incident investigation report - uzpln

INCIDENT INVESTIGATION REPORT SUMMIT AIR’S L410 UVP-E20 AIRCRAFT (9N-AMG)

INCIDENT ON 22 MARCH 2020

CIVIL AVIATION AUTHORITY OF NEPAL (CAAN)

SUMMIT AIR L410 UVP E-20 (9N-AMG) INCIDENT INVESTIGATION REPORT 1

AIRCRAFT INCIDENT INVESTIGATION COMMITTEE

CIVIL AVIATION AUTHORITY OF NEPAL

FOREWORD

This report is prepared in accordance with the provisions of Civil Aviation Regulation Rule 83

(b) for the purpose of determining the cause of the incident and recommending safety measures

to prevent such kind of incidents in future.

The investigation committee has categorized this incident as a serious incident.

To find out the actual cause of the incident, the investigation committee used all the available

resources and evidences relevant to the incident investigation. This includes preliminary incident

report, technical information, scrutinizing of relevant aircraft documents, interviews with the

associated crew members and certifying staffs, CVR and FDR read out and analysis.

The sole objective of this investigation shall be the prevention of accidents and incidents. It is

not the purpose of this activity to apportion blame or liability.

Committee composition

Er. Bhesh Raj Subedi Capt. D.R. Nirola

Sr. Inspector (Airworthiness Expert) Sr. Flight Operations Inspector

Civil Aviation Authority of Nepal Flight Safety Standards Department

(Committee Coordinator) Civil Aviation Authority of Nepal

(Committee Member)

Er. Bidhan Shrestha Er. Samrat Pradhan

Dy. Manager Sr. Officer

Flight Safety Standards Department Flight Safety Standards Department

Civil Aviation Authority of Nepal Civil Aviation Authority of Nepal

(Committee Member) (Committee Member)

Date: 08 July 2020


Table of Contents

Abbreviations

Title

Synopsis

Page No.

