47:
2466:
1742:
20:
58:
2720:
2740:
2730:
2252:
167:
In reciprocating and propeller engines, disk loading can be defined as the ratio between propeller-induced velocity and freestream velocity. Lower disk loading will increase efficiency, so it is generally desirable to have larger propellers from an efficiency standpoint. Maximum efficiency is reduced
142:
helicopter is the ratio of its weight to the total main rotor disk area. It is determined by dividing the total helicopter weight by the rotor disk area, which is the area swept by the blades of a rotor. Disk area can be found by using the span of one rotor blade as the radius of a circle and then
143:
determining the area the blades encompass during a complete rotation. When a helicopter is being maneuvered, its disk loading changes. The higher the loading, the more power needed to maintain rotor speed. A low disk loading is a direct indicator of high lift thrust efficiency.
1999:
The variable diameter tiltrotor (VDTR) is a
Sikorsky concept aimed at improving tiltrotor hover and cruise performance currently limited by disk loading that is much higher in hover than conventional helicopter, and much lower in cruise than turbo-prop
904:
1328:
1222:
2162:
The A400M will be driven by four modern turboprop engines with a high disc loading.... The disc loading of the propellers is significantly higher than realised on former tactical transport aircraft like C130H or
Transall
251:
relates the mass flow to the induced velocity. The momentum theory applied to a helicopter gives the relationship between induced power loss and rotor thrust, which can be used to analyze the performance of the aircraft.
146:
Increasing the weight of a helicopter increases disk loading. For a given weight, a helicopter with shorter rotors will have higher disk loading, and will require more engine power to hover. A low disk loading improves
1116:
1023:
1624:
424:
both upstream and downstream of the disk (regardless of velocity). Since the flow far upstream of a helicopter in a level hover is at rest, the starting velocity, momentum, and energy are zero. If the homogeneous
1966:
It is interesting to note that there has always been a strong intuitive association of rotary-wing aircraft with low disc loading which is reflected in the commonly accepted name of rotor given to their lifting
1500:
1436:
788:
2204:
In the momentum theory analysis the rotor is modeled as an actuator disk, which is a circular surface of zero thickness that can support a pressure difference and thus accelerate the air through the disk.
586:
225:
The downward force on the air flowing through the rotor is accompanied by an upward force on the helicopter rotor disk. The downward force produces a downward acceleration of the air, increasing its
2256:
218:
is modeled as an infinitesimally thin disk with an infinite number of blades that induce a constant pressure jump over the disk area and along the axis of rotation. For a helicopter that is
1697:
415:
654:
512:
366:
936:
799:
704:
330:
2424:
1731:
1531:
1233:
1127:
1551:
609:
467:
447:
310:
290:
2409:
2743:
2446:
2298:
2134:
contra-rotating propellers this rotational loss can be eliminated and maximum efficiencies approaching 0.9 can be obtained even with high disc loading
1034:
944:
1559:
208:
2261:
2015:
2431:
1447:
2554:
1347:
2451:
2087:
663:
far downstream of the disk is twice the velocity at the disk, which is the same result as for an elliptically loaded wing predicted by
2023:. U.S. Government Printing Office, Washington D.C.: U.S. Federal Aviation Administration. 2000. pp. 2–4, 19–3, G-2. FAA-8083-21.
716:
2414:
2363:
2291:
2564:
523:
2657:
159:(or gyroplane) has a lower rotor disk loading than a helicopter, which provides a slower rate of descent in autorotation.
2284:
229:. This energy transfer from the rotor to the air is the induced power loss of the rotary wing, which is analogous to the
2616:
1895:
1333:
The pressure along the slipstream is always falling downstream, except for the positive pressure jump across the disk.
2465:
2436:
2229:
2197:
2155:
2127:
2065:
1951:
53:
with propeller tip vortices condensation. The C-27J uses the same engines as the MV-22, but has higher disk loading.
2680:
2601:
2559:
2072:
Reduced disk loading in the vertical mode also results in lower downwash and improved capability for autorotation.
1635:
122:
aircraft has a high disk loading relative to a helicopter in the hover mode, but a relatively low disk loading in
2270:
236:
2764:
2441:
2150:. Notes on Numerical Fluid Mechanics and Multidisciplinary Design. Vol. 3. Berlin: Springer. p. 82.
