THE IMPACT OF AIR TRAFFIC CONTROL ON FLIGHT OPERATIONS IN NIGERIA

INTRODUCTION

Air Traffic control refers to a service provided for the purpose of giving instructions, information and/or advice that will enhance the safe, regular, and efficient con­duct of flights. This therefore im­plies that Air Traffic Control di­rectly determines the degree of safety, orderliness and efficiency with which flight operations are conducted. On the other hand, flight operations can be considered from two perspectives.

Firstly, flight operations can be defined as sim­ply the act of conducting the flight of an aircraft for a specific pur­pose.

Secondly, flight Operations can be considered as a combina­tion of activities (i.e. administra­tive, financial, operational and safety services), systematically provided towards achieving a safe and efficient conduct of flights. However, since ATC is provided to aircraft in flight or with the in­tension of flight, our analysis will therefore be carried out with the first definition of flight operations in mind.

TYPES OF FLIGHT OP­ERATIONS:

The extent to which Air Traf­fic Control affects the operations of an aircraft is determined by the type of flight being operated as well as where and how it is being operated. Flight operations can be classified into the following:

1.      Instrument or Visual Flight Operations

2.      Passenger, Cargo or Courier Flights

3.      Civil or Military Flight Opera­tions

4.      Controlled or Uncontrolled Flights

5.      Flight Training or Flight Test­ing Operations.

6.      Survey Flights.

7.      Agricultural Flights (Chemical Spraying)

8.      Business or Leisure Flights

9.      Search And Rescue Flight Op­erations

10.  VIP Flights

11.  International or Domestic Flights.

12.  Ambulance Flights or Do­mestic Flights.

13.  Navaids Calibration Flights

14.  Security or Fire Fighting Flight Operations.

15.  Political Campaign Flights

16.  Scheduled, Non-Scheduled or General Aviation Flights

BASIC IMPACT OF ATC ON FLIGHT OPERATIONS

The significance, relevance or necessity of Air Traffic Con­trol can be estimated based on the effect it has on flight operations as enumerated below:

Safety Impact of ATC on Flight Operations

The primary responsibility of an Air Traffic Control Unit is to prevent collision between aircraft as well as between aircraft and nay obstructions within the oper­ating vicinity of the aircraft. To this extent, the responsibility for the safe conduct of the flight of an aircraft shall be assumed by an ATC unit for all flights under her jurisdiction or in contact with her, until safely landed or handed over to another unit. Therefore such responsible ATC unit shall apply all relevant standards, procedures or techniques in effecting the re­quired vertical, longitudinal or lat­eral separation between aircraft in flight to ensure air safety.

Also Radar equipped ATC units are charged with the respon­sibility of providing surveillance services to aircraft operating within their jurisdiction thereby further enhancing the safety of such flights. In addition, and ATC Unit shall whenever necessary or possible:

1.      Provide arriving aircraft with relevant information regard­ing the status of the aerodrome
surface area and its associated fa­cilities.

2.      Provide arriving or de­ parting flights with aerodrome weather conditions and prevailing weather conditions on the Ap­proach path or Take-off climb area; as well as enroute weather forecast where such is likely to affect the stability and conse­quently safety of such flight.

3.      Assist all flights under her control whenever she has reason to become apprehensive or uncertain about their safety, by alert­ing all the necessary safety ser­vices or Rescue coordination cen­tres.

4.      Give preference in the handling of an aircraft under-go­ing an emergency situation to minimise lost of life and property.

5.      Assisting relevant secu­rity agencies regarding any aircraft which is known to be the subject of unlawful interference e.g. hi­jacking.

FINANCIAL IMPACT OF ATC ONFLIGHT OPERATIONS

Over 90% of flight operations in Nigeria arc with the aim of maximising profit. Thus, Air Traffic Control service is pro­vided with a high sense of effi­ciency or expeditiousness in ad­dition to safety. Flight operations is not only risky, but equally a very sensitive and expensive ven­ture. It is therefore the objective of every aircraft operator to minimise cost by conducting flights using the most optimum procedures or routes possible. However, this objective can not be fully achieved independent of air traffic control considerations. To this extent, ATC instructions or clearances are given with the highest degree of flexibility pos­sible, to allow for alternative course of action. The high rate of fuel consumption of most modern day aircraft and its attrib­utable cost makes time of es­sence in flight operations. The following are however some of the vital areas of cost implication for flight operations that concern ATC:

1.      Traffic Delays - This is one area that the ATC authori­ties are daily striving to improve on. Traffic delays can be caused by traffic congestion; VIP move­ment; emergency situation; inad­equate Air Traffic management manpower or systems; failure flow control, etc. All these have serve cost consequences on flight operations.

