Final Report of Accident Investigation of helicopter 9N-AHJ Page No. 1 Helicopter Accident Investigation Commission Kathmandu, Nepal. FINAL REPORT Accident of Shree Airlines (P) Ltd. Helicopter 9N-AHJ (MI-8 MTV-1) Accident Date : 23 rd September 2006 Accident Site : Lelep V.D.C.- 9 Phaledanda, Taplejung Submitted to, The Government of Nepal on 4 th December 2006
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Final Report of Accident Investigation of helicopter 9N-AHJ
Mr. Puspa Raj Koirala, Joint Government Attorney, Member
Office of the Attorney General
Col. Pramod Kumar Lama, No. 11 Brigade, Gaucher Member
Mr. Sanjeev Shrestha, Engineer, Simrik Airlines (P.) Ltd. Member
Mr. Bijaya Kumar Vaidya, Deputy Director General,
Department of Hydrology and Meteorology Member
Brig. (Retd.) Dr. Khagendra Bahadur Shrestha Member
Mr. Yajna Prasad Gautam, Joint Secretary,
Ministry of Culture, Tourism & Civil Aviation
Member - Secretary
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 3
Synopsis On 23rd September 2006, the ill-fated MI-8 MTV-1 helicopter 9N-AHJ owned and operated by
Shree Airlines Pvt. Ltd., was on chartered flight to Ghunsa, Taplejung. It departed from Fungling,
Taplejung at 09:32 LT and weather was cloudy with light drizzle. The helicopter during flight reached
maximum altitude 3400 m. and reported on ground Ghunsa at 09:51 LT.
The flight was in command of Capt. Klim Kim and this was his first flight to Ghunsa. The
weather at Ghunsa was cloudy. The helicopter, with 4 crew members and 20 passengers and TOW 10,344
kg, took-off at 10:45 LT (0500 UTC) and entered into cloud while clearing Ghunsa valley. Then
helicopter climbed up to 3885 m. with air speed 62 km/hr in 2 min 30 seconds and flight was into clouds.
At this moment, pilot observed that helicopter was only 60 m. above the ground, which indicated that
peak was somewhere around them. Flying in IMC, he decreased the airspeed and tried to achieve high
rate of climb with application of maximum power. Helicopter reached up to 4033 m. and this moment
speed dropped to 31 km/hr. The combined effect of speed below 31 km/hr, low main rotor RPM,
helicopter weight at that altitude and flying into the cloud (IMC) contributed to sink the helicopter from
4033 m. In 13 seconds, the helicopter descended to 3990 m. with further drop in airspeed of 12 km/hr and
main rotor RPM 91% and faced impact in steep rugged mountain terrain. Fire was immediately registered
in helicopter. All other parts were found in limited area in burnt conditions. No survival was found.
The Commission has determined the primary contributing factors for this accident are entering the
cloud intentionally in the unfamiliar terrain of high altitude mountains, poor crew coordination and poor
area map information. This helicopter was certified only for Visual Flight Rules (VFR).
The Commission has presented its safety recommendations needed to be adopted by the Civil
Aviation Authority of Nepal, Shree Airlines and other Airlines. The objective of these recommendations
is the prevention of the accident of this nature in future.
Injuris to Person FATAL Seriously injured Minor injured Non injured
Crew - 04 00 00 00
Passenger - 20 00 00 00
Other - 00 00 00 00
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 4
1. Factual Information
1.1 History of the Flight
At about 0500 UTC on 23rd September 2006, a MI-8 MTV 1 helicopter with registration 9N-AHJ
of Shree Airlines (P.) Ltd, departed Ghunsa, Taplejung on a charter flight to Fungling, Taplejung in the
eastern part of Nepal with 4 crew members and 20 passengers on board and crashed at Lelep V.D.C-9
Phaledanda. The actual flight plan was not submitted as the helicopter was taking-off from an unmanned
helipad.
9N-AHJ had departed Kathmandu on 22nd September 2006 for Taplejung with the intention of
making the flight from Fungling to Ghunsa on the next day. On the way to Taplejung it was to land at
Rampurtar, Okhaldhunga to pick up Hon. State Minister Gopal Rai but could not land at Rampurtar and
instead landed at Okhaldhunga due to weather. Later the helicopter arrived at Taplejung on the same day.
The main programme of charter party World Wildlife Fund (WWF) was launched at Fungling on 22nd
September 2006 and the helicopter made a night stop at Fungling. Throughout the day the weather
condition at Taplejung was frequent rain and cloudy.
On 23rd September 2006 also the weather condition was not good. It was totally overcast with
frequent light rain. The commander of helicopter 9N-AHJ intended to complete the planned flight to
Ghunsa when he felt a little improvement of weather. After getting listed passengers on board, the
helicopter departed Fungling at about 0932 LT for Ghunsa and arrived there at 0951 LT. As per eye
witnesses after reaching Ghunsa, the passengers proceeded to the programme venue, completed their
programme within a short period of time and then came back to the helipad for departure. As per local
people, weather condition at Ghunsa and surrounding was cloudy with frequent rain and drizzle. All the
surrounding hills including hill tops and also foothills to east, west and south were completely covered up
but north side hilltops were partially visible. The helicopter took-off from Ghunsa at or about 10:45 LT
i.e. 0500 UTC with an approximate load of 10334 kg. The eye-witnesses told the Commission that within
a few moment of take-off the helicopter disappeared into clouds. Then approximately about 3 minute
after take-off an unusual sound like 'Bang' was heard by the local people at Ghunsa and after few minutes
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 5
later another big sound was heard but nothing was observed visually. Following the events, the local
people of Ghunsa called Fungling and gave the detail information. The message was relayed to
Kathmandu and Rescue Co-ordination Center (RCC) at Tribhuvan International Airport was activated
immediately on 23rd September 2006 at 1400 LT. Air Dynasty Helicopter 9N-AGU flying in Taplejung
area was requested to attempt search for 9N-AHJ but it could not fly the probable area due to bad
weather.
On 24th September 2006 with no improvement in weather, a ground search team was sent to
Ghunsa including a 15 member team from Nepal Mountaineering Association along with local people.