469:
developed over the disk is equal to the rate of change of momentum, which assuming zero starting velocity is:
2393:
374:
200:
1121:
So the pressure change across the disk is equal to the disk loading. Above the disk the pressure change is:
2586:
617:
100:, such as an airscrew. Airscrews with a relatively low disk loading are typically called rotors, including
2733:
2695:
2419:
2038:
NASA SP-2000-4517, "The
History of the XV-15 Tilt Rotor Research Aircraft: From Concept to Flight" (PDF)
2358:
222:, the aerodynamic force is vertical and exactly balances the helicopter weight, with no lateral force.
169:
517:
By conservation of energy, the work done by the rotor must equal the energy change in the slipstream:
475:
148:
2667:
2119:
676:
1993:
172:
can alleviate this problem allowing high maximum efficiency even at relatively high disc loading.
2368:
2145:
204:
1940:
342:
2705:
2672:
2611:
1988:
244:
2189:
899:{\displaystyle p_{2}+\ {\tfrac {1}{2}}\,\rho \,v^{2}=\,p_{0}+\ {\tfrac {1}{2}}\,\rho \,w^{2}.}
239:
relates the induced velocity downstream in the far wake field to the rotor thrust per unit of
2328:
1865:
2181:
2111:
2084:
1323:{\displaystyle p_{0}+{\tfrac {3}{2}}\,\rho \,v^{2}=\,p_{0}+\,{\tfrac {3}{4}}{\frac {T}{A}}.}
1217:{\displaystyle p_{0}-{\tfrac {1}{2}}\,\rho \,v^{2}=\,p_{0}-\,{\tfrac {1}{4}}{\frac {T}{A}}.}
679:, we assume the pressure in the slipstream far downstream is equal to the starting pressure
912:
707:
682:
315:
248:
112:
46:
8:
2373:
2353:
2343:
2112:
1708:
1508:
664:
240:
123:
2626:
2549:
2388:
2218:
2096:
1536:
594:
452:
432:
295:
275:
219:
196:
139:
2719:
2700:
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2501:
2333:
2235:
2225:
2193:
2182:
2151:
2123:
2061:
1957:
1947:
1745:
Correlation between disk loading and hover lift efficiency, for various VTOL aircraft
230:
2690:
2631:
2596:
2591:
2378:
2276:
1984:
215:
104:
73:
39:
31:
2723:
2606:
2518:
2506:
2091:
1978:
257:
2146:
Reinhard Hilbig; Wagner, Siegfried; Ulrich Rist; Hans-Joachim
Heinemann (2002).
2058:
Future
Aeronautical and Space Systems (Progress in Astronautics and Aeronautics)
2383:
1819:
1741:
337:
333:
226:
81:
247:
considers these parameters as well as the induced velocity at the rotor disk.
2758:
2647:
1961:
1703:
97:
61:
50:
2239:
2496:
2338:
2060:. AIAA (American Institute of Aeronautics & Astronautics). p. 66.
2037:
1918:
1824:
1772:
1111:{\displaystyle p_{0}+{\tfrac {1}{2}}\,\rho \,w^{2}=\,p_{0}+{\frac {T}{A}}.}
176:
69:
35:
24:
19:
1018:{\displaystyle {\frac {T}{A}}=p_{2}-\,p_{1}={\tfrac {1}{2}}\,\rho \,w^{2}}
179:
fixed-wing aircraft will have a very high disk loading on its propellers.
1887:
116:
2025:
DISC LOADING—The total helicopter weight divided by the rotor disc area.
1619:{\displaystyle P=Tv=T{\sqrt {{\frac {T}{A}}\cdot {\frac {1}{2\rho }}}}.}
57:
2533:
2528:
2476:
2313:
1871:
1849:
1827:
1803:
1799:
1778:
660:
426:
421:
264:
losses, and rotation of the slipstream in the wake are not considered.
212:
152:
108:
101:
65:
2685:
2652:
1892:
1843:
253:
127:
119:
27:
1979:
Wang, James M.; Jones, Christopher T.; Nixon, Mark W. (1999-05-27).