1. Factual Information 9

1.1 History of the Flight 9

1.2 Injuries to persons 9

1.3 Damage to aircraft 9

1.4 Other damage 13

1.5 Personal Information 13

1.5.1 Pilot-in-Command 13

1.5.2 Co-pilot 14

1.6 Aircraft Information 15

1.6.1 General 15

1.6.2 Airframe details 15

1.6.3 Engine (Port) 15

1.6.4 Engine (Starboard) 16

1.6.5 Propeller (Port) 16

1.6.6 Propeller (Starboard) 16

1.7 Meteorological Information 16


1.8 Aids to navigation 16

1.9 Communications 16

1.10 Aerodrome information 17

1.11 Flight Recorders 17

1.12 Wreckage and impact information 17

1.13 Medical and pathological information 17

1.14 Fire 17

1.15 Survival aspects 17

1.16 Tests and Research 17

1.17 Organizational and management information 18

1.18 Additional information 18

1.19 Useful or effective investigation techniques 19

2. Analysis 20

3. Conclusions 24

4. Findings 25

5. Safety Recommendations 27

5.1 Summit Air Pvt. Ltd. 27

5.2 CAAN 28

Appendices

Abbreviations


A : Aeroplane

AEPPM : Aviation Enforcement Policy and Procedure Manual

AFM : Aircraft Flight Manual

AMSL : Above Mean Sea Level

AOC : Air Operator Certificate

ATC : Air Traffic Controller

ATPL : Air Transport Pilot License

CAAN : Civil Aviation Authority of Nepal

C/B : Circuit breaker

CG : Center of Gravity

CPL : Commercial Pilot License

CRM : Crew Resource Management

CVR : Cockpit Voice Recorder

DME : Distance Measuring Equipment

EOM : Engine Operation Manual

FC : Flight Cycles

FDR : Flight Data Recorder

FH : Flight Hours

FCU : Fuel Control Unit

FSSD : Flight Safety Standards Department

GE : General Electric

GPS : Global Positioning System


IAS : Indicated Airspeed

IFSD : In-Flight Shut Down

IP : Instructor Pilot

ITT : Interstage Turbine Temperature

Kg : Kilogram

KTM : Kathmandu

LH : Left Hand

LT : Local Time

METAR : Meteorological Terminal Aviation Routine Weather Report

MHZ : Megahertz

MoCTCA : Ministry of Culture, Tourism and Civil Aviation

MSN : Manufacturer Serial Number

MTOW : Maximum Take-off Weight

NG : Gas generator speed

P1 : Pilot in Command

Pax : Passenger

PCL : Propeller Control Lever

PIC : Pilot-in-Command

PPC : Pilot Proficiency Check

QRH : Quick Reference Handbook

RH : Right Hand

RTOW : Regulated Take-Off Weight

RWY : Runway


SCT : Scattered

SMS : Safety Management System

SOP : Standard Operating Procedure

TCAS : Traffic Collision and Avoidance System

TIA : Tribhuwan International Airport

TCL : Throttle Control Lever

TTSN : Total Time Since New

TSO : Time Since Overhaul

UTC : Coordinated Universal Time

VFR : Visual Flight Rules

VHF : Very High Frequency


Name of the operator Summit Air Pvt. Ltd.

Manufacturer Aircraft Industries a.s.

Model L410 UVP-E20

Nationality and Registration Marks 9N-AMG

Place of incident In-flight phase

Date of incident 22 March 2020


SYNOPSIS

Summit Air Pvt. Ltd. owned and operated LET410 UVP-E20 aircraft bearing the Nationality and

Registration Marks: 9N-AMG; MSN: 2912, Flight No. 301 encountered dual engine in-flight

shutdown during its flight from Kathmandu to Lukla on 22 March 2020. The crew diverted the

aircraft to Manthali airport, Ramechhap as it was the nearest one available and landed the aircraft

safely. There were 17 passengers and 3 crew members on board the aircraft.


1. FACTUAL INFORMATION

1.1 History of the flight

On 22nd March 2020, a LET 410 UVP-E20 aircraft owned and operated by Summit Air Pvt.

Ltd. bearing the Registration Mark: 9N-AMG, Flight No. 301 took off for Tenzing Hillary

Airport, Lukla from TIA, Kathmandu at 06:31 Local Time. The aircraft operation was a

scheduled passenger flight. There were 17 passengers and 3 crew members on board the

aircraft. It was its first flight of the day.

As per the PIC, the crew encountered severe vibrations coming from both the engines when

they were around 25-28 DME from Kathmandu at around 12000 feet. The vibration lasted

for approximately 6-8 seconds and resulted in severe pitch up and down movements. The

F/O informed the PIC that the left engine had suffered failure. The Captain upon inspection

realized that the right engine also had failed. There was no power lever response on both the

engines. The torque and oil pressure readings were zero in both the engines as per the PIC.

The crew diverted the aircraft to Ramechhap since it was the nearest one available and

landed the aircraft safely. There were no casualties.

1.2 Injuries to persons

Injuries Crew Passengers Others

Fatal - - -

Serious - - -

Uninjured 3 17 -

Total 3 17 -

1.3 Damage to aircraft

The aircraft was completely checked for damage during preliminary investigation. The

aircraft’s L/H elevator trim tab coupling was found dislodged upon inspection. The bolt and

nut had come off. The cotter pin was found broken and out of its position lying on the panel.

It is uncertain as to what may have led to the dislodging of the elevator trim coupling.

Additionally, the right elevator trim tab was also checked to confirm the status of the

attachment. The coupling rod was found intact.


Figure 1. Preliminary investigation of 9N-AMG


Figure 2. Left elevator trim tab attachment rod found dislodged during preliminary

investigation


Figure 3. The right elevator trim tab attachment rod which was found intact during

preliminary investigation


1.4 Other damage

No other damage to third party was found.

1.5 Personnel Information

1.5.1 Pilot-in-Command (PIC)

Gender Male

Date of Birth 17th June, 1968

Nationality Nepalese

CAAN licence Number ATPL-158 (A)

CAAN licence number validity 31-05-2022

Ratings L 410 UVP E-20

Total number of flying hours 13694 Hours

Total number of flying hours on

aircraft type (L410 UVP-E20)

462 Hours

Hours flown in last 7 days 11:10 Hours


Duty and rest time in the last 48 hours 20th March 2020- Flown 02:10 Hours 21st March 2020 Duty Off

Last CRM done on June 2019

Last PPC done on January 2020


1.5.2 Co-pilot

Gender Male

Date of Birth 30th November, 1986

Nationality Nepalese

CAAN license Number CPL-435 (A)

CAAN license Number validity February, 2023

Ratings L 410 UVP E-20

Total number of flying hours 2120 Hours

Total number of flying hours on

aircraft type (L410 UVP-E20)

966 Hours



Duty and rest time in the last 48 hours 20th & 21st March 2020 Duty Off

Last CRM done on May 2019

Last PPC done on January 2020


1.6 Aircraft information

1.6.1 General

1.6.2 Airframe details

Aircraft Type L410 UVP-E20

Aircraft MSN 2912

Registration Mark 9N-AMG

Manufacturer Aircraft Industries a.s.

