AIB: Accident Investigation Bureau; AMSL: Above Mean Sea Level; B3A: Bureau of Aircraft Accidents Achieves; CAA UK: Civil Aviation Authority of United Kingdom; CAAN: Civil Aviation Authority of Nepal; CFIT: Control Flight in Terrain; CRM: Crew Resource Management; DNA: Deoxyribonucleic Acid; EASA: European Aviation Safety Agency; EGPWS: Enhanced Ground Proximity Warning System; FAA: Federal Aviation Authority; FAR: Federal Aviation Regulations; FOD: Foreign Object Damage; HFACS: Human Factor Analysis and Classification System; IATAs’: International Air Transport Association; ICAO: International Civil Aviation Organization; NA: Nepal Airlines; NAC: Nepal Airline Corporation; RNAC: Royal Nepal Airline Corporation; SARPs: Standards and Recommended Practices; SMS: Safety Management System; STOL: Short Take-off and Landing; VFR: Visual Flight Rule; WBA: World Bird Strike Association

1P: Single-Engine Reciprocating; 1T: Single-Engine Turbopropeller; 2P: Twin-Engine Reciprocating; 2T: Twin-Engine Turbopropeller; 3+T: 3+ -Engine Turbopropeller; JT: Other Turbofan Transport Category; A320: A320-series, Turbofan Transport Category; A330: A330-Series, Turbofan Transport Category; A340: A340-Series, Turbofan Transport Category; AT45: AT45, 2-Engine, Turbopropeller; AT72: ATR72, 2-Engine, Turbopropeller; B712: B712 Turbofan; B737: B737-Series, Turbofan Transport Category; B757: B757-Series, Turbofan Transport Category; E170: Embraer A170, Turbofan Transport Category; E190: Embraer E190, Turbofan Transport Category; F100: F100 Turbofan; MD11: MD11, Turbofan Transport Category; MD80: MD80-Series, Turbofan Transport Category; MD90: MD90-series, Turbofan Transport Category RJ85: Avro Regional Jetlines 85, Turbofan Transport Category; SF34: SF340, 2-Engine Turbopropeller; MIL: military; HECO: Helicopter

Nepal, officially the Federal Democratic Republic of Nepal, is a landlocked central Himalayan country in South Asia. It has a population of 29 million and is the 93rd largest country by area. Bordering China in the north and India in the south, east and west, it is the largest sovereign Himalayan state, which is unique in Asia in that it combines its climate with large variety natural beauty, amazing flora-fauna, rich cultural, historical heritage and constant alternation of biotopes and many more [1].

As a landlocked nation, air transportation is the only means to link the country to the outside world. The vitality of air transport industry in the economic growth and development of a nation is more pronounced in today’s globalized world.

Civil Aviation Authority of Nepal (CAAN) was established on 31 December 1998 under Civil Aviation Act, 1996. Civil Aviation Authority of Nepal (CAAN) realizes that one of the key elements to maintaining the vitality of civil aviation’s is to ensure safe, secure, efficiently at the national, regional and international level. As a regulator of civil aviation activities in the country, CAAN has the responsibility of ensuring safety and promoting air transportation in the country Nepal. CAAN sets requirements based on the Standard and Recommended Practices (SARPs) stipulated in various Annexes to the convention of International Civil Aviation. Based on these requirements, air transport industry needs to deliver safe and quality services in their respective areas of operation while maintaining a high level of capacity and efficiently in their endeavours. It is also important to spotlight the state visit of ICAO Council President Mr. Roberto Kobeh Gonjalez to Nepal in 2012, which provided enough leverage for the state and CAAN in their initiatives towards segregating service provider functions from the regulatory regime of CAAN, strengthening safety oversight capability of the Regulator and reviewing the legal framework in the line with Chicago Conventions and other ICAO Regulations [2].

Men have started sharing sky with birds after the invention of aircrafts. This mutual sharing is prone to accidents. Although there are various other elements like hails, debris etc. but today majority of incidents caused by foreign object damage (FOD) is to be reported as bird strike. Although the size of bird is very small as compared to aircraft, but high speed of aircraft makes the bird strike event as a dangerous phenomenon. First record of bird strike was documented by Wright brothers, the inventors of aircraft. In 1912, bird strike claimed first human fatality when Cal Rogers crashed in to sea after hitting a gull and jamming aircraft flight controls. Since then such accidents are increasing due to in air traffic. These accidents have claimed many human lives along with monetary and material losses. From 1990 to 2013, in a period of 24 years, at least 66 aircraft and 26 lives have been lost in civil aviation due to bird strikes. Statistical indicates that 73% of all collision occurs near the ground below 500 ft. and 94% under 2500 ft., making the take-off and landing phases especially critical to bird strike [3,4].

