014449-1 -T SURFACE FIELD MEASUREMENTS ON SCALE MODEL F-111 AIRCRAFT By Valdis V. Liepa The Radiation Laboratory Department of Electrical and Computer Engineering The University of Michigan Ann Arbor, Michigan 48109 September 1977

014449-1 -T ABSTRACT Data have been obtained for the current and charge induced on a scale model F-l1 aircraft when illuminated by a plane electromagnetic wave in a simulated free space environment. The measurements were made on 1/135 and 1/72 scale models over the frequency range 450 - 4000 MHz, simulating 3.3 - 55.7 MHz full scale. The test points and the types of excitations were chosen to correspond to those used in the full scale measurements in the ARES facility at Kirtland Air Force Base.

014449-1 -T PREFACE It is a pleasure to acknowledge the assistance of Messrs. K. Powers, R. Stoddard, J. Tedesco, and K. Young in performing the measurements, computer programming, data processing, model preparation, and other tasks needed to obtain these data. Special thanks go to Mr. I. LaHaie who spent many frustrating hours in the process of interfacing the HP9830A calculator with the University of Michigan computer. The help provided by the Computing Center personnel, especially Mr. Dave Flower, is also acknowl edged.

014449-1 -T TABLE OF CONTENTS Section Page Abstract............. i Preface................. ii I INTRODUCTION............... 1 II MEASUREMENTS.............. 2 III DATA. v.......... 8 iii

01 4449-1 -T TABLE OF ILLUSTRATIONS Figure No. Page 1. 1/135 and 1/72 scale models of the F-lil aircraft.................. 4 2. Charge sensor mounted on the wing of the 1/72 scale model at TP:364........... 5 3. Measurement of the current on top of the fuselage at TP:364, shown as oriented in the chamber: top incidence, E-parallel to fuselage...... 7 4. Measurement points on F-lll. The measurements were made at encircled stations only...... 9 5. Directions of measured surface current components 11 6-32. Data plots................... 15-41 iv

014449-1 -T SECTION I INTRODUCTION The data presented here were obtained for the Mission Research Corporation (MRC) to assist in extrapolating [1] the results of full scale tests made in an EMP simulator, and the test points and excitation conditions were chosen to correspond to those used in measurements made in the ARES facility at Kirtland Air Force Base. The data were recorded, reduced and plotted digitally, and have also been furnished to MRC in digital form on computer cards, as well as stored on (IBM compatible) magnetic tape. So as not to lose information that may be relevant to the development of analytical techniques such as SEM, no smoothing has been carried out to remove the minor perturbations attributable to measurement noise, nor have any corrections been applied to account for probe integration. Based on previous measurements performed using clean cylindrical and spherical bodies, probe correction factors have been developed [2] which could be applied to the data in digital form were it found desirable to do so. 1. Carl E. Baum, "Extrapolation Techniques for Interpreting the Results of Tests in EMP Simulators in Terms of EMP Criteria", AFWL Sensors & Simulation Notes, Note 222, 1977. 2. Valdis V. Liepa, "Sweep Frequency Surface Field Measurements", University of Michigan Radiation Lab Report No. 013378-1-F, AFWL-TR-75-217, 1975. 1

014449-1 -T SECTION II MEASUREMENTS For the most part the measurement techniques are the same as previously used [3], but two changes that were made are the use of a new and larger anechoic chamber [4] and the direct digitization and recording of the data. The measurements were performed over the three bands 450 - 1100, 1000 - 2000 and 2000 - 4000 MHz, using 1/135 and 1/72 scale model F-111 aircraft. There were two models of each scale size, one for current (J) and one for charge (Q) measurements. Based on the actual dimensions of the F-111A, the precise scaling factors for the models are presented in Table 1. These were employed to convert a measurement frequency to a full scale one using the fuselage scale for the case of E-parallel to the fuselage and the wingspan scale for the case of E-perpendicular to the fuselage. The table also gives the measured local (surface) radii of the equivalent cylinders at the test points 181, 150 and 382. These would be needed for adjustment of the data for probe integration effects were it found desirable to incorporate such corrections. 3. Valdis V. Liepa, "Surface Field Measurements on Scale Model EC-135 Aircraft", Univ. of Michigan Radiation Lab Report No. 014182-1-F, AFWL-TR77-101, 1977. 4. Valdis V. Liepa, "Surface Field Measurements on Scale Model E-4 Aircraft"', Univ. of Michigan Radiation Lab Report No. 014182-2-F, AFWL-TR-77-111, 1977. 2

