AD/RAD/87 Amdt 1 - Thales VHF Data Radios

The central concept is the Prolonged Loss of Communications (PLOC) failure mode. According to the background section of the source, PLOC is a temporary inability of a VHF data radio to receive incoming signals from air traffic control or other aircraft. The pilot typically becomes aware of the problem only when they notice they are not receiving expected calls, or when ATC queries them. The failure is intermittent and can be corrected by the crew transmitting a message; the act of transmitting resets the radio's receive function. This specific subtype is referred to as a "sleeping receiver". The cause of the sleeping receiver is not fully understood. Thales recreated it only once during testing. Despite that, Thales implemented a design change that monitors the radio's state every 20 milliseconds. If the radio is in a state where it cannot receive incoming signals, the software forces it back into receive mode. The modified radio has since operated without any reported PLOC incidents attributable to this failure. The AD makes that modification mandatory for all affected radios. Applicability is defined by part number and serial number ranges. The table lists five part numbers and the serial number ceiling for each. For example, EVR716-11-0300A and EVR716-11-0350A are captured up to serial number 2594; EVR716-01-0200A up to 2546. Radios with serial numbers equal to or higher than the listed numbers are presumably already modified or from a later production run. The note confirms the radios are known to be installed on Airbus A318, A319, A320, A321, A330, A340 (all series), Boeing 717, 727, 737, 747, 757, 767, 777 (all series), and Bombardier DHC-8-400 series. This list is not exhaustive; the AD applies to any aircraft with those radios. Compliance must be completed no later than 42 months after the original effective date of the original directive (15 February 2007). That deadline is extended by 12 months compared with the original compliance period, so the original must have required compliance within 30 months. Service bulletins are the approved means of modification: EVR716-23-015 for P/N EVR716-11-0300A and EVR716-11-0350A; EVR716-23-012 (initial issue or Rev 01) for EVR716-01-0200A; and EVR7-23-05 (initial issue or Rev 01) for EVR716-01-0100A and EVR750-03-0100A. Later revisions of these bulletins approved by EASA are also acceptable. The AD refers to EASA AD 2006-0334R1, indicating that this Australian directive aligns with a European directive on the same topic. Amendment details: the original AD/RAD/87 became effective 15 February 2007; this Amendment 1 corrects minor omissions and adds 12 months to the compliance window, effective 7 May 2009. The delegate of CASA signs the directive, confirming its legal force under Australian aviation regulations.

The primary group affected comprises operators of aircraft that have the five affected Thales VHF data radio part numbers installed. The source specifically names Airbus A318, A319, A320, A321, A330, A340 (all series), Boeing 717, 727, 737, 747, 757, 767, 777 (all series), and Bombardier DHC-8-400 series as examples. However, the AD applies to any aircraft type on which those radios are fitted, not just those listed. That means operators of large commercial jet aircraft, regional turboprops, and potentially any other type that uses Thales VHF data radios with those part numbers must check their fleets. The serial number cutoff means only radios manufactured before a certain batch are caught. Operators who have already installed modified radios (e.g., from later production or after previous retrofits) may be unaffected if the serial number is above the threshold. Maintenance organisations that perform airframe and radio work must have access to the Thales service bulletins and must perform the modification correctly. They must also update aircraft maintenance records to show compliance. The modification is a one-time task, not recurrent. Air traffic controllers are indirectly affected because the AD aims to reduce PLOC events that create workload for them. The background states that PLOC causes "workload issues" for controllers and can reduce safety levels, so controllers have an interest in the AD's effectiveness. Thales Communications France is the manufacturer; its service bulletins define the modification. Thales designed the software change and presumably provides the modification kits or services. Regulators including CASA and EASA are involved: CASA issues the Australian AD; EASA issues the corresponding AD 2006-0334R1. The Australian AD recognises EASA-approved revisions, creating cross-regulatory alignment. Private pilots or small operators who operate any aircraft with these radios (e.g., corporate jets, smaller airliners) are also captured. The compliance burden will fall on them to identify radios, acquire bulletins, schedule downtime, and pay for modification labour and any parts. The extended compliance period reduces the urgency but does not eliminate the cost. Because the AD applies to radios already in service, operators must track serial numbers, which might not be immediately obvious. Aircraft lessors and financiers may also have an interest, as unmodified radios could affect resale value or lease terms. In short, the affected parties are any entity or person who owns, operates, maintains, or finances aircraft equipped with the listed radios, plus the manufacturers and regulators involved in the design and oversight of the fix.

