7.8x4 (78x4.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 2.3664 0.0000 0.0000 0.4500 0.0000 0.3889 0.0000 0.3500 0.0000 0.1100 0.0000 0.0000 0.1060 0.8647 2.5035 -0.0093 -0.3697 0.4447 0.0033 0.3872 -0.7965 0.3348 0.2555 0.1123 0.0097 -0.0581 0.2120 0.8248 2.6334 0.0294 -0.7172 0.4397 0.0121 0.3823 1.2635 0.3153 0.2485 0.1185 0.0253 -0.0571 0.3180 0.7843 2.7562 0.1583 -0.9640 0.4352 0.0249 0.3740 4.5291 0.2933 0.2351 0.1271 0.0438 -0.0545 0.4240 0.7474 2.8719 0.4122 -1.0196 0.4315 0.0403 0.3623 8.7950 0.2708 0.2149 0.1371 0.0642 -0.0501 0.5300 0.7175 2.9805 0.8131 -0.8188 0.4289 0.0569 0.3474 13.7220 0.2493 0.1912 0.1477 0.0852 -0.0442 0.6360 0.6967 3.0820 1.3612 -0.3304 0.4274 0.0733 0.3292 18.8106 0.2293 0.1667 0.1577 0.1059 -0.0368 0.7420 0.6846 3.1763 2.0216 0.4199 0.4275 0.0882 0.3076 23.4428 0.2106 0.1436 0.1663 0.1251 -0.0283 0.8480 0.6793 3.2636 2.7122 1.3232 0.4293 0.1000 0.2848 26.9779 0.1935 0.1234 0.1722 0.1419 -0.0194 0.9540 0.6778 3.3437 3.2995 2.1730 0.4331 0.1075 0.2641 28.8305 0.1790 0.1073 0.1742 0.1551 -0.0109 1.0600 0.6778 3.4167 3.6138 2.6809 0.4392 0.1093 0.2457 28.4841 0.1665 0.0959 0.1711 0.1632 -0.0044 1.1652 0.6791 3.4822 3.6864 2.8432 0.4468 0.1068 0.2296 26.7266 0.1559 0.0883 0.1646 0.1677 -0.0005 1.2568 0.6812 3.5334 3.7410 2.9734 0.4540 0.1042 0.2174 25.3481 0.1481 0.0828 0.1590 0.1719 0.0019 1.3477 0.6839 3.5790 3.7894 3.0942 0.4613 0.1012 0.2069 24.1094 0.1415 0.0782 0.1535 0.1762 0.0034 1.4385 0.6872 3.6194 3.8328 3.2062 0.4688 0.0976 0.1980 22.9803 0.1361 0.0744 0.1481 0.1805 0.0041 1.5293 0.6908 3.6545 3.8719 3.3087 0.4761 0.0936 0.1908 21.9468 0.1318 0.0714 0.1428 0.1847 0.0040 1.6201 0.6944 3.6845 3.9071 3.4012 0.4832 0.0889 0.1853 20.9975 0.1286 0.0690 0.1374 0.1888 0.0033 1.7110 0.6979 3.7092 3.9390 3.4833 0.4900 0.0837 0.1813 20.1230 0.1266 0.0673 0.1321 0.1927 0.0019 1.8018 0.7011 3.7286 3.9676 3.5544 0.4961 0.0779 0.1788 19.3138 0.1254 0.0661 0.1267 0.1962 0.0000 1.8926 0.7037 3.7429 3.9909 3.6140 0.5015 0.0721 0.1765 18.5521 0.1242 0.0650 0.1213 0.1995 -0.0022 1.9834 0.7056 3.7520 4.0086 3.6621 0.5060 0.0663 0.1741 17.8308 0.1229 0.0640 0.1158 0.2022 -0.0045 2.0743 0.7064 3.7570 4.0215 3.6992 0.5095 0.0606 0.1718 17.1483 0.1214 0.0629 0.1102 0.2044 -0.0070 2.1651 0.7060 3.7580 4.0299 3.7254 0.5118 0.0549 0.1695 16.5009 0.1197 0.0618 0.1045 0.2055 -0.0096 2.2559 0.7042 3.7552 4.0335 3.7407 0.5126 0.0492 0.1672 15.8844 0.1177 0.0607 0.0987 0.2058 -0.0124 2.3468 0.7007 3.7484 4.0324 3.7448 0.5119 0.0435 0.1648 15.2949 0.1155 0.0594 0.0927 0.2050 -0.0152 2.4376 0.6953 3.7378 4.0264 3.7378 0.5095 0.0378 0.1625 14.7292 0.1130 0.0580 0.0866 0.2034 -0.0181 2.5284 0.6879 3.7233 4.0153 3.7233 0.5053 0.0321 0.1602 14.1845 0.1102 0.0564 0.0802 0.2008 -0.0210 2.6192 0.6780 3.7049 3.9991 3.7049 0.4990 0.0264 0.1578 13.6581 0.1070 0.0543 0.0736 0.1973 -0.0239 2.7101 0.6657 3.6825 3.9772 3.6826 0.4904 0.0207 0.1555 13.1470 0.1035 0.0519 0.0668 