Date of Manufacture 09 April 2014

Validity of C of A 04 March 2022

Name of owner and operator Summit Air Pvt. Ltd.

Aircraft Category Transport (Passenger)

Maximum Take-off Weight 6600 Kg

A/C TTSN 5104:46 FH

A/C Landings 7143 FC

Aircraft Last Weighing Date 29 December 2017

Aircraft Last Schedule Inspection/Check

done

P1 Check carried out on 12 March 2020.

1.6.3 Engine (Port)

Manufacturer GE Aviation

Engine Type GE-H80-200

Engine Serial No. 142010

Hours done (TSO) 1793:20 FH


1.6.4 Engine (Starboard)

Manufacturer GE Aviation

Engine Type GE-H80-200

Engine Serial No. 182006


1.6.5 Propeller (Port)

Manufacturer AV-725

Propeller Serial No 140020


1.6.6 Propeller (Starboard)

Manufacturer AV-725

Propeller Serial No 150028


1.7 Meteorological information

The en-route weather to Lukla and Ramechhap were fine.

1.8 Aids to navigation

The aircraft was equipped with all the required navigation instruments except TCAS.

There is no TCAS installed in this aircraft.

1.9 Communications

Communications at the time of the incident between the aircraft and ATC (Manthali

Airport Tower) were by VHF radio frequency.


1.10 Aerodrome information

Not applicable since the incident occurred during the flight phase.

1.11 Flight Recorders

The aircraft was equipped with Cockpit Voice Recorder (CVR) and Flight Data

Recorder (FDR). FDR was downloaded in-situ the aircraft in the day of incident. The

CVR was brought to Kathmandu and downloaded in the organization’s avionics shop

in the presence of CAAN investigation committee members. The committee

transcribed the CVR recordings. Summit Air provided the FDR analysis graph to the

committee for investigation purpose. Raw data from the FDR was extracted and sent

to Aircraft Industries a.s., Czech Republic for analysis. The CVR transcription and

FDR analysis graph are attached in the Appendix “E”.

Component Model Part Number Serial Number

Cockpit Voice Recorder FA 2100 2100-1020-02 000916450

Flight Data Recorder FA 2200 2202-2600-00 000905171

1.12 Wreckage and impact information

Not applicable.

1.13 Medical and Pathological information

Not carried out due to Covid-19 pandemic followed by complete lockdown of the

nation.

1.14 Fire

There was no pre or post-impact fire.

1.15 Survival aspects

All the passengers and crew members survived the incident. There was no casualty. The

passengers were evacuated safely from the aircraft with the help of cabin crew.

1.16 Tests and Research

Not applicable.


1.17 Organizational and management information

Summit Air Pvt. Ltd.

Summit Air Pvt. Ltd (formerly known as Goma Air Pvt. Ltd.) head office is located at

Muni Bhairav Marga, Subidhanagar, Kathmandu. It started its operation with two

"Cessna Grand Caravan 208 B" from February 24, 2011. Summit Air introduced brand

new LET 410 UVPE-20 (18 passenger seat) aircraft in October 2014 and extended its

operation to the other STOL airfields of Nepal being based in Kathmandu.

The Air Operator’s Certificate (AOC) valid on the date of the incident, was first issued by

Civil Aviation Authority of Nepal on October 11, 2010. As of the date of the incident,

Summit Air was operating scheduled and charter flights with 4 LET410 UVP-E20

aircrafts (including the incident aircraft).

The organization was issued with NCAR Part-145 approval certificate on 4 December

2014 and NCAR Part-M certificate on 7 Jan 2018 from CAA Nepal.

Civil Aviation Authority of Nepal (CAAN)

The Civil Aviation Authority of Nepal (CAAN) is a government organization established

to regulate the civil aviation activities in the country. The Flight Safety Standards

Department of CAAN is responsible for the safety oversight of airline operators and

conducts Airworthiness and Flight Operations audits in accordance with the audit

schedule. The divisions and sections under the FSSD are Airworthiness Inspection

Division, Flight Operations Section, Flight Standards and Licensing Division and

Recreational Aviation Section.