The central duty imposed by this AD is that operators must modify the affected VHF data radios if the modification has not already been performed. The modification must follow the specified Thales service bulletins or later EASA-approved revisions. The compliance deadline is "no later than 42 months after 15 February 2007, the effective date of the original issue of this Directive." Because the amendment extends compliance by 12 months, the original compliance period was 30 months; the new allowed period is 42 months. Operators must calculate the precise calendar date and ensure the modification is completed before that date. The duty applies to each affected radio individually; if an aircraft has more than one such radio, all must be modified. The duty is mandatory: the directive uses the word "must". There is no provision for opting out, requesting an alternative means of compliance, or extending the deadline further. Operators do have a right to use later revisions of the service bulletins that have been approved by EASA. This allows them to use the most up-to-date modification instructions if Thales issues subsequent revisions. The source does not specify whether CASA itself must approve those revisions; it states only that amendments from EASA are acceptable. Operators also have a right to rely on Note 1, which confirms that the listed aircraft types are examples but not exhaustive. That means if a radio is installed on an aircraft type not listed, the duty still applies. Operators can also verify whether a particular radio serial number is affected: the AD gives a specific cutoff (e.g., all S/N up to but not including 2546 for some part numbers). Radios with serial numbers equal to or greater than the listed numbers are not affected by this AD. Operators have the right to check their records and conclude if no action is required. The source does not explicitly state a right to appeal or seek an exemption, but such rights may exist under the general CASR framework outside this AD. The background provides information but does not impose any separate duty. The compliance entry in the table indicates that the amendment itself becomes effective on 7 May 2009. Operators cannot delay beyond that date for the extended compliance period; the extension was already incorporated into the amendment. The duty to modify by the deadline is fixed. There is no duty to perform periodic checks after modification; it is a one-time corrective action. However, the duty to maintain the radio in an airworthy condition continues under other regulations. The duty to keep records of compliance may exist under Part 42 of CASR, though not stated here.

The source text does not prescribe any specific penalties for non-compliance with this Airworthiness Directive. However, under the Australian regulatory framework for aviation, failure to comply with a mandatory airworthiness directive is a serious matter. Enforcement would occur under the provisions of the Civil Aviation Safety Regulations 1998 (CASR), which CASA administers. The AD itself is issued under the authority of the Civil Aviation Safety Act 1988 and CASR Part 39. Non-compliance can result in civil penalties, suspension or revocation of an aircraft's airworthiness certificate, or even criminal prosecution depending on the circumstances. CASA has the power to ground an aircraft if it finds it is not airworthy due to non-compliance with an AD. The source notes that the background references "reduction in safety levels" - enforcement actions would be linked to that safety risk. While the AD does not list fines or imprisonment terms, typical enforcement under CASR for AD compliance includes penalties of up to 500 penalty units for an individual (currently about AUD 156,000) or more for corporate entities. Additionally, pilots and operators may face direct liability. The AD's mandatory modification is a condition of continuing airworthiness; operating an aircraft after the compliance deadline without having done the modification would likely be a breach of the aircraft's airworthiness certificate. The Australian Transport Safety Bureau could also investigate incidents related to PLOC, and if an unmodified radio is found to have contributed, that would be an aggravating factor. Enforcement could be triggered by a routine inspection, a report from a maintenance organisation, an occurrence report, or a CASA audit. The AD does not create any special enforcement regime; it relies on the existing CASR enforcement machinery. The original issue had a shorter compliance period; the amendment extending it by 12 months might have been a response to industry feedback about feasibility, but that does not weaken enforcement for those who then fail to meet the extended deadline. Operators should treat the directive as having the full force of law. The delegate of CASA who signed the directive, James Coyne, has the authority to issue such directives, and the amendment is effective from 7 May 2009. Any failure to comply after the applicable deadline would be a regulatory breach. The source does not mention any litigation or specific enforcement action related to this AD, so the penalties are a matter of general law. Operators should consult CASR Part 39 and relevant CASA enforcement policies for precise consequences.

