-coupling the vertical naviga tion receiver with the output circuit of the hori zontal navigation receiver so `that the output po tential thereof` Will act on the amplification Yof the vertical navigation receiver, andjinstruments,` , 25. craft,-, a, transmitter;l on board; the' aircraft, di- ` rectionallyv sensitive» aerials on the> ground,Y a ` verticalV navigation _l receiver connected'- With one of said .aerials and having an intensity regulating 30, tube, a` horizontal. navigation receiver and a> marker.I signal receiver-connectedwith others of said aerials, said marker signal receiver being actuated in response to. signalstransmitted by the .aircraft when the - latter flies ¿over said mark 3,5v er signal- receiver, ran answer-back` 'signal trans mitter, operating»connectionsbetween said mark; er signal receiver.' and. saidhorizontal; andV said vertical navigation receivers respectively and, said answer-back signal transmitter` and includ ing-means to couplevthe intensity regulating tube 4,0. with. the output circuit of thehorizontal naviga tion receiver, a„ variable‘resistance acting inthe circuit ofthe tube ofçthe vertical navigation re- ' ceiver for varying the working. point of the'char 45 acteristic 'of'saidt tube, andiinstruments onthe. aircraft indicating the horizontal and vertical navigation necessary, in, accordancev withV the signals received. v ' KARL BAUMANN. ARMIN.: ETTINGER.