20:
198:(rpm), typically above 4,000 rpm. Traditional aircraft engines, where the propeller is most commonly fastened directly to the engine crankshaft, develop peak power near the peak safe and efficient speed for the propeller—2,500 to 3,000 rpm. This speed is considered the typical maximum rpm for a single-engine aircraft propeller due to the need to keep the propeller tip speed below the speed of sound.
166:
to increase rapidly to high levels at certain rotational speeds. Measures taken by the designer to mitigate torsional resonances in the original design of the engine can be rendered ineffective if the resonant frequency is altered by the use of a reduction unit. Clutches and/or flexible couplings are
63:
recognised the need for propeller reduction gearing in 1903, but it was not generally used on aircraft engines until larger engines were designed in the 1920s. Large engines with high crankshaft speeds and power outputs demanded propeller reduction, pilots noted the increase in performance of
186:
The use of propeller reduction gearing was very common during the height of piston engine use in aviation (the 1930s through the 1940s), with essentially all of the most powerful piston engines ever built for use in aircraft being designed to make use of reduction gearing.
194:
when automotive engines may be used. These engines, in addition to their lower cost, typically have less displacement than purpose-built light aircraft engines and develop peak power at high
73:
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377:
970:
963:
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162:
that can develop at certain speeds. The load of a propeller and reduction unit can alter the resonant frequencies of the crankshaft, allowing
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for twin-engined aircraft, a much cheaper method than designing and building the engines to run in opposite directions.
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Factory-certified aircraft engines have also used reduction units integral to their design. The
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The challenge with coupling gearboxes to internal combustion engines is primarily the torsional
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43:(rpm) from the higher input rpm of the powerplant. This allows the use of small
1006:
883:
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engine from the same company used opposite rotation reduction gears to provide
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385:
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sometimes used to prevent torsional resonance from reaching damaging levels.
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The use of a reduction unit is common in the construction of experimental
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engines used a single gearset to drive both the propeller and the
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88:
1209:
1065:
500:
470:
144:
140:
96:
178:, this allowed the propeller to run at half the engine speed.
1389:
863:
230:
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330:. Cambridge, England. Patrick Stephens Limited, 2006.
39:
or a belt and pulley device used to reduce the output
1357:Engine-indicating and crew-alerting system (EICAS)
80:Types of propeller speed reduction units include:
1390:Full Authority Digital Engine/Electronics (FADEC)
280:
147:, thus protecting the reduction gears. The later
1474:
64:similar aircraft fitted with reduction gearing.
1347:Electronic centralised aircraft monitor (ECAM)
217:twins, among others, used the geared Lycoming
139:propeller reduction gearing which contained a
971:
371:
1352:Electronic flight instrument system (EFIS)
978:
964:
378:
364:
273:
271:
269:
267:
205:used a geared unit which is part of the
71:
54:
23:The propeller speed reduction unit of a
18:
323:No. 1935, Volume XLIX, 24 January 1946.
1475:
344:. London: Wm. Carling & Co, 1969.
264:
959:
359:
237:which incorporates a geared reducer.
126:
47:internal combustion engines to turn
392:components, systems and terminology
13:
328:Development of Piston Aero Engines
14:
1499:
51:within an efficient speed range.
1220:Thrust specific fuel consumption
311:
181:
1269:Propeller speed reduction unit
714:Propeller speed reduction unit
298:
289:
143:designed to limit the maximum
33:propeller speed reduction unit
1:
252:
524:Capacitor discharge ignition
7:
1180:Engine pressure ratio (EPR)
342:The Shuttleworth Collection
240:
153:counter-rotating propellers
10:
1504:
1447:Auxiliary power unit (APU)
1076:Rotating detonation engine
76:Simple spur gear reduction
1434:
1408:
1375:
1332:
1277:
1256:
1247:
1147:
1084:
1014:
1000:
917:
851:
828:
782:
727:
701:
692:
567:
534:Electronic fuel injection
509:
406:
397:
1488:Mechanisms (engineering)
1155:Aircraft engine starting
580:Aircraft engine starting
257:
172:Continental Tiara series
135:engine of 1915 featured
67:
1036:Pulse detonation engine
625:Mean effective pressure
295:Flight 1946, pp. 92–94.