This Airworthiness Directive operates as a specific mandatory airworthiness requirement under the Australian regulatory system. It is issued by CASA under the Civil Aviation Safety Regulations 1998 (CASR), particularly Part 39 which deals with airworthiness directives. The AD is subordinate to the Civil Aviation Safety Act 1988 and must be read together with other CASR parts. For example, CASR Part 42 (Continuing Airworthiness) requires an operator to maintain an aircraft in an airworthy condition and to comply with all applicable ADs. Part 145 (Maintenance Organisations) requires approved maintenance organisations to perform work in accordance with approved data, which includes service bulletins mandated by ADs. The AD also interacts with Parts 21 and 25 covering type certification and design changes. The source specifically references EASA AD 2006-0334R1, the European equivalent. This means that for aircraft on the Australian register, the CASA AD is the applicable directive, but EASA's AD may apply to European-registered aircraft. For operators with aircraft operating internationally, compliance with EASA's AD may also be necessary depending on the registry. The AD states that the modification can be performed as per Thales service bulletins or "later revisions approved by the European Aviation Safety Agency". This cross-references EASA's approval process. It also implies that the modification is considered an equivalent level of safety for Australian purposes. The AD may interact with bilateral agreements between Australia and Europe regarding maintenance approvals. If an operator has already complied with the EASA AD using an approved alternative method, that may also satisfy the Australian AD, but the source does not explicitly say so; it only mentions the service bulletins. The amendment corrects "minor omissions" from the original AD/RAD/87. This means the original AD contained errors or missing details that could have caused confusion or incorrect compliance. The amendment clarifies those points. The 12-month extension may interact with maintenance schedules originally set under the shorter compliance period; maintenance plans would need to be revised. The AD does not replace or override any other laws; it adds a specific requirement. It should be read alongside the aircraft's maintenance program, the flight manual, and any other ADs applicable to the aircraft. The background mentions studies by Eurocontrol and the UK CAA, but those are not Australian law - they informed the decision to issue the AD. The AD itself is self-contained and does not incorporate those studies by reference. It also references Thales service bulletins by number and revision, which are proprietary documents. Operators must obtain those bulletins. The AD does not address data protection, competition law, or employment law. Its interaction is solely within aviation safety regulation.

The source document is Amendment 1 to AD/RAD/87. The original issue of AD/RAD/87 became effective on 15 February 2007. The amendment is dated 26 March 2009 and becomes effective on 7 May 2009. The amendment was signed by James Coyne as delegate of the Civil Aviation Safety Authority. The background section states that this Amendment 1 "corrects some minor omissions from the original issue of the Directive and extends compliance by 12 months." The original compliance period was presumably 30 months from 15 February 2007, or some other period that made the original compliance date fall before the amendment. The amendment revises the requirement to say "no later than 42 months after 15 February 2007". That is an extension of 12 months (from 30 months to 42 months). The amendment also corrects "minor omissions" - possibly the original AD may have omitted some part numbers, serial number ranges, or service bulletin references. The amendment includes the full current table of part numbers, serial numbers, and bulletins. It also adds the EASA AD reference (Note 2). The original might have lacked that reference. The note about "known to be installed on" aircraft types is also part of the amendment; we cannot be sure it was in the original. The amendment also clarifies the compliance language: "If not previously accomplished, modify the VHF data radios by incorporating the following Thales Communications Service Bulletins or later revisions approved by the European Aviation Safety Agency (EASA)." The original might have had different wording. The inclusion of "later revisions approved by EASA" may be a new addition. The note about EASA AD 2006-0334R1 is also likely new, given it appears in the background but as Note 2 in the table. The amendment increases the compliance time by 12 months, presumably to give operators more time to acquire service bulletins, schedule modifications, and incorporate the change during regular maintenance. The amendment does not change the nature of the modification, only the timeframe and corrections. The original AD would have applied to the same part numbers and serial numbers, but perhaps the serial number cutoffs might have been slightly different - the source does not say. The term "Amdt 1" on the document indicates it is the first revision. There might be later amendments that the source does not include, but we cannot discuss those. The document is identified as AD/RAD/87 Amdt 1 and also labelled as 5/2009, probably a CASA AD number. The effective date of the amendment is 7 May 2009, so from that date forward the new compliance deadline applies. Operators who had already scheduled compliance under the original deadline would have to adjust if they had not yet completed it. There is no mention of any prior amendments to the original, so this is the first and only amendment as of the source date.

