21x13.5EPN (21x135EPN.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 1.2500 -3.6040 0.0000 0.0000 0.6250 0.0000 0.2960 0.0000 0.3700 0.0000 0.1300 0.0000 0.0000 0.2665 1.1757 -0.4243 0.0398 -0.6545 0.6156 0.0208 0.2947 1.3632 0.3464 0.3805 0.1473 0.0250 -0.0411 0.5330 1.1171 2.4286 0.3117 -1.1429 0.6132 0.0764 0.2907 5.3173 0.3247 0.3729 0.1925 0.0569 -0.0153 0.7995 1.0836 4.9549 1.0139 -1.1226 0.6170 0.1577 0.2840 11.4107 0.3077 0.3578 0.2579 0.0905 0.0253 1.0660 1.0839 7.1545 2.2734 -0.3337 0.6257 0.2557 0.2746 18.7484 0.2977 0.3387 0.3370 0.1234 0.0770 1.3325 1.1207 9.0274 4.1048 1.3368 0.6384 0.3614 0.2626 26.1180 0.2943 0.3181 0.4234 0.1535 0.1358 1.5990 1.1885 10.5735 6.3810 3.8019 0.6539 0.4659 0.2480 32.4208 0.2947 0.2976 0.5101 0.1793 0.1976 1.8655 1.2754 11.7930 8.8338 6.6294 0.6713 0.5603 0.2306 37.0038 0.2941 0.2778 0.5898 0.1991 0.2574 2.1320 1.3680 12.6857 11.0940 9.2876 0.6894 0.6356 0.2106 39.6306 0.2881 0.2592 0.6551 0.2111 0.3093 2.3985 1.4543 13.2518 12.7622 11.3489 0.7072 0.6829 0.1879 40.2596 0.2732 0.2415 0.6969 0.2130 0.3461 2.6650 1.5260 13.4912 13.4871 12.4724 0.7237 0.6933 0.1625 38.8499 0.2480 0.2245 0.7056 0.2010 0.3588 2.9303 1.5824 13.5000 13.5000 12.8740 0.7371 0.6778 0.1352 36.2504 0.2139 0.2048 0.6910 0.1767 0.3529 3.1744 1.6241 13.5000 13.5000 13.0578 0.7457 0.6620 0.1209 34.0923 0.1964 0.1973 0.6773 0.1547 0.3470 3.4173 1.6565 13.5000 13.5000 13.0601 0.7510 0.6445 0.1181 32.1595 0.1956 0.2041 0.6637 0.1348 0.3407 3.6601 1.6800 13.5000 13.5000 13.0576 0.7530 0.6264 0.1157 30.4140 0.1944 0.2104 0.6501 0.1146 0.3334 3.9030 1.6953 13.5000 13.5000 13.0555 0.7520 0.6082 0.1134 28.8326 0.1923 0.2157 0.6364 0.0944 0.3256 4.1459 1.7027 13.5000 13.5000 13.0521 0.7481 0.5901 0.1113 27.3952 0.1895 0.2196 0.6227 0.0745 0.3178 4.3888 1.7027 13.5000 13.5000 13.0437 0.7415 0.5723 0.1093 26.0848 0.1861 0.2218 0.6091 0.0554 0.3103 4.6317 1.6957 13.5000 13.5000 13.0195 0.7322 0.5548 0.1074 24.8862 0.1822 0.2221 0.5955 0.0376 0.3035 4.8745 1.6822 13.5000 13.5000 12.9858 0.7204 0.5379 0.1057 23.7869 0.1778 0.2202 0.5819 0.0213 0.2978 5.1174 1.6626 13.5000 13.5000 12.9522 0.7062 0.5217 0.1040 22.7755 0.1730 0.2161 0.5683 0.0069 0.2935 5.3603 1.6374 13.5000 13.5000 12.9218 0.6899 0.5063 0.1025 21.8426 0.1678 0.2097 0.5548 -0.0055 0.2905 5.6032 1.6070 13.5000 13.5000 12.8966 0.6715 0.4917 0.1011 20.9798 0.1625 0.2011 0.5413 -0.0159 0.2889 5.8461 1.5717 13.5000 13.5000 12.8785 0.6511 0.4778 0.0998 20.1798 0.1569 0.1908 0.5278 -0.0244 0.2885 6.0889 1.5322 13.5000 13.5000 12.8615 0.6290 0.4643 0.0987 19.4363 0.1512 0.1796 0.5143 -0.0320 0.2883 6.3318 1.4888 13.5000 13.5000 12.8401 0.6053 0.4511 0.0976 18.7438 0.1454 0.1682 0.5007 -0.0390 0.2877 6.5747 1.4419 13.5000 13.5000 12.8162 0.5800 0.4380 0.0967 18.0973 0.1395 0.1566 0.4871 -0.0456 0.2867 6.8176 1.3920 13.5000 13.5000 12.7913 0.5534 0.4252 0.0959 17.4925 0.1335 0.1450 0.4735 -0.0519 0.2854 7.0604 1.3396 13.5000 13.5000 12.7652 0.5256 0.4125 0.0953 16.9257 0.1276 0.1334 0.4599 -0.0580 0.2837 7.3033 1.2851 13.5000 13.5000 12.7377 0.4967 0.3999 0.0947 16.3935 0.1217 0.1222 0.4464 -0.0640 0.2816 7.5462 1.2288 13.5000 13.5000 12.7085 0.4669 0.3875 0.0943 15.8930 0.1159 0.1112 0.4328 -0.0700 0.2791 7.7891 1.1714 13.5000 13.5000 12.6773 0.4363 0.3753 0.0940 15.4213 0.1101 0.1007 0.4192 -0.0760 0.2761 8.0320 1.1131 13.5000 13.5000 12.6437 0.4051 0.3631 0.0938 14.9763 0.1044 0.0907 0.4056 -0.0820 0.2727 8.2748 1.0545 13.5000 13.5000 12.6076 0.3733 0.3510 0.0937 14.5556 0.0989 0.0813 0.3920 -0.0883 0.2689 8.5177 0.9960 13.5000 13.5000 12.5685 0.3412 0.3390 0.0938 14.1575 0.0934 0.0724 0.3784 -0.0948 0.2646 8.7606 0.9380 13.5000 13.5000 12.5260 0.3089 0.3270 0.0940 13.7801 0.0882 0.0642 0.3648 -0.1016 0.2598 9.0035 0.8810 13.5000 13.5000 12.4796 0.2764 0.3151 0.0943 13.4220 0.0831 0.0567 0.3512 -0.1089 0.2545 9.2464 0.8254 13.5000 13.5000 12.4285 0.2441 0.3032 0.0947 13.0817 0.0782 0.0498 0.3377 -0.1165 0.2487 9.4892 0.7716 13.5000 13.5000 12.3721 0.2119 0.2913 0.0953 12.7580 0.0735 0.0436 0.3241 -0.1247 0.2424 9.7321 0.7202 13.5000 13.5000 12.3094 0.1801 0.2793 0.0959 12.4497 0.0691 0.0380 0.3105 -0.1334 0.2356 9.9651 0.6734 13.5000 13.5000 12.2426 0.1501 0.2678 0.0967 12.1674 0.0651 0.0333 0.2974 -0.1424 0.2286 10.0280 0.6612 13.5000 13.5000 12.2202 0.1420 0.2646 0.0969 12.0933 0.0641 0.0322 0.2939 -0.1450 0.2265 10.0811 0.6498 13.5000 13.5000 12.1791 0.1339 0.2617 0.0971 12.0315 0.0631 0.0311 0.2902 -0.1479 0.2242 10.1341 0.6321 13.5000 13.5000 12.1124 0.1197 0.2575 0.0973 11.9704 0.0615 0.0294 0.2847 -0.1543 0.2205 10.1871 0.6072 13.5000 13.5000 12.0163 0.0982 0.2517 0.0975 11.9098 0.0592 0.0272 0.2770 -0.1649 0.2153 10.2402 0.5737 13.4992 13.4992 11.8859 0.0681 0.2442 0.0977 11.8493 0.0561 0.0243 0.2670 -0.1802 0.2086 10.2932 0.5294 13.4707 13.4707 11.3518 0.0274 0.2344 0.0979 11.7657 0.0518 0.0207 0.2544 -0.2016 0.2003 10.3462 0.4697 13.4007 13.4007 10.6178 -0.0286 0.2217 0.0982 11.6479 0.0461 0.0163 0.2382 -0.2317 0.1901 10.3992 0.3820 13.2895 13.2895 9.7329 -0.1123 0.2035 0.0984 11.4965 0.0376 0.0108 0.2160 -0.2773 0.1766 10.4523 0.2121 13.1369 13.1369 8.6962 -0.2769 0.1698 0.0986 11.3118 0.0209 0.0033 0.1761 -0.3684 0.1540 10.5000 0.0289 12.9643 12.9917 12.9916 -0.4550 0.1345 0.0988 11.1403 0.0029 0.0000 0.1345 0.0000 0.0000 RADIUS: 10.50 PROPELLER RADIUS (IN) HUBRAD: 0.62 HUB RADIUS (IN) HUBTRA: 2.66 HUB TRANSITION (IN) BLADES: 2 NUMBER OF BLADES ----- INERTIA AND AREA DATA ----- TOTAL WEIGHT (LB) = 0.237871 TOTAL WEIGHT (Kg) = 0.107878 TOTAL VOLUME (IN**3) = 3.875222 TOTAL PROJECTED AREA (IN**2) = 24.5122 MOMENT OF INERTIA (SNAIL-IN**2) = 0.012340 MOMENT OF INERTIA (Kg-M**2) = 0.001394 STATIC MOMENT, ONE SIDE (IN-LB) = 0.434426 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 = 74.783 INNER LIMIT (NORMALIZED BY RADIUS) = 0.060 ----- NATURAL FREQUENCY DATA ----- LOWEST NATURAL BENDING FREQUENCY (IN TERMS OF RPM) = 5062.38 BASED ON MODULUS (MILLION) = 2.70 AND, MATERIAL DENSITY (S.G.) = 1.70 ----- AIRFOIL SECTIONS ----- AIRFOIL1: 2.67, E63 (Transition Start, Airfoil 1) AIRFOIL2: 5.78, APC12 (Transition End, Airfoil 2) AIRFOILS ARE SCALED BASED ON THICKNESS RATIO IN TABLE ABOVE. NOTE: APC12 airfoil is equivalent to NACA 4412