Finally the ground Search and Rescue team located the crash site at Lelep V.D.C.-9 Taplejung (Co-
ordinates 273845 N 0875411 E) at 3990 m. from sea level on a steep rocky terrain and found the aircraft
completely destroyed into several pieces and totally burnt. There was no survival and almost all except
one body was found in a burnt and charred condition. The rescue team recovered dead bodies and FDR
but could not find the CVR. All the dead bodies and body parts including FDR were dispatched to
Kathmandu subsiquently. FDR read out was done at Russia.
1.2 Injuries to persons:
Injuris to Person FATAL Seriously injured Minor injured Non injured
Crew - 04 00 00 00
Passenger - 20 00 00 00
Other - 00 00 00 00
1.3 Damage to aircraft:
The helicopter caught fire upon impact with rocky terrain. Main rotor blades and tail rotor blades
were broken into pieces and scattered around the site. Nose landing gear was detached from the airframe.
All other parts were found in a limited area without much scattering. Cockpit, central part of fuselage and
some parts of tail boom were found totally burnt to ashes and the remaining parts were found in a
damaged condition.
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 6
1.4 Other Damages:
The accident site consisted of steep rugged cliff without any habitation and vegetation at an
altitude of 3990 m. So no damage was caused to private property and persons.
1.5 Personal Information:
Capt. Klim Kim
Captain : Male Date of Birth : 10.03.2054. Nationality : Kyrgyzstan Republic License : 00018 Issued by : Kyrgyzstan Republic Validity : 16.06.2007 Rating at type, and instructor : MI-17 (MI-8 MTV, MI-8 AMT) Nepalese License : 143 Authorization by : Civil Aviation Authority of Nepal Validity : 16/12/2006 Last Medical : 16/06/2006 Pilot Proficiency Check : 20/11/2005 Previous accident/incident : None
He had received the following trainings and attended the following courses in Kathmandu:
i. Training in Aeronautical Information Publications (AIP), Nepal from 30 August 2005 to 04
September 2005, conducted by Civil Aviation Authority of Nepal,
ii. Passed English Language Skill test with remarks ‘satisfactory’ on 13 September 2005, taken
by Civil Aviation Authority of Nepal
iii. Passed Pilot Proficiency & Upgrading Check on 20 November 2005 with remarks
‘Satisfactory’,
iv. 6-hours training course in CRM on 21 November 2005
v. Refresher Course in Flight Operation Regulation (FOR) on 24 November 2005,
vi. Refresher Course on Transport of Dangerous Goods on 25 November 2005.
vii. Technical & Performance Refresher Course in MI-17 helicopter from 22 November 2005 to
25 November 2005,
viii. High Altitude Familiarization/Practice carried out on 01.12.2005 and 02.12.2005 with
Instructor pilot Captain Koleniscov Vladimir at Syangboche, Everest Base Camp area
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 7
He also had following special remarks (Restriction/Rights) from his country and valid up to 26
May 2006:
i. Rated for Radiotelephony operation in English,
ii. Helicopter MI-8T/MI-8MTV, sling cargo ferry over plain, mountain area,
iii. Helicopter MI-8T/MI-8MTV-1, cargo dumping and parachute landing,
iv. Helicopter MI-8T/MI-8MTV-1, cross country flight & airborne air field selection up to
altitude 4500 m,
v. Helicopter MI-8T/MI-8MTV-1, cross country flight & airborne air field selection up to
altitude 5000 m
Flight hours total 11977:36
Flight hours on Type 3777:36
Hours flown in last three months 122:47
Hours flown in last 30 days 88:46
Hours flown in last 7 days 29:51
Professional Training Flight Training, Russia
Aircrafts flown MI-8T, MI-8MTV, MI-AMT
Date of joining Shree Airline 25 August 2005
Career Progression Senior Captain
Earlier Professional Experience Flying in Kyrgyzstan
Co-pilot, Capt. Mingma Tshering Sherpa
Captain : Male Date of Birth : 15.11.1972. Nationality : Nepalese License : ATPL 17 (H) Issued by : Civil Aviation Authority of Nepal Rating at Type, Pilot in command, Day only, July 2003
MI-17-IV (MI-8MTV)
Validity : 30/09/2006 Pilot Proficiency & Upgrading Check : 21.03.2006 Last Medical : 22.09.2005 Previous accident/incident : None
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 8
i. Successfully completed High Altitude Training flight up to 13000 ft. on 10.02.2006,
13.03.2006 and 17.03.2006 in Heli Hansa, Instructor A. Tchirva, Syangboche Airfield.
ii. Route Check, satisfactory, KEP to DUNAI, 30.09.2005, in Heli Hansa, Instructor V.
Koleniscov
iii. Recurrent Training, found proficient, 29.04.2005, in Heli Hansa, Instructor V. Koleniscov
iv. Successfully completed Refresher Ground Class Training, Technical and Performance, on Mi-
17 Helicopter on 28 02.2005, Simrik Air
v. Successfully completed Refresher Ground Class Training on Company Resource Management
(CRM), Flight Operations Requirements (FOR), and Transport of Dangerous Goods 03 – 05,
March 2005, Simrik Air
Total Flight hours 3476:20
Flight hours on Type 3137:55
Hours flown in last three months 28:20
Hours flown in last 30 days 08:42
Hours flown in last 7 days 08:42
Professional Training CPL Training in Kremenchug, Ukraine in 1995
Aircrafts flown MI-17-1V
Date of joining Shree Airline 17 September 2006
Career Progression Captain
Earlier Professional Experience
Co-pilot in Asian Airlines after coming back from Russia
Joined Heli Hansa from Sept, 2004
Then Shree Airlines on from 17 September 2006
He was overweight. He had undertaken Glucose tolerance tests in Sept 2004 and they were in
normal range. He was considered to be a good, knowledgeable, experienced and safety conscious
pilot. He had flown together with Capt Klim for the first time only from 21 Sept 2006.
20. 07:34 Stop of Operation of FDR 0 0 460 460 0 0 3990 148 0
1.12. Wreckage information
The helicopter was found almost completely burnt and toppled on its left side with scattering of
its parts in a limited area.
