ABBREVIATED AVIATION ACCIDENT REPORT (AAAR)
Source FINAL
1. Case Number 1a. Date of Accident 1b. Time 1c. Aircraft Serial Number 2a. Classification 2b. Category
19970713001 Jul 13 1997 2200 8900168 B FLIGHT RELATED
3. Type of Aircraft 4. Period Of Day 5. No Acft Involved 6. Nearest Installation
CH47D DAY 1 02347 - FT GREELY, AK
7. Accident Location a. Off Post b. Not On Airfield d. ALASKA
8. Organization Involved in Accident
Unit UIC7 UIC6 UIC5 UIC4 UIC3 UIC2 MACOM Station
WHT7B0 WHT7AA WDQKFF WDN6FF W32FAA 02956
B CO 4/123AB 6CBAVBD 6INFDIV USARPAC FT WAINWRIGHT, AK
9. Organization Accountable for Accident
WHT7B0 WHT7AA WDQKFF WDN6FF W32FAA 02956
B CO 4/123AB 6CBAVBD 6INFDIV USARPAC FT WAINWRIGHT, AK
10. Estimated Accident Cost
a. Total Loss b. Aircraft Damage c. Man Hrs d. Man Hrs Cost e. Other Mil Damage f. Civilian Damage
No $0 0 $0 $619933 $0
g. Injury h. Total This Aircraft i. Total Accident
$0 $619933 $619933
11. General Data
a. Mission S/M b. Flight Plan c. Data Recorder
S - SERVICE MULTI VFR No
13 - SUPPORT
10 - CARGO PICKUP/DELIVERY-SLING
d. Night Vision e. Fire f. Fluid Spillage g. Field Training
NONE No FTX (Unnamed)
12. Flight Data
a. Emergency Duration Phase of Operation
4.1 N - LOW LEVEL
AGL KIAS Weight Overgross
200 105 34500 No
b. Termination Duration Phase of Operation
4.1 N - LOW LEVEL
AGL KIAS Weight Overgross
200 105 34500 No
13. Type Event
40 - Flight Related 05 - Cargo 96 - Cargo Handling Equipment
14. Accident Cause Factors Human Error Material Failure Environmental
NO SUSPECTED NO
15. Summary
MULTIPLE TURNS LIFTING HOWITZERS. SECOND TURN HOWITZER SEPARATED FROM AIRCRAFT. AIRCRAFT RETURNED TO BASE.
16. COMPONENT AND PART FAILURE/MALFUNCTION DATA
Major Component Information
a. Nomenclature b. Type/Design/Series c. Part Number d. NSN e. MFG Code f. Part Serial No
CARGO/PERS HANDLING
Part Information
a. Nomenclature c. Part Number d. NSN e. MFG Code f. Part Serial No
VALVE SOLENOID 114HS1144 4820011140957 08080 W0533MK
g. Cause Failure Functional Group
Material Maintenance Design Manufacture 17 - CARGO AND PERSONNEL HANDLING 03 - HOOK
SUSPECTED 00 - 36 - SOLENOID
Type Failure Cause Failure
977 - PRESSURES ERRATIC - 999 - UNDETERMINED -
17. ENVIRONMENTAL
a. General (1) IMC (2) VMC (3) Unknown
b. Environmental Conditions
1. Weather Conditions 2. Other Conditions
(a) Hail (a) Animals
(b) Sleet (b) Fowl
(c) Fog (c) Surface
(d) Drizzle (d) Noise
(e) Rain (e) Chemicals
