Reporter's concern
The reporter expressed a safety concern regarding the confusion surrounding which frequency should be used at aerodromes which do not have a dedicated CTAF allocated.
The reporter has recently been advised by an Air Safety Advisor that the Area frequency should be used at non-towered aerodromes which do not have a CTAF allocated. This contradicts the information which was supplied by CASA in response to REPCON AR201400031.
If there is confusion by the CASA Air Safety Advisors then there will be confusion throughout the industry.
The reporter has suggested that CASA should release a NOTAM to pilots to clarify the issue.
A second report was received in relation to this and forwarded to CASA:
CASA's release of Civil Aviation Advisory Publication 166-1(2) has created a potential safety risk that undermines the concept of radio-alerted see and avoid at non-towered aerodromes that do not have a CTAF, which is likely the majority of aerodromes and airstrips in Australia.
To summarise the timeline whereby this situation has developed:
- More than a decade ago, CASA and Airservices Australia widely published a NAS concept which included a nationwide Multicom frequency of 126.7 MHz. The Multicom was the frequency to be used at every non-towered aerodrome and airstrip in Australia that does not have a CTAF.
- Airservices Australia continues to publish the Multicom concept in its AIP Book. Refer to current AIP GEN page 2.2-17 for the Multicom definition, and to ENR page 1.4-8 para 3.2.1 for an elaboration.
- CASA updated CAAP 166-1 to version 2 last December. At paragraph 6.6.2, this version specifically discounts the use of 126.7 MHz in favour of the Area Frequency. Previous versions of the CAAP did not have this statement.
- Therefore, since December last year, pilots flying in Australia have had conflicting information from the airspace regulator and the airspace service provider as to the appropriate frequency to use at non-towered aerodromes without a CTAF. This is a situation potentially worse than unalerted see and avoid because of the 'comfort' (expectation) that radio-alerted see and avoid procedures provide.
Regulator's response (Regulator 1)
I refer to your emails of 1 July 2014 and 23 July 2014 requesting comment by the Civil Aviation Safety Authority (CASA) on Australian Transport Safety Bureau REPCON AR201400052 about reported concerns regarding the confusion over which frequency to use at non-towered aerodromes which do not have a CTAF.
CASA has reviewed the REPCON. Civil Aviation Advisory Publication (CAAP) 166-1 provides advice on the correct frequency to use in the vicinity of a non-controlled aerodrome. The equivalent advice in the Aeronautical Information Publication (AIP) currently does not align with the CAAP. An AIP amendment rectifying this inconsistency comes into effect on 21 August 2014. In the interim, a Notice to Airmen has been issued to inform pilots about the correct frequencies to use at non-controlled aerodromes. CASA has also taken action to standardise the advice given by CASA's Aviation Safety Advisors.
It was identified in the second report related to this REPCON that paragraph 6.6.2 of CAAP 166-1 (2) appears to "discount" the use of 126.7 MHz (the Multicom frequency) in favour of the area frequency. There is a note following that paragraph, which if read in isolation could give that impression. To address this, CASA has undertaken to amend that section of CAAP 166-1 (2) to ensure it is consistent with the 21 August 2014 AIP amendment and the NOTAM. CASA would like to encourage the REPCON reporters to review the educational material on operations at non-controlled aerodromes which further explain frequency use at these aerodromes. The educational package can be accessed at:
www.casa.gov.au
HEAD OFFICE NOTAM C119/14
C119/14
OPERATIONAL FREQUENCY REQUIREMENTS
IN LIEU OF CURRENT AIP INFORMATION REGARDING OPERATIONS AT OR IN THE VICINITY OF NON-CONTROLLED AERODROMES, PILOTS MUST USE THE FOLLOWING FREQUENCIES FOR BROADCASTS:
A. IN THE VICINITY OF AN AERODROME DEPICTED ON AERONAUTICAL CHARTS, WITH A DISCRETE FREQUENCY, THE DISCRETE CTAF SHOWN (INCLUDING BROADCAST AREA CTAF), OR OTHERWISE;
B. IN THE VICINITY OF AN AERODROME DEPICTED ON AERONAUTICAL CHARTS, WITH NO DISCRETE FREQUENCY SHOWN, THE CTAF 126.7;
OR
C. IN ALL OTHER CASES, AREA VHF.
PROCEDURES INCORPORATED IN AIP EFFECTIVE 21 AUG 2014.
FROM 07 180435 TO 08 201559