54:
27:
39:
413:
231:, and other various sites. Since 1991, there have been over 230 cases of aircraft damage and/or injury due to unsuccessful take-offs or landings in a dust environment. Although the majority of the incidents occur during landings, there have been a significant number of incidents occurring during take-offs as well. For the more than 50 brown-out incidents with damage reported to date during Army military operations in the 2001–2007 time frame, 80 percent were during landings and 20 percent during takeoffs.
239:
301:
367:(N502MT) — EMS helicopter crashed into terrain while maneuvering in reduced visibility at night while transporting a patient. The pilot, flight paramedic, patient, and patient's mother were killed, and the flight nurse was seriously injured. Witnesses reported brown-out conditions at the time of the accident.
287:
creates a high-velocity downwash, which stirs up the dust cloud from a much higher altitude. This can be a problem while hovering during personnel insertion and extraction via hoist or rope. Initial operational experience indicates that although the dust cloud is larger with the MV-22 than it is with
234:
Helicopter brownout is a US$ 100 million per year problem for the U.S. Military in
Afghanistan and Iraq. The Army cites brownout in three out of every four helicopter accidents there. Brownout accidents occur close to the ground and at low airspeed, giving these accidents a higher survivability than
258:, making it more susceptible to rollover if the pilot begins to lose roll attitude control from the brownout. But at night, the Apache's infra-red vision system provides improved visibility when dust obscures the moonlight — the Blackhawk's night vision goggles only amplify available visible light.
193:
illusion, where the helicopter appears to be turning when it is actually in a level hover. This can also cause the pilot to make incorrect control inputs, which can quickly lead to disaster when hovering near the ground. In night landings, aircraft lighting can enhance the visual illusions by
1463:
Right here on the flight line in crash landings, the helicopters landing in what are called brown-out conditions, meaning the dust on the desert floor rises up and engulfs the helicopter and it is very difficult for the pilot to see the ground in those conditions and very easy to mess up the
270:(POGO), 12 of 41 U.S. Army brownout accidents between 2002 and 2005 involved CH-47s. Data compiled by POGO from government sources show the Chinook flew 7 percent of all U.S. Army helicopter flight hours between 2003 and 2005 but accounted for 30 percent of all brownout-related accidents.
53:
444:
N — Helicopter inadvertently touched down on takeoff while drifting to the right and rolled over. One member of the crew was ejected, and the other three exited before the aircraft was destroyed by fire. Another nearby helicopter was damaged by flying debris from the
188:
for reference may instinctively try to level the aircraft with respect to the false horizon, resulting in an accident. Helicopter rotor wash also causes sand to blow around outside the cockpit windows, possibly leading the pilot to experience the
456:
G Pave Hawk — helicopter departed slowly and had insufficient power to climb out of the dust cloud generated on take-off from its own rotor wash. The pilot tried to land and hit a sand berm. The six aircraft occupants evacuated without serious
265:
has had a relatively high frequency of brownout accidents. As of 2007, nine
Chinooks were lost in action in Afghanistan, and at least two were caused by brownout, which likely played a role in several other incidents. According to the
73:) is an in-flight visibility restriction due to dust or sand in the air. In a brownout, the pilot cannot see nearby objects which provide the outside visual references necessary to control the aircraft near the ground. This can cause
531:(D-105) — helicopter made a "hard landing" due to "brown-out conditions" as the crew was attempting to insert forces on the border between Afghanistan and Pakistan. The aircraft was destroyed by fire but there were no injuries.
512:
Black Hawk — helicopter collided with a sling load during a pickup attempt in brownout conditions. The three injured crew members pulled the two seriously injured pilots from the burning wreckage before it was destroyed by
478:
D Apache — while departing from FOB Shell for a combat mission with approximately 40 other fully loaded helicopters, the helicopter rolled over in severe brownout approximately 4 minutes after the first aircraft took
841:
To counteract this, the EH101's 'winged-tip' rotor blades create what its pilots call the "donut effect" – a circular window of clear air inside the dust storm that allows them to see the ground as they come in to
403:(N500FU), helicopter was substantially damaged when the main rotor blade hit a tree on landing, with no injuries. Recent construction work at the site disturbed the surface, creating unexpected brownout conditions.
