7.4x7.7C (74x77C.dat) v2025-1001 Simulation Date: 02/24/2026 ----- AIRFOIL SUMMARY DATA ----- DEFINITIONS: THE QUOTED PITCH REFLECTS, IN GENERAL, ANGULAR MEASURE AS DEFINED WITH A FLAT BOTTOM SURFACE. THIS WILL AGREE WITH A PRATHER GAGE MEASUREMENT OVER MOST OF THE EFFECTIVE PORTION OF THE BLADE. (NOTE: QUOTED=INPUT) THE LE-TE MEASURE IS DEFINED IN TERMS OF LEADING EDGE AND TRAILING EDGE (MOLD) PARTING LINE DATUMS. THE PRATHER MEASURE REFLECTS THE MOST LIKELY PITCH INTERPRETATION FROM A PITCH MEASUREMENT DEVICE THAT RESTS AGAINST THE LOWER SURFACE. SWEEP & RAKE ARE DEFINED WITH (MOLD) LE PARTING LINE. ZHIGH IS HIGHEST ELEVATION ON TOP SURFACE. TWIST IS DEFINED WITH (MOLD) LE AND TE PARTING LINE DATUMS. CHORD IS THE LENGTH BETWEEN (MOLD) LE AND TE PARTING LINES. CGY IS MASS OFFSET, FORE-AFT. CGZ IS MASS OFFSET, ELEVATION. STATION CHORD PITCH PITCH PITCH SWEEP(Y) RAKE(Z) THICKNESS TWIST MAX-THICK CROSS-SECTION ZHIGH CGY CGZ (IN) (IN) (QUOTED) (LE-TE) (PRATHER) (IN) (IN) RATIO (DEG) (IN) (IN**2) (IN) (IN) (IN) 0.0000 0.9000 2.2306 0.0000 0.0000 0.4500 0.0000 0.3150 0.0000 0.2835 0.0000 0.1000 0.0000 0.0000 0.1100 0.8595 3.1563 0.0122 -0.5564 0.4408 0.0046 0.3035 1.0100 0.2609 0.3305 0.1028 0.0068 -0.1162 0.2200 0.8085 3.9611 0.0960 -1.0936 0.4254 0.0171 0.2926 3.9709 0.2365 0.3149 0.1103 0.0181 -0.1143 0.3300 0.7547 4.6530 0.3209 -1.5143 0.4058 0.0351 0.2822 8.7989 0.2130 0.2907 0.1204 0.0293 -0.1105 0.4400 0.7067 5.2403 0.7570 -1.6906 0.3838 0.0564 0.2724 15.3139 0.1925 0.2586 0.1319 0.0401 -0.1048 0.5500 0.6717 5.7312 1.4695 -1.4951 0.3612 0.0789 0.2631 23.0361 0.1767 0.2232 0.1441 0.0501 -0.0976 0.6600 0.6534 6.1337 2.4994 -0.8112 0.3398 0.1005 0.2542 31.0776 0.1661 0.1883 0.1560 0.0587 -0.0894 0.7700 0.6504 6.4561 3.8229 0.4185 0.3212 0.1192 0.2457 38.3148 0.1598 0.1567 0.1664 0.0656 -0.0805 0.8800 0.6566 6.7066 5.2904 2.1034 0.3072 0.1329 0.2376 43.7355 0.1560 0.1302 0.1736 0.0703 -0.0716 0.9900 0.6641 6.8933 6.5809 3.9082 0.2996 0.1395 0.2298 46.6135 0.1526 0.1098 0.1758 0.0725 -0.0632 1.1000 0.6666 7.0245 7.2535 5.2557 0.3000 0.1369 0.2223 46.3830 0.1482 0.0951 0.1710 0.0719 -0.0559 1.2084 0.6649 7.1073 7.3586 5.9576 0.3057 0.1280 0.2151 44.1033 0.1430 0.0847 0.1614 0.0694 -0.0508 1.2895 0.6636 7.1439 7.4066 6.3526 0.3096 0.1213 0.2099 42.4324 0.1393 0.0783 0.1543 0.0679 -0.0483 1.3690 0.6623 7.1621 7.4348 6.6447 0.3131 0.1147 0.2049 40.8391 0.1357 