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 24
A. Cockpit : Both instrument panels, wind shields, seats, control sticks, auto-pilot, circuit
breaker, system indicators, electrical blocks in cockpit were also burnt completely.
Most of these parts were found in the form of ashes. Cockpit frames were also
found in the condition of ashes or in a melted down condition.
B. Central part of Fuselage : Central part of fuselage of helicopter MI-8MTV-1 consist of 23 frames.
First 10 frames were found in the conditions of ashes or in a melted down condition.
Frames, stringers, floors, passenger seats etc. were completely burnt. Remaining
frames after 10th frame were also burnt. Last row seats were partially burnt. Rear
portion of external fuel tanks were not completely burnt. Some maintenance
accessories (funnel, ladder etc.) were found unburnt. Rear clam-shell doors of the
helicopter was found in pieces in a partially burnt condition. Rearmost part of
central section of fuselage was found in a partially burnt condition.
C. Tail Boom : Out of 17 frames of the tailboom, initial frames were completely burnt and
remaining part including stabilizer, tail guard were found unburnt but in a damaged
condition.
D. Pylon : Pylon was found in a damaged condition but unburnt.
E. Landing Gears : Nose Landing Gear along with its shock absorber was found about 28 meters away
to the rear and to the left of the wreckage. Main Landing Gear tyres were burnt
completely and shock absorbers with brace struts were found partially burnt.
F. Main Rotor and Tail Rotor : Main rotor blades were found with 70% of its length scattered in
different directions. Remaining 30% of its length attached with the hub were found
in a burnt condition.
G. Engines : Both engines TV3-117VM engines of helicopter were found burnt completely
except engine exhaust pipe. Components of engines were left in the form of ashes or
in melted down condition.
H. Main Gear Box : Main Gearbox of helicopter was completely burnt down to ashes and melted down.
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 25
I. Flight Data Recorder : FDR was recovered with its casing in a partially burnt condition in the rear
side of fuselage.
J. Cockpit Voice Recorder : CVR was searched with several attempts but it was not recovered.
1.13 Medical and Pathological Information
Identification: Medico-legal investigation of all the bodies, body parts and remains retrieved from the
crash site were done in Kathmandu Autopsy Centre/Department of Forensic Medicine, Institute of
Medicine, Tribhuvan University, Maharajganj. Further expert assistance was provided by Finnish-US
team composed of two members, a Detective Chief Inspector and a Senior Forensic Pathologist, of the
Finnish-DVI team and two specialists, a Forensic Odontologist and a Senior Forensic Anthropologist
from the US, JPAC Central Identification Laboratory.
Only one body was in good condition. Few were substantial body parts, others were only limited body
parts and yet others were only teeth and a few bones. All of them, except one were severely burnt and
charred.
Only 10 of 24 occupants could be identified. Of them seven were identified on the basis of recognizable
facial features, personal belongings and jewelry present with the bodies. Five had positive dental
identification and of them four had only dental identification from the very limited remains. One was
identified on DNA analysis only.
Injuries to the Occupants: Only one occupant, found outside the helicopter was in good condition
though he had laceration on the scalp and multiple closed fractures of the ribs on the left side. Rest of the
occupants were inside the helicopter. They all received very severe injuries due to high decelerative force
during the final impact. Those substantial bodies received fractures of the skull and facial bones
extruding the brain tissue, fractures and dismembering of distal parts of upper and lower limbs, fractures
of chest cage and vertebrae and in some exposing lung tissue, and abdominal injuries with opening and
exposure of and injury to organs. Others consisted of only torso or portion of body part and some only
teeth and adjoining bone structures with some tissue. All of them except one lying outside the helicopter
received severe burn and were extensively charred.
Autopsy findings of Decedents of Shree Airlines 9N-AHJ Helicopter Accident at Ghumsa
Body/
Remains Head, Face &
Neck Torso Upper Limbs Lower Limbs
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 26
A – DB 1 Mingma Norbu Sherpa - Identified at site by local people; facial features & clothes
Laceration, 5 cms A-P scalp over mid top, muscle deep right upper eyelid; Contusion inner aspect upper lip; Abrasions multiple punctuate & linear right cheek bone,
Multiple closed fracture left anterior lateral aspect of rib cage; Abrasion left shoulder, left scapular region; No external injuries in the abdomen and pelvis
Contusion right thigh, left fore arm; Abrasion, multiple punctuate dorsum right hand
Contusion posterior mid 3rd of right thigh, left knee
C – DB 3 Ms Jennifer Lynn Hedley – identified by sex, physical characteristics, personal item (ring) and dental identification
All bones of skull missing;, head burst open, brain tissue missing; extensive 1st to 3rd degree burn, face and neck
Multiple fractures vertebral column, anterior rib cage; 1st to 3rd degree burn chest, both clavicles burnt, right lung; Left breast tissue present in anterior chest; Whole of posterior rib cage burnt with multiple burns, fractures of left half; Abdomen burst open, 1st to 3rd degree burn, exposing liver and abdominal contents, Multiple fractures of pelvis, both ilio-sacral dislocation; sacral region of vertebral column fracture
Multiple fractures, Missing Right arm below mid humerus; Left burnt & fracture of mid humerus; burn left forearm and dorsum of hand with burn
Multiple fractures; Missing Right below mid tibia, whole right thigh burn, Right leg burn exposing burnt bones; Whole Left. thigh burnt, Left leg burnt exposing burnt lacerated muscles and fractured bones; dorsum of Left. foot burnt and fractured, attached to leg by a muscle flap only
D – DB 4 Dr. Tirtha Man Maskey – Identified by necklace & locket
Head & face completely charred, scalp missing from the top and back, remaining scalp charred
Muscles of anterior chest missing, anterior left rib cage charred exposing underlying cooked lungs; vertebral column fractured at lumbar region with attachment only by a strap of muscle, liver and gall bladder not discernible due to charring;Genital organs missing, Left half of pelvis fractured; all soft tissues of pelvic region cooked
Right shoulder joint dislocated; upper limbs heat contracture
Upper half of both thighs cooked, both femurs charred and broken at the middle, Parts distal to mid third on both sides missing
F – DB 6 Dr. Bijnan Acharya, Identified based on DNA analysis
Skull bones fragmented and burnt, with cooked brain tissue; broken remains of cervical spines; some fragments of jaw bones with some teeth attached, burnt
Left scapula with charred flesh attached; portion of upper spine & ribs, 6 pieces of vertebrae, burnt; Abdomen and pelvis missing
Humeral head only, rest missing
Missing
H – DB 8 Min. Gopal Rai, identified by clothes and facial features, though burnt
Closed fracture bones of cranial and facial skul; Face and neck 1st to 2nd degree burn; upper jaw right 1st premolar burnt,
Upper half of anterior chest 1st to 2nd degree burn, lower half below nipples charred; Both clavicles and ribs on both sides of anterior chest multiple closed fracture; Whole of
Right, 1st to 3rd degree burn; soft tissue of dorsum of distal arm and forearm missing, dislocation of elbow joint, and heat
Both, muscles of superior two-third avulsed; all parts distal to two-third of thighs are missing
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 27
right canine and 2 incisors fractured, 2nd left incisor fractured
posterior trunk charred; Multiple fractures posterior rib cage; Abdomen burst open with viscera exposed and partially burnt, Perinium burnt, genitalia charred
contracture of wrist and fingers; Left, 1st to 3rd degree burn, compound fracture and dislocation of wrist
T – DB 20 Capt. Klim Kim - Identified by the watch in his wrist
Not present Not present Left upper limb with scapula, charred; arm exposed to muscle layer; distal phalanges of all fingers missing (metal wire entangled between the fingers).
