ACTUALLY THE INVESTIGATION WAS RATHER LIMITED. THE SITE WAS INSPECTED VERY CLOSELY BUT THERE WASN'T MUCH OF THE AIRCRAFT TO LOOK AT. IT BECAME APPARENT QUITE EARLY THAT THE AIRCRAFT HAD ENTERED INTO MAST BUMPING, CAUSING THE MAIN ROTOR TO SEPARATE FROM THE AIRCRAFT. THIS WAS EVIDENCED BY THE MAST WHICH SHOWED TWO MARKS 180 DEGREES APART. ON ONE SIDE THE DENTS WERE LIGHT AND MODERATE. HOWEVER 180 FROM THAT POINT THE MAST WAS CAVED IN AND BROKEN. THE MAIN ROTOR OF THIS AIRCRAFT IS STILL MISSING. IT IS THE GENERAL CONSENSES OF THE BOARD THAT IT IS AT THE BOTTOM OF THE OCEAN. THE CRASH SITE IS ONLY 300-400 METERS FROM THE COAST AND THAT WAS THE FLIGHT LINE OF THE AIRCRAFT ON IMPACT. FROM WHAT WAS RECONSTRUCTED THROUGH WITNESS IT IS EXTREMELY DIFFICULT TO DETERMINE WHAT HAPPENED. THE NEAREST WITNESS WAS APPROX 2.5 MILES FROM THE SCENE. HOWEVER IT WAS DETERMINED THAT CPT MATHIS HAD THE AIRCRAFT OUT FIRING THE WEAPONS IN PREPARATION OF THE AIRCRAFT ENTERING ITS EIGHT P.E. ALTHOUGH THE WITNESS STATEMENTS ARE SKETCHY AND IN CONTRIDICTION WITH EACH OTHER, I FEEL IT IS SAFE TO SAY THAT ONE OF HIS GUNS RUNS CPT MATHIS EXPERIENCED A SCAS HARDOVER IN THE PITCH CHANNEL. THIS IS EVIDENCED BY THE STATEMENTS SAYING THE AIRCRAFT APPEARED TO "TUCK VIOLENTLY" AND SEEMED TO START TO RECOVER, THEN WENT OUT OF CONTROL AND FELL STRAIGHT DOWN. AFTER LOOKING AT THE WRECKAGE I KNOW THE MAIN ROTOR DEPARTED THE AIRCRAFT IN FLIGHT. AT THE SCENE THERE ARE NO SIGNS OF THE ROTOR AND WHEN THE MAST HIT THE GROUND IT FILLED WITH SAND. ALSO WHEN THE MAIN ROTOR LEFT THE AIRCRAFT IT IMPACTED THE TAIL ROTOR BLADES, TAKING ONE BLADE AND TEARING OFF THE GROSS HEAD AND PITCH CHANGE LINKS. THE 90 DEGREE GEAR BOX LEFT PRIOR TO IMPACT. FROM THE DIRECTION THE AIRCRAFT WAS DIVING IT YAWED TO THE LEFT AFTER LOSING ITS BLADES. THE AIRCRAFT IMPACTED ON ITS RIGHT SKID & SIDE. THERE WERE SIGNES OF ONLY 3-4 FEET OF FORWARD SKIDDING ON IMPACT THE AIRCRAFT WAS APPROXIMATELY 40 TO THE HEADING OF THE DIVE WAS ENTERED FROM. I BELIEVE THE AIRCRAFT ENTERED MAST BUMPING FROM ONE OR TWO THING OR POSSIBLY A COMBINATION OF BOTH. FIRST THE SCAS FAILURE OR HARD OVER AND SECOND, POSSIBLE OVER CORRECTION ON THE PILOTS PART CAUSING THE MAIN ROTOR TO FLEX DOWN AND IMPACT THE MAST. HOWEVER I MUST POINT OUT THAT NO CHECK OF THE SCAS COMPONENTS CAN BE MADE AS THEY WERE DESTROYED BY THE FIRE. UPON RESEARCH OF THE PAST 2408-13'S ON THIS AIRCRAFT NO EVIDENCE OF PAST SCAS PROBLEMS WERE FOUND. UNFORTUNATELY THE LOG BOOK WAS ALSO DESTROYED SO THE MOST RECENT 2408-13 AND THE 2408-14 CANNOT BE EXAMINED.\\
This record was last updated on 05/25/98
The following is crew member information for this incident:
The following is Goldbook
information on US Army helicopter AH-1G tail number 67-15671
It is provided here as an ESTIMATE of the history of this helicopter
and is not intended to be the final authority.
This helicopter was purchased by the US Army in 0768.
Please provide any additional information on this helicopter to the VHPA.
DATE FLT HRS UIC UNIT AREA POST COUNTRY 6807 0 0 W0MHAA DIR SUP / TRAN IN TRANSIT SHARPE AD AVCOM 6808 0 0 W0MHAA DIR SUP / TRAN IN MAINT SHARPE AD AVCOM 6809 0 0 W0MHAA DIR SUP / TRAN IN MAINT SHARPE AD AVCOM 6810 0 0 3300 HHD 44 ENG GP THAILAND PACIFIC 6811 0 0 WADPT0 UNIT NOT KNOWN VIETNAM RVN 6812 24 24 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6901 14 38 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6902 0 38 3205 HHD 44 ENG GP THAILAND PACIFIC 6903 0 38 3205 HHD 44 ENG GP THAILAND PACIFIC 6904 79 117 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6905 0 117 3205 HHD 44 ENG GP THAILAND PACIFIC 6906 0 117 3205 HHD 44 ENG GP THAILAND PACIFIC 6907 47 164 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6908 36 200 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6909 51 251 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6910 32 283 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6911 27 310 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 6912 27 337 WADPD0 D TRP 2SQ1CV4IN VIETNAM RVN 7001 54 391 WADPD0 D 2SQ 1 CAV VIETNAM RVN 7002 66 457 WADPD0 D TRP 211 CAV VIETNAM RVN
Please send additions or corrections to:
Gary Roush
43 Overbrook Road
Painted Post, NY 14870
Printed from databases on: 02/21/99
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