(f) Snow (f) Radiation
(g) Lightning (g) Glare
(h) Thunderstorm (h) FOD
(i) Gusty Winds (i) Temperature
(j) Freezing Rain (j) Vibration
(k) Other (k) Dust
c. Aircraft Icing No Yes d. Turbulence No Yes
19. MOON ILLUMINATION DATA
a. Above Horizon b. Visible c. Degrees Above Horizon d. Percent Illumination e. Clock Position
No Yes No Yes
20. WIRE STRIKE DATA
a. Wire Strike b. WSPS Installed c. WSPS Engaged
No Yes No Yes No Yes
d. WSPS Cut Wire e. WSPS Functioned f. Wires Struck
No Yes No Yes Number wires 0 Dia.(inches)
21. PERSONNEL DATA
Person # 1 c. Grade d. Sex e. Duty
W2 MALE PI - PILOT
f. SVC g. UIC h. Role i. On Controls
A - ACTIVE ARMY WHT7B0 N - NONE No Yes
j. Lab Test k. Hrs Slept 24 l. Hrs Worked 24 m. Hrs Flown 24
No Yes 8 8 5
n. RL o. FAC p. Injury q. MTDS Total Flt Hrs
1 2 3 1 2 3 - 0
Person # 2 c. Grade d. Sex e. Duty
E6 MALE CE - CREW CHIEF/FLIGHT ENGINEER
f. SVC g. UIC h. Role i. On Controls
A - ACTIVE ARMY WHT7B0 N - NONE No Yes
j. Lab Test k. Hrs Slept 24 l. Hrs Worked 24 m. Hrs Flown 24
No Yes 10 8 5
n. RL o. FAC p. Injury q. MTDS Total Flt Hrs
1 2 3 1 2 3 - 0
Person # 3 c. Grade d. Sex e. Duty
W2 MALE PC - PILOT IN COMMAND
f. SVC g. UIC h. Role i. On Controls
A - ACTIVE ARMY WHT7B0 N - NONE No Yes
j. Lab Test k. Hrs Slept 24 l. Hrs Worked 24 m. Hrs Flown 24
No Yes 10 8 4
n. RL o. FAC p. Injury q. MTDS Total Flt Hrs
1 2 3 1 2 3 - 0
Person # 4 c. Grade d. Sex e. Duty
E5 MALE CE - CREW CHIEF/FLIGHT ENGINEER
f. SVC g. UIC h. Role i. On Controls
A - ACTIVE ARMY WHT7B0 N - NONE No Yes
j. Lab Test k. Hrs Slept 24 l. Hrs Worked 24 m. Hrs Flown 24
No Yes 10 8 7
n. RL o. FAC p. Injury q. MTDS Total Flt Hrs
1 2 3 1 2 3 - 0
22. IMPACT/PROTECTIVE/ESCAPE/SURVIVAL/RESCUE DATA
a. Aircraft Space Compromised b. Escape/Survival Difficulties c. Protective/Restraint Equip Functioned
No Yes No Yes No Yes
24. FINDINGS AND RECOMMENDATIONS
Findings
FINDING PENDING TEARDOWN ANALYSIS FROM CCAD. CONTROL NUMBER 97-009. SHIP DATE 22 JUL 97. FINDING 1 (PRESENT AND CONTRIBUTING: MATERIEL FAILURE): WHILE AT 200 - 300' AGL IN CRUISE FLIGHT WITH A SLING LOAD, THE CH47D HAD A SUSPECTED FAILURE OF THE CENTER CARGO HOOK NORMAL RELEASE VALVE (P/N 114HS114-4). THE PRESSURE TO MAINTAIN THE HOOK CLOSED IS 2100 PSI. A MOMENTARY SURGE IN HYDRAULIC PRESSURE COULD OVERRIDE THE 2100 PSI PRECHARGE WHICH KEEPS THE HOOK IN ITS SEATED POSITION. ONCE THE SURGE WAS TERMINATED THE PRECHARGE PRESSURE OF 2100 PSI WOULD CLOSE