1495:{\displaystyle v={\sqrt {{\frac {T}{A}}\cdot {\frac {1}{2\rho }}}}.}
2662:
2523:
2491:
1794:
420:
By conservation of mass, the mass flow rate is constant across the
261:
168:
as disk loading is increased due to the rotating slipstream; using
156:
93:
1431:{\displaystyle T={\dot {m}}\,w={\dot {m}}\,(2v)=2\rho \,A\,v^{2}.}
783:{\displaystyle p_{0}=\,p_{1}+\ {\tfrac {1}{2}}\,\rho \,v^{2}.}
2148:
New
Results in Numerical and Experimental Fluid Mechanics III
2036:
Maisel, Martin D., Demo J. Giulianetti and Daniel C. Dugan.
2042:
2085:
Development of the
Autogiro : A Technical Perspective
1702:
So, the induced velocity is inversely proportional to the
581:{\displaystyle T\,v={\tfrac {1}{2}}\,{\dot {m}}\,{w^{2}}.}
1983:. 55th Annual Forum of the American Helicopter Society.
1296:
1251:
1190:
1145:
1052:
989:
867:
820:
751:
628:
538:
30:
has a relatively high disk loading, producing visible
1711:
1638:
1629:
Therefore, the induced velocity can be expressed as:
1562:
1539:
1511:
1450:
1350:
1236:
1130:
1037:
947:
915:
802:
719:
685:
620:
597:
526:
478:
455:
435:
377:
345:
318:
298:
278:
2306:
2217:
2118:. Cambridge: Cambridge University Press. pp.
2055:
1939:
1725:
1691:
1618:
1545:
1525:
1494:
1430:
1322:
1216:
1110:
1017:
930:
898:
782:
698:
648:
603:
580:
506:
461:
441:
409:
360:
324:
304:
284:
2209:
2756:
1931:
793:Between the disk and the distant wake, we have:
1937:
710:. From the starting point to the disk we have:
449:, by conservation of momentum the total thrust
2179:
1981:A Variable Diameter Short Haul Civil Tiltrotor
2292:
2224:. Cambridge, UK: Cambridge University Press.
1533:is the disk loading as before, and the power
1692:{\displaystyle v={\frac {P}{T}}=\left^{-1}.}
1946:. New York: Dover Publications. p. 3.
1028:The total pressure in the distant wake is:
2299:
2285:
1553:required in hover (in the ideal case) is:
115:typically have a higher disk loading. The
2188:. New York: Dover Publications. pp.
2175:
2173:
2171:
1992:
1414:
1410:
1388:
1369:
1294:
1280:
1266:
1262:
1188:
1174:
1160:
1156:
1081:
1067:
1063:
1004:
1000:
974:
924:
882:
878:
849:
835:
831:
766:
762:
733:
639:
562:
549:
530:
497:
400:
396:
2215:
2109:
2077:
1938:Stepniewski, W. Z.; Keys, C. N. (1984).
1740:
1227:Below the disk, the pressure change is:
670:
429:far downstream of the disk has velocity
199:of an ideal actuator disk, developed by
56:
45:
18:
2484:
410:{\displaystyle {\dot {m}}=\rho \,A\,v.}
2757:
2168:
909:Combining equations, the disk loading
2280:
2220:Principles of Helicopter Aerodynamics
2010:
2008:
1766:
1763:
1760:
1341:From the momentum theory, thrust is:
649:{\displaystyle v={\tfrac {1}{2}}\,w.}
38:of the marine air in this photo of a
2729:
1906:26.68 lb/ft (129.63 kg/m)
2739:
2364:Number of helicopters and heliports
2030:
1972:
16:Characteristic of rotors/propellers
13:
2658:Helicopter height–velocity diagram
2005:
675:To compute the disk loading using
267:
14:
2776:
2681:Mars Sample Retrieval Helicopters
1336:
2738:
2728:
2718:
2602:Loss of tail-rotor effectiveness
2464:
2307:Helicopters and other rotorcraft
2255: This article incorporates
2250:
2046:, 2000. Accessed: 17 March 2012.
1854:123,500 lb (56,000 kg)
507:{\displaystyle T={\dot {m}}\,w.}
292:, with uniform induced velocity
2271:Federal Aviation Administration
1900:60,500 lb (27,400 kg)
1876:73,500 lb (33,300 kg)
1860:14.5 lb/ft (71 kg/m)
1832:50,000 lb (22,680 kg)
611:and eliminating terms, we get:
237:Conservation of linear momentum
2587:Mast bumping and other hazards
2139:
2103:
2049:
1838:8.8 lb/ft (43 kg/m)
1814:3.7 lb/ft (18 kg/m)
1789:2.6 lb/ft (14 kg/m)
1398:
1389:
1:
2394:Wire strike protection system
1924:
1882:15 lb/ft (72 kg/m)
1808:3,200 lb (1,451 kg)
272:For an actuator disk of area
162:
2216:Leishman, J. Gordon (2006).