1.18 Additional information

Not applicable.

1.19 Useful or effective investigation techniques

The Captain, First Officer, maintenance manager and certifying staff were called for

questioning in line with the incident. They were handed down with the questionnaire

which is included in the “Appendix D”.

The committee decided to send the FDR and CVR data to the respective aircraft and

engine manufacturers to seek their assistance in the investigation. The committee


transcribed the CVR recordings for analysis purpose. The FDR raw data and CVR

recordings along with transcription were sent to the aircraft manufacturer (Aircraft

Industries a.s.) and engine manufacturer (GE Aviation) for necessary analysis and

investigation purpose.


2. ANALYSIS

The committee examined the following records of the operators.

1. Aircraft Technical Log Page (ATLP) of last 1 year (TLP No: C2040 dated 21.03.2019 to

TLP No: C3292 dated 21.03.2020).

2. Airframe logbook

3. Engine logbook

4. Propeller logbook

5. Aircraft Flight Manual

6. Normal / Emergency Checklist

7. Quick Reference Handbook (QRH)

8. Load and Trim sheet

9. Passenger and Cargo Manifest

10. Competency card of crew members

11. Flight and duty time limitation records of the crew members

12. Record of major maintenance work carried out in last 6 months before the incident date

13. Refresher / continuation training record of certifying staffs

14. List of applicable service bulletins and airworthiness directives

CVR analysis

In the CVR recordings, the vibration could be heard after approximately 22 seconds of

take-off. It lasted for approximately 6 seconds. The vibration was of mild nature. The co-

pilot had told the Captain about it to which the latter replied that the vibration was present

on earlier flights as well. However, upon examining the technical log page of the earlier

flights, there was no such snag entries done.

During the cruise phase i.e. 10 mins 11 seconds after take-off, severe vibration occurred

followed by engine failure. Initially the Co-pilot told the Captain that left engine had

failed. The Captain after checking the parameters told the Co-pilot that even the right

engine had failed. However, this cannot be confirmed in the CVR transcription.

FDR analysis

Detailed study of the FDR data revealed that in-flight engine shutdown occurred due to

the momentary fuel supply interruption to the engine. The main reason for the fuel supply

interruption could not be ascertained as there could be many possibilities. Severe

vibration of the aircraft could have caused the crews to panic and mishandle the aircraft


by not following the proper procedure mentioned in their Aircraft Flight Manual. The

vibration which was very severe in nature and that lasted for 6-8 secs approximately was

enough to puzzle and distract the crew as to what was really happening to the aircraft.

They assumed the vibration was coming from the engines due to which they opted to

reduce the power. Subsequent action by the crew members were not performed in

accordance with the procedures mentioned in their AFM.

The FDR raw data was sent to the Aircraft Industries a.s. The following parameters were

analyzed.

1. Aircraft speed

2. Autopilot signal

3. Minimum oil pressure signal

4. Propeller speed

5. Vertical acceleration

6. Altitude

7. Gas generator speed

8. Pitch and roll angles

9. TCL position

The following parameters were found not registered correctly. Altogether 12 parameters

were found wrong.

1. Torque LH – registered in the range between 106% to 107% 2. Torque RH – registered in the range between 104% to 109% 3. Rudder Surface Position – always from +20 to +22 degree 4. AIR/Ground – always “In Air” 5. Engine L Beta Range – always “IN BETA” 6. Engine R Beta Range – always “IN BETA” 7. Min Fuel Press L – always “Low Press” 8. Min Fuel Press R – always “Low Press” 9. Brake LH – always below zero (-4,5kp/cm2) 10. Brake RH – always below zero (-3,6kp/cm2) 11. Hydraulic Press Main – always below zero (-6,7kg/cm2) 12. Hydraulic Press Emergency – always below zero (-2,7kg/cm2)

FDR event analysis

During wind milling both propellers were at high 1400-1600 rpm because the propellers

were not in Feather position. There is a significant difference between Np in both

engines. The aircraft was gliding for approx. 200 seconds and dived approx. 6000 feet.


R/H 1st in-flight restart with dwell at Idle. Most likely restart in emergency mode. The

TCL was above idle and the engine stabilized at idle most likely because of emergency

mode was engaged.

