Agenda Item 8: HF Planning issues in AFI Presented by Mary Obeng RO/CNS, ICAO Dakar

International Civil Aviation OrganisationMiddle East Office

Seminar on Aeronautical Spectrum ManagementCairo 4-6 June 2006

International Civil Aviation OrganisationMiddle East Office

Seminar on Aeronautical Spectrum ManagementCairo 4-6 June 2006

Agenda Item 8: HF Planning issues in AFI

Presented by Mary ObengRO/CNS, ICAO Dakar

INTRODUCTIONINTRODUCTION

• Due to increase in VHF coverage, there has been considerable decrease in the use of HF in AFI. However, IFALPA has been complaining of some HF congestion in AFI, notably AFI-3 (11300 KHz) and AFI-4 (8894 KHz).

• A COM survey was conducted by IFALPA and IATA

on VHF and HF coverage in the AFI Region to see how best the congestion could be eased.

Objectives of the SurveyObjectives of the Survey

• Establish status of implementation of mobile communications throughout the region

• Monitor progress in extension of VHF radio coverage

• Identify deficiencies in aeronautical mobile service coverage

• Assess problems of congestion on mobile frequencies and the extent to which they are used for ground/ground coordination

• Provide information to the COM/SG which will be useful in planning the improvement of air/ground communications

The Survey FormThe Survey Form

Call sign:   Origin:   Date:

Aircraft type:   Destination:   Signed:

Position:   Time: z Flight Level:  

Communications information

ATS Unit:   Strength Clarity Congestion

Fre-quency:

VHF (SEE NOTE 3) 1 – 2 – 3 – 4 - 5 1 – 2 – 3 – 4 - 5Low – Medium - High

HF 1 – 2 – 3 – 4 - 5 1 – 2 – 3 – 4 - 5Low – Medium -

High

Was the frequency apparently in use for ground/ground co-ordination? Yes No

Comments: 

IATA Mobile Communications Survey - 2000

Last Survey made in 1994

Responding to decision 4/16 of COM SG/4

Survey conducted in cooperation between IATA &

IFALPA

Dates – 20 April – 30 May 2000

More than 1140 pilot reports received

Analysis by IATA Regional Office using Access

database

Main ConclusionsMain Conclusions

• Higher proportion of calls are being made on VHFcompared to 1994

• HF still the only means available in significant portions of the AFI Region en route

• Noticeable improvement in average quality of communications, in line with increased availability of VHF

• Some reduction in congestion on AFI-4 family of frequencies but severe congestion persists on AFI-3 (11300Khz)

• Congestion directly associated to lack of VHF cover and non availability of ATS/DS

1994 2000

Use of VHF 1994 - 2000

HF HFVHF VHF

• 1994 - 37% of reports – VHF

• 2000 – 54% of reports - VHF

VHF EXTENTIONS IN SOUTHERNAND EASTERN AFI ALSO ACCRALUANDA,N’DJAMENA,KANO,NIAMEY,TUNIS FIRS

0%

20%

40%

60%

80%

100%

Percentage Use of VHF by FIR - 2000

0

5

10

15

20

25

30

35

40

Per

cen

tag

e

0 1 2 3 4 5

Strength

1994

2000

Strength 1994 vs 2000

Quality of Communications

0

5

10

15

20

25

30

35

Perc

en

tag

e

0 1 2 3 4 5

Clarity

1994

2000

Clarity 1994 vs 2000

Quality of Communications

1994 2000

3x3 or better 3x3 or better

Quality 1994 vs 2000

• 1994 - 63% of reports 3x3 or better

• 2000 – 79% or reports 3x3 or better

0%

20%

40%

60%

80%

100%

Quality by FIR

3x3 or better Worse than 3x3

Quality by FIR - 2000

Deficiencies in Mobile Coverage

The survey identifies those positions where mobile communications deficiencies occur

Following slides show positions where repetitive reports indicate difficulties in air/ground communication in both HF and VHF

All reports used in these slides indicate quality of communication less than 3x3

Deficiencies in Mobile coverage

Abidjan• MISLA

Luanda Alger

• ATAFA; Djanet; MOKAT; NSL; RAZEL; ROFER;

Khartoum• ALVOR; ME; Malakal;

Kinshasa• Buta Zega; KIBRO; MERON; SOBTO; TALAC;

USDUP

N’djamena• MERON

Tripoli• Kufra; NALUT; SEB;

Deficiencies in Mobile coverage

0

10

20

30

40

50

60

70

80

90

8894

8903

1130

0

1329

4

8861

6586

8879

6535

1129

1

8898

5517

HF Frequencies – by number of reports

ALG; KAN; NIM; AFI-2

ADD; CAI; KRT; MGQ; NBO; TIP

AFI-3

FIHAFI-4

DKR; ROBAFI-1

ACC; ABJAFI-4

DAR; MRU; SEZ; TNRINO-1

ACC; FIH; GBE; KAN; LAD; NDJ; NIM

AFI-4

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

KRT NBO TIP ADD KAN0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

KRT TIP NDJ LAD NBO

Congestion by FIR

•Percentage of Reports indicating HIGH congestion - Top Five

•Percentage of Reports indicating HIGH and/or MEDIUM congestion - Top Five

AFI-3

AFI-4

Frequency used for coordination

Use of Mobile Frequencies for Coordination

INADEQUATE ATS/DS IN AFI-3IMPLEMENTATION OF VSATCOM/SG/5 DECISION

Outcome of the surveyOutcome of the survey

• By improving aeronautical fixed services, implementation of the NAFISAT network will reduce the use of air-ground frequencies for ATS coordination (e.g. reduction of congestion on HF frequency 11300KHz.

• NAFISAT MOU has been signed by Djibouti, Egypt, Eritrea, Libya, Kenya (Somalia), Civil Aviation Caretaker Authority (CACAS) Seychelles, Sudan, Uganda, Tanzania, Yemen, ATNS and IATA hopefully Ethiopia and Saudi Arabia will join the network.

• NAFISAT contract already awarded. The network is expected to be operational by 2007.