2180:Johnson, Wayne (1994). "2".
312:at the rotor disk, and with
7:
2696:Radio-controlled helicopter
2425:Russian helicopter airlines
2056:Noor, Ahmed Khairy (1996).
1912:
1783:1,370 lb (635 kg)
1736:
10:
2781:
2263:Rotorcraft Flying Handbook
2017:Rotorcraft Flying Handbook
368:through the disk area is:
361:{\displaystyle {\dot {m}}}
233:of a fixed-wing aircraft.
170:contra-rotating propellers
2714:
2640:
2579:
2542:
2473:
2462:
2402:
2321:
2312:
1441:The induced velocity is:
182:
133:
2668:Human-powered helicopter
2555:Manufacturers by country
2447:U.S. Air Force squadrons
2110:Birdsall, David (1996).
1942:Rotary-Wing Aerodynamics
1750:Disk loading comparison
706:, which is equal to the
2415:Active Russian military
2410:Accidents and incidents
1903:2,268 ft (211.4 m)
659:So the velocity of the
205:Alfred George Greenhill
2706:Transverse flow effect
2612:Retreating blade stall
2257:public domain material
2083:Leishman, J. Gordon. "
1746:
1727:
1693:
1620:
1547:
1527:
1496:
1432:
1324:
1218:
1112:
1019:
932:
900:
784:
700:
650:
605:
582:
508:
463:
443:
411:
362:
326:
306:
286:
245:Conservation of energy
77:
54:
43:
2765:Aircraft aerodynamics
1879:4,900 ft (460 m)
1866:CH-53E Super Stallion
1857:8,495 ft (789 m)
1835:5,655 ft (526 m)
1744:
1728:
1694:
1621:
1548:
1528:
1497:
1433:
1325:
1219:
1113:
1020:
933:
931:{\displaystyle T/\,A}
901:
785:
701:
699:{\displaystyle p_{0}}
677:Bernoulli's principle
671:Bernoulli's principle
651:
606:
583:
509:
464:
444:
412:
363:
327:
325:{\displaystyle \rho }
307:
287:
60:
49:
22:
2565:Used in World War II
2432:NATO reporting names
2114:Aircraft Performance
1811:872 ft (81.1 m)
1795:Bell 206B3 JetRanger
1786:497 ft (46.2 m)
1709:
1636:
1560:
1537:
1509:
1448:
1348:
1234:
1128:
1035:
945:
913:
800:
717:
708:atmospheric pressure
683:
618:
595:
524:
476:
453:
433:
375:
343:
316:
296:
276:
249:Conservation of mass
193:disk actuator theory
72:have relatively low
1751:
1726:{\displaystyle T/P}
1526:{\displaystyle T/A}
665:lifting-line theory
126:mode compared to a
2627:Servo transparency
2097:Hofstra University
2090:2005-12-31 at the
1767:Max. disk loading
1761:Max. gross weight
1749:
1747:
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601:
578:
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504:
459:
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407:
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322:
302:
282:
197:mathematical model
138:Disk loading of a
78:
55:
44:
32:blade tip vortices
2752:
2751:
2701:Search and rescue
2622:Vortex ring state
2575:
2574:
2512:Piasecki Aircraft
2502:Juan de la Cierva
2460:
2459:
2184:Helicopter theory
2100:, New York, 2003.
