Title:
Antiaircraft fire control predictor
United States Patent 2378910


Abstract:
This invention relates to fire control directors, particularly of the anti-aircraft type, wherein the relative speed of the target is great. This application discloses in greater detail how the rate determining and introducing means disclosed in our prior application Serial No. 75,526, filed...



Inventors:
Chafee, Earl W.
Wittkuhns, Bruno A.
Application Number:
US16735837A
Publication Date:
06/26/1945
Filing Date:
10/05/1937
Assignee:
SPERRY GYROSCOPE CO INC
Primary Class:
Other Classes:
89/1.61, 235/412
International Classes:
F41G5/08
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Description:

This invention relates to fire control directors, particularly of the anti-aircraft type, wherein the relative speed of the target is great. This application discloses in greater detail how the rate determining and introducing means disclosed in our prior application Serial No. 75,526, filed April 21, 1936, now Patent No. 2,206,875, dated July 9, 1940, for Fire control devices, is applied in a complete modern director of the type disclosed in the prior patent to Earl W. Chafee, Hugh Murtagh and Shierfield G. Myers, No. 2,065,303, dated December 22, 1936, for Apparatus for control of gun fire.

The present application is therefore a continuation in part and further amplification of our aforesaid prior application.

A further object of the invention is to improve this system of fire control by adapting it for gliding targets by introducing a means for determining rate of change of altitude as well as the resolved x and y rates in a horizontal plane.

Referring to the drawings, illustrating the invention in diagrammatic form, Pigs. 1A and 1B are the two halves of a diagram showing the principal component parts of our invention, Fig. 1A being a substantial reproduction of Fig. 1A of Patent 2,065,303 and Fig. 1B showing the new rate means in place of the tachometers of the patent, plus the elevation rate device.

Fig. 2 is a diagrammatic view showing on a larger scale the mechanism for determining the target displacement during the time of flight of the shell, this figure being substantially the same as Fig. 5 of our aforesaid prior application.

eg. 3 is a plan view of one of the resolving mechanisms, being taken from the aforesaid prior patent.

Pig. d is a modification of the arrangement of Fig. 2 and is substantially the same as Fig. 3 of our prior application above referred to.

As explained in said prior patent, the sights ET and AT are maintained on the target by the elevation handwheel EH and the azimuth handwheel AH, the latter rotating the entire director and sights around fixed gear i. Altitude is also continuously fed into the machine from a height finder (not shown) through repeater motor 2.

The elevation angle Eo appears at Eo and Eo' on the coarse and fine indicators 23 and 23' and the azimuth angle Ao on coarse and fine indicators As and 'Ao', while the altitude Ho appears at dial Ho. Present horizontal range Ro is computed by the machine from the setting of three dimensional cam 10 which solves the equation Ro= HO tan Eo Said cam is positioned laterally by means of shaft 02 on which its support I is threaded, said shaft being turned from present range setting handle I3. The cam is also rotated in accordance with the altitude Ho from handwheel H which is turned until index I ' matches pointer 216. The lift of cam pin 19' rotates, through rack and pinion 20' and shafts 21' and 22, the pointers 22f and 223' on the elevation angle indicators Eo and Eo'. The cam is so laid out that with the correct height Ho and elevation angle Eo set into the machine, the rotation of the present range handle 10- 13 to match the pointers and indices of indicators Eo, Eo' will be a measure of the horizontal range Ro. The elevation angle Eo is set on the indices 20 and 22' of indicators Eo and 2o' from the handwheel EH, (which maintains the sight on Ig the target in elevation) through shafts 2 1 and 202, worms 208 and 290' arid step-up gearing 20C1.

Each pointer and index 282 and M3 reads on the same fixed dial or scale 224 and, similarly, pointer and index 223' and 23' read on the dial 224'.

-As the elevation angle changes, the operator of handle 13 preferably shifts to the range rate handle 24. This handwheel turns a dial 25 and. positions the shiftable member of a change speed device. As shown it positions a ball or balls 28 operating between a disc 27 turned from a constant speed motor 2B and a cylinder 21. Said cylinder operates the same shaft 9 as the handwheel 8 through a differential 8 J, and thus when handle S2 is set so that follow-the-pointer indicators Eo and Eo' stay matched, the correct rate of change of range has been set up. Similarly, as the altitude changes, the operator shifts to handle H' which positions the shiftable member 20' of similar variable speed device 29' which turns the same shaft 18' through differential IS' to position cam I8 rotationally by turning shaft I4. Shaft 30 not only positions the cam 10 axially, as explained, but also operates the cross shaft S0' and the shafts @2 and 88 driving present range into the present position resolving mechanism 3b , and also leading to the future mechanism 81.