THE HOOK. THE HOOK HAS TO BE FULLY OPENED IN ORDER FOR WARNING INDICATIONS TO ILLUMINATE. ANY OTHER MEANS TO OPEN THE HOOK STARTS THE HOOK INTO A PROCESS THAT CANNOT BE HALTED AND THAT WOULD ILLUMINATE THE MASTER CAUTION PANEL WITH RELATED SEGMENT LIGHTS. A BAD RELEASE VALVE KEEPS THE HOOK FROM REMAINING CLOSED BUT ALLOWS SUFFICIENT PRESSURE TO PROHIBIT THE HOOK FROM CYCLING THROUGH ITS COURSE. THE HOOK CAN BE CLOSED ONCE THE VALVE RECOVERS. FINDING(S) LISTED BELOW DID NOT CONTRIBUTE TO THIS ACCIDENT. HOWEVER, IF LEFT UNCORRECTED, THEY COULD ADVERSELY AFFECT THE SAFETY OF AVIATION OPERATIONS. FINDING 2: (PRESENT BUT NOT CONTRIBUTING): DURING THE PREMISSION PLANNING THE PC FAILED TO RECORD A RISK ASSESSMENT FOR THE MISSION IN ACCORDANCE WITH AR 95- 1, APPLICABLE ATMS, AND LOCAL SOPS. FAILURE TO CONDUCT A PROPER RISK ASSESSMENT COULD RESULT IN A CREW PERFORMING A MISSION OUTSIDE THE SCOPE OF IMMEDIATE CHAIN OF COMMAND APPROVAL. FINDING 3: (PRESENT BUT NOT CONTRIBUTING): DURING THE PREMISSION PLANNING, THE AIR MISSION COMMANDER (AMC) FAILED TO RECORD BACK BRIEF FOR THE BRIEFING OFFICER IN ACCORDANCE WITH AR 95-1, APPLICABLE ATM'S, AND LOCAL SOPS. FAILURE TO CONDUCT BACK BRIEFS COULD RESULT IN A MISUNDERSTOOD MISSION BY THE AMC, PCS, AND CREWS. FINDING 4: DURING THE POST ACCIDENT PHASE THE PC RETURNED TO FT WAINWRIGHT AS DIRECTED BY THE AMC. IN ACCORDANCE WITH UNIT STANDING OPERATING PROCEDURES FOR FINDING INADVERTENTLY RELEASED LOADS, "THE PC WILL LAND NEAR THE DROPPED LOAD IF POSSIBLE AND CEASE ALL FLIGHT OPERATIONS UNTIL AN INVESTIGATION OR OTHER APPROPRIATE ACTION IS CONDUCTED." FAILURE TO REMAIN ON STATION EXPENDS FUTURE RESOURCES ALLOCATED FOR TRAINING. .... FINAL CCAD FOR AIRCRAFT CH47D, SERIAL NUMBER 89-00168: CONCLUSIONS - 1. NO LEAKAGE OR DEFECTS WERE NOTED DURING OPERATIONAL TEST OF THE SOLENOID VALVE, P/N 114HS114-4, S/N W0533 MK. THE VALVE WAS TESTED IN ACCORDANCE WITH (IAW) TM 55-1520-240-23, TASK 7-264, PAGE 7-855. NO MECHANICAL OR MATERIAL DEFECTS WERE NOTED DURING DISASSEMBLY AND INSPECTION OF THE SOLENOID VALVE IN ACCORDANCE WITH TM 55-1520-240-23, TASK 7-262, PAGE 849. 2. THE CARGO HOOK, P/N 145E5505-12, S/N 599A, WAS TESTED AT CORPUS CHRISTI ARMY DEPOT ON A TEST BENCH IN ACCORDANCE WITH TM 55-1520-240-23, TASK 16-7.1.1, PAGE 16-28.9. NO OPERATIONAL DEFECTS WERE NOTED. DISASSEMBLY AND EXAMINATION REVEALED NO MATERIAL OR MECHANICAL DEFECTS WITH THE CARGO HOOK ASSEMBLY.