Not present
Dr. Harkha Gurung - Identified on the basis of dentures
Soft tissue of scalp avulsed from top of the head to the anterior; parts of both parietal bones missing,
Muscles of both thigh extensively lacerated and charred, Left. femur fracture;, avulsed lacerations both legs; dorsum of both feet missing from distal 3rd of leg
Mr. Pauli A. Mustonen, Dental identification
Teeth, Missing Missing Missing
Mr. Matthew Stewart Preece, Dental identification
Teeth Missing Missing Missing
F/E Safronov Vallery, Dental identification
2 pairs of crown & bridge
Missing Missing Missing
Followings could not be identified from the examination of body parts and remains
Ser.No. Name Ser.No. Name 1. Mrs. Mina Rai 8. Mr. Bijaya Kumar Shrestha 2. Dr. Damodar Prasad Parajuli 9. Dr. Chandra Prasad Gurng 3. Mr. Narayan Prasad Poudyal 10. Mr. Hem Raj Bhandari 4. Mrs. Yeshi Lama 11. Dr. Jill Bowling Schlaepfer 5. Mr. Dawa Tshering Sherpa 12. Ms. Margarate R. Alexender 6. Mr. Sunil Prasad Singh 13. Capt. Mingma Tshering Sherpa 7. Mr. Sharad Kumar Rai 14. C/A Guruwar Tandul
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 28
Biochemical and Toxicological Examination: Biochemical and toxicological examination in the crew
could not be done due to unavailability of proper tissue.
Fire: There was post impact fire which devoured the passenger compartment and cockpit along with most
of the occupants, leaving behind extensively burnt and charred bodies or remains and ashes.
1.14. FIRE' in Helicopter :
As per flight data recorder read out, 'FIRE' was registered by FDR simultaneously with impact on rocky
cliff 2 minute 58 seconds after take-off from Ghunsa.
As per the technical documents, fire Extinguishing System in MI-8MTV-1 Helicopter 9N-AHJ includes
the following:
(a) Four compartments of the helicopter are protected by the system :
(i) Left Engine,
(ii) Right Engine,
(iii) Main Gearbox and APU,
(iv) Kerosene Heater
(b) 'FIRE' Detection Process : (i) Altogether 42 fire detectors are placed in the above mentioned four
compartments for the detection of 'FIRE'.
(ii) When the temperature in any compartment reaches above 150ºC or the
rate of increase of temperature in any compartment is more than
2º/second then the fire detector sends the signal of 'FIRE' in the
respective compartment to 'FIRE Warning System SSP-FK'.
(c) FIRE Warning Process : It includes a block SSP-FK for warning purposes when it receives a signal of
'FIRE'. This system sends the signal of 'FIRE' in the respective compartment
to the following systems:
(i) Master warning signal "FIRE" in left instrument panel;
(ii) Voice warning system 'RI-65' gets the signal of 'FIRE' and it warns
crew members "Fire in ........... compartment" with a voice warning;
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 29
(iii) Red signal lamp of respective compartment comes 'ON' in fire
extinguishing system panel;
(iv) Flight data recorder receives signal of 'FIRE';
(v) Cockpit voice recorder receives signal of 'FIRE';
(d) Fire Extinguishing Process : Two balloons (filled with freon) each of 4 litre capacity are placed in the
MGB compartment for fire extinguishing purposes. One balloon is for
automatic release and the second balloon is for manual release.
When the fire warning system sends a signal of "Fire in ......compartment", simultaneously the
channel of that compartment is opened from the balloon for automatic release. If necessary, the flight
engineer then depresses the button for manual release of 2nd balloon.
The helicopter 9N-AHJ impacted terrain 2 minutes 58 seconds after take-off. So the APU would
have been switched off at that time because normally the APU is switched off before take off or just after
take-off.
The accident took place on 23rd September, at around 10:48 LT. Normally at an altitude of 3200
m. at this time of day and month, the outside air temperature is around 11ºC. At this outside air
temperature the kerosene heater is normally not used. Kerosene heaters are normally used when
temperature is below 3ºC.
So, possibility of 'FIRE' signal from "MGB and APU compartment", or "Kerosene Heater
Compartment" is very remote. Therefore the 'FIRE' signal registered by the FDR was possibly from
either "one of the engine compartments' or "both engine compartments" upon impact.
As the helicopter 9N-AHJ with a take-off weight of 10,344 kg faced first impact, the nose landing
gear was detached and frames were also deformed and damaged due to the high impact. Such a huge
impact can easily disturb and damage the engine attachments with the airframe and engine modules e.g.
combustion chamber, free turbine. In case of damage to engine supports around the combustion chamber
or free turbine (4th or 5th support) and damage in compressor turbine blades or free turbine blades can
cause the ejection of flame from the combustion chamber to the compartment and to outside of the engine
compartment.