174:
Non-visual displays of position and orientation data derived from suitable sensors, such as
Tactile Situational Awareness Systems (TSAS) providing information to the pilot through the sense of touch using
1081:
Data compiled by POGO from government sources show the
Chinook flew 7 percent of all U.S. Army helicopter flight hours between 2003 and 2005 but accounted for 30 percent of all brownout-related accidents.
333:
after an aborted takeoff at a remote location, with no injuries. The helicopter was substantially damaged. Pilot experienced brownout after lifting off approximately 3 feet (0.91 meters) off the ground.
486:
D Apache (97-5032) — after returning to FOB Shell from a combat mission, the helicopter landed hard in brownout conditions, rolled over, and was severely damaged (though later salvaged and repaired).
433:
helicopter approached to land at night, it caused a brownout, obscuring the landing area. The aircraft crashed into a sand dune, killing two rangers on board as passengers, and injuring three others.
382:) — MEDEVAC helicopter landed hard on a baseball field in a brownout, damaging the tail boom, but without injuring the crew. The damage was not discovered on a post-flight inspection, or subsequent
808:
The replaces the standard horizontal situation indicator and shows the crew digital ground velocity, analog vertical velocity, digital and analog radar altimeter, and analog heading symbology.
471:
March 23, 2003, U.S. Army
Aviation Base Camp, Central Iraq — U.S. Army 6th Cavalry Regiment, AH-64D Apache Longbow — helicopter crashed on takeoff on the unit's first day at that base camp.
1072:
1143:
254:
in the first three weeks of the 2003 Iraq invasion, while only one had been lost in combat in the same time period. The tandem seat Apache has a narrower stance than the
1044:
1599:
343:
1154:
V-22 downdraft is so strong...that it can create "brownout" conditions...as a result, when rope ladders are used, the V-22 must hover at higher altitudes...
602:
501:
821:
116:
due to sloped and uneven terrain. Brownouts have claimed more helicopters in recent military operations than all other threats combined (as of 2005).
26:
468:
M (s/n 10930) — helicopter was badly damaged when crew misjudged a night landing in brownout conditions. Some minor injuries. Aircraft was salvaged.
416:
An AH-64A Apache from the 2nd
Squadron, 6th Cavalry Regiment, leaves an enormous cloud of dust after landing at a desert airstrip in central Iraq.
350:
BA (N911NT) — helicopter was destroyed after colliding with trees in an aborted landing at a ballpark killing the pilot and injuring one of two
770:
541:
1076:
738:
705:
937:
1538:
235:
other types. However, there have been deaths in military accidents in Iraq and
Afghanistan, and nearly all of those were preventable.
709:
882:
855:
1097:
292:
it is replacing, pilots report regaining visibility near the ground, allowing them to use visual references prior to landing.
1054:
1267:
1242:
1217:
1192:
655:
577:
1524:
1321:
1093:
1485:
1432:
1393:
1347:
The search-and-rescue Black Hawk helicopter crashed into a sand dune near the perimeter of the airfield in
Dalbandin.
1297:
792:
38:
1594:
112:
during near-ground flight causes significant flight safety risks from aircraft and ground obstacle collisions, and
198:
609:
387:
267:
224:
1022:
987:
159:
1027:
205:
829:
354:
on board. Witnesses on the scene reported a brownout cloud obscured their vision of the accident sequence.
1452:
215:
Several coalition military aircraft were lost due to roll-overs while executing dust landings during the
684:
1068:
449:
220:
758:
Brownouts have claimed more helicopters in recent military operations than all other threats combined.
426:
20:
1128:
969:
Sabbagh, Leslie (2006-10-03). "Flying Blind in Iraq: U.S. Helicopters
Navigate Real Desert Storms".
640:
1360:
1589:
863:
603:"Analysis of Army Helicopter Pilot Error Mishap Data and The Implications For Handling Qualities"
1568:
1335:
915:
778:
746:
656:"AFOSR News – National Helicopter Experts Gather to Discuss Aerodynamic Solutions for Brownout"
437:
74:
46:
1569:
Michael Yon - Online
Magazine - The Kopp-Etchells Effect - CH-47 Night Landings in Afghanistan
713:
693:
Pilots have compared landing during brownouts to parallel parking a car with your eyes closed.
589:
Brown-out conditions connote in-flight visibility restrictions due to dust or sand in the air.
