7x4 (7x4.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 0.6500 1.4365 0.0000 0.0000 0.3250 0.0000 0.3744 0.0000 0.2434 0.0000 0.1650 0.0000 0.0000 0.0800 0.6246 1.6943 0.0084 -0.2537 0.3221 0.0054 0.3597 0.9527 0.2247 0.1734 0.1671 0.0099 0.0008 0.1600 0.5984 1.9384 0.0647 -0.4895 0.3213 0.0199 0.3454 3.6813 0.2067 0.1685 0.1729 0.0228 0.0029 0.2400 0.5747 2.1689 0.2101 -0.6393 0.3222 0.0410 0.3317 7.9333 0.1906 0.1598 0.1810 0.0379 0.0074 0.3200 0.5572 2.3857 0.4764 -0.6247 0.3246 0.0664 0.3185 13.3291 0.1774 0.1471 0.1904 0.0543 0.0142 0.4000 0.5482 2.5889 0.8805 -0.3946 0.3284 0.0938 0.3057 19.3076 0.1676 0.1323 0.2004 0.0710 0.0226 0.4800 0.5482 2.7784 1.4172 0.0687 0.3331 0.1210 0.2936 25.1685 0.1609 0.1172 0.2103 0.0871 0.0319 0.5600 0.5556 2.9542 2.0493 0.7335 0.3387 0.1456 0.2819 30.2171 0.1566 0.1031 0.2192 0.1017 0.0413 0.6400 0.5668 3.1164 2.7015 1.5047 0.3447 0.1655 0.2707 33.8933 0.1535 0.0910 0.2262 0.1139 0.0500 0.7200 0.5780 3.2649 3.2617 2.2212 0.3511 0.1783 0.2601 35.7915 0.1503 0.0818 0.2300 0.1227 0.0571 0.8000 0.5858 3.3998 3.5960 2.6738 0.3575 0.1818 0.2500 35.5803 0.1464 0.0761 0.2293 0.1271 0.0615 0.8802 0.5910 3.5213 3.7324 2.8692 0.3641 0.1787 0.2403 34.0137 0.1420 0.0729 0.2251 0.1289 0.0633 0.9643 0.5964 3.6340 3.8573 3.0586 0.3717 0.1748 0.2308 32.4818 0.1376 0.0698 0.2202 0.1317 0.0644 1.0486 0.6016 3.7318 3.9660 3.2335 0.3797 0.1705 0.2218 31.0456 0.1334 0.0669 0.2148 0.1352 0.0647 1.1329 0.6066 3.8144 4.0585 3.3916 0.3880 0.1656 0.2134 29.6890 0.1294 0.0642 0.2090 0.1392 0.0642 1.2172 0.6112 3.8819 4.1347 3.5314 0.3964 0.1602 0.2055 28.3965 0.1256 0.0617 0.2026 0.1437 0.0632 1.3016 0.6154 3.9341 4.1950 3.6515 0.4048 0.1541 0.1982 27.1565 0.1220 0.0593 0.1958 0.1485 0.0614 1.3859 0.6189 3.9713 4.2395 3.7508 0.4130 0.1476 0.1915 25.9600 0.1185 0.0571 0.1885 0.1534 0.0591 1.4702 0.6218 3.9932 4.2683 3.8283 0.4208 0.1404 0.1854 24.8001 0.1153 0.0550 0.1807 0.1585 0.0561 1.5545 0.6238 4.0000 4.2816 3.8833 0.4282 0.1326 0.1798 23.6714 0.1122 0.0531 0.1724 0.1634 0.0526 1.6388 0.6248 4.0000 4.2881 3.9234 0.4348 0.1242 0.1748 22.6093 0.1093 0.0513 0.1636 0.1683 0.0485 1.7231 0.6248 4.0000 4.2947 3.9550 0.4406 0.1153 0.1704 21.6374 0.1065 0.0496 0.1543 0.1729 0.0435 1.8074 0.6235 4.0000 4.3016 3.9783 0.4454 0.1059 0.1666 20.7459 0.1039 0.0480 0.1446 0.1773 0.0378 1.8917 0.6209 4.0000 4.3089 3.9932 0.4490 0.0960 0.1633 19.9263 0.1014 0.0465 0.1343 0.1811 0.0314 1.9760 0.6169 4.0000 4.3167 3.9997 0.4513 0.0855 0.1606 19.1716 0.0991 0.0451 0.1236 0.1844 0.0243 2.0603 0.6113 4.0000 4.3249 4.0000 0.4521 0.0745 0.1584 18.4738 0.0968 0.0436 0.1123 0.1870 0.0167 2.1447 0.6039 4.0000 4.3326 4.0001 0.4513 0.0632 0.1561 17.8239 0.0943 0.0420 0.1006 0.1888 0.0085 2.2290 0.5947 4.0000 4.3397 4.0001 0.4486 0.0516 0.1539 17.2165 0.0915 0.0401 0.0884 0.1896 0.0000 2.3133 0.5836 4.0000 4.3461 4.0001 0.4439 0.0396 0.1516 16.6473 0.0885 0.0381 0.0757 