014449-1 -T Table 1 Scale Factors for the Models (Full scale dimensions used (radome removed): length = 19.63 m, wingspan = 19.20 m) Local Surface Curvature Radius At Size J/Q Fuselage Wingspan TP:181 TP:150 TP:382 1/72 3 72.03 72.82 0.95 cm 1.43 cm flat 1/72 Q 71.91 72.77 0.95 cm 1.43 cm flat 1/135 J 136.79 141.71 0.53 rm 1.27 cm flat 1/135 Q 137.15 134.4 0.53 cm 1.27 cm flat The currents were measured using loops 0.31 cm in outside diameter made from 0.76 mm diameter 50 ohm semi-rigid coax and the charges (or normal electric fields) using a 0.2 cm long monopole made by extending the center conductor of the coax. The measurement procedure was to make all the current measurements on the 1/72 and 1/135 models in one frequency band and then repeat the measurements in each of the other two bands. The process was then repeated for the charge measurements. Figure 1 is a photograph of the models. The unmodified (smooth) ones on the left were used for the current measurements and the ones on the right for the charge measurements. The patches are adhesive copper tape covering slots cut in the models to accommodate the charge sensors. Figure 2 shows a closeup of the charge sensor mounted on the wing of the 1/72 model at station TP:364. The signal lead passes through the wing and then along the bottom 3

0144494-1T'v.."'.' I:..... F igure I' 1/135 and 1/I? scale models of the 1-.111 aircraft. Those on the left were used for current measurements and those on the right, with P~atches of copper tape attached, wore used for charge measurements. 4MM~::...............'K::.i iii~:::'i- ii: ~~~~~~~~~~~~~~~~iiii:~~0 aii k A:Tii: i: l::-~~~~~~~::~~~~~~i::~~~x IIN~~~~~~~ ~~I~~::::::i-::j:::;::a:~~~~~~~~~~~~~~::~~~::::~::i~.- ines:a:... Figure 1. 1/13 and 1/72 scal modM., i 4:4,.........t Those on tke lef~~~e; Lrcre used for current mcasure........ and those on the right, \rrith patiiis x........... attached, were used for charge mcasurcmcnls.~-W............

014449-1-T:'~~~~~~~~~~~~~.:....~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mod.-el s-a: t TP'64

014449-1-T of the fuselage, leaving the model near the trailing edge of the wings. Underneath the wing and on the fuselage the coax is taped to avoid introducing new current paths that could perturb the measurements. The set-up in measuring the current at TP:150 is shown in Figure 3. For this measurement the incidence was topside with electric vector parallel to the fuselage. Note that the sensor lead is perpendicular to the incident electric vector to minimize interaction.

014449-1-T @P'-..>.... Figure 3: Measurement of the current on top of the fuselage at TP:364, shown as oriented in the chamber: top incidence, E-parallel to fuselage.

014449-1-T SECTION III DATA Results are presented for 21 current and 5 charge measurements and the cases considered are summarized in Table 2, p. 14, which can also serve as a guide in finding a particular data set. The locations of the test points are shown in Figure 4, but the corresponding station numbers will also be used to describe these points. In the identification of the station numbers the letter abbreviations are as follows: F - fuselage WL - water line LBL - left buttock line T - top of the aircraft B - bottom of the aircraft The number between the letters is the distance in inches on the full scale aircraft. For the distances measured along the fuselage (radome removed), the numbers start from 114.25 at the front and increase to 887.107 at the rearmost point which is at the top of the vertical stabilizer. For the wing stations two numbers are used, one giving the distance from the front of the aircraft and the other the distance out from the plane of symmetry.