2.      ATS Route Network - Where ATS routes or Airways de­signed for channeling the flow of air traffic are not available or available but poorly equipped or inefficiently designed; can result
in increase flight time and conse­quently high cost of flight opera­tions.

3.      Flight Cancellation and Diversions - Flight cancellation or diversions causes severe setbacks in flight operations in term of cost and lost of customers. Cancellations or diversions that are of concern to ATC here in­clude those necessitated by fail­ure of ATMs or essential aero­drome facilities; emergency situ­ations, closure of aerodrome; traffic flow control etc.

4.      Aircraft Accidents of In­cidents   - This involves any oc­currence affecting the safety of an aircraft or related life and property that can be traceable to ATC, failure, negligence of inad­equacies.

5.      Requirement for Airborne Equipment - Changes in ATC pro­cedures, facilities or Navigational
aids can necessitate the acquisi­tion of new avionics or airborne equipment as well as flight crew
retraining with high cost implica­tions for airliners.

6.      En-route Navigational Charges - The relevant ATC au­thority (NAMA) charges a com­mercial values for the services it renders to user of her services of facilities. These charges are in accordance with ICAO guidelines and subject to periodic review. These charges equally translate into op­erating cost for flight operators.

OPERATIONAL IMPACT OF ATC ON FLIGHT OPERA­TIONS

For the purpose enhanc­ing the provision of Air Traffic control service, search and Res­cue as well as coordination of air­craft movement, all intending flights are required by law to no­tify the appropriate ATS of ATC Unit prior to operating an intended flight. This can be done either by radio or through a filed or stored flight plan which must be submit­ted to the relevant ATS unit at least 30 minutes prior to estimated time of Departure so as to facilitate ex­peditions departure. Also, flight scheduling can be subjected to ATC approval with regard to pre­vailing traffic situations at the pro­posed times and places.

Flight Operations into, out of, or across certain airspaces or aerodromes are determined by air­space classifications in accor­dance with types of flights or air traffic service available therein. For example, certain areas may be designated as "Restricted" or "Pro­hibited" areas as well as training areas or military flight Zones. ATC therefore remains responsible for guiding flights away from such ar­eas or within them in accordance with stated provisions.

The prescribed hours of operation of aerodromes as speci­fied by the relevant ATS Unit, can also affect flight operations into and out of such aerodromes. And also, when traffic per­mits, ATC relays flight regularity messages and operational mes­sages to operators from aircraft in flight, and vice-visa. The Operations of aircraft into and out of aerodromes is sub­ject to the provisions of the State Weather Minima which is pre­scribed by the relevant ATS au­thority and administered by the controlling ATC units at such aerodromes. This has a significant effect since it determines permis­sible weather conditions under which flights can operate at every aerodrome. The allocation is also sub­ject to approval by the relevant ATS authority.

STRATEGIC OR REGULA­TORY IMPACT OF ATC ON FLIGHT OPERATIONS.

The strategic impact that Air Traffic Control effects on flight operations refers to either policy measures, tactical or local mea­sures formulated and implemented by ATC authorities towards en­couraging or discouraging specific flight operations. Below are some of these strategies which ATC can implement with a profound impact on flight movement:

Traffic flow Control: This refers to a deliberate action aimed at regulating or minimising the
flow of air traffic into or out of a particular airspace in accordance with the capacity of the ATMs. The strategy is generally adopted to en­able ATC cope with minimal traf­fic at periods such as strike peri­ods, failure of ATC systems, fail­ure of Navaids; emergency peri­ods, ATC cadet training; or where one out of two or more runways is temporarily out of use.

Airspace Classification: Airspace classification is the categorisation of ATS airspaces in
accordance with the type of Air Traffic Service available therein. Thus where an airspace is classi­fied as "class A" e.g. Lagos UTA, it implies the permission of Instru­ment Flight Rules (1FR) Operations with the preclusion of visual flight rules (VFR) Operations. On the other hand, "Class B" airspace permits both VFR and IFR opera­tions. In addition classes C, D and E permit military flight operations in addition to VFR and IFR flights. Therefore such classifica­tions can be used as a strategy towards determining the types of flights that can operate in certain areas.