223:, the U.S. Army recorded over 40 cases of brownout condition accidents during training at the
1573:
1115:
627:
520:— Hard landing during brownout. Rotor blades struck terrain, but helicopter remained upright.
461:
383:
78:
1516:
1313:
952:
251:
1542:
1263:
1238:
1213:
1188:
890:
169:
8:
1049:
1148:
998:
948:
568:
318:
185:
184:
Blowing sand and dust can cause an illusion of a tilted horizon. A pilot not using the
1168:"Interview - Major Rob Freeland, VMMT-204 - Former Operations Officer and CH-46 pilot"
1045:"Nobody's First Choice : Another Air Force deal that doesn't pass the smell test"
902:"Pixie dust" is a strange phenomenon often encountered during night brownout landings.
659:
1502:
1481:
1428:
1293:
971:
867:
430:
339:
42:
1104:
497:
escort mission, resulting in main rotor strike, rollover, and loss of the aircraft.
412:
371:
330:
255:
152:
113:
106:
82:
938:"Owning the Aviation Edge : NVGPID: A Simple Device to Train Crucial Skills"
396:
119:
There are several factors which affect the probability and severity of brownout:
246:
is not visible in the large brownout dust cloud that it created during training.
546:
351:
31:
238:
1583:
528:
262:
58:
280:
aircraft, which was deployed for combat in Iraq in September 2007. The high
360:
305:
284:
243:
165:
124:
1397:
796:
101:
landing and take-off operations in arid desert terrain. Intense, blinding
1167:
524:
274:
81:
leading to an accident. Pilots have compared landing during brownouts to
400:
228:
102:
98:
86:
570:
Special Investigation Report on Emergency Medical Services Operations
516:
April 26, 2004, location not specified — U.S. Marine Corps, HMM-266,
422:
281:
277:
1503:"Corrosion repairs using the radial bristle disc.(Air Wing Toolbox)"
1425:
Ah-64 Apache Units of Operations Enduring Freedom and Iraqi Freedom
1092:
658:. The Air Force Office of Scientific Research, AFRL. Archived from
364:
216:
109:
300:
1539:"Touchdown Aviation - Royal Netherlands Air Force - 298 Squadron"
494:
326:
190:
988:"Situational Awareness and Spatial Disorientation in the Fight"
822:"Super Chopper : Life-Saving Features: No More Brown-Outs"
517:
505:
142:
Countermeasures to prevent brownout-related accidents include:
793:"Vertiflight Breaking News : Army Prepares Brownout Kit"
509:
490:
483:
475:
465:
464:, Kuwait — U.S. Air Force, 20th Special Operations Squadron,
453:
375:
347:
322:
289:
1554:
D-105 was lost on the 27th of July and replaced by the D-104
685:"U.S. helicopter crash-lands in Iraq, injuring pilots, crew"
441:
489:
March 31, 2003, Iraq — U.S. Army 103rd Aviation Regiment,
482:
March 28, 2003, Iraq — U.S. Army 101st Aviation Regiment,
474:
March 28, 2003, Iraq — U.S. Army 101st Aviation Regiment,
1457:
1336:"Dalbandin, Pakistan : 28°52'41.15"N 64°24'12.54"E"
1318:
wo Soldiers Killed; Special Forces Assault Taliban Sites
527:
Afghanistan — Royal Netherlands Air Force, 298 Squadron
1517:"Officials Report on Chinook Incidents in Afghanistan"
1367:. Vol. 86, no. 6. Naval Aviation. p. 4.
1314:"Officials Report on Chinook Incidents in Afghanistan"
1067:
250:
Brownout accidents destroyed or severely damaged four
493:
D Apache (99-5104) creates brownout on takeoff for a
1378:
Chapman, Suzann (February 2003). "Aerospace World".
907:
777:. Motor-Presse Stuttgart. 2007-03-18. Archived from
295:
219:period of 1990–91. In the decade between then and
1427:. Oxford: Osprey Publishing (UK). pp. 53–54.
1290:Shadow Warriors: a History of the Us Army Rangers
924:Sometimes the halos appear like distant galaxies.
440:(FOB), Afghanistan — U.S. Marine Corps, HMM-365,
1581:
1144:"Combat, With Limits, Looms for Hybrid Aircraft"
425:, Pakistan — U.S. Army Rangers, Task Force 3/75
97:The brownout phenomenon causes accidents during
1500:
201:have been extensively observed in Afghanistan.