1225:Thrust to weight ratio
1195:Overall pressure ratio
1190:Jet engine performance
1114:Centrifugal compressor
1031:Gluhareff Pressure Jet
665:Time between overhauls
196:revolutions per minute
77:
41:revolutions per minute
28:
1462:Ice protection system
1230:Variable cycle engine
1200:Propulsive efficiency
940:Ice protection system
680:Volumetric efficiency
645:Overhead valve engine
304:Gunston 2006, p. 191.
75:
55:History and operation
22:
1362:Flight data recorder
1124:Constant speed drive
1104:Afterburner (reheat)
925:Auxiliary power unit
805:Flight data recorder
277:Gunston 2006, p. 82.
227:light sport aircraft
87:Single reduction or
894:Pressure carburetor
630:Naturally aspirated
600:Engine displacement
286:Guttery 1969, p.27.
164:torsional vibration
112:Fixed internal gear
49:aircraft propellers
1264:Propeller governor
909:Updraft carburetor
783:Engine instruments
709:Propeller governor
605:Four-stroke engine
207:Continental GO-300
192:homebuilt aircraft
133:Rolls-Royce Falcon
93:Internal spur gear
78:
29:
1470:
1469:
1342:Annunciator panel
1328:
1327:
1243:
1242:
1134:Propelling nozzle
953:
952:
790:Annunciator panel
778:
777:
688:
687:
670:Two-stroke engine
640:Overhead camshaft
620:Manifold pressure
590:Compression ratio
229:use engines from
209:engine while the
127:Design variations
121:Epicyclic gearing
16:Mechanical device
1495:
1457:Hydraulic system
1452:Bleed air system
1442:Air-start system
1305:Counter-rotating
1254:
1253:
1235:Windmill restart
1205:Specific impulse
1175:Compressor stall
1109:Axial compressor
1012:
1011:
980:
973:
966:
957:
956:
935:Hydraulic system
755:Counter-rotating
699:
698:
451:Hydraulic tappet
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1471:
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1413:
1404:
1400:Thrust reversal
1377:Engine controls
1371:
1334:
1324:
1300:Contra-rotating
1273:
1239:
1143:
1094:Accessory drive
1086:
1080:
1022:Air turborocket
1004:
996:
984:
954:
949:
930:Coffman starter
913:
856:
847:
838:Carburetor heat
830:Engine controls
824:
774:
750:Contra-rotating
723:
684:
615:Ignition timing
563:
544:Ignition system
511:
505:
408:
393:
384:
354:
326:Gunston, Bill.
314:
309:
308:
303:
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243:
184:
129:
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61:Wright brothers
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12:
11:
5:
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1320:Variable-pitch
1317:
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1295:Constant-speed
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1007:jet propulsion
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884:Inlet manifold
881:
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874:Fuel injection
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770:Variable-pitch
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745:Constant-speed
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463:
461:Obturator ring
458:
453:
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433:
428:
423:
421:Connecting rod
418:
412:
410:
401:
399:Piston engines
395:
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383:
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368:
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353:
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340:Guttery, T.E.