0.1893 -0.0089 2.3976 0.5704 4.0000 4.3517 4.0001 0.4371 0.0274 0.1494 16.1123 0.0852 0.0359 0.0625 0.1878 -0.0182 2.4819 0.5549 4.0000 4.3564 4.0001 0.4280 0.0148 0.1471 15.6082 0.0816 0.0335 0.0488 0.1851 -0.0279 2.5662 0.5371 4.0000 4.3602 4.0001 0.4164 0.0019 0.1449 15.1317 0.0778 0.0309 0.0347 0.1808 -0.0379 2.6505 0.5168 4.0000 4.3628 4.0001 0.4021 -0.0113 0.1426 14.6800 0.0737 0.0282 0.0200 0.1751 -0.0483 2.7348 0.4940 4.0000 4.3641 4.0001 0.3851 -0.0249 0.1404 14.2503 0.0693 0.0254 0.0049 0.1677 -0.0590 2.8191 0.4684 3.9949 4.3609 3.9877 0.3651 -0.0387 0.1381 13.8308 0.0647 0.0225 -0.0108 0.1586 -0.0701 2.9034 0.4400 3.9749 4.3514 3.9431 0.3420 -0.0526 0.1359 13.4159 0.0598 0.0195 -0.0270 0.1476 -0.0815 2.9878 0.4087 3.9397 4.3433 3.8739 0.3156 -0.0666 0.1336 13.0268 0.0546 0.0166 -0.0436 0.1346 -0.0932 3.0721 0.3744 3.8893 4.3436 3.7885 0.2857 -0.0806 0.1314 12.6821 0.0492 0.0137 -0.0604 0.1195 -0.1051 3.1564 0.3369 3.8238 4.3588 3.6954 0.2522 -0.0946 0.1291 12.3955 0.0435 0.0109 -0.0775 0.1022 -0.1171 3.2407 0.2961 3.7431 4.3955 3.6019 0.2150 -0.1088 0.1269 12.1815 0.0376 0.0083 -0.0948 0.0826 -0.1293 3.3215 0.2536 3.6515 4.4471 3.5215 0.1756 -0.1228 0.1247 12.0291 0.0316 0.0060 -0.1119 0.0616 -0.1413 3.3427 0.2419 3.6252 4.4627 3.5026 0.1647 -0.1266 0.1242 11.9960 0.0300 0.0055 -0.1164 0.0557 -0.1445 3.3604 0.2320 3.6025 4.4761 3.4877 0.1553 -0.1298 0.1237 11.9696 0.0287 0.0050 -0.1202 0.0507 -0.1471 3.3780 0.2219 3.5792 4.4896 3.4736 0.1458 -0.1330 0.1232 11.9434 0.0273 0.0046 -0.1241 0.0456 -0.1498 3.3957 0.2111 3.5551 4.5028 3.4604 0.1356 -0.1364 0.1227 11.9171 0.0259 0.0041 -0.1281 0.0401 -0.1526 3.4134 0.1977 3.5304 4.5157 3.4487 0.1228 -0.1403 0.1223 11.8901 0.0242 0.0036 -0.1327 0.0331 -0.1557 3.4311 0.1806 3.5051 4.5275 3.4602 0.1064 -0.1451 0.1218 11.8607 0.0220 0.0030 -0.1383 0.0242 -0.1593 3.4487 0.1582 3.4791 4.5377 3.5020 0.0848 -0.1509 0.1213 11.8272 0.0192 0.0023 -0.1451 0.0124 -0.1636 3.4664 0.1262 3.4524 4.5450 3.6300 0.0537 -0.1587 0.1209 11.7872 0.0152 0.0015 -0.1542 -0.0045 -0.1690 3.4841 0.0682 3.4250 4.5492 4.3053 -0.0027 -0.1718 0.1204 11.7396 0.0082 0.0004 -0.1694 -0.0352 -0.1776 3.5000 0.0073 3.3998 3.3998 3.3998 -0.0621 -0.1855 0.1200 8.7884 0.0009 0.0000 -0.1855 0.0000 0.0000 RADIUS: 3.50 PROPELLER RADIUS (IN) HUBRAD: 0.32 HUB RADIUS (IN) HUBTRA: 0.80 HUB TRANSITION (IN) BLADES: 2 NUMBER OF BLADES ----- INERTIA AND AREA DATA ----- TOTAL WEIGHT (LB) = 0.025675 TOTAL WEIGHT (Kg) = 0.011644 TOTAL VOLUME (IN**3) = 0.418279 TOTAL PROJECTED AREA (IN**2) = 3.4692 MOMENT OF INERTIA (SNAIL-IN**2) = 0.000122 MOMENT OF INERTIA (Kg-M**2) = 0.000014 STATIC MOMENT, ONE SIDE (IN-LB) = 0.013491 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 = 92.969 INNER LIMIT (NORMALIZED BY RADIUS) = 0.093 ----- NATURAL FREQUENCY DATA ----- LOWEST NATURAL BENDING FREQUENCY (IN TERMS OF RPM) = 34687.73 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.