52:
86:
82:, low airspeeds, low temperature differences and small mass flows make that unlikely, particularly when combined with the lack of flow control as the air exits the cowling. Although superior to earlier cowlings, and uncowled engines in terms of drag and cooling, above 217 kn (402 km/h; 250 mph) the NACA cowling was more efficient and soon replaced it in general use.
20:
74:
in 1929. In the United States it was often called a "drag ring". It caused a reduction in the drag of radial engines and was widely used in high-speed designs of 1930–1935, before the long-chord
167:
153:
60:
338:
67:
261:
915:
561:
51:
1289:
43:
to reduce drag and improve cooling. It was patented in 1929, and found use on various aircraft of the 1930s and into the 1940s.
229:
955:
133:
The wing engines of the Ju 52 had longer NACA cowlings, but the central engine only had space for the shorter
Townend ring.
910:
855:
720:
93:
Ju 52/3m being serviced in Crete in 1943: Note the narrow-chord
Townend ring on the central engine and the deeper-chord
975:
331:
198:
745:
85:
945:
543:
193:"A History of Aircraft Piston Engines" by Herschel Smith, (Sunflower University Press Manhattan, Kansas, 1981,
1238:
1228:
1069:
324:
216:
Chapter 5: High-speed
Cowlings, Air Inlets and Outlets, and Internal-Flow Systems: The ramjet investigation
301:
285:
268:
950:
905:
596:
1136:
980:
930:
920:
473:
403:
234:
From
Engineering Science to Big Science: The NACA and NASA Collier Trophy Research Project Winners
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79:
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830:
388:
383:
64:
1034:
180:
1283:
1182:
1121:
925:
860:
498:
478:
393:
230:"Engineering Science and the Development of the NACA Low-Drag Engine Cowling"
114:
40:
1218:
1146:
1109:
1079:
1054:
1019:
800:
770:
740:
706:
686:
676:
671:
641:
576:
443:
413:
373:
110:
94:
75:
181:"Means for reducing eddy formation in the airflow passing aircraft bodies"
1166:
1049:
765:
621:
212:
The high-speed frontier: Case histories of four NACA programs, 1920–1950
1156:
1044:
1039:
995:
990:
825:
760:
735:
691:
666:
651:
586:
448:
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158:, 8 July 1933 (amended specification from original dated 10 July 1928).
24:
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1024:
880:
661:
646:
626:
581:
566:
523:
508:
493:
428:
398:
90:
155:
Patent
Specification 320131: Improvements in or relating to aircraft
1126:
1099:
1074:
840:
820:
681:
611:
528:
453:
423:
359:
900:
551:
533:
458:
269:"Engine Cowling: With Special Reference to the Air-cooled Engine"
78:
came into general use. Despite suggestions of it exploiting the
606:
513:
488:
418:
168:
1930 Canadian patent CA 304755 by Hubert
Townend with drawings
1029:
631:
483:
19:
39:
cowling ring fitted around the cylinders of an aircraft
101:
Examples of aircraft with
Townend rings include the
346:
1281:
59:The Townend ring was the invention of Dr.
332:
290:The Aircraft Engineer (Supplement to Flight)
273:The Aircraft Engineer (Supplement to Flight)
227:
339:
325:
312:(7): 157–158, 15 February 1934, No. 1312
84:
50:
18:
1282:
284:North, J. D. (22 February 1934),
320:
283:
267:North, J. D. (8 February 1934),
266:
204:
55:An Argosy in 1929, with townend rings
70:in 1929. Patents were supported by
13:
14:
1301:
255:
1290:Aircraft propulsion components
1249:In-flight entertainment system
946:Horizontal situation indicator
221:
187:
173:
161:
147:
127:
113:and the central engine on the
46:
1:
140:
1229:Environmental control system
68:National Physical Laboratory
7:
10:
1306:
906:Course deviation indicator
597:Electro-hydraulic actuator
16:Propeller aircraft cowling
1196:
1175:
1137:Conventional landing gear
1108:
1004:
839:
705:
542:
358:
921:Flight management system
120:
1224:Emergency oxygen system
986:Turn and slip indicator
781:Leading-edge droop flap
751:Drag-reducing aerospike
726:Adaptive compliant wing
721:Active Aeroelastic Wing
214:, SP-445, NASA (1980),
1264:Passenger service unit
1065:Self-sealing fuel tank
961:Multi-function display
296:(2): 174a–174f, No. 97
279:(6): 133–137, No. 1311
103:Boeing P-26 Peashooter
98:
72:Boulton & Paul Ltd
56:
28:
1244:Ice protection system
1162:Tricycle landing gear
1152:Landing gear extender
369:Aft pressure bulkhead
262:The Spotters Glossary
88:
54:
22:
1209:Auxiliary power unit
617:Flight control modes
97:on the wing engines.
23:Polish sports plane
1188:Escape crew capsule
1095:War emergency power
966:Pitot–static system
811:Variable-sweep wing
519:Vertical stabilizer
27:with a Townend ring
896:Attitude indicator
876:Airspeed indicator
871:Aircraft periscope
99:
57:
29:
1277:
1276:
1204:Aircraft lavatory
941:Heading indicator
886:Annunciator panel
866:Air data computer
776:Leading-edge cuff
228:Hansen, James R.