0.0731 0.1473 0.0666 -0.0468 1.4484 0.6609 7.1660 7.4477 6.8532 0.3163 0.1081 0.2000 39.2951 0.1322 0.0688 0.1403 0.0656 -0.0461 1.5279 0.6596 7.1587 7.4483 6.9902 0.3191 0.1015 0.1952 37.8060 0.1287 0.0653 0.1334 0.0649 -0.0459 1.6074 0.6583 7.1433 7.4400 7.0687 0.3216 0.0949 0.1904 36.3774 0.1253 0.0624 0.1264 0.0643 -0.0463 1.6869 0.6570 7.1228 7.4258 7.1019 0.3238 0.0883 0.1856 35.0152 0.1219 0.0600 0.1195 0.0640 -0.0472 1.7664 0.6557 7.1003 7.4088 7.1016 0.3257 0.0818 0.1809 33.7252 0.1186 0.0580 0.1126 0.0637 -0.0486 1.8459 0.6544 7.0790 7.3923 7.0823 0.3272 0.0754 0.1762 32.5126 0.1153 0.0562 0.1056 0.0635 -0.0503 1.9253 0.6532 7.0618 7.3792 7.0634 0.3284 0.0690 0.1715 31.3827 0.1120 0.0545 0.0987 0.0632 -0.0523 2.0048 0.6520 7.0520 7.3728 7.0524 0.3293 0.0628 0.1667 30.3401 0.1087 0.0527 0.0918 0.0629 -0.0546 2.0843 0.6509 7.0525 7.3760 7.0530 0.3298 0.0566 0.1620 29.3890 0.1054 0.0510 0.0849 0.0624 -0.0572 2.1638 0.6498 7.0665 7.3919 7.0669 0.3300 0.0505 0.1572 28.5329 0.1021 0.0494 0.0780 0.0618 -0.0601 2.2433 0.6488 7.0970 7.4236 7.0974 0.3299 0.0446 0.1523 27.7751 0.0988 0.0477 0.0711 0.0610 -0.0634 2.3228 0.6478 7.1471 7.4741 7.1475 0.3295 0.0387 0.1473 27.1180 0.0955 0.0460 0.0642 0.0601 -0.0670 2.4022 0.6467 7.2137 7.5401 7.2140 0.3287 0.0330 0.1423 26.5446 0.0921 0.0443 0.0573 0.0591 -0.0709 2.4817 0.6446 7.2664 7.5914 7.2667 0.3276 0.0272 0.1374 25.9587 0.0886 0.0425 0.0504 0.0581 -0.0745 2.5612 0.6413 7.3036 7.6260 7.3039 0.3262 0.0215 0.1325 25.3555 0.0850 0.0406 0.0436 0.0573 -0.0779 2.6407 0.6368 7.3282 7.6471 7.3285 0.3244 0.0158 0.1276 24.7445 0.0813 0.0386 0.0367 0.0567 -0.0811 2.7202 0.6311 7.3434 7.6577 7.3436 0.3223 0.0100 0.1228 24.1346 0.0775 0.0365 0.0298 0.0562 -0.0841 2.7997 0.6242 7.3523 7.6610 7.3525 0.3199 0.0043 0.1180 23.5337 0.0737 0.0343 0.0229 0.0559 -0.0870 2.8791 0.6162 7.3578 7.6599 7.3580 0.3172 -0.0013 0.1132 22.9492 0.0697 0.0321 0.0160 0.0559 -0.0898 2.9586 0.6069 7.3632 7.6575 7.3634 0.3141 -0.0070 0.1084 22.3881 0.0658 0.0298 0.0092 0.0560 -0.0926 3.0381 0.5965 7.3715 7.6569 7.3716 0.3107 -0.0126 0.1035 21.8566 0.0617 0.0275 0.0023 0.0564 -0.0953 3.1176 0.5849 7.3858 7.6611 7.3859 0.3070 -0.0182 0.0986 21.3607 0.0577 0.0253 -0.0046 0.0569 -0.0981 3.1971 0.5721 7.4092 7.6731 7.4093 0.3029 -0.0238 0.0937 20.9057 0.0536 0.0230 -0.0115 0.0577 -0.1010 3.2766 0.5579 7.4447 7.6958 7.4448 0.2983 -0.0295 0.0886 20.4966 