Recommendations
RECOMMENDATION 1: A. UNIT-LEVEL ACTION: CONDUCT A BENCH TEST OF THE CENTER CARGO HOOK NORMAL RELEASE VALVE FOR THE ENTIRE FLEET. CONDUCT A ROUTINE INSPECTION OF THE VALVE DURING EACH PHASE INSPECTION. B. HIGHER-LEVEL ACTION: ENSURE ABOVE RECOMMENDATION IS ACCOMPLISHED. C. DA-LEVEL ACTION: (1) COMMANDER, U.S. ARMY SAFETY CENTER, INFORM INTERESTED AGENCIES OF THE FACTS AND CIRCUMSTANCES REGARDING THIS ACCIDENT AND RESULTS OF THE BOARD. (2) PROGRAM EXECUTIVE OFFICER - AVIATION TAKE ACTION TO HAVE THE MANUFACTURER'S HYDRAULIC SOLENOID INSPECTED AND REVIEWED. ENSURE PROPER QUALITY AND PERFORMANCE OF THE SOLENOID. INSTALL AN INLINE VISUAL PRESSURE GAUGE TO MONITOR HYDRAULIC PRESSURE IN THE CARGO HOOK SYSTEM TO BE VERIFIED BY THE CREW CHIEF. (3) PUBLISH AN AVIATION SAFETY ACTION MESSAGE (ASAM) TO INCLUDE A ONE TIME INSPECTION OF THE CENTER CARGO HOOK NORMAL RELEASE VALVE DURING EACH PHASE INSPECTION. RECOMMENDATION 2: A. UNIT-LEVEL ACTION: CONDUCT AVIATOR'S CLASSES WITH AN EMPHASIS ON PREMISSION PLANNING PROCEDURES AND RISK ASSESSMENT. B. HIGHER-LEVEL ACTION: ENSURE UNIT PERFORMS RECOMMENDATION 2A. C. DA-LEVEL ACTION: NONE. RECOMMENDATION 3: A. UNIT-LEVEL ACTION: CONDUCT AVIATOR'S CLASSES WITH AN EMPHASIS ON PREMISSION PLANNING PROCEDURES INCLUDING MISSION BRIEFINGS AND BACK BRIEFS. B. HIGHER-LEVEL ACTION: ENSURE UNIT PERFORMS RECOMMENDATION 3A. C. DA-LEVEL ACTION: NONE. RECOMMENDATION 4: A. UNIT-LEVEL ACTION: CONDUCT AVIATOR'S CLASSES WITH AN EMPHASIS ON THE PRE-ACCIDENT PLAN AND INADVERTENTLY RELEASED LOADS. FURTHER RECOMMEND THE UNIT REVIEW THE STANDING OPERATING PROCEDURES FOR INADVERTENTLY RELEASED LOADS AND CHANGE PROCEDURES OR COMPLY. B. HIGHER-LEVEL ACTION: REVIEW SOP TO ENSURE IT MEETS THE COMMANDER'S INTENT. C. DA-LEVEL ACTION: NONE. .....STATEMENT OF REVIEWING OFFICIALS.....COMMENT #1: 1. CONCUR WITH THE FINDINGS AND RECOMMENDATIONS OF THE ACCIDENT INVESTIGATION BOARD. 2. ACTIONS SPECIFIED IN RECOMMENDATION PERTAINING TO THIS LEVEL OF COMMAND WERE IMPLEMENTED. SHERI L. TONNER, MAJ, AV, COMMANDING. COMMENT #2: 1. CONCUR WITH THE FINDINGS AND RECOMMENDATIONS OF THE ACCIDENT INVESTIGATION BOARD. 2. ACTIONS SPECIFIED IN RECOMMENDATION PERTAINING TO THIS LEVEL OF COMMAND WERE IMPLEMENTED. MICHAEL E. MOODY, LTC, AV, COMMANDING. COMMENT #3: CONCUR WITH THE FINDINGS AND RECOMMENDATIONS OF THE ACCIDENT INVESTIGATION BOARD. ROBERT A. HAMMERLE, COL, AV, COMMANDING. COMMENT #4: CONCUR WITH THE FINDINGS AND RECOMMENDATIONS OF THE ACCIDENT INVESTIGATION BOARD. KENNETH W. SIMPSON, MG, COMMANDING.