L/H 1st in-flight restart with rapid acceleration to 100% Ng and immediate shut down.

L/H rapid acceleration to 100% likely from L/H in Governing mode and TCL above T/O.

The TCL was above idle and the engine did not stop in idle.

L/H 2nd in-flight restart with dwell at approximately 20% Ng. Engine was operating in

emergency mode and the slow acceleration is manually controlled.

L/H engine shut down followed by successful recovery. Most likely the engine was being

operated back in normal main circuit control.

Ng fluctuations in both engines and final R/H engine shut down. Most likely the engine

was being operated back in normal main circuit control.

Data analysis- CVR / FDR comparison

In the FDR analysis, both throttle control levers were not returned to IDLE. The FDR

data confirms the position above T/O position.

In the CVR analysis, P1 requested P2 to switch isolation valve OFF (not specified which

engine). But this action is not in accordance with the EOM – Emergency Practice, 6.

Emergency Circuit of the Fuel Control Unit Application as per the analysis done by GE

Aviation.

Both engines suffered uncommanded IFSD most likely caused by fuel interruption. The

engines were windmilling for approximately 3 minutes, where the aircraft lost altitude

and speed.

Continuous operation with no oil pressure could cause damage in the bearings due to

insufficient lubrication. The propeller speed indicates the propellers were not in feather

position (from 1900 RPM to 1600 RPM on R/H engine and 1400 RPM on L/H engine).

AFM Section III, Emergency Procedures – Flight with two engines inoperative request to

feather the propellers. The R/H engine was successfully started. The analysis indicates

that the start procedure was in an emergency mode and PCL was in forward position,

above T/O position. Fast Ng acceleration with no dwell at approximately 20% Ng could

produce GT blade thermal damage.


AFM, Section III A Abnormal Procedures, Use of Emergency Fuel Control Unit: TCL

lever must be in IDLE to engage the emergency mode. The L/H engine had a start

attempt followed by second IFSD. The analysis indicates that the start procedure was in

normal main circuit mode and the throttle in full forward position which is not following

the AFM instructions. This aggressive start is likely to cause higher ITT than allowed,

which most likely caused GT blades thermal damage. CVR confirms the discussion

regarding isolation valve during the fast acceleration event. It is not clear if the

emergency mode was engaged.

The L/H engine successfully started – slow start. The analysis indicates that the start

procedure was in emergency mode which is confirmed by FDR and CVR. The L/H

engine experienced one Ng rollback and successfully recovered. Analysis suggest that the

engine was operated in normal main circuit mode. As per EOM, Emergency Practices,

Section 6.5: In-flight transition from Emergency circuit to Main engine control circuit is

not allowed. Ng fast recoveries might cause higher ITT than allowed, which can cause

GT blades thermal damage. The R/H engine experienced a few Ng fluctuations and

finally shut down (lowest peak is 40% Ng) during approach. Ng fast recoveries might

cause higher ITT than allowed, which can cause GT blades thermal damage.


3. CONCLUSIONS

The most likely root cause for the dual engine in-flight shutdown is a sudden fuel

interruption event. The reason for such occurrence can be determined only after the

engines are completely stripped down and investigated in the engine manufacturer

facility or an authorized repair center or any other decision made by the engine

manufacturer owing to its accountability.


4. FINDINGS

i. As per the CVR readout, the PIC was aware of the vibration that existed on the

earlier flights but did not bother to inform the certifying staffs about it. There was

no technical entry made in the technical logbook.

ii. The organization has established SMS unit. However, the reporting culture is

found not implemented effectively. The PIC was found not to have reported the

aircraft vibration issue which was present in the previous flights to the concerned

department.

iii. Despite the F/O making him aware of the vibration on the incident day, the PIC

disregarded it and continued the flight.

iv. During the engine failure event, the crew did not act in accordance with the AFM

and produced significant reduction in aircraft speed and altitude thus endangering

the safety of aircraft and its occupants by putting them in a high risk zone. Both

the propellers were not in feathering position after in-flight shut-down which was

not in accordance with the procedure as per AFM.

v. L/H engine in-flight restart with rapid acceleration to 100% Ng and immediate

shut down most likely caused by improper use of the emergency mode and the

flight procedures, most likely damaging the GT blades.

vi. Slow acceleration in the second start of L/H engine was caused by manually

operating in the emergency mode.