Similarly the azimuth angles Ao are set in from the handwheel AH through shafts 83, 87 and 35, the latter being connected to the present mechanism .3 through shaft 31 and to the future mechanism through shaft 40. Said mechanisms are preferably superimposed and may be of Iden60 tical construction (see also Fig. 3). Each mechanism may comprise a large gear 4l having a spiral groove 42 in the upper face thereof. Said gear, in the case of the present mechanism, is turned from the range shafts 8O, 32. through a pinion 45. Superimposed thereon is a second concentrically mounted gear or plate 43 having a radial slot 44 therein which is rotated by a pinion 48 on the azimuth shaft 39. In said slot is slidably mounted a block 47 having pins and rollers 0o thereon, the lower roller engaging the spiral groove 42 and the upper pin 48 passing through slots 49 and 50 in-the superimposed slides 51 and 52. It will readily be seen that the angular position of block 47 about the center of rotation 0 of said gear is the azimuth angle Ao and the distance along the radius is the range Ro. Said plates or slides are constrained by slideways 53 and 54 to move at right angles to one another and it will readily be seen that the rectilinear displacements thereof represent the component displacements of the ground course of the target when the range gear or disc 41 is set in accordance with the present horizontal range and the azimuth gear or disc 43 is set in accordance with Ao. The differential 50' is for the purpose of preventing the range from being changed when only Ao is being changed by causing the two gears to move together under such conditions.

As above stated, the future resolving mechanism may be quite similar in construction but in this case the range gear 41' is rotated by a shaft 33 which is driven not only from the present range shaft 31' but also from a "range difference" motor 96 or change of range motor through a differential 97. Similarly the azimuth gear 43' is driven from shaft 40 which is rotated not only by the shaft 38 but also from the "azimuth difference" motor 98 through shafts 99 and 100 and differential 101. The vertically movable slide 52' in this instance is shown as turning a shaft 10 through rack and pinion II I. On said shaft is mounted one portion 86' of follow-up contacts 86-86'. Plate or slide 51', on the other hand, is shown as turning through similar rack and pinion II1' one portion 83' of follow-up contacts 83-83', the complementary contacts in each case being driven by one or the other of the range or azimuth difference motors as was more fully explained in the aforesaid patent.

Returning to the present resolving mechanism, the rates of movement of the two slides I1 and 62 are, of course, proportional to the rate of displacement of the target in the two component directions. To determine such rates, we actuate from the upi and down movements of slide 52, a shaft 56 through a rack and pinion connection 51; and through a similar connection 57' we operate the shaft 58 from the right and left movement of slide II.

Shafts 5I and 58 both are connected (the latter by way of shaft 83) to rate and displacement determining devices which constitute a marked improvement over the rate and displacement devices of said prior Patent 2,065,303, and which are substantially the same as shown in Fig. 5 of our aforesaid application, now Patent No. 2,206,875, reproduced herein as Fig. 2. The essential element of the device is a variable speed gear comprising a power driven disc, a radially adjustable ball carriage thereon, a cylinder driven thereby and a three arm differential, one arm of which is driven by displacement of the target along one axis, another arm of which is driven by the cylinder of the variable speed drive and the third arm of which is operatively connected to adjust the radial position of the ball carriage thereof. With such an arrangement, if the disc of the variable speed gear were to be driven at a constant speed (as is disc 2781 of Fig. 4 referred to hereinafter), the position of the ball carriage would be automatically adjusted, radially, on the disc so that when a state of equilibrium was reached, the distance of the ball carriage from the center of rotation of the disc would be a measure of the target's rate of displacement R along the chosen axis. In the arrangement of Fig. 2 an additional factor is introduced by varying the speed of rotation of disc 16 in accordance with the reciprocal of time of flight of the shell 1 T the two factors, R and being thus divided, as will be explained more in detail hereinafter, to give RT, the predicted displacement of the target during the flight of the 15 shell, this product being measured by the displacement of the ball carriage from the center of the disc. This interconnected variable speed gear and differential gear may be termed a self-adjusting variable speed gear. Other variable speed 20 drives, without the self-adjusting feature derived from the connection to the differential, are also employed where it is desired merely to convert a displacement into a rate of rotation, as will be described in connection with the introduction of 25 1 T and the wind correction.

