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ASN Wikibase Occurrence # 180376
Last updated: 20 November 2017
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Date:17-MAR-1972
Time:
Type:Silhouette image of generic UH1 model; specific model in this crash may look slightly different
Bell UH-1H Iroquois
Owner/operator:United States Army Aviation
Registration: 66-17051
C/n / msn:
Fatalities:Fatalities: 11 / Occupants: 11
Other fatalities:0
Airplane damage: Written off (damaged beyond repair)
Location:Saigon, SVN -   Vietnam
Phase:
Nature:Military
Departure airport:
Destination airport:
Narrative:
^2LT JAMES C. WILLIAMSON,^ AIRCRAFT COMMANDER, AND ^1LT DONEL J. DOBBS,^ BOTH UH-1 PILOTS, DEPARTED ^LASSITER HELICOPTER^ AT ^1030 HRS 17 MAR 72,^ ON AN AUTHORIZED MISSION IN WHICH TROOPS WERE TO BE INSERTED. THEIR AIRCRAFT WAS NUMBER 2 IN A THREE SHIP FORMATION. THE CREW CHIEF WAS ^SP4 RICHARD A. CROACKER,^ AND THE GUNNER WAS ^SP4 JOHN J. MOYNAHAN^. THE 3RD AIRCRAFT IN THE TRAIL FORMATION WAS LATE IN TAKING OFF AND WAS THEREFORE SOME DISTANCE BEHIND THE FORMATION AT ^1035 HRS^ WHEN THE ACCIDENT SEQUENCE BEGAN. WITNESSES STATE THAT THE FORMATION WAS JUST CLIMBING THROUGH 1500 FT. MSL, WHEN AIRCRAFT ^66-17051^ ENTERED A SLIGHT PITCH-UP ATTITUDE THEN ROLLED FORWARD INTO AN EXTREMELY NOSE LOW DIVE TERMINATING IN THE ^DONG NAI^ RIVER. THE ENTIRE CRASH SEQUENCE STARTED WITH A RADIO CALL BY ONE OF THE PILOTS (UNDETERMINED WHO OR WHAT RADIO), "MAYDAY, MAYDAY, MAYDAY" SIMULTANEOUSLY, THE AIRCRAFT PITCHED-UP THEN ROLLED FORWARD WITH THE NOSE IN VERY LOW ATTITUDE AND THE AIRCRAFT IN A DIVE. PRIOR TO OR NEAR THE BIG TREE IN THE FLIGHT PATH THE AIRCRAFT EXPERIENCED VIOLENT MAST BUMPING CAUSING THE MAIN ROTOR TO BREAK ITS DRIVE SHAFT AND SEPARATE. AT OR NEAR THIS POINT ON THE FLIGHT PATH THE ROTOR BLADE SLICED THROUGH THE COCKPIT AND FUSELAGE AREA AT LEAST TWO TIMES AND POSSIBLY MORE CUASING MASSIVE AMOUNTS OF IN-FLIGHT DISINTEGRATION. THE MAIN ROTOR TRAVELED, GENERALLY, FROM THE AREA ABOVE THE BIG TREE TO ITS RESTING PLACE IN THE SHALLOW WATER BY THE RIVER BANK. THE MAIN BODY OF THE AIRCRAFT CONTINUED IN A STEEP DIVE FROM THE AREA ABOVE THE BIG TREE TO ITS IMPACT IN THE ^DONG NAI^ RIVER LOSING ITS VERTICAL FIN JUST AT IMPACT. THE VERTICAL FIN HAD BEEN SEVERED PARTIALLY BY THE TAIL ROTOR AT ABOUT THE TIME OF MAIN ROTOR SEPARATION AND THE IMPACT COMPLETED ITS REMOVAL. UPON IMPACT, THE FUEL CELLS BURST OPEN AND THERE WAS A FLASH TYPE FIRE ON THE SURFACE OF THE WATER PROBABLY CAUSED BY THE BURNING OF THE JP-4. THE AIRCRAFT DISAPPEARED BENEATH THE SURFACE OF THE WATER IN 5-10 SECONDS AND CAME TO REST IN 35 FT. OF WATER.

Sources:

http://www.vhpa.org/KIA/incident/720317041ACD.HTM


Revision history:

Date/timeContributorUpdates
14-Oct-2015 15:55 TB Added
23-Jul-2016 09:05 68.66.98.6 Updated [Source, Narrative]
23-Jul-2016 09:06 harro Updated [Aircraft type, Registration, Source, Narrative]

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