01 4449-1 -T X2 185 387 TOP VIEW) Radome not installed /. 182 X4 961 (Side of A/C) X5 (BOTTOM VIEW) Figure 4: Measurement points on F-Ill. The measurements were made at encircled stations only. 9

014449-1-T The particular measurement situation is described in the information contained on each figure. As an example, consider Figure 7. The title at the top gives the test point location (TP:181), the polarization (PAR, i.e. electric field parallel to the fuselage), the quantity measured (Q), and the file names where the data is stored (F603,..., F528). As a further aid, a sketch is included showing the measurement point, the direction of incidence, and the polarization. The current and charge data are normalized to the incident fields Ho and Eo, respectively, measured at TP:150 (F352T) without the model present. TP:150 is iWt thus the reference origin for the phase. The e time convention is used, implying a decrease in phase on moving away from the source. Figure 5 shows the components of the skin currents measured at the various test locations. The word "axial" (JA) and "circumferential" (JC) used in describing these components are somewhat arbitrary. Thus, on the wings and horizontal and vertical stabilizers, the components JA and JC are actually perpendicular and parallel to the fuselage, respectively. At some of the stations considered, the measured field component would be zero under ideal conditions, and these cases are identified by an asterisk in Table 2 and on the corresponding figures. Since the data have been obtained under practical conditions using actual models in an anechoic chamber, small but non-zero fields are measured even for these cases. Their amplitudes are indicative of the noise or background level and could conceivably be used in an error analysis. 10

TOP J BOTTOM Figure 5: Directions of Measured Surface Current Components. 11

014449-1 -T For those who may require the data in digital form, an illustrative data set is given in Table 3 showing the data used to generate a part of Figure Six data files recorded over three frequency bands with two different scale models are needed to generate the curves in any given case. The data are stored on magnetic tape and can be provided on tape or punched cards to any authorized user. The file format is as follows: i. FILENAME (4A4) 2. Comments (18A4) 3. Comments (18A4) 4. TITLE used in plotting (18A4) 5. FMIN, FMAX, AMPMIN, AMPMAX, PHASEMIN, PHASEMAX, NN (4F8.3, 2F8.2, 15) 6. F(1) AMP(1) PHASE(1) F(2) AMP(2) PHASE(2) F(3) AMP(3) PHASE(3) (3(2F8.3, F8.2) data c.... F(NN) AMP(NN) PHASE(NN) where NN is the number of data points in the set. 12

