31:
1656:
165:
from 1981 to 2010, when mechanical problems took it out of service. It was retired in
January 2020 due to its poor mechanical condition and subsequently donated to the Railroading Heritage of Midwest America, where it is now undergoing a second restoration. The second example,
739:
747:
1635:
1630:
1693:
300:
269:
809:
443:
378:
177:
Though originally intended for freight service, many units could be found for leading passenger consists as well. Railroads that used the
688:
645:
1717:
670:
1686:
359:
1142:
772:
277:
260:
241:
222:
1152:
802:
740:"Railroading Heritage of Midwest America, Union Pacific agree to donation of Challenger, other locomotives, cars"
461:
Identical to NP Z-6 class; 903–904 sold to GN January 1940; purchased back March 1950 and July 1946 respectively
1679:
1135:
607:
584:
565:
546:
527:
508:
489:
386:
312:
143:
1712:
157:
Today, the only
Challenger locomotives that survive were both owned by Union Pacific. One such locomotive,
1531:
1463:
1334:
1223:
483:
171:
139:
132:
106:
93:
1625:
1611:
602:
These and the 15 units for the D&RGW were the only ones of this type made by
Baldwin. Scrapped 1958
147:
98:
787:
1521:
1514:
1509:
1502:
1497:
1492:
1471:
795:
381:
903–904; sold back to SP&S March 1950 and July 1946 respectively. Scrapped between 1953 and 1957
210:
114:
30:
1606:
1535:
1467:
1236:
1227:
937:
167:
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85:
73:
1655:
712:
1601:
1588:
1338:
1157:
1663:
1231:
50:
1596:
354:
Diverted to the D&RGW from a UP order. To
Clinchfield Railroad in 1947. Scrapped 1959
162:
818:
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39:
20:
1706:
58:
54:
24:
1324:
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777:
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1453:
782:
892:
1181:
47:
34:
Union
Pacific Challenger No. 3985 is an example of a 4-6-6-4 locomotive.
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142:, but many other railroads ordered them as well. An expansion for the
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791:
713:"Railroading Heritage of Midwest America - official website"
783:
Web Site of ToyTrains1 4-6-6-4 Challenger Steam
Locomotives
646:"Union Pacific 4-6-6-4 "Challenger" Locomotives in the USA"
76:, on which both engine units swivel, but is referred to as
42:
for classifying steam locomotives by wheel arrangement, a
715:. Railroading Heritage of Midwest America. Archived from
1667:
716:
819:
Steam locomotive wheel arrangements (Whyte notation)
1587:
1530:
1462:
1333:
1222:
1151:
825:
689:"Work begins on Union Pacific Challenger No. 3985"
503:To UP 3800–3814. Scrapped between 1957 and 1958
161:, was operated by the Union Pacific Railroad in
1687:
803:
8:
1662:This steam locomotive-related article is a
1694:
1680:
810:
796:
788:
92:(also known as German classification and
19:"4664" redirects here. For the year, see
183:
29:
16:Articulated locomotive wheel arrangement
637:
72:A similar wheel arrangement exists for
301:Denver and Rio Grande Western Railroad
738:Glischinski, Steve (April 28, 2022).
444:Spokane, Portland and Seattle Railway
83:Other equivalent classifications are:
7:
1652:
1650:
138:Challengers were most common in the
57:followed by two sets of six coupled
778:The Union Pacific Challenger Roster
1666:. You can help Knowledge (XXG) by
170:is on static display in Cody Park
65:. 4-6-6-4's are commonly known as
14:
560:No. 3977 and 3985 are preserved.
1654:
746:. Kalmbach Media. Archived from
625:Scrapped between 1953 and 1959
579:Scrapped between 1957 and 1959
541:Scrapped between 1958 and 1959
522:To UP 3815–3839. Scrapped 1958
438:Scrapped between 1952 and 1957
421:Scrapped between 1951 and 1954
404:Scrapped between 1950 and 1953
337:Scrapped between 1951 and 1956
320:Scrapped between 1951 and 1956
295:Scrapped between 1951 and 1959
272:, acquired 1947. Scrapped 1959
249:Scrapped between 1955 and 1959
230:Scrapped between 1953 and 1958
773:The Challenger Type Locomotive
1:
671:"The Challenger at high tide"
185:4-6-6-4 construction roster
278:Delaware and Hudson Railway
1734:
1649:
478:Identical to NP Z-8 class
18:
1620:
482:
442:
385:
299:
209:
181:type locomotive include:
608:Western Pacific Railroad
585:Western Maryland Railway
387:Northern Pacific Railway
154:, instead of a 4-6-6-4.