210:Becker, J.;
107:Vickers Wellesley
1297:
1259:Navigation light
1239:Hydraulic system
1214:Bleed air system
1142:Drogue parachute
816:Vortex generator
434:Interplane strut
341:
334:
327:
318:
317:
313:
302:"Engine Cowling"
297:
286:"Engine Cowling"
280:
249:
248:
246:
245:
236:. Archived from
225:
219:
208:
202:
191:
185:
184:
177:
171:
165:
159:
151:
134:
131:
1305:
1304:
1300:
1299:
1298:
1296:
1295:
1294:
1280:
1279:
1278:
1273:
1269:Ram air turbine
1234:Flight recorder
1192:
1171:
1104:
1085:Thrust reversal
1009:
1000:
971:Radar altimeter
936:Head-up display
846:
835:
731:Anti-shock body
713:
701:
562:Artificial feel
544:Flight controls
538:
404:Fabric covering
354:
350:components and
345:
300:
258:
253:
252:
243:
241:
226:
222:
209:
205:
201:), 255 pp.
192:
188:
179:
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80:Meredith effect
49:
17:
12:
11:
5:
1303:
1293:
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1274:
1272:
1271:
1266:
1261:
1256:
1254:Landing lights
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1216:
1211:
1206:
1200:
1198:
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1185:
1179:
1177:
1176:Escape systems
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1172:
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1164:
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1154:
1149:
1144:
1139:
1134:
1129:
1124:
1118:
1116:
1114:arresting gear
1106:
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1103:
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1097:
1092:
1087:
1082:
1077:
1072:
1070:Splitter plate
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396:
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389:Cruciform tail
386:
384:Crack arrestor
381:
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365:
363:
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256:External links
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186:
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160:
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61:Hubert Townend
48:
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15:
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4:
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1202:
1201:
1199:
1197:Other systems
1195:
1189:
1186:
1184:
1183:Ejection seat
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1180:
1178:
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1165:
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1135:
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1127:Arrestor hook
1125:
1123:
1122:Aircraft tire
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927:
926:Glass cockpit
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861:Air data boom
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643:
642:Rudder pedals
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505:
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499:Trailing edge
497:
495:
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485:
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480:
479:Stressed skin
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260:
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240:on 2004-10-31
239:
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217:
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207:
200:
199:0-89745-079-5
196:
190:
182:
176:
169:
164:
157:
156:
150:
146:
130:
126:
118:
116:
115:Junkers Ju 52
112:
108:
104:
96:
95:NACA cowlings
92:
87:
83:
81:
77:
73:
69:
66:
62:
53:
44:
42:
41:radial engine
38:
34:
26:
21:
1219:Deicing boot
1147:Landing gear
1090:Townend ring
1089:
1080:Thrust lever
1055:NACA cowling
1020:Autothrottle
1012:fuel systems
1010:devices and
801:Stall strips
771:Krueger flap
741:Channel wing
687:Wing warping
677:Stick shaker
672:Stick pusher
592:Dual control
577:Centre stick
444:Leading edge
414:Flying wires
374:Cabane strut
309:
305:
293:
289:
276:
272:
242:. Retrieved
238:the original
233:
223:
211:
206:
189:
175:
163:
154:
149:
129:
111:Fokker D.XVI
100:
76:NACA cowling
58:
35:is a narrow-
33:Townend ring
32:
30:
1167:Tundra tire
1050:Intake ramp
981:Transponder
766:Gurney flap
707:Aerodynamic
622:Fly-by-wire
504:Triple tail
47:Development
1157:Oleo strut
1045:Inlet cone
1040:Gascolator
1006:Propulsion
996:Yaw string
991:Variometer
847:instrument
826:Wing fence
761:Gouge flap
736:Blown flap
692:Yaw damper
667:Stabilator
652:Side-stick
587:Dive brake
474:Stabilizer
449:Lift strut
439:Jury strut
244:2007-04-28
141:References
1132:Autobrake
1060:NACA duct
1035:Fuel tank
1025:Drop tank
1008:controls,
891:Astrodome
881:Altimeter
746:Dog-tooth
711:high-lift
662:Spoileron
647:Servo tab
627:Gust lock
582:Deceleron
567:Autopilot
524:Wing root
509:Twin tail
494:Tailplane
429:Hardpoint
399:Empennage
362:structure
91:Luftwaffe
1284:Category
1100:Wet wing
1075:Throttle
821:Vortilon
682:Trim tab
612:Flaperon
602:Elevator
557:Airbrake
529:Wing tip
454:Longeron
424:Fuselage
360:Airframe
348:Aircraft
1110:Landing
901:Compass
849:systems
841:Avionic
831:Winglet
714:devices
657:Spoiler
552:Aileron
534:Wingbox
459:Nacelle
409:Fairing
352:systems
65:British
63:of the
25:PZL Ł.2
845:flight
806:Strake
637:Rudder
607:Elevon
572:Canard
514:V-tail
489:T-tail
419:Former
379:Canopy
306:Flight
197:
109:, the
105:, the
1030:FADEC
916:EICAS
791:Slats
632:HOTAS
484:Strut
121:Notes
117:/3m.
37:chord
1112:and
976:TCAS
956:ISIS
911:EFIS
856:ACAS
843:and
796:Slot
756:Flap
709:and
697:Yoke
469:Spar
394:Dope
310:XXVI
277:XXIV
195:ISBN
951:INS
931:GPS
786:LEX
464:Rib
1286::
308:,
304:,
294:IX
292:,
288:,
275:,
271:,
232:.
89:A
31:A
340:e
333:t
326:v
247:.
218:.
183:.
170:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