Establishment of ATS Routes, Airways SIDs, and STARS: The relevant ATS author­ity can establish new ATS routes or Airways as a strategy towards minimising total flight time or en­hancing free flow of flights. Like­wise, the designing of standard Instrument Departure Routes and Standard Arrivals routes within an aerodrome, might be with a de­liberate intension of enhancing Take-off climb and increasing the rate of landings respectively.

Reduction of Separation Minima: This strategy is being pursued vig­orously in Europe as a means of decongesting busy routes by re­ducing the minimum vertical separation minima to 1000ft for flights operating between FL330 and FL410 instead of the standard minima of 200ft.

Speed Limits: Speed limi­tations can be prescribed for flight operations at certain levels within designated areas as a means of regulating flight move­ment within an airspace that has
a high volume of medium of low speed fliers.

Requirement of Avionics on Board: This is a strategy that requires the carriage of specific
airborne equipment prior to oper­ating into certain areas to enhance the provision of Air Traffic Con­trol and air safety in general. For instance aircraft operating into or put of a particular airspace may be required to operate one or more of the following avionics components: ACAS (I, II, III); GPS: GNSS; INS, Radar mode A, C, or S etc. Presently, no such requirement exists in Nigeria ex­cept equipment.

Local Air Traffic Control

Instructions: These are a set of local instructions, procedures or guidelines complied by the rel­evant ATC authority to be adhered to by aircraft operating within a particular aerodrome, in accor­dance with its unique features or configuration. For example all de­parting flights might be required to climb to a specified height af­ter take-off before turning on course to avoid a notified ob­struction within the vicinity.

ENHANCEMENT OF ATC ON FLIGHT OPERATRIONS

Aerodrome Layout:

Most airports in Nigeria do not have Rapid Exit Turn Off or Runway End Taxiway Links. This defi­ciency compels landing and de­parting aircraft to use the Run­way for taxing or making 180° back-track thereby increasing run­way occupancy time which con­sequently leads to avoidable flight delays. Therefore the Federal Air­ports Authority of Nigeria (FAAN) should be encouraged to urgently undertake the restructuring of such aerodromes to enhance ex­peditious surface movement. Also, such restructuring should include runway lengths and widths expansion to accommo­date bigger aircraft in line with global changes.

It is commendable to note that the Federal Government through FAAN, has embarked on the expansion of the Yola Airport while a similar project is being planned for Calabar Airport.

Approach and Landing Aids: The high cost of flight di­version or bad weather related air­craft accidents, has contributed greatly to severe setback or dis­tress the airline industry is cur­rently going through. However, some of these occurrences would have been averted if the required aids were available and functional. Therefore to enhance the provi­sion of Air Traffic control service, and to achieve efficient conduct of flights; the reactivation of unserviceable and to achieve efficient conduct of flights; the reactivation of un­serviceable approach and landing aids should be encouraged while the installation of new ones where necessary, be embarked upon. It is also encouraging to note that the NAMA management is purs­ing this aspect seriously as instal­lation of DVVORS, ILS and NDBHs is currently going on na­tion-wide with the exercise hav­ing been concluded in airports like Lagos, Abuja, Kano, Port Harcourt, Jos etc. However, the Federal Airport Authority of Nigeria should urgently com­mence the rehabilitation of visual aids such as VASIS, PA/M, so­dium High Intensity Lighting sys­tems and precision Approach Lighting Systems which are ei­ther not available or unserviceable in most airports. These aids are very essential as they can im­mensely minimise flight diver­sions, delays or cancellations or even air disasters in bad weather conditions.

It is unbelievable that an aviation nation like Nigeria with a vast and strategic airspace as well as a considerable by a functional ATC Radar system. Even though ATC initially provided radar ser­vices at Lagos, Kano, Port Harcourt, Abuja, Kaduna and Enugu airports, all these facilities are presently not only unservice­able but totally obsolete. It is pleasant to note that the Lagos radar is now re-activated. The NAMA management has also made considerable effort towards achieving total radar cov­erage for the country, but this ef­fort is being marred by political intrigues. It is hoped that the pro­posed acquisition and installation of these surveillance systems will be allowed to see the light of day as it will not only be in the inter­est of flight safety, but most im­portantly in the interest of na­tional security as it will safeguard the territorial integrity of our air­space.