As shown in Fig. 2, the x component of target displacement is supplied to the x prediction computing device by way of shaft 63 which drives one arm of wind correction differential 59, the middle or second arm of which is driven from roller 710 of wind correction variable speed gear 11 and 'the third arm of which drives one arm of a second differential 72 by way of shaft 189. The opposite or second arm of said differential 12 is driven by roller 73 of the prediction variable 40 speed gear 74, while the third arm radiall positions the ball or balls 75 of gear 74 on rotated disc 78. Said disc, as has been noted, is rotated at a variable speed from the roller 77 of a third variable speed gear 18, the radially adjustable 45 balls of which, driven from disc 80, are positioned by a cam pin 19, riding on cam T, whose lift is inversely proportional to the time of flight of the shell, . e., proportional to 1 50 The contour of cam T is computed from firing tables giving time of flight of a shell as a function of future or predicted horizontal range Rp 55 and predicted altitude Hp and the cam, which is three-dimensional, is positioned rotationally and axially in proportion to Rp and Hp, respectively, by means hereinafter described.

Disc 80 of gear 178 is constantly driven, as from 60 constant speed motor III, which may also serve. as the source of power for the constant speed discs of the x wind correction mechanism 71 (disc 182) and the y wind correction mechanism 183 (disc 184, Fig. 1B). Disc 71 is therefore driven from 65 cylinder 7711 at a rate proportional to 1 T 70 and since, when the self-adjusting variable speed gear comprising gear 14 and differential 12 reaches a state of equilibrium, the rate of rotation of cylinder 173 must be equal to or proportional to the rate of rotation of shaft 189, ball carriage 75 71 will be automatically positioned to impart such speed to cylinder 73. In this self-adjusting arrangement differential 72 serves as an equalizer of the speeds of shaft 189 and cylinder 73, since if these speeds, as fed into two arms of the differentia!, are unequal, the third arm of the differential'is caused to rotate shaft 185 and thereby through pinion. 187 and rack 186 change the radial position of ball carriage 15 until equilibrium is established. The radial displacement d of ball carriage 'l when this equalizing action is completed, will, upon analysis, be found to be greater the less the speed of disc and the greater the speed of shaft 189(R). In matlheniĀŽatical fnrn, d= =-RT This product, Thich is measured by the displacement of carriage 7?, is transmitted as the angular displacement of shaft IOS, geared to rack bar 180, connected to bal carriage 70 through pinion 8T, and is added to the displacement of slide 51, representing present position of the target, by way of shaft SE' and differential 182, to position the future x slide I' in accordance with the future or predicted position of the target through a power multiplying device hereinafter described.

The wind correction obtained from device 7 as the rate of rotation of cylinder TO is added to the rate of target displacement as an accelerating or retarding factor by the differential 29 so that it is thifs corrected rate that is fed into differential 72 by shaft 0 ~. The ball carriage 190 of the wind device ?7 is radially displaceable by handwheel 20E ii accordance with the x component of wind velccity effective in deflecting the shell. Such displacement causes cylinder 70 to be driven at a velocity proportional to the correction to target velocity necessary to compensate for the wind-induced deflection or retardation of the shell. In this manner the rate of change of target position, as represented by the rate of rotation of shaft 28, is corrected for the effect of wind velocity before being multiplied by T in the operation of computing predicted target displacement during the flight of the shell.

The prediction mechanism for the y axis may be identical with that above described. Shafts 56 and 1' are connected to the y wind correction device 183 (Fig. 1B), by way of which a wind correction is set by knob 201, and also to device I30 for obtaining the prediction correction along the y axis. The disc of device IS3 maybe rotated from the same device 78 that rotates disc 76 of device 74. The predicted change of target position is indicated by the radial position of ball carriage 131 of device 130 which is transmitted by shaft 84 to differential (32 where it is added to the present position to give future position of the target along the y axis.