1165:
795:. AHS International. July 2004. Archived from
321:, USA — Rocky Mountain Holdings, Aerospatiale
273:Brownout is a particular concern for the U.S.
1600:Accidents and incidents involving helicopters
935:
828:. National Geographic Channel. Archived from
1418:
1416:
1414:
653:
542:Safety of emergency medical services flights
61:kicks up a dust cloud resulting in brownout.
1446:
1444:
1358:
1292:. Reading: Osprey Publishing. p. 184.
210:
49:on exercise in the Jordanian desert in 2013
889:. Access Intelligence, LLC. Archived from
856:"Desert sandstorms add dangers for pilots"
745:. Access Intelligence, LLC. Archived from
706:"STO: Solicitations - Sandblaster Program"
1475:
1422:
1411:
1287:
1073:"Rescue Helicopter has Brownout Problems"
1016:
1014:
979:
710:Defense Advanced Research Projects Agency
563:
561:
1450:
1441:
1098:"V-22 Program Status Report to Congress"
1042:
411:
299:
237:
155:systems also known as "see and remember"
52:
37:
25:
1453:"On the Scene : First deep attack"
1377:
1023:"Desert landings rattle pilots' nerves"
968:
853:
732:
730:
678:
676:
1582:
1020:
1011:
874:
819:
558:
374:, USA — Native American Air Ambulance
1141:
985:
880:
736:
682:
508:— U.S. Army 101st Aviation Regiment,
452:— U.S. Air Force, 347th Rescue Wing,
304:N502MT EMS helicopter wreckage, near
16:In-flight visual impairment by pilots
1268:National Transportation Safety Board
1243:National Transportation Safety Board
1218:National Transportation Safety Board
1193:National Transportation Safety Board
881:Colby, Lt. Col. Steve (2005-07-01).
737:Colby, Lt. Col. Steve (2005-03-01).
727:
673:
647:
578:National Transportation Safety Board
179:
1525:United States Department of Defense
1322:United States Department of Defense
1094:United States Department of Defense
913:
854:Lessard, Dr. Charles (2003-04-09).
600:
34:gets a brownout on a dirt airstrip.
13:
1480:. New York: Praeger. p. 255.
986:Curry, LTC Ian P. (January 2006).
683:Skiba, Katherine M. (2003-04-07).
168:such as the "winged rotor" on the
14:
1611:
1562:
1264:"NTSB Accident Brief: SEA05CA173"
1239:"NTSB Accident Brief: LAX04LA285"
1214:"NTSB Accident Brief: LAX01LA304"
1189:"NTSB Accident Brief: LAX01LA283"
813:
296:Partial list of related accidents
194:illuminating the brownout cloud.
1043:Goldfarb, Michael (2007-04-19).
1531:
1509:
1494:
1469:
1386:
1371:
1352:
1328:
1306:
1281:
1256:
1231:
1206:
1181:
1159:
1135:
1086:
1061:
1036:
962:
929:
847:
771:"News in Brief / Kurzmeldungen"
388:aircraft maintenance technician
268:Project on Government Oversight
225:Fort Irwin Military Reservation
1501:Doughty, Thomas (2004-06-22).
1361:"Brownout.(Grampaw Pettibone)"
785:
763:
698:
594:
160:horizontal situation indicator
92:
1:
1521:American Forces Press Service
1451:Chilcote, Ryan (2003-03-29).
1170:. Dash 2 Aviation Photography
1166:Llinares, Rick (2006-11-11).
820:Harvey, Gareth (2005-11-28).
552:
386:, and was only noticed by an
206:Sensory Illusions in Aviation
1423:Bernstein, Jonathan (2005).
1396:. 2007-06-01. Archived from
1142:Wayne, Leslie (2007-04-14).
1021:Liewer, Steve (2003-04-14).
951:. p. 22. Archived from
936:Gant, Randall (April 2007).
601:Key, David L. (1999-09-14).
547:Hazards of helicopter flight
227:National Training Center in
197:The visible effects of sand
7:
1476:Cordesman, Anthony (2003).
914:Yon, Michael (2009-08-17).
654:Stein, Vicki (2007-02-12).