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 30
Regarding the wreckage analysis, the central part of fuselage from 1st frame to 11th frame was
totally burnt and the helicopter had toppled and was resting on its left side with left external fuel tank
(≈400 liter fuel) below the engines and right external fuel tank (≈400 liter fuel) above the engines.
Engines are attached with the 2nd frame and its location is up to the 7th frame of central part of fuselage.
Hence, 'Fire' in helicopter was started simultaneously upon impact with terrain and most probably from
engines with fuel poured from external fuel tanks with the helicopter in an inclined position. The
helicopter was extensively burnt resulting in most of its parts in the condition of ashes or in a melted
down condition.
The accident site is at an altitude of 3990 m. in remote mountainous area and inaccessible to the
ordinary people. Therefore Fire Fighting Services was not possible at the time of accident.
1.15 Survival Aspect
Survival Aspects: This was an un-survivable accident as seen by the extent of injuries and mutilations
inflicted on the occupants. The death must have been instantaneous. The burn and charring was post-
mortem. There was no smoke or combustion in the trachea in some bodies where it was looked into.
1.16 Examination of Helicopter Components:
The accident of the helicopter 9N-AHJ took place in a mountainous area of an elevation of 3990
m. The status of the several components were found as below:
Engines : The helicopter was equipped with two TV3-117VM engines. Both engines were
burnt completely. So no functional or any test/examination could be possible. As
per FDR read out analysis, both engines functioned normally till the impact.
Main Gearbox : The helicopter was equipped with VR-14 gearbox. The gearbox was found totally
burnt. So no test of this component was possible. As per FDR report, the function of
Main Gearbox till the accident was normal.
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 31
FDR : The helicopter was equipped with Digital Flight Data Recorder type 'SDK-8', which
was recovered and read out.
CVR : As per aircraft document the helicopter was equipped with CVR type P-503B but it
could not be found after several search attempts. So, CVR information could not be
obtained.
Autopilot System : The helicopter was equipped with AP-34 type autopilot System. Components of the
system were not identified as most of them were completely burnt. However, no
evidence was found to indicate that there were any problems in autopilot system.
1.17 Additional Information
Eyewitnesses at Ghunsa, the organizing charter party, search and rescue workers, maintenance
engineers, friends of pilots, persons familiar with the crew of the helicopter, CAAN personnel, media
persons and forensic specialist etc. were invterviewed in the process of investigation. Photos and video
materials related to the accident were also collected from different organizations and analyzed. The
Commission also interacted with ICAO study team on aviation safety led by Capt. Roger Mulberge from
Asia Pacific Office, Bangkok.
1.18 Organization and Management Information
Present Shree Airlines was registered on 2055/10/07 B.S. in Nepal as Air Ananya Pvt. Ltd. for the
purpose of operation domestic air service in Nepal. Its head office is located in Tripureshwor in
Kathmandu. It started its operation on 2056/01/04 B.S. with MI-8 MTV 1 and MI-8 AMT helicopters.
Company changed its name as Shree Airlines Pvt. Ltd. on 2059/11/30 B.S. Presently company has 3 such
helicopters.
2. Analysis 2.1 Introduction
Final Report of Accident Investigation of helicopter 9N-AHJ
Page No. 32
The analysis of the event that led to the accident of helicopter 9N-AHJ began with a brief
summary of the factual evidence gathered during the investigation. Finding the cause of the accident is
usually a deduction from known set of facts. Discussions were held about the violation of regulation with
conducting IFR flight with VFR certified helicopter in unfamiliar terrain without proper flight planning
which could lead to the probable cause of the accident.
2.2 Methodology The following methodologies were employed to find out the probable cause(s) of the accident of
MI-8MTV-1 helicopter 9N-AHJ of Shree Airlines :
(a) Accident Site Visit :
This accident took place in mountainous terrain with steep rugged cliff at 3990 m at Lelep
V.D.C-9, Faledanda of Taplejung. The accident site could be reached only by the professional
climbers using mountaineering climbing equipments. The members of the Commission
visited the Ghunsa helipad and studied the route followed by helicopter 9N-AHJ. Due to
inaccessibleness of crash site, members of committee inspected the site by air. The wreckage
distribution area and position of wreckage were also observed.
For proper analysis of the site and wreckage, photographs and video materials taken by the
rescue team members (professional climber of Nepal Mountaineering Association) were
collected by the Commission.
(b) Interview and Statements :
Flight crew flying that area, local witness of Ghunsa and Taplejung were interviewed. Search
and rescue team, representative of WWF, ATC officer of Taplejung, forensic specialist were
also interviewed to gather information of helicopter, crew and passengers.
(c) Documents, Log Book and Records :
Aircraft logbooks, engine log books, component cards and helicopter journey logbook were
checked. Maintenance and modification records of helicopter were also studied. Pilot record,
flight records were also observed.
2.3 Mechanical and External Factors
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2.3.1 Incapacitation of Pilot
The pilots possessed good physical health. The crew didn't have any history of 'mental' illness.
The pilots flying records showed that both pilots were highly experienced. Thus possibility of
incapacitation of pilot had been ruled out.
2.3.2 Engine Failure :
The helicopter 9N-AHJ was equipped with two TV3-117VM engines with max power of 2200
SHP each. As per FDR analysis of 22nd and 23rd September 2006 flights of sectors Kathmandu-
Okhaldhunga-Fungling-Ghunsa and from Ghunsa to Fungling (accident recorded sector), both
engines were operating normally in all sectors. Until the impact of the helicopter, the engines
were functioning normally. Even after impact, the engines were operating for 1 min. 10 seconds.
Hence the possibility of the engine(s) failure is ruled out.
2.3.3 Failure of Helicopter System :
As per FDR read out, "Fire" was registered only after the impact of helicopter with terrain.
Hydraulic system failure was also not registered in the flight till impact as per the FDR read out
graph. Hence failure of helicopter systems e.g. fire, hydraulic, flight control, pneumatic can be
ruled out.