As stated above, according to the present invention we prefer also to introduce a future height or altitude predicting means, so that the director is equally well adapted to predict the positions of gliding targets. We again employ the output of device 78, having a rate of rotation proportional to 1 to rotate disc 138 of variable speed device 134 and we feed into equalizing differential 135 of the altitude prediction self-adjusting variable speed gear (1) the height of the target as determined by the settings of handwheels H, H', which set in a displacement and a rate of change of displacement, respectively, and as measured by the angular positions of shafts 10', S9, 38, 09 and 89', and (2) the rotation of cylinder 130, so that in the radial position which ball carriage 17 takes up, its distance from the center of the driving disc is proportional to the quotient of rate of altitude change and i or to the product of altitude rate and T. This multiplication of the rate of change of altitude and time of flight by means of an inter-connected variable speed drive and differential occurs in the 25 manner previously describede in comnection with predicted target displacements in a horizontal plane. The position of carriage 6 7 therefore indicates total change of altitude during the time, T, of the flight of the shell, which is algebraically 30 added to present altitude through follow-up device I28 (which may be controlled by contacts functioning in a manner similar to contacts NS, V8' and 18, 8S'), and differential 101 to give shaft 162 an angular position representing future alti35 tude, We employ this future altitude to position in one dimension, say axially, the time of flight cam T and preferably also the quadrant elevation cam QE and the fuse setter cam F. Said cams are 40 rotationally positioned in accordance with future horizontal range Rp from shafts 93 and 22.

The apparatus shown diagrammatically in Fig. 4 is a modification of the arrangement of Fig. 2 for predicting change of target position during the 45 flight of the shell and may be employed for prediction along any or all of the three axes, certain elements being included to adapt the apparatus to prediction in the horizontal plane which may be dispensed with for altitude or height predic50 tion, as will be pointed out. The displacement of slide 25 (corresponding to slide 1 of Fig. 2) represents target displacement along a chosen axis and is transmitted by gearing to shaft 228 driving one arm of differential 272, a second arm of which 55 is driven by roller 273 of variable speed device 276.

In this device, the disc 271 is driven at a constant speed from motor 28 and, in accordance with the previously described operation of such self-adjusting variable speed devices, when equilibrium 60 is reached, ball carriage 217 is displaced from the center of disc 270 an amount which causes roller 271 to be driven at the same speed as shaft 223. Since, with disc 276 driven at a constant speed, the roller speed varies directly and solely 65 with the displacement of the ball carriage, this displacement represents rate of change of target position along the chosen axis.

The references to slides 251 and 251' in the above description of the prediction mechanism of 70 Fig. 4 relate more particularly to the mechanism for calculating prediction in the horizontal plane where the displacements of these slides represent components of present and future target position changes. It will readily be appreciated that, for 75 altitude prediction, where according to Fig. 1B present and future target altitude are represented by angular positions only, shafts 263 and 281' will not be geared to the aforementioned slides but that present altitude, as represented by the angular position of shaft 38, for example, may be supplied to the mechanism of Fig. 4 by any suitable mechanical connection to position shaft 263 correspondingly and that altitude prediction as computed by said mechanism and as represented by the position of cam pin 279 or the shaft rotated 1 by said pin, may be reproduced as a corresponding angular position of shaft 140' (Fig. 1B).

It will be apparent that the principal difference between the prediction means shown in Figs. 2 and 4, respectively, is that in the arrangement 1 of Fig. 2, time of flight is introduced into the prediction self-adjusting variable speed device by way of disc 76, so that the displacement of the ball carriage of said device represents the product of the two factors, rate of change of target displacement and time, while in the arrangement of Fig. 4 the disc of the variable speed device is driven at a constant speed and the displacement of the ball carriage represents target rate only, which is multiplied by time by independent cam means. As noted, either of the two arrangements may be used in obtaining change of target position along any of the three axes.

Returning to the future resolving mechanism, each of the two slides 52' and 51' of the future mechanism positions a contact, 86' or 83', cooperating with one or the other of contacts 86 and 83, as hereinbefore explained. Said contacts operate the range difference and azimuth difference motors 96 and 98 preferably through the c6nnections more fully explained in Patent No. 2,065,303.