014449-1 -T Table 3 Illustration of data set. 4 2.3 F1 11/13,15, PAR JA, 1,A, 5/2.q/77 F-111 mP:15) P P JA; F423,L3, 5 9,447,, 1 3.2q 1 1 2. 3"8 6.399 -16F. 64 4 39 138 3.2n1 2. 43.91 3.326 2.329 44.57 3. 361 2.381 4,.73 3.396 2. 1395 44.37 3. 32 2.432 45.1 3.467 2.49'5 46. 42 3. 5 2 2.9529 4 f.13?.537 2. 572 46. 63 3. 572 2.621 46. 92 3.606 7 2.677 46.1.6 4 2 2.6%6 46.67 3.677 2.727 47. 1 4 3.712 2.922 47.59 3.749 2.354 48.05 3.793 2. 9C5 4R. 39 3.818 3. 1 9 49R.13 3.53 3. 37 1 36.S5 4, 7s 46.58 3. 9 2 3 15 3 194 4 6 3.9 8 3.192 46. 2 3 993 3.298 45.64 4.C28 3. 2"' 46.25'4.,64 3.244 4 6.86 4.C 99 3. 333 46.77 4. 13 3. 368 46.87 4. 169 3.452 46.78 4. 204 3.535 46.08 4.2 39 3.938 45.39 4.274 3.589 45.12 4.309 3.657 45. 1 4.344 3.657 44.72 4. 379 3.716 44.83 4. 415 3.774 45. 15 4. 45C 3.842 44. 7 4.485 3.928 44.09 4. 52) 3. 979 43. 92 4.,555. 1 4 3.36 4. 590 4. 1C6 43.33 4. 625 4.127 42.84 4. 666C 4. 166 42.69 4.95 4.273 43.05. 731 4. 353 42. 12 4.766 4. 422 4 1.6 9 4. 0 01 4. 533 4 1. 5 4. 836 4.594 43. 17 4.871 4.622 39.17 4.39C6 4.649 39. 17 4.941 4.666 38. 29 4.976 4.714 38.52 5.011 4.772 38.56 5.046 4.875 37.73 5.C 82 4. 95 37. 86 5. 1 1 7 5.007 37. 32 5. 152 5. 113 36. 31 5.187 5.162 36.19 5.222 5.247 35.60 5.257 5.382 34.51 5.292 5. 395 3 3.63 5.327 5.444 3 2. 77 5. 362 9.532 32. 32 5. 398 5. 55 3 1. 57 5.43.3 5.619 30. 75 5. 468 5. 7C9 3343 5.5' 3 5.786 29.12 5.538 5.865 27.3 5. 573 5.9C3 27.05 5.69, 5. 9.91 25.7 59.643 5.939 25.C2 5.678 5.896 2'4. 48 5.714.962 23.84 5.749 6.085 23.62 5.784 6. 139 22.31 5.819 6. 223 2 1. C2 95.54 6.264 2 n02 5. 889 6.234 1.35 5.924 6.248 17.49 5.959 6.262 17.24 5. 994 6.276 16.39 6.C29 6. 39 15. 17 6.065 6. 351 14. 14 6. 103 6.382 12.74 6.135 6.399 11.94 6.170 6.344 13.55 6.205 6 343 9.27 6.2u4. 5324,CO0 6.275 6.2R96 7.74 6. 31) 6.279 6.88 6.345 6.214 6.24 6.3 1 6.183.,2 5. 416 6.2n3 4.77 6.451 65.171 3.95 6.486 6.197 3.03 6.521 6.195 2.72 6.556 6. 12 1.61 6.591 6.181'.61 6.626 6.169 -O. 39 6. 66 1.0,7 - 2. 8 6.696 6. - 3. 17 6. 732 5.876 -3.66 6.767 5.788 -4.15 6. 802 5.742 -4.,3 6.837 5.711 -4.31 6.872 5.733 - 5. n 6. 9C 7 5.719 - 5.18 6. 942 5.703 -6. 36 6. 977 5. 7, 3 - 7.35 7.0 1 2 5. 6 12 -3. 3 7. C 4 5. 562 -8. 62 7.CR3 5.514 -9.21 7. 118;442 -9.71 7. 153 5.422 -1J.31 7.188 9.739 -1C.91 7.223 5.322 -11.62 7. 259 5.268 -12.13 7.293 5. 18t -12. 45 7.328 5. 1~6 -12.7 7.364 9 91 -1 2 53 7,39 5.'4 -12.54 7.434 9.019 -12.99' 7. 469 5.13 -13.03 7."54. 972 -13,6Q 7.539 4.927 -14. 15 7.574 4. 17 -1 4. 1 3 7. F9 4.7 R73 -1.81 7. 44 4.819 - 1 5. 1 7.679 4.783 -15. 43 7.715 4. 747 -15.81 7.750 4.684 -16.33 7.785 4.591 -16.46 7. 82 4. 5 21 -16. n 9 7. 55 4. 452 -16.24 7. 8 4. 4 4 -15.88 7,25 4. 7 _7 - 1 59..55 7. q64 4.3 -1 - 15 2 7 4 -.9. 031 4.?? — 1 5.19 8. 66;. 31 3. 1 -1. 28 4. - 1 9.49 13

01 4449-1 -T Table 2 Summary of Measurements E II Fuselage E I Fuselage Test Station Point Number Q A C Q JA JC Q 181 F160T Fig. 6 150 F352T Fig. 7 Fig. 8 382 F337.5B 9 10 208 F520T 11 Fig. 12* Fig. 13* 14 R1 F469B 15 16* 17* 18 198 F640B 19 20 210 F825T 21 22 23 WL265 F830T 165 |LBL130 24 25 26 27 28 F550T 364 LBL180 29 Fig. 30 F550B 365 ILBL180 31 32 * null field measurements; see page 10. 14