2.3.4 Tail Rotor/Transmission Failure :
In case of tail rotor failure or transmission shaft breakage during flight, the helicopter flight path
changes suddenly with rotation in its vertical axis and the pilot normally switches off the engines
following the failure. In this case as per the FDR read out graph, the engines were operating
normally till impact and the heading of the helicopter had not changed suddenly to show rotation
in its vertical axis. Hence the tail rotor or transmission failure is ruled out.
2.3.5 Major Components Failure :
No evidence of abnormality was found regarding loss of main rotor control as 'high vibration'
or "MGB oil low pressure" was not registered in that flight in FDR read out graph. Main rotor
RPM and longitudinal movement of swash plate shown in FDR read out indicates that major
component failure can be ruled out.
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2.3.6 Explosion in Flight :
In the case of an explosion in flight, wreckage is usually scattered in larger area. As per FDR
read out, all helicopter systems and engines were operating normally till the impact of
helicopter with terrain and all wreckages were concentrated in a limited area. Hence, the
explosion as the cause of accident can be ruled out.
2.3.7 Maintenance Lapses
The commission examined the maintenance history of the helicopter and found that all the
airworthiness directives and service bulletins had been complied with as per maintenance
requirements within the prescribed time frame. The technical logs and log books show that
the maintenance works, major inspection works and modifications were carried out as per
approved maintenance program or bulletins. No technical defects were found in technical
logbook prior to its flight.
2.3.8 Weather Condition :
The actual weather observation on 23 Sept. 2006 at Taplejung, Okhaldhunga and Biratnagar
at 0545 LT (0000 UTC) and 0845 LT (0300 UTC) was cloudy with rain. According to
eyewitnesses at Ghunsa, the weather at the time of departure of the helicopter in the morning
was cloudy with drizzle and the surrounding mountains were not completely visible.
Weather at Ghunsa was deteriorating due to the influence of the depression whose low
pressure centre was situated at Bihar, India. The eyewitnesses at Ghunsa told to the
commission that at the time of take-off of the helicopter the weather was very bad and within
few minutes the helicopter was disappeared into the clouds. Hence departure from unmanned
station to fly on high altitude with maximum take-off weight in such a bad weather is the
main contributing factor for this accident.
2.3.9 Flying over Unfamiliar Terrain
Ghunsa is situated in a very narrow valley at an altitude of 3145 m. All the surroundings are
high altitude mountains. Normally Ghunsa is a single approach helipad from south and for
departure pilot has to follow the Ghunsa river for south on completely VFR condition. This
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was the first time that Captain had been to Ghunsa and his Co-pilot was also not been there
for long period. So, they were not familiar with the terrain and its surrounding hills. The
possibilities of change of weather and wind patterns were not familiar to them. The pilot's
decision to enter clouds in the region where the terrain was unfamiliar to them was one of the
major contributing factors for the accident.
2.3.10 Violation of Regulation
MI-8MTV-1 Helicopter 9N-AHJ was certified for Visual Flights Rules (VFR) only. On that
day while being at Ghunsa, pilots were completely aware of surrounding weather. It was
completely covered up with low clouds having poor visibility. But pilot intentionally decided
to take-off and entered into the clouds just after the take-off clearly violating the Flight
Operations Regulation.
2.3.11 Crew Coordination
The weather of Ghunsa was not advisable for VFR flight. The Flight Engineer had already
started the APU (possibly under the instruction of Captain). As per eyewitnesses, Co-pilot and
cabin attendant were out of the helicopter at that time and later they entered to helicopter
when engines were already started as well as the passengers were on board.
Both pilots were of Captain status, so the trans-cockpit authority gradient was flat. This
situation could inhibit non-flying pilot interfering with or objecting flying captain's decision
or action, thus affecting crew coordination and communication adversely.
.
There is possibility that unhealthy relationship between Russian (foreign) crew and Nepalese
crew existed. Generally there appears to be an unhealthy working environment between
Russian crew (Captain and Flight Engineers) and Nepalese crew (mostly Co-pilots). the
Russian crew's intention is to delay the Nepalese pilots’ upgrading to Captain thus insuring
their jobs security whereas Nepalese would like to be assisted towards their career promotion
to Captain. So there is likelihood of not getting optimal communication and interaction
between the Russian crew and Nepalese crew.
So possibility of crew coordination regarding weather, pay load, surrounding obstacles, route
plan etc. prior to departure is very remote.
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2.3.12 Communication
As per communication log sheet, Taplejung Tower was not found 'watch on' on 22nd and 23rd
September 2006 at the time of flight. 9N-AHJ could not communicate its flight details to
Ghunsa and position report on VHF communication. So actual flight details and plan level
could not be logged in. But while flying on Fungling to Ghunsa leg, pilot had reported its
altitude and ETA Ghunsa and also 'on ground Ghunsa' on 5805.5 KHz to Bhojpur and
Kathmandu. But it failed to report its flight details and departure message to any station on
return leg.
2.3.13 Take-off weight
As per nomogram of flight manual, the take-off weight 10,344 kg from Ghunsa (H=3145 m,
OAT=11ºC) was within the limit. But this take-off weight to fly in bad weather in higher
altitude in narrow valley would not allow maximum rates of climb.
If pilot had judged its take-off weight and the surrounding weather, he should have to wait for
the improvement of weather. Hence the Commission is of the opinion that crew did not
analyze pay load regarding the weight of the take-off considering the possible high rate of
climb in such bad weather condition.
2.3.14 Inappropriate Decision
As per Flight Data analysis of Fungling-Ghunsa sector, it was found that helicopter conducted
flight from 1771 m (Fungling) then smoothly climbed to 3400m and landed at Ghunsa (3145
m). While flying from Fungling to Ghunsa, pilot was facing the overcast and drizzling
condition of Fungling but he started flight for high altitude helipad without analyzing the high
altitude weather condition. Also on way to Ghunsa, pilot didn't make proper operational plan
for his return leg in same route.