Thereby the future resolving mechanism receives the predicted coordinates of the target's position from which the future range Rp and future azimuth angle Ap may be determined by the angular position of the two gears 4I' and 43'. The former is represented by the rotation of the shaft 33 and the latter by the rotation of the shafts 40, 40', which is indicated as future azimiuth by the coarse and fine dials Ap and Ap'. Into said dials corrections may be introduced from the handwheel 104 which rotates the field of the Ap transmitter 105 transmitting the future azimuth angle to the gun through the cable 106.

A consideration of the problem being solved by the future resolving mechanism will show that it converts the two rectangular coordinates of the future position of the target into polar coordinates, range Rp and azimuth angle Ap, or, in other words, that the mechanism solves for two unknowns simultaneously and that the entire system continuously integrates for these unknowns, the machine operating by what may be termed the flow method by which the correct future positioin is obtained very quickly although every change in each variable alters the setting for the other variables. Therefore, both motors 96 and 98 operate simultaneously and each influences the position of the other.

Since the gunners must know the quadrant elevation at which the guns must be pointed, which is the sum of the future elevation angle and the "super" elevation, and since both future elevation and superelevation are functions of future horizontal range Rp and altitude Hp, we prefer to compute the sum of the two on the same cam QE to give quadrant elevation. Future range Rp represented by the rotation of the shaft 93 may, therefore, be used. to rotationally position the cam shaft 92 of the cams QE, F asd T.

With the quadrant elevation cam properly laid out, therefore, the lift of the pin 112 thereon will represent the quadrant elevation, i. e., future elevation plus superelevation, this lift being transmitted through rack and pinion 113 to rotate the quadrant elevation transmitter 114 to send out quadrant elevation to the guns. If desired, coarse and fine quadrant elevation dials I II and 115' may be provided at the instrument. .0 Similarly, if the fuse cam F is properly laid out, the lift of the pin 118 will represent the fuse setter's data and this may be transmitted through the transmitter 119 to the gun. Similarly, fuse corrections may be introduced through the handie 120.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Having described our invention, what we claim and desire to secure by Letters Patent is: 1. In a fire control predictor, means actuated in accordance with the present position of the target, a future position means, and means for advancing said second means ahead of said first means in accordance with the advance in position of the target during the time of flight of the shell, including power actuated mechanical means for converting the movement of said first means into a positional displacement proportional to rate, means actuated directly from said displacement for multiplying said displacement by function of time, and means actuated directly thereby for positioning said second means.

2. In a fire control predictor, means actuated in accordace with the present position of the target, a future position means, and means for advancing said second means ahead of said first means in accordance with the advance in position of the target during the time of flight of the shell, including a driving member, a frictional driven intermediate member, the speed of which relative to that of the driving member varies with its position thereon, a third member driven by said intermediate member, said intermediate member being differentially positioned by said present position means and said third member, means positioned by the position of said intermediate member for actuating the future position means, and means for rotating said driving member at a speed inversely proportional to the time of flight of the shell.

3. A fire control predictor as claimed in claim 2, in which a correction for wind deflection is secured by a variable speed device having a memo0 ber positionable to effect change of output speed thereof, said change speed member being positioned in accordance with the wind velocity effect and the resultant output motion of said device added to the motion of the present position as means in differentially positioning said intermediate member.

4. In a fire control director of the rectilinear plan coordinate type having means for determining the time of flight of the shell and quadrant elevation determining means, means for feeding in constantly changing altitude as determined by a height finder, a constant speed motor, a variable speed device and differential gear interconnected for automatically determining from said altitude data rate of change of altitude, said variable speed device being driven by said constant speed motor, means for combining rate of change of altitude with time of flight to obtain altitude change during flight of the shell, and means for feeding the sum of altitude and change of altitude to said quadrant elevation determining means for positioning the same according to future altitude.

5. In a fire control director, means for continuously resolving the target's position into rectilinear components, self-adjusting variable speed devices equal in number to said components, each including differential means interconnecting movable members thereof, means for actuating each of said devices jointly in proportion to change of one of said components and time of flight of the shell for positioning a member in accordance with the product of the rate of change of said actuating component and time of flight, said product representing change of said target p'sition component during flight of the 6. In a fire controi director having individual means dlisplaceible to represent component changes of target position along each of three ceordinrate axes during light of the shell, nmeans in part controlling the displacement of said individual mieans in accordance with the rates of resolved target displacement along the respective axes, a time of flight three-dimensional cam, a cam pin actuated thereby, means for positioning said cam in one dimension in accordance with future altitude and in the other dimension in accordance with future range, the lift of the pin thereon being inversely proportional to the time of fight, means for converting said lift into a pr'oportional rate, and means for driving another member of said individual means in accordance with said rate.