Front facing components of aircraft are exposed to bird strike. These include windshield, random, wing leading edge, engines, forward fuselage, empennage, landing gear, propeller etc. Figure 1 shows vulnerability of aircraft components to bird strike according to data provided in [5]. Furthermore, 29% bird strikes for engine and 26% for wing cause damage making these areas of aircraft highly damaged due to bird strike. Due to dangerous consequences of bird strike, aviation authorities like Federal Aviation Administration (FAA) demand all forward-facing components of aircraft to have a certain level of resistance against bird strike. Some Federal Aviation Regulations (FAR) relating bird strike are listed in Table 1 [6].

Figure 1: Vulnerability of aircraft-components to bird strike.

Table 1: FAA bird strike requirements.

The subject of aircraft accidents and bird strike against aircraft is under discussion since the invention of aircraft in the field of Airworthiness and different regulators recognizing the importance of aviation accident investigations, has also established common basic obligations through various council directives.

Early 20^th century, safety has been a constant byword in aviation development [7]. Data published by the ICAO (International Civil Aviation Organization) show that the safety of aviation has substantially improved from 1945 onward [8]. In 2009, according to the International Association of Transport Airlines, the western-built hull-loss accident rate was one accident per 1.4 million flights.

However, with air traffic steadily increasing, accidents do happen, despite the best effort of regulators and industry. The investigation of accidents and the determination of the causes and contributing factors, as well as producing recommendations for preventing similar situations in the future, are essential elements in the process of continuous safety improvement. For this reason, among others, this transport mode retains a globally low accident rate [9-14].

To make flying safer, independent investigation into accidents is essential, as it is the surest way of identifying the causes of an accident and answering the fundamental question of what really happened and what can be done to prevent similar incidents in the future [15-17].

The investigation of civil aviation accidents was regulated internationally is the first instance by ICAO, through the existing Convention on International Civil Aviation signed in Chicago in 1944 guidance and its Annex 13 [18]. Since then, ICAO has produced manuals and guidance material to advise states on the conduct of aviation accident investigations: for example, ICAO documents 6920 [19] and 9756 [20], Circular 298 [21] and many others [22].

The regulation sets out the roles of European Aviation Safety Agency (EASA) in accident and incident investigations. EASA carries out, on behalf of the member states, the functions and tasks of the state of design, manufacture, and registry when related design approval, as specified in the Chicago Convention and its Annexes. Therefore EASA, in accordance with Annex 13 [18] to the Chicago Convention invited to participating safety investigation as well as national civil aviation authorities.

Bird strikes and aircraft collisions in Nepal have not been analysed in any previous studies. This study attempts to identify the existing finish reporting system and culture.

The aim of this research is to produce a complete research report data of bird strike against aircraft, aircraft accidents (types of Aircraft, Place of Accidents happened, and number of fatalities and survival occurred) in Nepal between the years 1946-2016. Along with this research analysis, the author suggested enhances safety measures to be taken by CAAN to reduce such problems from hull-losses of human lives, fatalities to aircraft, hull-losses of cost airlines industry.

The data was collected by reviewing different aviation regulators and council directive sources such as: International Civil Aviation Organization (ICAO), European Aviation Safety Agency (EASA), World Bird-Strike Association (WBA), Bureau of Aircraft Accidents Achieves (B3A), and Civil Aviation Authority of Nepal (CAAN) along with qualitative approach via articles, newspaper.

This paper is based on the elaboration of statistical data collected from above mentioned sources and research analysis done ensuring safe airways in Nepal. As regards of analysis, the current problem is that no reports exist for all accident of aircrafts, bird-strikes and where they do, not all the data has been filled in Nepal’s Airways Achieves. Significantly voids are noted in parts of the form referring to bird strikes data. We must understand that the reporter is always the commander (pilot in command).