338:
324:
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109:Fixed sun gear
107:
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56:
53:
15:
9:
6:
4:
3:
2:
1500:
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1460:
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1437:
1435:Other systems
1433:
1427:
1424:
1422:
1419:
1418:
1416:
1412:and induction
1411:
1407:
1401:
1398:
1396:
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1367:Glass cockpit
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1165:Brayton cycle
1163:
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1146:
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1139:Turbine blade
1137:
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943:
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926:
923:
922:
920:
918:Other systems
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895:
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890:
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865:
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859:
855:and induction
854:
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844:
841:
839:
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831:
827:
821:
818:
816:
813:
811:
810:Glass cockpit
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663:
661:
658:
656:
655:Shock cooling
653:
651:
650:Rotary engine
648:
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550:
547:
545:
542:
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537:
535:
532:
530:
529:Dual ignition
527:
525:
522:
520:
517:
516:
514:
508:
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497:
494:
492:
489:
487:
484:
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479:
477:
474:
472:
469:
467:
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462:
459:
457:
454:
452:
449:
447:
444:
442:
441:Cylinder head
439:
437:
434:
432:
429:
427:
424:
422:
419:
417:
414:
413:
411:
405:
402:
400:
396:
391:
390:piston engine
388:
381:
376:
374:
369:
367:
362:
361:
358:
351:
350:0-901319-01-5
347:
343:
339:
337:
336:0-7509-4478-1
333:
329:
325:
322:
321:
317:
316:
301:
292:
283:
274:
272:
270:
268:
263:
248:
245:
244:
238:
236:
232:
228:
224:
220:
216:
212:
211:Helio Courier
208:
204:
199:
197:
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188:
179:
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173:
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165:
161:
156:
154:
150:
146:
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98:
95:
92:
90:
86:
83:
82:
81:
74:
65:
62:
52:
50:
46:
42:
38:
34:
26:
25:Rolls-Royce R
21:
1421:Flame holder
1395:Thrust lever
1385:Autothrottle
1268:
1215:Thrust lapse
1170:Bypass ratio
1002:Gas turbines
994:gas turbines
945:Recoil start
904:Turbocharger
899:Supercharger
765:Single-blade
713:
675:Valve timing
496:Sleeve valve
481:Poppet valve
456:Main bearing
341:
327:
318:
312:Bibliography
300:
291:
282:
233:such as the
213:and several
200:
189:
185:
182:Applications
169:
157:
130:
79:
58:
45:displacement
32:
30:
1335:instruments
1290:Blade pitch
1285:Autofeather
987:Jet engines
889:Intercooler
815:Hobbs meter
740:Blade pitch
735:Autofeather
728:Terminology
635:Monosoupape
595:Dead centre
568:Terminology
476:Piston ring
446:Gudgeon pin
84:Chain drive
1483:Propellers
1477:Categories
1278:Principles
1257:Components
1249:Propellers
1148:Principles
1099:Air intake
1087:components
1085:Mechanical
1061:Turboshaft
879:Gascolator
869:Carburetor
820:Tachometer
702:Components
694:Propellers
610:Horsepower
575:Air-cooled
554:Spark plug
519:Alternator
512:components
510:Electrical
491:Rocker arm
431:Crankshaft
409:components
407:Mechanical
253:References
247:Ultralight
215:Beechcraft
203:Cessna 175
116:Belt drive
1310:Proprotor
1160:Bleed air
1119:Combustor
1056:Turboprop
539:Generator
235:Rotax 912
160:resonance
137:epicyclic
104:planetary
89:spur gear
1426:Jet fuel
1315:Scimitar
1185:Flameout
1129:Impeller
1051:Turbojet
1046:Turbofan
1027:Pulsejet
991:aircraft
843:Throttle
760:Scimitar
466:Oil pump
436:Cylinder
426:Crankpin
416:Camshaft
387:Aircraft
241:See also
176:camshaft
1414:systems
1041:Propfan
719:Spinner
559:Starter
549:Magneto
486:Pushrod
225:. Many
37:gearbox
1333:Engine
1210:Thrust
1071:Rocket
1066:Ramjet
857:system
660:Stroke
501:Tappet
471:Piston
348:
334:
320:Flight
223:GO-480
219:GO-435
149:Merlin
145:torque
141:clutch
97:Farman
27:engine
1015:Types
864:Avgas
800:EICAS
258:Notes
231:Rotax
101:bevel
68:Types
35:is a
1410:Fuel
1005:and
989:and
853:Fuel
795:EFIS
585:Bore
346:ISBN
332:ISBN
221:and
170:The
131:The
106:type
59:The
99:or
1479::
266:^
31:A
1029:/
979:e
972:t
965:v
379:e
372:t
365:v
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