0.1930 -0.0267 2.8009 0.6506 3.6563 3.9494 3.6565 0.4796 0.0149 0.1532 12.6487 0.0997 0.0491 0.0598 0.1876 -0.0296 2.8917 0.6324 3.6262 3.9157 3.6264 0.4662 0.0091 0.1509 12.1619 0.0954 0.0458 0.0524 0.1813 -0.0324 2.9826 0.6111 3.5922 3.8758 3.5924 0.4501 0.0032 0.1485 11.6851 0.0908 0.0423 0.0448 0.1739 -0.0353 3.0734 0.5863 3.5543 3.8292 3.5545 0.4311 -0.0028 0.1462 11.2159 0.0857 0.0384 0.0368 0.1653 -0.0383 3.1642 0.5579 3.5125 3.7749 3.5127 0.4091 -0.0090 0.1439 10.7508 0.0803 0.0343 0.0285 0.1554 -0.0414 3.2550 0.5256 3.4668 3.7118 3.4669 0.3840 -0.0152 0.1415 10.2865 0.0744 0.0301 0.0198 0.1439 -0.0446 3.3459 0.4892 3.4171 3.6383 3.4173 0.3555 -0.0216 0.1392 9.8187 0.0681 0.0258 0.0108 0.1310 -0.0479 3.4367 0.4484 3.3638 3.5521 3.3639 0.3234 -0.0281 0.1369 9.3415 0.0614 0.0215 0.0013 0.1164 -0.0513 3.5275 0.4032 3.3109 3.4538 3.3111 0.2877 -0.0348 0.1346 8.8572 0.0542 0.0172 -0.0086 0.1002 -0.0549 3.6183 0.3531 3.2609 3.3456 3.2610 0.2482 -0.0417 0.1322 8.3715 0.0467 0.0131 -0.0189 0.0824 -0.0586 3.7092 0.2981 3.2137 3.2213 3.2137 0.2047 -0.0487 0.1299 7.8697 0.0387 0.0093 -0.0297 0.0632 -0.0626 3.7963 0.2404 3.1710 3.0710 3.1710 0.1590 -0.0557 0.1277 7.3364 0.0307 0.0061 -0.0406 0.0432 -0.0666 3.8202 0.2237 3.1598 3.0203 3.1597 0.1458 -0.0576 0.1271 7.1719 0.0284 0.0053 -0.0436 0.0375 -0.0677 3.8404 0.2093 3.1504 2.9726 3.1503 0.1344 -0.0593 0.1265 7.0230 0.0265 0.0046 -0.0462 0.0326 -0.0687 3.8606 0.1947 3.1412 2.9192 3.1411 0.1228 -0.0610 0.1260 6.8622 0.0245 0.0040 -0.0489 0.0276 -0.0696 3.8808 0.1797 3.1321 2.8585 3.1320 0.1109 -0.0626 0.1255 6.6862 0.0226 0.0034 -0.0515 0.0225 -0.0706 3.9010 0.1645 3.1232 2.7882 3.1230 0.0989 -0.0643 0.1250 6.4898 0.0206 0.0029 -0.0542 0.0174 -0.0716 3.9212 0.1490 3.1144 2.7053 3.1142 0.0866 -0.0661 0.1245 6.2661 0.0185 0.0024 -0.0569 0.0121 -0.0726 3.9414 0.1326 3.1057 2.6047 3.1064 0.0734 -0.0679 0.1239 6.0041 0.0164 0.0019 -0.0598 0.0065 -0.0737 3.9616 0.1099 3.0972 2.4782 3.1801 0.0542 -0.0704 0.1234 5.6855 0.0136 0.0013 -0.0638 -0.0022 -0.0752 3.9818 0.0724 3.0888 2.3136 3.6525 0.0202 -0.0746 0.1229 5.2833 0.0089 0.0006 -0.0703 -0.0182 -0.0779 4.0000 0.0043 3.0814 3.0814 3.0813 -0.0446 -0.0818 0.1224 6.9898 0.0005 0.0000 -0.0818 0.0000 0.0000 RADIUS: 4.00 PROPELLER RADIUS (IN) HUBRAD: 0.45 HUB RADIUS (IN) HUBTRA: 1.06 HUB TRANSITION (IN) BLADES: 2 NUMBER OF BLADES ----- INERTIA AND AREA DATA ----- TOTAL WEIGHT (LB) = 0.041851 TOTAL WEIGHT (Kg) = 0.018980 TOTAL VOLUME (IN**3) = 0.681802 TOTAL PROJECTED AREA (IN**2) = 4.7602 MOMENT OF INERTIA (SNAIL-IN**2) = 0.000245 MOMENT OF INERTIA (Kg-M**2) = 0.000028 STATIC MOMENT, ONE SIDE (IN-LB) = 0.024073 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 = 89.350 INNER LIMIT (NORMALIZED BY RADIUS) = 0.112 ----- NATURAL FREQUENCY DATA ----- LOWEST NATURAL BENDING FREQUENCY (IN TERMS OF RPM) = 30238.67 BASED ON MODULUS (MILLION) = 2.80 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.