Aircraft operation in Nepal can be categorized basically in four categories as follows:

(I) Schedule

a) International

b) Domestic

(AI) Non-schedule

(BI) Helicopter (IV) recreational

Nepal Airlines, a State-owned carrier, operates internationally with B757 and A320 aircraft. Himalaya Airlines, a joint venture with Tibet Airlines of China, is a new international airline operating with A320 aircraft. Buddha Air, a major contributor in domestic front, is operating its regional flights to Varanasi (India) from Kathmandu with ATR-72 aircraft.

Domestic airlines operate with ATR-72/42, Jet Stream, CRJ 200, MA-60 and B1900C/D fleet on trunk-routes connected domestic airports situated in the plain areas. Whereas, small turbo-prop aircrafts like DHC-6 300/400, DO-228, Y-12E, LET 410 operate mostly to STOL airfields situated in mountainous high-altitude areas, ranging from 8000-10,000 feet above mean sea level (AMSL).

Small single-engine aeroplanes C-208 B and PAC 750 XL operate passenger and cargo charter services mostly to and from remote airfields in the mountainous areas. Such aeroplanes are not authorized to operate scheduled flights.

Helicopters are mostly engaged in high altitudes rescue operations and also providing logistic support for needy trekkers and expeditions. Majority of helicopters operating in Nepal are AS350 series, BELL 206, AS332, MI-8 MTV/AMT, etc.

Recreational aviation is based in Pokhara, the most exotic tourist destination of Nepal. Small piston engine ultra-light aircraft are operating to support leisure tourism.

Aircraft operation in Nepal can be categorized basically in four categories as (1) Schedule, (2) Non-Schedule, (3) Helicopter, and (4) Recreational (Tables 1-5).

Table 2: Schedule international operation.

Table 3: Schedule domestic operation.

Table 4: Non-schedule domestic operation.

Table 5: Helicopters domestic operation.

This section of this research paper presents the results and interpretation of aircraft accident and bird-strikes occurred in Nepal between 1946-2016 year’s data analysed in this study. Among total of 50 airports of the country, including an international airport, 32 airports are in operations. Many airports in Nepal are lying either in the narrow valley of high mountain or on the top of hill with elevation ranging from 8,000 to 10,000 feet AMSL.

Small turbo-prop aeroplanes like DHC-6 300/400, Do-228 and single engine aeroplanes operate in these airfields flying through uneven terrain and narrow gorges. So, flying to these vulnerable STOL airfields in such a hostile environment is challenging in itself however controlled-safe flight is necessary to establish an adequate regulatory frame to allow the safe operation of these aircrafts. Accidents with hulllosses, hull-fatalities in number taking places in Nepal between 1946- 2016 years occurring from different national and international aircrafts are depicted bellows

Accidents of Nepalese turbo-prop multi-engine aeroplanes

There have been 37 serious accidents and incidents with hull losses fatalities of Nepalese registered turbo prop multi-engine Aeroplanes (14 different operator Company) of Nepal from year 1961-2016. Eleven operating company delivered fatal accidents results while three company’s turbo-prop multi-engine aeroplane tasted accidents with zero losses of human lives which is shown in Figure 1 and graph 2 respectively. The largest number of fatalities in time frame was between 1961-to-2016, i.e., Nepal Airlines records of accident took place and number of hull-losses fatality is highest with 65 in number, Tara Air records of accident took place only twice with hull-losses fatalities number 22 and 23 in 15/12/2010 and 24/02/2016 respectively i.e., 45 in total number of fatalities. Yeti Airlines and Agni Airlines maintained very close number of hull-losses fatalities i.e., 30 and 29 in number respectively. Similarly, Everest Air and Shangri-La Air both air fatality 18 in number while Buddha Air, Sita Air and Necon Air 20, 19 and 15 fatalities in number as shown in Figure 2 respectively (Tables 6-13).

Figure 2: Accidents with hull-losses 1961-2016 (37 incidents).

Table 6: Recreational domestic operation.

Table 7: Accidents of Nepalese registered turbo-prop multi-engine aeroplanes (Source: CAAN).

Table 8: Accident of Nepalese registered single-engine Aeroplanes (Source: CAAN annual report 2016).

Table 9: Accident of Nepalese registered helicopters (Source: CAAN).