Just after departure from Ghunsa, the helicopter flew towards north and then to southerly
direction. It entered into clouds over the Ghunsa valley with a speed of 150km/hr. The Pilot
might have thought that he would be in VFR condition after crossing the valley but it turned
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out to be a wrong decision. The weather in such valleys during monsoon can change very
rapidly. This decision to enter cloud at this speed was inappropriate.
2.3.15 Hypoxia
a. As per the Company S.O.P. Manual flight crew are required to use oxygen above 4000 m or
13000 ft AMSL. Though mask headset with a communication cable of the flight crew is
fitted through tube with oxygen which are to be plugged to the oxygen port. However flight
crew do not plug in the oxygen tube during high altitude flights. According to ICAO and
CAAN Regulation flight crew member shall use breathing oxygen continuously above 3000
m if the flight above 3000 m amsl. In the Company Standard Operating Procedure (SOP)
Manual flight crew are required to inhale oxygen in altitude above 4000 m amsl.
b. The crew would not be using oxygen during this flight. This could cause hypoxia. Even with
mild degree of hypoxia, thinking may be dulled, judgment may be skewed, problem solving
abilities and normal motor skill may begin to fail and reflex reaction may slow down. To
make matters worse the flight crew are usually unaware of these failings and instead they can
become euphoric and over-confident.
c. At Ghunsa the helicopter had stayed at Ghunsa for nearly 45 minutes and then took off
climbing until it crashed at an altitude of 3990 m AMSL.
d. The hypoxia due to high altitude must have affected the flight crew on their thinking process,
judgment, problem solving abilities and normal motor skill and reflex reaction adversely.
2.3.16 Flight Analysis
The flight programme was from Ghunsa to Fungling on 23rd Sept. 2006. After departure time of 2
min. 58 seconds, helicopter faced impact at rocky mountain at 3990 m. This flight is analyzed in 3
phases :
(a) From take-off time to 2 min. 30 seconds.
The helicopter first hovered and took-off with translational lift to north and then to south. It entered
to cloud while leaving valley. The speed of helicopter was first increased upto 150 km/hr and then
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gradually decreased. The main rotor RPM was approximately 92% and engines power was in take-
off.
(b) Flight from 2 min. 30 seconds to 2 min. 45 seconds (flight with panic).
Crew observed from radio altimeter that they are only 60 m. above the ground in 2 min. 30 seconds
after departure from Ghunsa. They were flying in IMC condition and they were probably panic as
they felt that the peak was somewhere around them. This time they had 62 km/hr speed, 91% main
rotor RPM and 3885 m. elevation. Pilot decrease the speed and applied maximum power to achieve
high rate of climb. They reached to 4033 m. in 2 min. 45 seconds and air speed was 31 km/hr.
(c) Flight from 2 min. 45 seconds till impact (2min. 58 sec.)
Collective pitch was raised to its maximum to achieve maximum power causing maximum pitch
angle of main rotor blade. Which resulted drop in main rotor RPM to 90% and sometime 89% also.
The main rotor RPM in maximum power should be 92% to 94%. The air speed was only 31 km/hr
when helicopter was at 4033 m. Then helicopter started to sink due to combine effect of drop in air
speed, drop in main rotor RPM, helicopter weight and flying in IMC. Then helicopter descended
with rate 3 to 4 m/s and just before impact the air speed was 12 km/hr and main rotor RPM 90%.
2.3.17 Factors contributing to influence pilots to depart Ghunsa in bad weather
(a) The Daily Inspection (DI) of 9N-AHJ was carried out at 5 PM of 21st Sept. 2006. The validity
of the DI is for 48 hours. Therefore the validity would have expired at 5 PM on 23rd Sept. 2006.
The crew members may have intended to reach Kathmandu before the validity of the DI expired.
(b) Since Ghunsa is at an altitude of 10,700 ft. (above 10,000 ft.) it would not have been an
appropriate location to spend the night due to the high altitude that could adversely affect the
elderly passengers and due to the lack of comfortable lodges available for the dignitaries.
(c) Some of the foreign dignitaries had further programmes to Sauraha, Chitwan in the afternoon of
23rd Sept. 2006 and this information was passed to the crew members by WWF officials which
could have contributed to influencing the crew members to depart Ghunsa inspite of the
unfavorable weather.
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3. Conclusion
3.1. Findings
1. Weather condition of Fungling, Taplejung at the time of departure was cloudy with frequent
drizzle.
2. Weather condition of Ghunsa was cloudy with light rain. The visibility was poor and surrounding
hills were completely covered up except to the north where the visibility was slightly better.
3. Ghunsa helipad being an unmanned station, further details of weather and communication with
the helicopter was not possible.
4. This was the first flight of Capt. Kim to Ghunsa so he was not familiar with the terrain and its
surroundings.
5. 9N-AHJ had reported its position to Bhojpur and Kathmandu on HF while it was flying from
Fungling to Ghunsa. But it didn't call any station for the departure from Ghunsa to Fungling
6. Without analysing the weather condition, the helicopter took-off from Ghunsa and intentionally
entered into the cloud.
7. The helicopter was not certified for Instrument Flight Rules (IFR). So entering into cloud
intentionally in high mountainous area is not only the wrong judgment but also the violation of
Flight Operations Requirement (FOR).
8. After 2 min 58 seconds from take-off, the helicopter faced impact on steep rugged surface terrain
at the altitude of 3990 m. and immediately caught fire.
9. Pre-flight briefing and proper crew coordination among crew members were not found to be
followed.
10. Location of crash-site is a rocky steep cliff and ordinarily inaccessible.
11. Cockpit and passenger compartment of helicopter was completely burnt.
12. Though the take-off weight for the flight from Ghunsa was not out of limit, take-off from high
altitude helipad with high rate of climb in such bad weather condition late morning with
unpredictable wind condition was poor judgment on the part of crew members.
13. As per FDR report, the power plant and helicopter systems were functioning normally till the
impact.
14. As per helicopter documents, the helicopter was equipped with a Emergency Locator Transmitter
(ELT) but the signal of ELT was not received by any stations.
15. As per technical documents, all maintenance works were carried out as per Approved Schedule
Inspection Program and service Bulletins of designer.
16. Pilots were certified and qualified in accordance with present regulations.
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17. The flight crew were physically and mentally fit and had passed the medical assessment.