1910:
1909:
1671:
1653:
1611:
1609:
1591:
1546:{\displaystyle P}
1487:
1485:
1467:
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1315:
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1198:
1153:
1103:
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997:
956:
875:
865:
828:
818:
759:
749:
636:
604:{\displaystyle T}
591:Substituting for
559:
546:
494:
462:{\displaystyle T}
442:{\displaystyle w}
387:
355:
305:{\displaystyle v}
285:{\displaystyle A}
231:lift-induced drag
96:change across an
2772:
2742:
2741:
2732:
2731:
2722:
2691:List of aircraft
2597:Ground resonance
2592:Dynamic rollover
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1985:Montreal, Quebec
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1764:Total disk area
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155:. Typically, an
40:vertical takeoff
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2724:Aviation portal
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2676:Mars helicopter
2636:
2607:Low-g condition
2571:
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2519:Fairey Rotodyne
2507:Skyworks Global
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2359:Flight controls
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2092:Wayback Machine
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942:
919:
914:
911:
910:
887:
883:
866:
854:
850:
840:
836:
819:
807:
803:
801:
798:
797:
771:
767:
750:
738:
734:
724:
720:
718:
715:
714:
690:
686:
684:
681:
680:
673:
627:
619:
616:
615:
596:
593:
592:
568:
564:
563:
551:
550:
537:
525:
522:
521:
486:
485:
477:
474:
473:
454:
451:
450:
434:
431:
430:
379:
378:
376:
373:
372:
347:
346:
344:
341:
340:
317:
314:
313:
297:
294:
293:
277:
274:
273:
270:
268:Momentum theory
258:compressibility
189:momentum theory
185:
165:
151:performance in
136:
92:is the average
17:
12:
11:
5:
2778:
2768:
2767:
2750:
2749:
2747:
2746:
2736:
2726:
2715:
2712:
2711:
2709:
2708:
2703:
2698:
2693:
2688:
2683:
2678:
2670:
2665:
2660:
2655:
2650:
2644:
2642:
2638:
2637:
2635:
2634:
2629:
2624:
2619:
2614:
2609:
2604:
2599:
2594:
2589:
2583:
2581:
2577:
2576:
2573:
2572:
2570:
2569:
2568:
2567:
2562:
2557:
2546:
2544:
2540:
2539:
2537:
2536:
2531:
2526:
2521:
2516:
2515:
2514:
2509:
2504:
2499:
2488:
2486:
2479:
2471:
2470:
2463:
2461:
2458:
2457:
2455:
2454:
2449:
2444:
2439:
2437:Prison escapes
2434:
2429:
2428:
2427:
2417:
2412:
2406:
2404:
2400:
2399:
2397:
2396:
2391:
2386:
2384:Rotor solidity
2381:
2376:
2371:
2366:
2361:
2356:
2351:
2346:
2341:
2336:
2331:
2325:
2323:
2316:
2310:
2309:
2304:
2303:
2296:
2289:
2281:
2246:
2245:
2230:
2208:
2198:
2167:
2156:
2138:
2128:
2102:
2076:
2066:
2048:
2029:
2004:
1971:
1952:
1929:
1928:
1926:
1923:
1922:
1921:
1914:
1911:
1908:
1907:
1904:
1901:
1898:
1890:
1884:
1883:
1880:
1877:
1874:
1868:
1862:
1861:
1858:
1855:
1852:
1846:
1840:
1839:
1836:
1833:
1830:
1822:
1820:CH-47D Chinook
1816:
1815:
1812:
1809:
1806:
1797:
1791:
1790:
1787:
1784:
1781:
1777:Light utility
1775:
1769:
1768:
1765:
1762:
1759:
1756:
1738:
1735:
1722:
1718:
1714:
1700:
1699:
1688:
1683:
1680:
1675:
1670:
1667:
1662:
1657:
1652:
