While conducting battle field circulation of troops in support of NTC 09-08, the CH-47D serial number 8900168 was making an approach to an area known as FOB Denver. Although minor blowing dust was present, it was light enough the crew never lost visibility to the ground. The PI in the right seat was on the controls and initiated a hover down. The rear landing gears contacted first, followed by the front landing gear. When the aircraft's left front landing gear contacted the ground, it sheared and folded under the aircraft. The folding of the landing gear caused a left roll of the aircraft; the PI reacted to the roll by moving the cyclic aft and right. The PC in the left seat rode the cyclic with the PI and performed an Emergency Engine shutdown in an effort to keep the rotor blades from hitting the ground. The Crew Chief who was riding in the aft portion of the cabin exited the aircraft, discovered the aircraft was leaking fuel and announced the situation over the ICS. The crew and passengers exited the aircraft and ensured that all personnel were accounted for.
16. COMPONENT AND PART FAILURE/MALFUNCTION DATA
No Component/Part Data
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
PC - PILOT IN COMMAND
f. SVC
g. UIC
h. Role
i. On Controls
A - ACTIVE ARMY
WCYMB0
N - NONE
No Yes
j. Lab Test
k. Hrs Slept 24
l. Hrs Worked 24
m. Hrs Flown 24
Yes No
10
10
0
n. RL
o. FAC
p. Injury
q. MTDS Total Flt Hrs
1 2 3
1 2 3
-
650
Person # 2
c. Grade
d. Sex
e. Duty
E5
MALE
FI - FLIGHT ENGINEER INSTRUCTOR
f. SVC
g. UIC
h. Role
i. On Controls
A - ACTIVE ARMY
WCYMB0
N - NONE
No Yes
j. Lab Test
k. Hrs Slept 24
l. Hrs Worked 24
m. Hrs Flown 24
Yes No
9
8
0
n. RL
o. FAC
p. Injury
q. MTDS Total Flt Hrs
1 2 3
1 2 3
-
761
Person # 3
c. Grade
d. Sex
e. Duty
E4
MALE
CE - CREW CHIEF/FLIGHT ENGINEER
f. SVC
g. UIC
h. Role
i. On Controls
A - ACTIVE ARMY
WCYMB0
N - NONE
No Yes
j. Lab Test
k. Hrs Slept 24
l. Hrs Worked 24
m. Hrs Flown 24
Yes No
10
8
n. RL
o. FAC
p. Injury
q. MTDS Total Flt Hrs
1 2 3
1 2 3
-
590
Person # 4
c. Grade
d. Sex
e. Duty
W2
MALE
PI - PILOT
f. SVC
g. UIC
h. Role
i. On Controls
A - ACTIVE ARMY
WCYMB0
S - SUSPECTED
No Yes
j. Lab Test
k. Hrs Slept 24
l. Hrs Worked 24
m. Hrs Flown 24
Yes No
12
4
0
n. RL
o. FAC
p. Injury
q. MTDS Total Flt Hrs
1 2 3
1 2 3
-
338
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 1: (Human Error) While conducting battlefield circulation, in support of NTC rotation 09-08 on short final to landing at FOB Denver. The Pilot in the right seat failed to recognize that he was drifting left at touchdown. The Standards for Task 1038 Perform Hovering Flight, of TC 1-240, Aircrew Training Manual Cargo Helicopter, CH-47D/F, dated October 2007, states: Perform a smooth, controlled descent with minimal drift at touchdown. The drift at touchdown overstressed the forward left landing gear from the outboard to the inboard side causing the landing gear to shear. The shearing of the landing gear caused a left roll of the aircraft when it came to rest on the forward left fuel cell causing damage to the airframe skin, stringer between Stations 140 and 160. Additional damage was to the bottom left hand side of the fuselage from Station 260 to Station 300, Left hand BL 50 to Left hand BL60 and Water line -30 to -37. It is the opinion of this board that the root cause of the accident was a training failure. The PI was not able to recognize his drift due to his lack of experience under NVG's (43 total hours) combined with his lack of experience with blowing dust. How reason contributed to mistake: The lack of depth perception and distance estimation associated with flight using NVG's causes the detection of lateral drift to be significantly harder than during daylight conditions. The blowing dust intensifies the difficulty especially when combined with an area of low contrast. The Pi's inexperience with blowing dust under NVG'S caused him to fail to recognize his drift. The PI had not flown under NVG's in the two months preceding the accident and hadn't flown NVG's in the six months prior to that. FINDING 2: (Present and Non-Contributing: Human Error-Unit) The PI was not current in Night Vision Goggle (NVG) flight on the day of the incident. His currency ran out on 17 November 2008. He was not IAW AR 95-1 dated February 2006, page 21. paragraph 4-18 (b), TC 1-240 dated October 2007, page 2-15 paragraph 2-6. Had the Platoon Leader tracked his personnel's flights more accurately, the PI would not have been scheduled for this flight. The PI is also at fault for not tracking his own currency requirements and should have brought the currency issue up to his Chain of Command.
Recommendations
Recommendation 1: Unit Level Actions: Commander. B Company 1-52 AVN, task Platoon Leaders. Standards Section, and Operations Officer to ensure that crewmembers have an appropriate amount of experience for the conditions. Crewmembers that don't have an appropriate amount of experience for the conditions should be assigned to fly with Instructor Pilots, Unit Trainers, or Senior Aviators. Higher Level Actions: None. Army Level Actions: Commander USACRC: Make the events of this accident known by publishing them in Knowledge magazine and add this accident to the CRC data base for trend analysis. Recommendation 2: Unit Level Actions: Commander B Company 1-52 AVN, task Platoon Leaders in conjunction with Operations personnel to verify currency for all soldiers and produce a better tracking system to ensure no other soldiers become un-current without the knowledge of the Chain of Command. Higher Level Action: None. Army Level Actions: None. The PI was not current in Night Vision Goggle (NVG) flight on the day of the Incident. His currency ran out on 17 November 2008. That Is, he was not IAW AR 95-1 dated February 2006, page 21, paragraph 4-18 (b), TC 1-240 dated October 2007, page 2-15, paragraph 2-6. Had the Platoon Leader tracked his personnel's flights more accurately, the PI would not have been scheduled for this flight. The PI is also at fault for not tracking his own currency requirements and should have brought the currency issue up to his Chain of Command. . . . . STATEMENT OF REVIEWING OFFICIALS. . . . Comment 1: Concur. Morford, Zachariah G., O3, B Co. 1-52 AVN. Comment 2: Concur. Peitz, Kelly J., O5, 1-52 AVN.