18. Flight crew were adequately rested and had normal breakfast in the morning.
19. It is not confirmed that the flight crew had used oxygen at Ghunsa and during flight.
20. There is no evidence of unlawful interference.
3.2. Causes
The Commission has concluded that the probable cause of the accident is the cumulative effect of
the followings :
a. Without analyzing the local weather condition, pilot took-off from Ghunsa helipad in poor
visibility and immediately disappeared into the cloud and continue flight in bad weather on IMC
condition violating the visual flight regulation in such weather.
b. This was first flight of Capt. Kim, so he was not familiar to the terrain around Ghunsa and local
weather condition mainly in rainy season.
c. Pilot could not maintain the normal rate of climb and speed after reaching to 4033 m. though the
engine power was maximum. The combined effect of low speed, low main rotor RPM, helicopter
weight at that altitude and flying into cloud (IMC) resulted the helicopter to sink and finally hit
the rocky cliff at 3990 m. The helicopter was severely damaged and burnt and all 4 crew
members and 20 passengers died in this accident.
d. Lack of crew coordination among the pilots and lack of situational awareness, pilot took-off from
Ghunsa and climb for high altitude and hypoxic effect.
4. Safety Recommendation
4.1 TO CAAN
1. Every pilot should take refresher training as per FOR. CAAN should ensure the effectiveness of
these trainings.
2. CAAN should ensure the installation and serviceability of FDR, CVR, ELT, GPS in aircrafts.
3. Most of the accidents occurred in Nepal were in monsoon seasons especially by flying IMC
condition by VFR certified aircrafts. To prevent this, CAAN should develop a format for daily
performance report of the pilot and circulate it to the airlines and make periodic audit.
4. CAAN should instruct the helicopter company to issue the supplement in their Operation Manual
to calculate the pay load with further safe margin rather than calculating from nomogram for
flight, in monsoon with possibility of high rate of climb over difficult terrain.
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5. On the basis of analysis, findings and recommendation of "serious incident" or "accident"
investigation reports, CAAN should conduct awareness programmes with the respective airlines
operating same type of aircraft.
6. FOR should include oxygen use in high altitude flights. CAAN should scrutinize the company
Flight Manual and SOP Manual and make uniform regulation regarding oxygen use in high
altitude flights.
4.2 TO Shree Airlines
1. Pilot should be aware of Standard Operation Procedure (SOP) and Operation Manual of their
company through an awareness program conducted by the concerned airline preferably every 3
months. This should include the followings:
(a) Flying in IMC by a helicopter certified for VFR should be strictly prohibited.
(b) Preflight planning by the crew should first be conducted on the ground at the place of origin
before undertaking any flight, which should cover the entire information regarding the
route, weather, altitude, terrain, obstacles and helipad characteristics specially those flights
to difficult helipads and the helipads where the crew members have never been before.
(c) Detailed study of concerned area map should be carried out and discussed among crew
members before take-off.
(d) The pay load of the helicopter during monsoon at high altitude helipads should be
calculated taking into consideration the possibility of high rate of climb and increase bank
angles in narrow valleys.
(e) Communication with stations to be established compulsorily prior to take-off, en-route and
landing.
(f) Engineer should be available for Daily Inspection of helicopter, if it is going to make night
stop other than the base for more than 24 hours.
2. Company should provide their pilots refresher classes of FOR, CRM, Meteorology and
technical/performance of helicopter by instructors authorized by CAAN.
3. Company should review their SOP for monsoon and high altitude flight and they should conduct
interaction programme for their pilots in every 3 months interval.
4. Operation Director, Chief Pilot and Safety Director should monitor the flight performance and
behaviour of their pilots regularly. If any pilot is found to conduct flight in IMC, it should be
investigated internally. Such a case should be taken as 'incident' and must be strictly discouraged.
Pilots should be encouraged to report in writing ‘near misses’ or ‘events’ or even ‘violation of
regulations and reason to do so’ without fear of having punitive actions from management.
5. Engineering and Quality Assurance Department should improve the documentation process and
validity of any inspection period should be strictly followed with.
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4.3 For all Concerns
(a) Aircraft certified for Visual Flight Rules (VFR) should not enter into cloud.
(b) Flight details before departure and landing report from unmanned airport/helipad should be
reported to the nearest airport.
(c) Flight at high altitude during monsoon and bad weather condition should be conducted by
experienced pilots familiar with terrain and weather condition.
(d) Meteorological Forecasting Division (MFD) at TIA provides weather forecast for next 24 hour
and mountain weather forecast in their web site www.mfd.gov.np with satellite image. Aircraft
flying high altitude helipads in monsoon and bad weather should be provided weather forecast
report by Airlines.
(e) The commanding pilots of domestic flights must get Met briefing from TIA Met Weather
Briefing especially during bad weather situation.
(f) Meteorological Office must be established in important aerodromes such as Lukla, Syangboche,
Taplejung, Jomsom and others for which CAAN should take initiative as required.
(g) Airline should regularly conduct CRM courses, dealing theoretical aspects and practical or role-
playing in various situations.
4.4 To the Ministry of Culture, Tourism and Civil Aviation
1. The Civil Aviation (Accident Investigation) Rules, 2024 B.S should be amended in the context of
open sky policy of the Government, the establishment of CAAN and the Nepali commitment in
the international forum.
2. The Rules should incorporate the formation of the Accident Investigation Commission, its
accountability, minimum qualifications of the members, compensation for their services, etc.
3. Expert Development Program should be initiated in the field of aeronautical engineering, aviation
security, aviation medicine, meteorology, air law and investigation techniques, etc. and a roster of
Accident Investigation Experts should be maintained in the Ministry.
4. Accident Investigation Management Unit should be established in the Ministry to monitor the
implementation of the Commissions’ recommendations and to maintain the archives.
5. As to conduct the Accident Investigation is the State obligation, instead of levying the cost to the
concerned operator, Ministry should provide logistics, budget and other essentials to the
Commission.
6. A clear national policy should be developed to regulate the helicopters certified to Cargo Version
for transporting revenue passengers to enhance their safety.