7. In , fire control director, means for computing quadrant elevation including a three dimensional cam and a cary follower, said cam and follower being mounted for relative rotation and axial movement to raise or lower the follower, future range means for imparting one of said movements and future altitude means for imparting said other movement including present altitude means, time of flight means, an interconnected variable speed device and differential gear adapted to receive present altitude and time of flight and automatically compute therefrom change of altitude during the flight of the shell, and means for combining present altitude and change of altitude to obtain future altitude, said cam being laid out so that the lift at each point represents quadrant elevation for the corresponding future range and altitude. ' 8. In a fire control director, means for continuously resolving the target's position into rectilinear components fixed in azimuth; individual self adjusting variable speed gears actuated from each component movement, the adjustable elements of which position themselves from a reference point proportionally to a function of the rate of movement along each component, and means for further causing the positions of said elements to be proportional to a function of time of flight of the shell, means for combining the d$splacements of said adjustable elements as representing component changes of target position during flight of the shell with said components of the target's position to give future coordinate positions, and means for reconverting said last named positions into future target elevation and bearing.

9. In a fire control predictor, means actuated in accordance with the present position of the target, a future position means, and means for advancing said second means ahead of said first t means in accordance with the advance in position of the target during the time of flight of the shell, including a differential gear and a selfadjusting variable speed gear into which said first named means feeds, said variable speed gear having a driving element and a self-adjusting driven element, said self-adjusting feature being obtained by interconnection to said differential gear, and means for driving said driving element in inverse proportion to the time of flight of the Lg shell, whereby the radial position of said.driven element is proportional to the change of target position during the shell's flight.

10. A fire control predictor as claimed in claim 9, having a second variable speed device, means for setting a wind correction into the same, and means for algebraically adding the output thereof into said present position means, whereby the futura position is also corrected for wind deflection.

2 11. A fire control director as claimed in claim 5 in which said variable speed devices each include a member rotated in accordance with time of flight and said positioned member is a ball adjustably positionable away from the axis of rog tation of said rotated member to be driven at a variable speed thereby.

12. In a fire control director of the rectilinear plan coordinate type having means for determining the time of flight of the shell and quadrant 3g elevation determining means, means for feeding in constantly changing target altitude as determined by a height finder, a self-adjusting variable speed device including differential means interconnecting movable members thereof, said device having a member automatically positioned in accordance with a function of two variable quantities actuating said device, means for supplying a function of time of flight to said device as one of said quantities, means for supplying 4G rate of change of altitude as the other of said quantities, change of position of said member then being a measure of change of altitude during the flight of the shell, and means for positioning said quadrant elevation means in ac5g cordance with the sum of present altitude and said change of altitude, said sum representing future altitude.

13. In a fire control director future altitude tneans, comprising means for continuously setting g6 present target altitude as determined by a height finder, time of flight means, a variable speed device including a driving member actuated by said time of flight means in accordance with a function of time of flight, a positionable gg intermediate member driven thereby and a third member driven by said intermediate member at a rate governed by the position of said intermediate member, means actuated jointly by said present altitude means and said third member 6g for positioning said intermediate member to cause said third member to be driven at a rate proportional th rate of change of present target altitude, said intermediate member being thereby displaced from a reference position in proportion T0 to the product of said rate and time of flight, and means for combining the displacement of said intermediate member, as representative of change of target altitude during flight of the shell, with present target altitude to obtain future yg target altitude, 14. In a fire control director, means for predicting change of altitude during flight of the shell comprising means for displacing a first independent member in proportion to change of altitude, means for displacing a second independent member at a rate proportional to the reciprocal of time of flight, and means for causing said two displacements jointly to displace a third member in proportion to the quotient of rate of change of altitude and the reciprocal of time of flight, displacement of said last member thereby representing predicted change of altitude during flight of the shell, EARL W. CHAFEE BRUNO A. WiTI'KUHNS.