24. 0 F-Itt tI'Ft181 PAR QF603.5530.202.523.601I52. 18.,0 o. L 0.0 0.0 10.0 20.0 30.0 14 O. 50.0 80.0 200.0. o... -, —- - F-1tI TFt18I PRR QtF603,530.60Z 529.601,52 1 0 D. - _ 0. -100.0 8 JUNE 77 L J 0.0 10.0 20.0 30.,0 UO. O 50.0 80.0 FREUUE.NCT (PIHZ Figure 6: Charge at TP:181, E-parallel to fuselage.

t2.0. _ -, __ __..I. F-ltt TPtt50 PAR JRiF423,435.45,.447.8,t 0.0 0.0 10.0 20.0 30.0 4a.0 50.0 a0.0 2000. 0 F-ltI TPFI50 PRR JRF235,4S23,4 59,. 44 7.8. a - 800.0 -. 3.0 0.0_2ooloR~~~~~~~~~~~~,3 JUE -7 UMli 0.0 10.0 20.0 30.0 U0.0 50.0 80,0 FREgUENCY ~MH H] Figure 7: Axial current atr TP:150l, E-paraFlel to fuselage. 16

F-I 1 TfP'150 PERP JCFl41 1.330,.51l,52,38,5 6.0 F= 1. 0 4.0 2,0 0.0......... 7 JUNE 77 UHM 0.... 0.0 1 0,o 20, D 3. 0.0 0. O 50. o 80 200.0, I I F-1it TPtt50 PE-RP JCFt1tt.330.511.523.38.5 s 0,0 ~-2 0 0,100.0 3i JUNE 77 UM 0O. 10.0 20.0 30.0 40.0 50.0 0.0 FREfU ENCT tHHZ Figure 8: Circumferential current at TP:150, E-perpendicular to fuselage.

F-tII TPt382 PAR JRAtF418.30,454,1442, I 4 E.. 0 2.0 0.0 3 JUNE 77 UM 0.0 10.0 20.0 30.0 40.0 50.0 60.0 200,0. F-IlI Tt382 P RR JRtFt18,O430,t54.442.1t.L 100,0 0.0 E -1000 -200. 0 i 0.0 10.0 20.0 30.0 UO.O 50.0 80.0 FRIEQUENCT IHHZI1 Figure 9: Axial current at TP:382, E-parallel to fuselage. 18

2.0. -.__ I..... —- --- F-Ill TPt382 PERP JCFU40, S.323.504, 516.31t546 0.5 7 JUNE 77 UH 1.0 0.0 10.0 20.0 30.0 U,0.0 50.0 80.0 200.0 F-ill TPtS82 PERE JCFUOU40.323S504.516.31.5 6 100.0 0.0 -100.0 -2 00. 0.-. i~............. 7 JUNE 77 UM -200....,. X... 0.0 10.0 20.0 30.0,40.0 50.0 80.0 FREQUENC tHMHZ] Figure 10: Circumferential current at TP:382, E-perpendicular to fuselage. 19

F- it TPt208 PRR JRtF422. 434. 458, 446..2,- 4.0 2.0 0 0.. 3 JUNE 77 UM 0.0 10o. 20.0 30o.0 Uo.o so.o e.0 200. 0 F-it1 TPF208 PRR JRtF422,434.4 58446.9.2 100.0. 00 -100.0 -200.0 _3 JUNE 77 Un 0.0 10.0 20.0 30.0 40.0 50.0 80.0 FREQUENCY 1MH1HZ) Figure 11: Axial current at TP:208, E-parallel to fuselage. 20