Table 10: Ultralight aircraft accident (Source: CAAN).

Table 11: Foreign aircraft accident in Nepal (Source: CAAN).

Table 12: Aircraft accident/incident achieves of Nepal (Source: ICAO, EASA, FAA, B3A).

Table 13: Bird strikes in Nepal (Source 1: WBA, Nepal Newspaper Records, Online Web and Interviews).

Accident of Nepalese single-engine aeroplanes

An example of disorder, negligence and lack of responsibility is the accident cause in Nepal Airlines in operation of charter “single-engine” aeroplane approach leads highest number of accidents occurred in between 1975-to-1998 delivering fatal accident and incidents with fatal hull-fatalities of 16 in number, Necon Air accidents with hullfatalities 5 with survival number 7, Air Kasthamandap accidents with hull-fatalities 2 and survival 9 and Makalu air accidents with zero hullfatalities in year 17/01/1999, 26/02/2016, and (21/11/2011-04/08/2016) respectively depicted in Figure 3.

Figure 3: Number of Hull-losses fatalities 1961-2016 (By 14 different turbo-prop multi-engine Airplanes).

Statistics shows that most aircraft accidents and incidents have occurred by Operator Nepal Airlines. Aircraft occurrence investigation agencies around the world estimate that 70~90% of accidents are due to non-adherence of procedure lack of training, bad decision-making and incorrect actions of personal involved in maintenance, operations or design of aircrafts [23-25].

Figure 4 statistic history proves above [23-25] and Nepal Airlines operator in Nepal is responsible for highest accidents and incidents by 11% in single-engine aeroplanes significantly reveals their human errors responsible of these accidents with hull-losses fatality number 16, and hull-losses fatality of Necon Air, Air Kasthamandap and Makalu air between 1975-2016 years is 5, 2 and 0 respectively.

Figure 4: Accidents with hull-losses 1975-2016 (7 incidents).

Accident of Nepalese registered helicopters

The research is aimed to investigate the causal relationship between human factor and aircraft accidents, incidents happening in Nepal.

A quick glance through the annals of Nepal’s aviation history of accident of Nepalese registered helicopters reveals a fairly large number of accidents (8 times between 1979-2016) have been recorded by Fishtail Air with hull-loses ranking second highest in number with 15 hulllosses fatalities. However, Shree Airlines statistics of aircraft accident records only two times (02/06/2005 and 23/09/2006) with highest number of hull-losses fatalities 24 which is shown in Figures 5 and 6. respectively. Incident without hull-losses taking place by operator like Himalayan Helicopter, Nepal Airways, Gorkha Airlines, Manakamna Airways, Air Ananya, Heli Hansa Services while helicopter operator/ owner like VVIP, Karnali Air, Asian Airlines, Simrik Air, Air Dynasty Heli Service, Manang Air and Mountain Helicopter recorded hull-losses fatalities number of 6, 1, 3, 2, 3, 1 and 4 respectively in the year between 1979-2016 depicted in Figures 5 and 6 respectively.

Figure 5: Number of Hull-losses fatalities 1975-2016 (By 4 different turboprop single-engine Airplanes).

Figure 6: Accidents with hull-losses 1979-2016 (31 incidents).

Ultralight aircraft accident

Recreational Aviation Nepal (RAN) could be centre for the aviation enthusiast. Indeed, recreational aviation can be focused based on most exotic tourist destination and can be key factors to support states, nation’s income along with can support leisure of tourism. Apparently, the risk associated with operation of recreational ultralight aircraft in Nepal will be comparatively higher along with hull-losses fatality number as well till regulator CAAN advised ultra-light aircraft operator until the operator adherence of procedures of enough training, technical-maintenance, responsible to achieve safe flight in weather and sabotage. The first ultralight aircraft accident was recorded in 3rd Oct 2013 with hull-losses fatalities number 2 and second accident in 10th Aug 2015 with hull-losses 2 missing records respectively. Thus, occurrences investigation ensures the risk associated with such operations of flights is higher (Figure 7).

Figure 7: Number of Hull-losses fatalities 1979-2016 (By 15 different Helicopters of Nepal).