1649:
1644:
1641:
1627:
1626:
1615:
1607:
1604:
1600:
1595:
1590:
1587:
1580:
1577:
1574:
1571:
1568:
1565:
1542:
1522:
1518:
1514:
1503:
1502:
1491:
1483:
1480:
1476:
1471:
1466:
1463:
1456:
1453:
1439:
1438:
1427:
1422:
1418:
1413:
1409:
1406:
1403:
1400:
1397:
1394:
1391:
1384:
1381:
1375:
1372:
1365:
1362:
1356:
1353:
1338:
1337:Power required
1335:
1331:
1330:
1319:
1314:
1311:
1303:
1300:
1293:
1288:
1284:
1279:
1274:
1270:
1265:
1258:
1255:
1249:
1244:
1240:
1225:
1224:
1213:
1208:
1205:
1197:
1194:
1187:
1182:
1178:
1173:
1168:
1164:
1159:
1152:
1149:
1143:
1138:
1134:
1119:
1118:
1107:
1102:
1099:
1094:
1089:
1085:
1080:
1075:
1071:
1066:
1059:
1056:
1050:
1045:
1041:
1026:
1025:
1012:
1008:
1003:
996:
993:
987:
982:
978:
973:
968:
964:
960:
955:
952:
927:
922:
918:
907:
906:
895:
890:
886:
881:
874:
871:
862:
857:
853:
848:
843:
839:
834:
827:
824:
815:
810:
806:
791:
790:
779:
774:
770:
765:
758:
755:
746:
741:
737:
732:
727:
723:
693:
689:
672:
669:
657:
656:
645:
642:
635:
632:
626:
623:
600:
589:
588:
577:
571:
567:
558:
555:
545:
542:
536:
533:
529:
515:
514:
503:
500:
493:
490:
484:
481:
458:
438:
418:
417:
406:
403:
399:
395:
392:
386:
383:
354:
351:
338:mass flow rate
334:density of air
321:
301:
281:
269:
266:
227:kinetic energy
201:W.J.M. Rankine
184:
181:
164:
161:
135:
132:
82:fluid dynamics
64:light utility
62:Piston-powered
15:
9:
6:
4:
3:
2:
2777:
2766:
2763:
2762:
2760:
2745:
2737:
2735:
2727:
2725:
2721:
2717:
2716:
2713:
2707:
2704:
2702:
2699:
2697:
2694:
2692:
2689:
2687:
2684:
2682:
2679:
2677:
2675:
2671:
2669:
2666:
2664:
2661:
2659:
2656:
2654:
2651:
2649:
2648:Bamboo-copter
2646:
2645:
2643:
2639:
2633:
2630:
2628:
2625:
2623:
2620:
2618:
2617:Dynamic stall
2615:
2613:
2610:
2608:
2605:
2603:
2600:
2598:
2595:
2593:
2590:
2588:
2585:
2584:
2582:
2578:
2566:
2563:
2561:
2560:Most-produced
2558:
2556:
2553:
2552:
2551:
2548:
2547:
2545:
2541:
2535:
2532:
2530:
2527:
2525:
2522:
2520:
2517:
2513:
2510:
2508:
2505:
2503:
2500:
2498:
2495:
2494:
2493:
2490:
2489:
2487:
2483:
2480:
2478:
2472:
2467:
2453:
2452:U.S. military
2450:
2448:
2445:
2443:
2440:
2438:
2435:
2433:
2430:
2426:
2423:
2422:
2421:
2418:
2416:
2413:
2411:
2408:
2407:
2405:
2401:
2395:
2392:
2390:
2387:
2385:
2382:
2380:
2377:
2375:
2372:
2370:
2369:Manufacturers
2367:
2365:
2362:
2360:
2357:
2355:
2352:
2350:
2347:
2345:
2342:
2340:
2337:
2335:
2332:
2330:
2327:
2326:
2324:
2320:
2317:
2315:
2311:
2302:
2297:
2295:
2290:
2288:
2283:
2282:
2279:
2275:
2272:
2265:
2264:
2258:
2241:
2237:
2233:
2231:0-521-85860-7
2227:
2222:
2221:
2212:
2205:
2201:
2199:0-486-68230-7
2195:
2191:
2186:
2185:
2176:
2174:
2172:
2164:
2159:
2157:3-540-42696-5
2153:
2149:
2142:
2135:
2131:
2129:0-521-56836-6
2125:
2121:
2116:
2115:
2106:
2099:
2098:
2093:
2089:
2086:
2080:
2073:
2069:
2067:1-56347-188-4
2063:
2059:
2052:
2045:
2044:
2039:
2033:
2026:
2019:
2018:
2011:
2009:
2001:
1995:
1994:10.1.1.45.612
1990:
1986:
1982:
1975:
1968:
1963:
1959:
1955:
1953:0-486-64647-5
1949:
1944:
1943:
1934:
1930:
1920:
1917:
1916:
1905:
1902:
1899:
1897:
1894:
1891:
1889:
1888:MV-22B Osprey
1886:
1885:
1881:
1878:
1875:
1873:
1869:
1867:
1864:
1863:
1859:
1856:
1853:
1851:
1847:
1845:
1842:
1841:
1837:
1834:
1831:
1829:
1826:
1823:
1821:
1818:
1817:
1813:
1810:
1807:
1805:
1801:
1798:
1796:
1793:
1792:
1788:
1785:
1782:
1780:
1776:
1774:
1771:
1770:
1757:
1754:
1753:
1743:
1734:
1720:
1716:
1712:
1705:
1704:power loading
1686:
1681:
1678:
1673:
1668:
1665:
1660:
1655:
1650:
1647:
1642:
1639:
1632:
1631:
1630:
1613:
1605:
1602:
1598:
1593:
1588:
1585:
1578:
1575:
1572:
1569:
1566:
1563:
1556:
1555:
1554:
1540:
1520:
1516:
1512:
1489:
1481:
1478:
1474:
1469:
1464:
1461:
1454:
1451:
1444:
1443:
1442:
1425:
1420:
1416:
1411:
1407:
1404:
1401:
1395:
1392:
1382:
1379:
1373:
1370:
1363:
1360:
1354:
1351:
1344:
1343:
1342:
1334:
1317:
1312:
1309:
1301:
1298:
1291:
1286:
1282:
1277:
1272:
1268:
1263:
1256:
1253:
1247:
1242:
1238:
1230:
1229:
1228:
1211:
1206:
1203:
1195:
1192:
1185:
1180:
1176:
1171:
1166:
1162:
1157:
1150:
1147:
1141:
1136:
1132:
1124:
1123:
1122:
1105:
1100:
1097:
1092:
1087:
1083:
1078:
1073:
1069:
1064:
1057:
1054:
1048:
1043:
1039:
1031:
1030:
1029:
1010:
1006:
1001:
994:
991:
985:
980:
976:
971:
966:
962:
958:
953:
950:
941:
940:
939:
925:
920:
916:
893:
888:
884:
879:
872:
869:
860:
855:
851:
846:
841:
837:
832:
825:
822:
813:
808:
804:
796:
795:
794:
777:
772:
768:
763:
756:
753:
744:
739:
735:
730:
725:
721:
713:
712:
711:
709:
691:
687:
678:
668:
666:
662:
643:
640:
633:
630:
624:
621:
614:
613:
612:
598:
575:
569:
565:
556:
553:
543:
540:
534:
531:
527:
520:
519:
518:
501:
498:
491:
488:
482:
479:
472:
471:
470:
456:
436:
428:
423:
404:
401:
397:
393:
390:
384:
381:
371:
370:
369:
352:
349:
339:
335:
319:
299:
279:
265:
263:
259:
255:
250:
246:
242:
238:
234:
232:
228:
223:
221:
217:
214:
210:
206:
202:
198:
194:
190:
180:
178:
173:
171:
160:
158:
154:
150:
144:
141:
131:
129:
125:
121:
118:
114:
110:
106:
103:
99:
98:actuator disk
95:
91:
87:
83:
76:disk loading.
75:
71:
67:
63:
59:
52:
51:C-27J Spartan
48:
41:
37:
33:
29:
26:
21:
2673:
2497:CarterCopter
2349:Disk loading
2348:
2339:Autorotation
2262:
2249:
2219:
2211:
2203:
2183:
2161:
2147:
2141:
2133:
2113:
2105:
2095:
2079:
2071:
2057:
2051:
2041:
2032:
2024:
2016:
1998:
1980:
1974:
1965:
1941:
1933:
1919:Wing loading
1825:Tandem rotor
1773:Robinson R22
1758:Description
1701:
1628:
1504:
1440:
1340:
1332:
1226:
1120:
1027:
908:
792:
674:
658:
590:
516:
419:
271:
260:of the air,
235:
224:
211:(1889). The
195:describes a
192:
188:
186:
177:Airbus A400M
174:
166:
149:autorotation
145:
137:
90:disc loading
89:
86:disk loading
85:
79:
70:Robinson R22
36:condensation
25:MV-22 Osprey
2744:WikiProject
2442:Ultralights
2314:Helicopters
1870:Heavy-lift
1848:Heavy-lift
209:R.E. Froude
207:(1888) and
117:V-22 Osprey
109:tail rotors
105:main rotors
66:helicopters
2632:Tailstrike
2550:Rotorcraft
2534:Rotor kite
2529:Monocopter
2477:rotorcraft
2329:Amphibious
2094:" page 5.
1987:, Canada.
1967:airscrews.
1925:References
1872:helicopter
1850:helicopter
1828:helicopter
1804:helicopter
1800:Turboshaft
1779:helicopter
661:slipstream
427:slipstream
422:slipstream
262:frictional
213:helicopter
163:Propellers
153:rotorcraft
130:aircraft.