580:. June 2001. NTSB/SIR-06/01
535:
407:
311:
10:
1616:
1394:"1968 USAF Serial Numbers"
1359:Wilbur, Ted (2004-09-01).
1069:United Press International
689:Milwaukee Journal Sentinel
450:Operation Enduring Freedom
221:Operation Enduring Freedom
203:
18:
860:Texas A&M Engineering
21:Brownout (disambiguation)
864:Texas A&M University
460:February 13, 2003, near
211:U.S. military experience
138:approach speed and angle
89:with one's eyes closed.
1595:Helicopter aerodynamics
1288:Bahmanyar, Mir (2006).
162:with improved symbology
1123:Cite journal requires
1057:on September 27, 2007.
922:. Michael Yon Online.
916:"Kopp-Etchells Effect"
635:Cite journal requires
448:August 12, 2002, FOB,
438:Forward operating base
429:K Black Hawk — As the
417:
399:, USA, Heliflite LLC,
384:pre-flight inspections
329:helicopter damaged in
308:
252:AH-64D Apache Longbows
247:
75:spatial disorientation
62:
50:
35:
462:Ali Al Salem Air Base
415:
303:
241:
204:Further information:
79:situational awareness
56:
41:
29:
1338:. Globalsecurity.org
826:Engineering Archives
775:Flug Revue (Germany)
344:Enloe Medical Center
338:September 22, 2001,
170:AgustaWestland EH101
19:For other uses, see
1576:(Vertical Magazine)
1365:Naval Aviation News
1050:The Weekly Standard
129:rotor configuration
1574:Battling Brownouts
1458:Cable News Network
1380:AIR FORCE Magazine
1149:The New York Times
1030:, European edition
999:United States Army
949:United States Army
920:Michael Yon Online
436:December 6, 2001,
421:October 19, 2001,
418:
363:, USA — Med-Trans
319:Vinton, California
309:
248:
186:flight instruments
105:stirred up by the
63:
51:
36:
1028:Stars and Stripes
972:Popular Mechanics
576:. PB2006-917001.
502:Camp Thunder Road
431:search and rescue
395:August 16, 2005,
340:Chico, California
317:August 18, 2001,
180:Sensory illusions
1607:
1557:
1556:
1551:
1550:
1541:. Archived from
1535:
1529:
1528:
1513:
1507:
1506:
1498:
1492:
1491:
1473:
1467:
1466:
1448:
1439:
1438:
1420:
1409:
1408:
1406:
1405:
1390:
1384:
1383:
1375:
1369:
1368:
1356:
1350:
1349:
1344:
1343:
1332:
1326:
1325:
1310:
1304:
1303:
1285:
1279:
1278:
1276:
1275:
1260:
1254:
1253:
1251:
1250:
1235:
1229:
1228:
1226:
1225:
1210:
1204:
1203:
1201:
1200:
1185:
1179:
1178:
1176:
1175:
1163:
1157:
1156:
1139:
1133:
1132:
1126:
1121:
1119:
1111:
1109:
1103:. Archived from
1102:
1090:
1084:
1083:
1075:. Archived from
1065:
1059:
1058:
1053:. Archived from
1040:
1034:
1033:
1018:
1009:
1008:
1006:
1005:
992:
983:
977:
976:
966:
960:
959:
957:
942:
933:
927:
926:
911:
905:
904:
899:
898:
887:Rotor & Wing
878:
872:
871:
866:. Archived from
851:
845:
844:
838:
837:
817:
811:
810:
805:
804:
789:
783:
782:
767:
761:
760:
755:
754:
743:Rotor & Wing
734:
725:
724:
722:
721:
712:. Archived from
702:
696:
695:
680:
671:
670:
668:
667:
651:
645:
644:
638:
633:
631:
623:
621:
620:
614:
608:. Archived from
607:
598:
592:
591:
586:
585:
575:
565:
372:Cibecue, Arizona
359:March 21, 2004,
331:dynamic rollover
256:UH-60 Black Hawk
153:Synthetic vision
146:Site preparation
132:soil composition
114:dynamic rollover
107:helicopter rotor
83:parallel parking
57:Downwash from a
1615:
1614:
1610:
1609:
1608:
1606:
1605:
1604:
1580:
1579:
1565:
1560:
1548:
1546:
1537:
1536:
1532:
1515:
1514:
1510:
1499:
1495:
1488:
1474:
1470:
1449:
1442:
1435:
1421:
1412:
1403:
1401:
1392:
1391:
1387:
1376:
1372:
1357:
1353:
1341:
1339:
1334:
1333:
1329:
1312:
1311:
1307:
1300:
1286:
1282:
1273:
1271:
1262:
1261:
1257:
1248:
1246:
1237:
1236:
1232:
1223:
1221:
1212:
1211:
1207:
1198:
1196:
1187:
1186:
1182:
1173:
1171:
1164:
1160:
1140:
1136:
1124:
1122:
1113:
1112:
1107:
1100:
1091:
1087:
1079:on 2007-09-06.