Foreign aircraft accident in Nepal

Domestic aircraft movement are about to times more than international aircraft movements in Nepalese airports. According to the Civil Aviation Authority of Nepal (CAAN) annual reports analysis and classification of foreign incidence occurred by foreign airlines in Nepal between years 1955-2015 is tabulated in Table 10 as shown in above. The research analysis shows that Indian airlines faced twice accidents (in 15/05/1956 and 24/03/1958) in Nepal in with hull-losses of fatalities 34 in number, Kalinga Air, Thai Airways, Pakistan International Airlines (PIA), Lufthansa and Turkish Airlines with hull-losses 2, 113, 157, 5 and 0 fatalities in number shown in Figures 8 and 9 respectively.

Figure 8: Accidents with hull-losses 1955-2015 (7 incidents).

Figure 9: Number of Hull-losses fatalities 1955-2015 (By 6 different foreign aircrafts in Nepal).

In this study’s assessment period (1946 to 2016) data collected and analysed from aviation accidents investigation records through various council directives like International Civil Aviation Organization (ICAO) [26], European Aviation Safety Agency (EASA) [27], Bureau of Aircraft Accidents Achieves (B3A) [28] and various qualitative approach like online articles, newspaper, interviews etc. which is depicted in below Table 11. The results were expected to provide answer to research questions and tests of hypotheses that are raised in this study. The purpose of this study was to present analysis accidents/ incident results, precisely evaluate the trend of aircraft accidents/ incidents casualties in Nepal airspace. Attempt quantifying the role of investigation to state human errors in Civil Aviation Authority of Nepal (CAAN) contributes to aircraft accidents/incidents.

Formerly “Nepal Airlines Corporation (NAC)” known as the Royal Nepal Airlines Corporation (RNAC) which was established in 1^st July 1958 through enactment of Nepal Airlines Corporation Act 2019 with the intention to provide the air transportation service in Nepal, with one Douglas DC-3. It’s the government owned airways company and flagship airways of Nepal is symbolized heritage of the country. The name of the airlines changed from Royal Nepal Airlines to Nepal Airlines in 2006 after democracy movement, King Gyanendra Bir Bikram Shah agreed to relinquish sovereign power to the people [1,29]. Former name modified i.e., “Royal Nepal Airlines Corporation (RNAC)” into “Nepal Airlines (NA)” for the period 1946-2016 in Nepal accident archives database depicted in Table 11.

Civil aviation has a long-standing tradition of investigating accidents, which contributes to making aviation one of the safest forms of the transport. Table 11 presents the nature of accident occurrences within the study period (1946-2016). The result shows that the highest fatalities occurred from the Nepal Airlines (NA); 18 incidents recorded between 1946-2016 out of which 12 recorded as hull-losses fatalities maintaining 2nd highest number of hull-losses fatalities 136 in numbers. Similarly, Royal Nepalese Airforce recorded 7 incidents out of 5 categorized as hull-losses fatalities with 66 in number which is shown in above Figures 10 and 11. Moreover, international airlines companies like Pakistan International Airlines (PIA), Thai Airlines, Indian Airlines, and Hinduja Cargo took accidents with hull losses taking place between 1946-2016 with 167, 114, 35, and 5 hull-losses fatalities in numbers are listed in Table 11, Figures 10 and 11 respectively. Up to 5 aviation accidents were recorded in 1999 with hull-losses fatality 35 in number consecutively 1992 been the highest hull-losses fatalities in the history of Nepal aircraft accident 4 times incidents recorded with fatalities 280 in number. Yeti Airlines (domestic aircraft) maintains 3rd numbers of accident occurrences aircraft recorded in Nepal airspace. The results generally show absence of serious incidents and incident between 1946-to-1960. This might be due to the fact aircraft number in those years in Nepal was rare in number also due to the fact that data for this period were unavailable, but didn’t mean that there were no serious incidents or accidents. Lack of effective documentation before the inception of CAAN is the likely attributable reason (Figures 12-22).

Figure 10: Accidents with hull-losses 1946-2016 (61 incidents by National and International Aircraft in Nepal).

Figure 11: Number of Hull-losses fatalities between 1946-2016 (By 22 national and international aircrafts in Nepal).

Figure 12: July 31, 1992 Airbus A310 Thai Airlines (Fatalities Number 113)

Figure 13: Sep 28, 1992 PIA (Fatalities Number 167).

Figure 14: 17th Jan 1995 NA (Fatalities No 2;1 Crew+1 Passenger).