F-[II TPt208 PRR JC,Ftl6,1428.452.'440.22.18 E~ —~ *null field 3. o F 2. 0 spurious peaks 1.0 ~~~~~~~~~~o.o~~~~~7 JUNE 77 UM 0.. 0.0 10.0 20.0 30.0 lO4.0 50.0 60.0 200.0, F-III TPt208 PRR JC:Ft16.4U28,u452.1440.22.18 1 00.0 0.0 I 0 0. 0I~~~~~~~~~~~~~~~~~~~~~~~~ 7 JUNE 77 UM 0.0 ~10.0 20.0 30.0 LO.0 50.0 60. 0 F R E U ENCY t M HZ Figure 12: Circumferential current at TP:208, E-parallel to fuselage. 21

.0 F -tiI TPs208 PERt' J AF l0t.39,20,50,13, 2e,53 3 o0~~~~,5 "K*null field 20., 0I t 0.0 10.0 20.0 30.0 4OO 50.0 60.0 200.0....._ _ _ F-ll! TP%208 PERP JR F401,320.50,I513,28.5 3 115.9 K 0.0 10.0 20.0 30.0 u0.0 50,0 60.0 FREQUENCY fMH!1 Figure 13: Axial current at TP:208, E-perpendicular to fuselage. 22

~ae LasnJ oq JeLn pu Luadad-3'80Z:dl ie uaaAn3 [ LP, uajaw. nJLD:L n in6 j L114W) A:N3nOn3W A 0 09 os 0'0 O'OE 0'OZ 0 O 0' rb Li.,Nflfl, O'OOZ0'o 0 iwn LL 3Nnr c Ln s*Ls zslosrsa oih or u i oviii -oAoot 0'0 0 s09 O S o - 00on 1 0'0 0'a 0'Ol 0'0 wn LL 3gnr 6 O'Z ZS'LG';ZS'OtS'BZ_'Oth,__ JU3d _t:_gO_ _Jl 1_t11-0.

8,0 F-ltl TP.fi1 PRfi JAIF4tg9.43I,1&55.443,12.5 2. 0. _ 1:: 2,0 0.0 0.0 i. ~., 3 JUNE. 77 UH 0.0 10.0 20.0 30.0 U.0 50.0 60.0 200.0 F-tll TPiR1 PRR J~Fti9U.l&31.l&55.t412.5 0. 0 3 JUNE 77 UM 0.0 10.0 20.0 30.0 Ul0.0 50.0 60.0 FREQUENCT ritHHI Figure 15: Axial current at TP:R1, E-parallel to fuselage. 24

2. -- 0 F-111 TPtRIf PRR JCtF4X,q429,453,.441, 24.20 /7 *null field 1.0 2~~00. ~~~~~~~ 0 2i~ / ~1 J7 JUNE 77 UM F-111 TPtR1 PAR JC;FI4t7,.427,U53.441,2t4.20 -200.0 _ 7 JUNE 77 UM -200.0 0.0 10.0 20.0 30.0 L0.0 50.0 80.0 FREQUE.NCY IMHZ1 Figure 16: Circumferential current at TP:R1, E-parallel to fuselage. 25

2 0 --— t --- --- -- - d -- F-II l TP RI PEMP JAsFt403.322.503. 515, 30. 5 *null field.oL 1.0 10.0 20.0 30.0.O.0 50.0 60.0 200 0 F-I I T PRi PE if JR;FL403,322.503.35I 530.514 00.0 I - 0.0..000 -200.0 ____________________________7 JUNE 77 UmH 0.0 10.0 20.0 30.0 UOL. 50.0 60.0 FREQUENCY (HHZ) Figure 17: Axial current at TP:R1, E-perpendicular to fuselage. 26

F- tI TPF tR PERP JC,F405,324. 505. 517.32. 5 s. 0 2,0 0,0 10.0 I.0 3 JUNE 77 UM 0,0 10.0 20.0 30.0 40.0 50.0 60.0 200.0 F-1i TPtRl PERP JCtF405.324,505,517.32o4S -100.0 -200.0 0.0 10.0 20.0,0 o A 50.0 Ao.i FREOUENCT ~HMM!I Figure 18: Circumferential current at TP:R1, E-perpendicular to fuselage. 27