Due to the lack of a com­prehensive or automated air traffic management system, the pro­vision of Air Traffic control ser­vice in Nigeria is totally procedural with the attendant flight delays and the consequent high cost of op­erations for operators. The erratic nature of the available but obso­lete High Frequency (HF) commu­nication facilities is another com­pounding factor as it impedes on traffic coordination and conse­quently leading to poor traffic plan­ning and control. It is in this re­gard one will urgently call on the government to regard that one will urgently call on the government to properly assist NAMA in the phased implementation of the pro­posed communication, Navigation, Surveillance / air Traffic Manage­ment (CNS/ ATM) 1CAO Scheme which will avail us of the use of satellite based systems to enhance radio communication, navigation, surveillance as well as the provision of Air Traffic Ser­vices in Nigeria. This implies the separation of Air Traffic Services units to en­hance the provision of air traffic services.

To a large extent, the unnec­essary delays flights are subjected to at peak periods can be attrib­uted to undue congestion of ATCC frequencies due over concentra­tion of ATS responsibilities on a single or few ATS units. However, it is also very positive to note that vertical sectorisation is being ex­perimented in Lagos, while Abuja, Port Harcourt and Maiduguri air­ports are experimenting with the provision of Aerodrome and Ap­proach Services, Separately. It is also commendable to note that this effort is seriously easing traffic flow at these stations. We hope same strategy be extended to the provision of Area Control service at Lagos, Kano, Abuja, Port Harcourt and Maiduguri Airports.

Personnel Training:

Fre­quent retraining programmes should be planned for both ATC personnel and flight crew mem­bers to keep them abreast with current developments within the industry. Again, the NAMA man­agement is vigorously implementing this strategy. It has organised series of refresher courses for its ATC personnel in addition to other course like search and Rescue; computer appreciation, Exchange programmes, safety and security Awareness, as well as the on go­ing Area Airways course, amongst others. However, with the planned Total Radar coverage, it is impera­tive that NAMA embarks on mass of the systems. In addition, ATC personnel should be economically, socially and psychologically mo­tivated to enhance their perfor­mance.

In spite of our extensive air­space, experts have insisted that Nigeria has very little or no air routes at all. This claim is largely supported by the lack of essential Navaids on such routes. With the replacement of old VORS with DVORD, it is hoped that the re­placed ones will be refurbished and possibly used to replaced the in­adequate NDBs at major reporting points to further encourage flight operations or positions or position reporting on such routes. It is now very obvious that full Instrument Approach proce­dures are only been carried out by training flights as most aircraft sim­ply prefer a visual or straight-In-Approach or terminal aids should be strategically planned to minimise the execution of time washing procedures. And where necessary, the establishment of equipped new ATS routes should be encouraged.

Provision of accurate Flight Data by flight Crew

A major problem which ATC encounters daily is the frequent poor position reporting by pilots. With the lack of a surveillance sys­tem, this problem assumes a more serious dimension as it results daily in air misses and unneces­sary flight delays. Pilots should therefore be urged to be disciplined and proficient in the conduct of their professional duties as this does not only complicate the dis­charge of ATC duties but equally endangers safety of lives and prop­erty. Other areas include possible reduction of cost of aviation fuel; Reduction of separation minimise in conjunction with a Radar system or carriage of ACAS or TCAS. Also a review of parking, landing fees or Enroute navigation charges can go a long way in positively enhancing flight operations in Ni­geria.

CONCLUSION:

From the above analysis, we have been able to critically assess the safety financial, operation as well as strategic implications of the adequacies of inadequacies of the ATC system on flight operations in Nigeria. However, irrespective of the categorisation of these impacts, the bottom line is that they all trans­late into financial costs or benefits to the operators. The magnitude of the above impacts cannot be over­emphasized if stock in taken of the loss of lives and the economic losses attributable to flight delays, cancellations, diversions or aircraft accidents which instructions. Therefore, NAMA in conjunction with NCAT should urgently com­mence re-training of Air Traffic Controllers in this sensitive area to remedy this anomaly. Also, pilots and controllers' Association should consider ways by which a joint forum can be cre­ated to periodically exchange ideas on how best to address common problems and consequently, enhance air safety.

Above all, the on go­ing aviation policy re­view should objectively review the funding of NAMA as the responsibil­ity of air safety square lies on her.