Figure 15: Sep 5th 1999: Necon Air (Fatalities No 15”5 Crew member+10 Passenger”.

Figure 16: 28th Sep 2012: Sita Air (Fatalities No. 19) known as UK Dead Remembered.

Figure 17: 25th May 2004 (Fatalities No.3 Crew Member).

Figure 18: 8th Oct 2008 Yeti Airlines (Fatalities No.18).

Figure 19: 24th Aug 2010 Agni Air (Fatality No. 14).

Figure 20: 16th Dec 2010 Tara Air (Fatality No. All Bhutanese Tourist 14).

Figure 21: 25th Sep 2011 Buddha Air (Fatality No. 19).

Figure 22: 14th May 2012 Agni Air (Fatality No. 16 including 3 Crew members) (*Note Source (Fig.12-22): Interview Footage of Nepal Television [34] and National Newspapers of Nepal [35,36].

It is estimated that fatal birds strike only occur once in a billion flying hours [30]. It can also be misleading to think that strikes with large birds would always be the most dangerous ones. Even a flock of small birds can easily break an engine, windshield or another aircraft structure shown in Figure 1 Vulnerability of aircraft component to bird strikes provided in [5]. The size of the birds doesn’t directly correlate with the damage sustained either. In fact, mass density varies a lot according to bird species. To give an example, a Laughing Gull (Leucophaeus atricilla) is about 1/3 of the size of a Herring Gull (Larus argentatus), but has significantly higher density. Another interesting example is the Starling (Sturnus vulgaris). They have a 27% higher mass density than gull and can form flocks with up to 100,000 birds. This is why Starling are sometimes called “feathered bullets” [3,4].

In Nepal, bird strike reporting is not a part of the mandatory incident reporting system, but it is strongly recommended by the Finnish Transport Safety Agency. The rules on whether bird strike reporting is voluntary, or mandatory vary in different countries. For example, the United States have a voluntary reporting system, but in Great Britain, bird strike reporting has been mandatory since the year 2004. In fact, on the 1st of January 2008, the CAA UK introduced a new system for reporting bird strikes online [31].

Bird strikes may obviously happen to any kind of aircraft with any kind of engine. Nevertheless, a more precise analysis reveals that bird strike reported at finished reporting data in this study assessment period (1946 to 2016) data collected and analysed from aviation accidents investigation records through various council directives like ICAO, EASA, B3A, FAA, WBA [26-28,32,33] and various qualitative approach like online articles, newspaper, interviews etc. have received from regulator CAAN which is depicted in below Table 12.

The trend assessment of bird strike against aircraft incidents and casualties in this study confirms that the CAAN need to be practice significantly improved in the sense the documentations of bird strikes and casualty data.

This became obvious regarding the appropriate classification and documentation of aircraft mishaps such as serious incidents. The Table 12 shows that only 6 accidents of aircraft documentation found, the improvements consisted of the deliberate effort by CAAN to collate and document as much as possible accident due to bird strike data that occurred even before it’s establishment. Hence, the accident/ accident date shown in Table 12 showed improvements in data records investigation need to be done by CAAN. In spite of this all incidents results in casualties, the relation between the number of accidents and the number of resultant casualties are not correlated due to the number of persons that may be involved in a particular accident [34-36].

In this section author attempted collecting aircraft horrific accident (data from National News Channel, National Newspaper of Nepal, Interviews etc.) occurs in the Nepalese airspace, and analysis indicate quantify human error involvement of CAAN framework to aircrafts accidents fully documentations accident reports. Also, the analysis state human error involvement in aviation operator was highest with decision errors as the most influential under the category of Unsafe Act of the Operators being the most casual factor, although all factors are to be considered a significant cause of concern. The historic horrific aircraft accidents occurred in Nepalese airspace is depicted below.

Air transport in Nepal can be considered in safest forms of travel with the improvements efforts of CAAN implementing new approaches to investigating accidents and incidents in civil aviation, as this is the key mechanism for preventing future accidents of aircrafts and birdstrikes. Being well aware of this fact, CAAN should be working on a regulation on the investigation and prevention of accidents to ensure efficient and independent inquiries into the cause of air accidents.