144:Union Pacific Challenger
1532:Articulated locomotives
1522:2-4-4-2+2-8-8-2+2-4-4-2
1464:Articulated locomotives
1335:Articulated locomotives
1224:Articulated locomotives
650:www.steamlocomotive.com
133:articulated locomotives
1718:Steam locomotive stubs
1624:Other notation forms:
484:Union Pacific Railroad
360:Great Northern Railway
213:(12 new, 6 secondhand)
172:North Platte, Nebraska
140:Union Pacific Railroad
107:Turkish classification
94:Italian classification
35:
23:. For the number, see
1498:0-6-2+2-4-2-4-2+2-6-0
148:Union Pacific Big Boy
99:French classification
33:
211:Clinchfield Railroad
115:Swiss classification
826:Single engine types
190:Railroad (quantity)
186:
74:Garratt locomotives
1589:Geared locomotives
1515:2-10-10-10-10-10-2
184:
168:Union Pacific 3977
159:Union Pacific 3985
125:UIC classification
86:UIC classification
36:
1675:
1674:
1644:
1643:
750:on April 28, 2022
719:on April 28, 2022
629:
628:
163:excursion service
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51:steam locomotive
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63:trailing wheels
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1713:Whyte notation
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767:External links
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675:Classic Trains
669:Keefe, Kevin.
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362:(2 secondhand)
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146:class was the
127:is refined to
59:driving wheels
55:leading wheels
53:that has four
40:Whyte notation
21:5th millennium
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1510:2-8-8-8-8-8-2
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1153:Divided drive
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45:
41:
32:
26:
25:4000 (number)
22:
1668:expanding it
1661:
1646:
1409:
1160:engine types
752:. Retrieved
748:the original
743:
733:
721:. Retrieved
717:the original
707:
696:. Retrieved
692:
683:
674:
664:
653:. Retrieved
649:
640:
196:Road numbers
178:
176:
156:
137:
128:
122:
118:
110:
102:
89:
82:
71:
66:
43:
37:
1493:2-8-8-8-8-2
1325:4-8-4+4-8-4
1320:4-8-2+2-8-4
1315:4-8-0+0-8-4
1310:2-8-2+2-8-2
1305:2-8-0+0-8-2
1298:4-6-4+4-6-4
1293:4-6-2+2-6-4
1288:4-6-0+0-6-4
1283:2-6-2+2-6-2
1278:2-6-0+0-6-2
1273:0-6-2+2-6-0
1268:0-6-0+0-6-0
1261:4-4-2+2-4-4
1256:2-4-2+2-4-2
1251:2-4-0+0-4-2
1246:0-4-0+0-4-0
131:for simple
78:4-6-0+0-6-4
67:Challengers
1707:Categories
1612:Willamette
1470:and other
882:(monorail)
698:2023-01-07
655:2019-05-08
632:References
202:Build year
179:Challenger
1486:2-8-8-8-4
1481:2-8-8-8-2
1472:Multiplex
1454:2-10-10-2
599:1940–1941
593:1201–1212
570:3930–3949