124:fixed-wing
113:propellers
102:helicopter
74:main rotor
68:like this
2686:Jesus nut
2674:Ingenuity
2653:Cyclogyro
1989:CiteSeerX
1962:565962623
1893:Tiltrotor
1844:Mil Mi-26
1755:Aircraft
1679:−
1606:ρ
1594:⋅
1482:ρ
1470:⋅
1408:ρ
1383:˙
1364:˙
1264:ρ
1186:−
1158:ρ
1142:−
1065:ρ
1002:ρ
972:−
880:ρ
833:ρ
764:ρ
557:˙
492:˙
394:ρ
385:˙
353:˙
320:ρ
254:Viscosity
241:mass flow
128:turboprop
120:tiltrotor
28:tiltrotor
2759:Category
2663:Helitack
2524:Gyrodyne
2492:Autogyro
2485:Articles
2420:Airlines
2374:Military
2354:Dynamics
2344:Backpack
2322:Articles
2240:61463625
2088:Archived
2000:systems.
1913:See also
1802:utility
1737:Examples
220:hovering
203:(1865),
157:autogyro
140:hovering
94:pressure
2734:Commons
2641:Related
2580:Hazards
2389:Utility
332:as the
2334:Attack
2238:
2228:
2196:
2154:
2126:
2064:
1991:
1960:
1950:
1896:V/STOL
1505:Where
864:
817:
748:
336:, the
183:Theory
134:Rotors
2543:Lists
2474:Other
2403:Lists
2379:Rotor
2267:(PDF)
2259:from
2192:–34.
2163:C160.
2021:(PDF)
216:rotor
34:from
2236:OCLC
2226:ISBN
2194:ISBN
2152:ISBN
2124:ISBN
2062:ISBN
2043:NASA
2040:p2.
1958:OCLC
1948:ISBN
938:is:
256:and
187:The
175:The
107:and
23:The
191:or
88:or
80:In
2761::
2269:.
2234:.
2202:.
2190:28
2170:^
2160:.
2132:.
2122:.
2120:99
2070:.
2007:^
1997:.
1964:.
1956:.
1733:.
667:.
243:.
111:;
84:,
2300:e
2293:t
2286:v
2273:.
2242:.
1721:P
1717:/
1713:T
1687:.
1682:1
1674:]
1669:P
1666:T
1661:[
1656:=
1651:T
1648:P
1643:=
1640:v
1614:.
1603:2
1599:1
1589:A
1586:T
1579:T
1576:=
1573:v
1570:T
1567:=
1564:P
1541:P
1521:A
1517:/
1513:T
1490:.
1479:2
1475:1
1465:A
1462:T
1455:=
1452:v
1426:.
1421:2
1417:v
1412:A
1405:2
1402:=
1399:)
1396:v
1393:2
1390:(
1380:m
1374:=
1371:w
1361:m
1355:=
1352:T
1318:.
1313:A
1310:T
1302:4
1299:3
1292:+
1287:0
1283:p
1278:=
1273:2
1269:v
1257:2
1254:3
1248:+
1243:0
1239:p
1212:.
1207:A
1204:T
1196:4
1193:1
1181:0
1177:p
1172:=
1167:2
1163:v
1151:2
1148:1
1137:0
1133:p
1106:.
1101:A
1098:T
1093:+
1088:0
1084:p
1079:=
1074:2
1070:w
1058:2
1055:1
1049:+
1044:0
1040:p
1011:2
1007:w
995:2
992:1
986:=
981:1
977:p
967:2
963:p
959:=
954:A
951:T
926:A
921:/
917:T
894:.
889:2
885:w
873:2
870:1
861:+
856:0
852:p
847:=
842:2
838:v
826:2
823:1
814:+
809:2
805:p
778:.
773:2
769:v
757:2
754:1
745:+
740:1
736:p
731:=
726:0
722:p
692:0
688:p
644:.
641:w
634:2
631:1
625:=
622:v
599:T
576:.
570:2
566:w
554:m
544:2
541:1
535:=
532:v
528:T
502:.
499:w
489:m
483:=
480:T
457:T
437:w
405:.
402:v
398:A
391:=
382:m
350:m
300:v
280:A
42:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
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