0.0495 0.0207 -0.0185 0.0586 -0.1040 3.3560 0.5327 7.4955 7.7340 7.4972 0.2842 -0.0387 0.0835 20.1416 0.0445 0.0178 -0.0291 0.0548 -0.1093 3.4355 0.4903 7.5646 7.7901 7.5753 0.2546 -0.0532 0.0783 19.8440 0.0384 0.0142 -0.0453 0.0428 -0.1181 3.5118 0.4297 7.6511 7.8627 7.6825 0.2082 -0.0733 0.0732 19.6128 0.0315 0.0102 -0.0671 0.0218 -0.1304 3.5337 0.4078 7.6798 7.8871 7.7202 0.1907 -0.0805 0.0717 19.5566 0.0293 0.0091 -0.0749 0.0135 -0.1348 3.5524 0.3871 7.7060 7.9093 7.7556 0.1739 -0.0873 0.0705 19.5121 0.0273 0.0080 -0.0821 0.0054 -0.1389 3.5711 0.3642 7.7335 7.9327 7.7945 0.1551 -0.0948 0.0692 19.4708 0.0252 0.0070 -0.0901 -0.0037 -0.1435 3.5897 0.3387 7.7625 7.9574 7.8381 0.1339 -0.1031 0.0679 19.4327 0.0230 0.0059 -0.0989 -0.0142 -0.1486 3.6084 0.3100 7.7931 7.9832 7.8876 0.1097 -0.1125 0.0666 19.3978 0.0206 0.0049 -0.1087 -0.0262 -0.1543 3.6271 0.2772 7.8252 8.0104 7.9464 0.0817 -0.1231 0.0653 19.3660 0.0181 0.0039 -0.1199 -0.0403 -0.1608 3.6458 0.2386 7.8589 8.0387 8.0211 0.0482 -0.1357 0.0639 19.3372 0.0153 0.0028 -0.1330 -0.0574 -0.1684 3.6645 0.1908 7.8942 8.0682 8.1309 0.0061 -0.1513 0.0626 19.3113 0.0119 0.0018 -0.1493 -0.0792 -0.1778 3.6832 0.1231 7.9312 8.0986 8.3739 -0.0547 -0.1734 0.0613 19.2876 0.0075 0.0007 -0.1722 -0.1111 -0.1911 3.7000 0.0231 7.9660 7.9660 7.9660 -0.1462 -0.2062 0.0601 18.9143 0.0014 0.0000 -0.2063 0.0000 0.0000 RADIUS: 3.70 PROPELLER RADIUS (IN) HUBRAD: 0.45 HUB RADIUS (IN) HUBTRA: 1.10 HUB TRANSITION (IN) BLADES: 2 NUMBER OF BLADES ----- INERTIA AND AREA DATA ----- TOTAL WEIGHT (LB) = 0.043762 TOTAL WEIGHT (Kg) = 0.019847 TOTAL VOLUME (IN**3) = 0.712933 TOTAL PROJECTED AREA (IN**2) = 4.1037 MOMENT OF INERTIA (SNAIL-IN**2) = 0.000186 MOMENT OF INERTIA (Kg-M**2) = 0.000021 STATIC MOMENT, ONE SIDE (IN-LB) = 0.020674 SANITY CHECK DATA ARE BELOW DENSITY (SPECIFIC GRAVITY, INPUT FILE) = 1.700 DENSITY (INPUT FILE, LB/IN**3) = 0.6138E-01 AVERAGE DENSITY (FROM WT & VOL ABOVE, LB/IN**3) = 0.6138E-01 ACTIVITY FACTOR = 122.204 INNER LIMIT (NORMALIZED BY RADIUS) = 0.122 ----- NATURAL FREQUENCY DATA ----- LOWEST NATURAL BENDING FREQUENCY (IN TERMS OF RPM) = 41050.40 BASED ON MODULUS (MILLION) = 3.50 AND, MATERIAL DENSITY (S.G.) = 1.70 ----- AIRFOIL SECTIONS ----- AIRFOIL1: 2.00, CLARK-Y (Transition Start, Airfoil 1) AIRFOIL2: 3.00, CLARK-Y (Transition End, Airfoil 2) AIRFOILS ARE SCALED BASED ON THICKNESS RATIO IN TABLE ABOVE.