551:3975–3999
532:3950–3969
513:3915–3939
494:3900–3914
435:1943–1944
429:5130–5149
412:5121–5126
401:1936–1937
395:5100–5120
368:4000–4001
345:3800–3805
328:3710–3714
309:3700–3709
292:1940–1946
286:1500–1539
270:D&RGW
227:1942–1943
61:and four
1182:2-2-4-0T
754:June 12,
723:June 12,
379:SP&S
129:(2'C)C2'
48:railroad
1607:Heisler
1567:0-6-4-0
1536:Engerth
1468:Triplex
1447:4-8-8-4
1442:4-8-8-2
1437:2-8-8-4
1432:2-8-8-2
1427:2-8-8-0
1422:0-8-8-0
1417:0-8-6-0
1410:4-6-6-4
1405:4-6-6-2
1400:4-4-6-2
1395:2-6-8-0
1390:2-6-6-6
1385:2-6-6-4
1380:2-6-6-2
1375:2-6-6-0
1370:0-6-6-0
1363:2-4-4-2
1358:2-4-4-0
1353:0-4-4-2
1348:0-4-4-0
1237:Garratt
1228:Fairlie
1214:4-6-4-4
1209:4-4-6-4
1204:6-4-4-6
1199:4-4-4-4
1194:2-4-6-2
1187:4-2-2-0
1177:2-2-2-2
1172:2-2-2-0
1167:0-2-2-0
893:0-4-0+4
616:401–407
596:Baldwin
469:910–911
452:900–905
331:Baldwin
313:Baldwin
257:670–675
238:660–663
219:650–657
199:Builder
152:4-8-8-4
119:3/5+3/5
103:230+032
44:4-6-6-4
38:In the
1602:Climax
1339:Mallet
1158:Duplex
1143:4-14-4
1136:4-12-2
1131:2-12-4
1126:2-12-2
1121:2-12-0
1116:0-12-0
1109:4-10-2
1104:4-10-0
1099:2-10-4
1094:2-10-2
1089:2-10-0
1084:0-10-2
1079:0-10-0
1022:0-8-4T
990:2-6-6T
970:0-6-6T
928:2-4-6T
923:2-4-4T
908:0-4-6T
903:0-4-4T
868:4-2-4T
853:2-2-4T
744:Trains
693:Trains
566:4664-5
547:4664-4
528:4664-3
205:Notes
1631:Swiss
1579:0-8-6
1574:0-8-4
1562:0-6-4
1557:2-6-4
1550:0-4-6
1545:0-4-4
1538:types
1474:types
1341:types
1239:types
1232:Meyer
1072:6-8-6
1067:4-8-6
1062:4-8-4
1057:4-8-2
1052:4-8-0
1047:2-8-6
1042:2-8-4
1037:2-8-2
1032:2-8-0
1027:0-8-6
1017:0-8-2
1012:0-8-0
1005:4-6-4
1000:4-6-2
995:4-6-0
985:2-6-4
980:2-6-2
975:2-6-0
965:0-6-4
960:0-6-2
955:0-6-0
948:4-4-6
943:4-4-4
938:4-4-2
933:4-4-0
918:2-4-2
913:2-4-0
898:0-4-2
888:0-4-0
880:0-3-0
873:6-2-0
863:4-2-2
858:4-2-0
848:2-2-2
843:2-2-0
838:0-2-4
833:0-2-2
613:M-100
509:CSA-2
490:CSA-1
486:(105)
325:L-105
317:1938
306:L-105
193:Class
111:35+35
46:is a
1664:stub
1597:Shay
1235:and
1155:and
756:2022
725:2022
622:1938
619:ALCO
587:(12)
576:1944
573:ALCO
557:1943
554:ALCO
538:1942
535:ALCO
519:1937
516:ALCO
500:1936
497:ALCO
475:1944
472:ALCO
458:1937
455:ALCO
432:ALCO
418:1941
415:ALCO
398:ALCO
389:(47)
374:1937
371:ALCO
351:1943
348:ALCO
342:L-97
334:1942
303:(21)
289:ALCO
280:(40)
265:1943
261:ALCO
246:1947
242:ALCO
223:ALCO
123:The
90:2CC2
1636:UIC
1626:AAR
610:(7)
590:M-2
466:Z-8
449:Z-6
446:(8)
426:Z-8
409:Z-7
392:Z-6
377:Ex-
365:Z-6
268:Ex-
254:E-3
235:E-2
216:E-1
1709::
1230:,
742:.
691:.
673:.
648:.
174:.
135:.
117::
109::
101::
88::
80:.
69:.
1695:e
1688:t
1681:v
1670:.
811:e
804:t
797:v
758:.
727:.
701:.
677:.
658:.
283:J
96:)
27:.
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