The regulation address organizational changes, improvements in the coordination between the authorities responsible for the technical investigation and judicial measures to protect the information obtained in the course of the investigation, improvements in the monitoring of safety recommendations, and the good governs/adopting of ICAO and EASA for each stage of the investigation of civil aviation accidents.

In line with ICAO and IATAs’ zero accident and zero fatality program, coupled with Annex 13 of the Chicago Convention, recommendations made to strengthen the function of AIB as well as collaborating agencies in the Nepalese aviation sector. It is hoped that these will be considered as tool for implementing safety recommendations issue by AIB of Nepal.

From the findings of this study, the following recommendations could be drawn:

1. The research study revealed that aircraft accident/incident data not yet improved even establishment of CAAN. This therefore calls for sustainable policy framework to enable the agency to maintain the peace of accident data collection, collation, storage and processing by CAAN.

2. In Nepal, funding is generally a major cause for concern, but funding AIB is immensely required to fully integrate the HFACS framework into use in Nepalese aviation sector, as this will provide adequate resources for specialized training, further research works on incident/accident preventing programs using the HFACS framework.

3. Human error involvement in commercial aviation was shown to be the highest with decision error under the category of Unsafe Act of the Operators being the most causal factor. It is therefore recommended that coupled with the current Safety Management System (SMS) being introduced into the aviation industry in Nepal; these will effectively minimize or prevent aircraft accidents/incidents in Nepalese airspace.

4. Review of CRM and the associated simulator training programs in order to enhance crew decisions especially in situations of abnormal performance. Also, the review crew pairing and scheduling policies in order to ensure a safe cockpit environment is advised.

Two major constraints were faced in the cause of undertaking this study. These constraints were mainly financial and consequently time factor. These challenges surmounted with the best of efforts required.

The enormous amount of financial resources required to fund this research was mainly experienced in the several months of engagement with the team on familiarization and categorization of final reports components on to the HFACS framework. Although the set objectives of the study were eventually met, but a deeper analytical approach would have been achieved had been more time.

Second crucial challenge was the issue of accessibility of accident data at the relevant departments and agencies of government involved. A hundred and one calls, and visits are required to the attention amidst their busy schedules). And third challenges were the issues of accessibility of bird-strike accident data: As Pilots are not familiar with bird species and often at the speed at which the strike occurred was such, that the reporter was unable to see or identify the bird species. Therefore, author experienced several months to find reports of bird strikes from national TV channels reporter, national newspaper articles etc., of Nepal. Nevertheless, problem might not appear if modern technologies, identification methods (feather identification, DNA etc.) have been introduced by CAAN in order to have correct data.

1. Further analysis not conducted in the work will be very useful in elucidating finer details such as understanding the five-year trend of human casual factor revealed by HFACS.

2. Application of a more sophisticated predictive models to determine the expected aircraft accident/incident trend in the Nepalese airspace.

3. Comparative analysis of findings within Nepalese airspace of likelihood of location dependent occurrences of aircraft accident.

4. Examination of the main primary and secondary safety measures in development countries and their effectiveness at enhancing safety.

5. An investigation into the constraints associated with aviation safety related issues in developing countries like Nepal in meeting ICAO standards and how these constraints can be reduced or eliminated.

Challenges of Aircraft operations in terms of safe flying emanate from various intersections of contributing factors. This entails considerations of various parameters which include aircraft type, size of fleet, flying environment associated with remote and trunk route destinations, human factors, etc.

1. CFIT: Major contributors to accidents

2. Hostile terrain and weather phenomenon

3. High altitude STOL operation

4. Unavailability of en-route weather information

5. Limitation associated with VFR operations

6. Accidents-turbo-prop aircrafts with ≤ 19 seats

1. CRM and CFIT reduction training

2. Installation of EGPWS and aircraft tracking system

3. Stringent pilot license requirements

4. Strict provision for visual flight rules (VFR)

5. Human factors training in aircraft maintenance

6. Safety awareness programmed

The authors wish to thank Dy. Director, CNS P & D Department Tribhuvan International Airport Modernization Project Er. Sanjeev Singh Kathayat of Civil Aviation Authority of Nepal (CAAN), Er. Khagendra Kumar Yadav (Himalaya Airlines), and Er. Parash Pokhrel (Shree Airlines) for their economic support of this investigation. My biggest appreciation goes to my family, I’m indebted for being my best family on the planet.