vii. The gas generator speed (Ng) oscillations during landing most likely caused by

change from emergency mode to normal circuit mode and then operating in

normal main circuit mode with air contamination in the FCU. EOM does not

allow change from emergency mode to normal main circuit mode in-flight, which

is against the aircraft safety and procedure.

viii. When the crew decided to divert to Ramechhap, the PIC could not determine the

exact location of Ramechhap airport. Despite the co-pilot asking him frequently

about its position, the PIC could not identify Ramechhap location. The PIC was

completely disoriented due to severe panic.

ix. Reported losses of torque are not possible to confirm due to erroneous parameters

in the FDR.


x. The aircraft’s L/H elevator trim tab coupling was found dislodged upon

preliminary inspection. The cotter pin was found broken and out of its position

lying on the panel.

xi. There are altogether 12 parameters of FDR found registered not correctly.

xii. The organization was found not complying with the recommendation issued by

the Government of Nepal Aircraft Accident Investigation Commission of L410

UVP-E20; 9N-AMH aircraft which met with an accident on 14 April 2019 at

Lukla.


5. SAFETY RECOMMENDATIONS

5.1 Summit Air Pvt. Ltd.

a. The organization shall conduct basic technical and performance classes for the

involved flight crews under the supervision of CAAN Flight Operations

Inspector(s) before releasing the crew for normal flights.

b. The PIC should fly with IP for at least 300 hours before being released to fly

independently with line pilots. The concerned IP shall be accountable for any

occurrences on the part of the PIC after clearing him for normal flights till the

completion of 100 hours.

c. Both the pilots must undergo CRM class especially focusing on human factors and situational awareness.

d. The IP should give more emphasis on the standard use of SOP and must instruct

the pilots on the proper usage of checklist as per the situation. Such instruction

class shall be monitored by CAAN.

e. The organization shall ensure that any snag / abnormalities encountered in the

aircraft must be entered in the Aircraft Technical Log Page. The message should

be conveyed to the concerned department immediately for taking appropriate

action.

f. The organization shall comply with the recommendation issued by the

Government of Nepal Aircraft Accident Investigation Commission of L410 UVP-

E20; 9N-AMH aircraft which met with an accident on 14 April 2019 at Lukla.

The operator should carry out the modification of the FDR of all its L410 UVP-

E20 aircrafts within one year period.

g. The operator must carry out download, read-out, and analysis of FDR of its

aircrafts at every 3 months or 300 hours interval whichever comes earlier. This

should be defined in its Customized Maintenance Schedule.

h. The engines (S/N 142010 and S/N 182006) of 9N-AMG aircraft shall be sent to

the manufacturer or an authorized repair center for engine strip down and detailed

investigations or any other decisions made by the engine manufacturer owing to

its accountability. The operator shall submit the investigation report to CAAN.


i. The primary and secondary flight controls attachment checks for integrity &

security shall be done at every 100 hours instead of 1200 hours (P3 check). The

inspection interval must be amended in the operator’s Customized Maintenance

Schedule.

j. The organization shall conduct SMS classes emphasizing on reporting culture for

all the crew members including technical personnel for effective SMS

implementation.

5.2 Civil Aviation Authority of Nepal (CAAN)

a. CAAN should form an enforcement committee to take appropriate actions on the

involved crew members and company as per CAAN Aviation Enforcement Policy

and Procedure Manual (AEPPM) for the violation of the SOP, SMS and

Operations Manual. CAAN should ensure that the operator complies with the

recommendations issued by the enforcement committee prior to releasing the

flight crew for normal flights.

b. CAAN should issue a circular to all the aircraft operators regarding the concerned

IP being accountable for any occurrences on the part of the PIC after clearing

him/ her for normal flights until the completion of 100 hours.


APPENDIX A

Copy of Aircraft Technical Log

Page of the incident day


APPENDIX B

Copies of statements

• PIC

• Co-pilot

• Cabin crew


APPENDIX C

Copies of Load and Trim Sheet and

Passenger Manifest of the incident day

Copy of Aeronautical Service Log

Page of Manthali Airport, Ramechhap


APPENDIX D

Questionnaires of crew members,

Maintenance Manager and

Certifying Staff


APPENDIX E

CVR Transcription

&

FDR analysis graph


\ APPENDIX F

Dual engine IFSD Investigation

Report by GE Aviation Czech

Republic (Engine Manufacturer)

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