F-ttl TPFt18 PRR JRsF420,432,.456, 444,. 13,6 E 2,0 1.0 J0.0 X i 3 JUNE 77 UK 0.0 10.0 20.0 30.0 io.0 50.0 60.0 200.0 F-tlt TP1S98 PRR JAtF420.432.456,44L4 13.6 II 0.0 -2 00. 0. ________________, ___________ __ ^3 JUN E 7', U NM 00 10O.0 20.0 30.0 UO.O 50. 60.0 FREgUENC~ (MMHI Figure 19: Axial current at TP:198, E-parallel to fuselage. 28

4.0 F-t11 TPt98 PERP JCiFU0,6.325,506.518.3.5 8t8 3.0 D La 2.0 1.0 0.0 10.0 20.0 30.0 U0.O 50.0 60.0 200.0 F-Ill TPtt98 PERP JCiF406.325,506,518,33.58 100.0 0.0 -100.0 -200~3.10'' 3. JUNE 77 UKi,o o10.0 20.0 30.0 o. o 50o.o 0.0 -FleQUENCT IMH!1 Figure 20: Circumferential current at TP:198, E-perpendicular to fuselage. 29

2.- 0 I F-Ill TPt,210 PAR JRiF413.425.449.437,.25.16 1.0 0.5 0.0..,. 0.0 10.0 20.0 30.0 o o.o 50.0 60.0 200.0,..,, F-1ll TPt210 PRR JAtF4t13.25,149.437.25.16 100.0 100.0 [ 0. N -200.0 i 30.0 8 JUNE 77 UM 0.0 10.0 20.0 30.0 O.O 50.0 80.0 FREgUENCY (MHH1) Figure 21: Axial current at TP:210, E-parallel to fuselage. 30

4. 0 I I'_ — F-Itt TP?210 PAR JC,1F14,426,450,.438,26.15 3.0 2.0 1.0 0.0 -. 8 JUNE 77 UM 0.0 10, O 20.0 30.0 40.0 50so.o 60. 200.0 _ F-111 TPs210 PAR JCtF414,426,450,U38,26.15 100.0 0.0 -100.0 -2 0 0. 0 __ _ _ _ _ __ _ _ _ _ __ _ _ _ _ _ __ _ _ _ _ __ _ _ _ _ _8 JUNE 77 UM 0,0 10.0 20.0 30.0 U40.0 50.0 80.0 FRE3UENCY CMttll Figure 22: Circumferential current at TP:210, E-parallel to fuselage. 31

8.0 F-t1 T TP 210 PRR O F604.531.605. 532. 606. 5 4.L.'JU7 2.0 8 JUNE 77 UH 0.0. 0.0 10.0 20.0 30.0 40.0 50.0 60,0 200.0 F-Ill TPt210 PRR QsF604.53.1605.532.606,53 100,0 0.0 cc -200 0. 8 JUNE 77 UH 0,. 10.0 20.0 30.0 4O.0 50.0 80.0 FREgUENCY (HHE] Figure 23: Charge at TP:210, E-parallel to fuselage. 32

tI. 0 t -, - F- Itt TPtGS PRR JR F415, 27. S1,4U39. 23. 7 iK, 2,0 - 1.0 0.0-~~~~~~~~~~~~~~7 JUNE 77 UM, 0.0 10.0 20.0 30.0 tO.0 50.0 60.0 200,0................. F-lli TP1IGS PRR JR:F5,.42?,4t513,89.23,17 100.0 - 0.0 7: -10.0o -20.0 i...... 0.0 10.0 20.0 30.0 lO.O 50.0 60.0 FREgUENCT f1MHZ1 Figure 24: Axial current at TP:165, E-parallel to fuselage. 33

, 01 O.0;,. -,... 200.0 F-111 TFt165 PRR JCIF421. 433,, 57, 445. to.3 100.0' o.o | >;,<:' - -2 00.0 _ _JUNE J77 M 0.0 10.0 20.0 30.0 40.0 S0.0 60.0 F R E UENC~Y (MH11*1 Figure 25: Circumferential current at TP:165, E-parallel to fuselage. 34