1066:
1062:
1041:
1037:
1019:
1012:
1003:
1001:
990:
984:
980:
967:
963:
955:
940:
934:
930:
912:
908:
896:
894:
883:"Military Spin"
879:
875:
852:
848:
835:
833:
818:
814:
802:
800:
791:
790:
786:
769:
768:
764:
752:
750:
739:"Military Spin"
735:
728:
719:
717:
704:
703:
699:
681:
674:
665:
663:
652:
648:
636:
634:
625:
624:
618:
616:
612:
605:
599:
595:
583:
581:
573:
567:
566:
559:
555:
538:
523:July 27, 2005,
500:April 5, 2003,
410:
397:Donnelly, Idaho
370:June 26, 2004,
314:
298:
213:
208:
182:
149:Pilot technique
95:
65:In aviation, a
32:HC-130 Hercules
24:
17:
12:
11:
5:
1613:
1603:
1602:
1597:
1592:
1590:Aviation risks
1578:
1577:
1571:
1564:
1563:External links
1561:
1559:
1558:
1530:
1508:
1493:
1486:
1468:
1440:
1433:
1410:
1385:
1370:
1351:
1327:
1305:
1298:
1280:
1255:
1230:
1205:
1180:
1158:
1134:
1125:|journal=
1110:on 2007-09-28.
1096:(April 2002).
1085:
1060:
1035:
1010:
978:
961:
958:on 2007-09-27.
928:
906:
873:
870:on 2008-05-11.
846:
812:
784:
781:on 2007-07-07.
762:
726:
697:
672:
646:
637:|journal=
593:
556:
554:
551:
550:
549:
544:
537:
534:
533:
532:
529:CH-47D Chinook
521:
514:
498:
487:
480:
472:
469:
458:
446:
434:
409:
406:
405:
404:
392:
391:
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361:Pyote, Texas
306:Pyote, Texas
285:disk loading
272:
260:
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244:MV-22 Osprey
233:
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166:Aerodynamics
141:
125:disk loading
118:
96:
77:and loss of
70:
66:
64:
525:Spin Buldak
401:Hughes 369E
275:V-22 Osprey
103:dust clouds
93:Description
1584:Categories
1549:2007-06-24
1404:2007-06-25
1342:2007-06-28
1274:2007-06-26
1249:2007-06-26
1224:2007-06-26
1199:2007-06-26
1174:2007-06-23
1004:2007-06-23
897:2007-06-25
836:2009-08-01
803:2007-06-28
753:2007-06-25
720:2007-06-24
666:2007-06-25
619:2007-06-23
584:2007-06-26
553:References
229:California
99:helicopter
87:automobile
995:FLIGHTfax
423:Dalbandin
342:, USA —
282:proprotor
278:tiltrotor
158:Upgraded
71:brown-out
1464:landing.
536:See also
408:Military
365:Bell 407
312:Civilian
217:Gulf War
175:tactors.
110:downwash
67:brownout
43:Sea King
495:MEDEVAC
457:injury.
327:MEDEVAC
191:vection
47:845 NAS
1484:
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518:CH-46E
506:Kuwait
445:rotor.
380:N5226R
123:rotor
1108:(PDF)
1101:(PDF)
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956:(PDF)
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842:land.
613:(PDF)
606:(PDF)
574:(PDF)
513:fire.
510:UH-60
491:AH-64
484:AH-64
476:AH-64
466:MH-53
454:HH-60
427:MH-60
376:AS350
348:AS350
323:AS355
290:CH-46
1482:ISBN
1429:ISBN
1294:ISBN
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641:help
479:off.
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