1 2 0. I,,_-. - F-lIt TP I65 PRR QiF609.536.608,535.607'53{ 8.0 8. O 4. 0.0 _o_ _8 JUNE.7_ U 0.0 10.0 20.0 30.0 40.0 50.0 80.0 200.0 F- I TP 165 PRR OtF 09.536. 608.535. 607.53 100.0 0.0 -100.0 -200.0 a JUNE 77 UlM 0.0 10.0 20.0 30.0 O.0 so0.0 60.0 FfREQUENCY (MIHZl Figure 26: Charge at TP:165, E-parallel to fuselage. 35

2.0 F-Itl Tei 165 PERe JRiFU00,328.50a.521.56.55i 1.0 o.0 3 JUNE 77 UH 0.0 I.0 20.0 30.0 a 0.0 50.0 0. 0 200.0,, _F-111 TPIl65 PERP JRFq09,.328.50.521.36.5 1 -100.0 - 00 0 ~-2~00.~0 3 JUNE 77 U, 0.0 10.0 20.0 30.0 0.O s0.0o 80.0 FRfEUENC tfHHl! Figure 27: Axial current at TP:165, E-perpendicular to fuselage. 36

F-ll TPit65 PERP JCtF'102,.321502,514. 29,5L 3,0 S.Oi i/ 0o.0. 7 JUNE 77 UK 0.0 10.0 20.0 30.0 40.0 50.0 60.0 200.0 F-tIt TPst65 PERP JC:F402.321.502,514.29.5 4 100.0 -100.0 ~~~~-200.0, ~.......~~~.. ~~7 JUNE 77 UH I20.. 0...J 0.0 10.0 20. 0 30.0 40.0 50.0 80. 0 FREOUENCT (IH,l Figure 28: Circumferential current at TP:165, E-perpendicular to fuselage. 37

8.0 F-ttt TPrt6U PERP JAeF408.27,508.,520,=S.5 2.0 0.0.................,, S3 JUNE 77 UH 0.0 10.0 20.0 30.0 40.O 50.0 80 0 200,.0. F-111 TPt364 PERP J9RFtO8,.327.508.2.52 0,3S.S 100.0 0.0 -100.0 -200. 0.... JUNE 77 UN 0.0 10.O 20.0 30.0 40.0 50.0 80.0 FRE2UEICT {MHHI Figure 29: Axial current at TP:364, E-perpendicular to fuselage. 38

8. 0 I - - 1 F-itt TPt364 PERP Q0F610.537, 611,538,612.519 6,0 0.0 10.0 20.0 30.0 1O.O 50.0 60.0 200..0..!{r~~ F~~Ftil TPt386 PERP sF610,537.6St538,612,5 9 -00. 0 0.0 -100.0 -200.0?....... - 8 JUNE 77 UM 0.0 10.0 20.0 30.0 o. 0 50.0 60.0 FREQUENCY (MHZ) Figure 30: Charge at TP:364, E-perpendicular to fuselage. 39

8,0 F- It TPt365 PERP JRs F407.326.507.519. 34.5 9 8.0 2,0 0.0 3 JUNE.'7 UM 0.0 10.0 20.0 30.0 40.0 50.0 60.0 200.0.... F-Ill TPi365 PERP JRF1107.326,507,5139,34.S 0,0 -200.0,, 0.0 10.0 20.0 30.0'4oo0.0 50 so.0 80.0 FRFEUENCY fHH I1 Figure 31: Axial current at TP:365, E-perpendicular to fuselage. 40

6.0 F-l t TP,365 PERP QsF615,52.,614.5ql. 613,50 4.0 2.0 -20. 0,8 JUNE 77 UM. 0.0 10.0 20.0 30.0 40.0 50.0 60.0 2 00.0 F-l1l TPr365 PERP Q F61 E5ct2. 61l.541.813. g0 100. 0 0.0 -200.0.....,____________________ JUNE 77 u 0,0 10.0 20.0 30.0 40.0 50.0 60.0 FiEQUEHCT (MHZI Figure 32: Charge at TP:365, E-perpendicular to fuselage. 41

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