The source text does not mention any litigation, court cases, or legal challenges related to AD/RAD/87 or its amendment. Given that this is a technical airworthiness directive addressing a specific equipment design issue, it is unlikely to have been litigated. Airworthiness directives are usually compliance instruments that operators follow without court proceedings. They are based on safety findings and manufacturers' recommendations. The background indicates that the PLOC problem was studied by Eurocontrol and the UK CAA, but no litigation arose from those studies. Thales' design change was implemented voluntarily and then mandated. There is no suggestion that any party disputed the AD's validity or sought judicial review. The AD was issued by CASA under its statutory powers, and such directives are generally not subject to challenge unless they exceed statutory authority or are procedurally flawed. The delegate signed on 26 March 2009, and the amendment became effective 7 May 2009. No evidence of any operator challenging the AD exists in the source. It is possible that some operators provided feedback that led to the 12-month extension, but that is not litigation. The source also does not reference any accident investigation reports or court findings related to PLOC. The absence of litigation history is itself notable: it suggests that the AD was relatively uncontroversial and the industry accepted the necessity of the modification. Operators might have preferred the longer compliance period, which the amendment granted. The only potential legal interaction is with EASA AD 2006-0334R1, which is referenced; if there were any challenge to the EASA AD, it would be in European courts, not Australian. Since the source does not provide any details, any discussion of litigation history would be speculation. Therefore, the accurate statement is: the source contains no reference to any litigation, and there is no publicly known legal action associated with this directive as of the document date. The directive appears to have been implemented without dispute. This is typical for safety-critical ADs that address identified failure modes. However, the lack of litigation does not mean the AD was cost-free; operators might have opposed the compliance timeline informally. But that opposition did not reach the courts. In summary, the litigation history for AD/RAD/87 Amdt 1 appears to be nil based on the source material.

Several aspects of this AD might catch operators off guard. First, the compliance deadline is not simply "42 months from 7 May 2009". The source states: "Compliance: No later than 42 months after 15 February 2007, the effective date of the original issue of this Directive." That means the deadline is 15 August 2010 (42 months after 15 February 2007), regardless of when the amendment was published. An operator who only reads the amendment date might mistakenly calculate 42 months from May 2009, resulting in a later deadline of November 2012. That would be wrong and would cause non-compliance. Second, the serial number cutoffs are ambiguous. The table says "All S/N up to but not including S/N" and then lists numbers. For example, EVR716-01-0100A and EVR750-03-0100A list "2546". That means radios with serial numbers less than 2546 are affected; those with S/N 2546 or greater are not. But the table lists multiple part numbers with the same cutoff. Operators must check each radio individually. The note says the radios are known to be installed on certain aircraft types, but the list is not exhaustive. An aircraft type not listed may still have the affected radio. Third, the service bulletins must be obtained and followed precisely. The source says "later revisions approved by the European Aviation Safety Agency (EASA)". It does not say "approved by CASA". That means if Thales issues a Rev 02 that EASA approves, it is acceptable without CASA separately approving it. Operators relying on Australian approval only might miss that. Fourth, the modification is required only "if not previously accomplished." Some aircraft may have had the radios replaced with newer ones that already incorporate the design change. However, "previously accomplished" might refer to a previous modification, not a factory-installed radio. The serial number cutoff already excludes later-production radios, but a radio with a serial number below the cutoff might have been modified under a prior service bulletin. Operators need records to prove that. Fifth, the AD does not specify who must accomplish the modification. It simply says "modify the VHF data radios". The duty falls on the operator, but the work can be done by an appropriately rated maintenance organisation. However, the operator remains responsible for compliance. Sixth, the AD references EASA AD 2006-0334R1 as a note. That European directive may have different compliance requirements for European operators. Australian operators cannot rely on that EASA AD to satisfy the Australian AD unless they also comply with the letter of the CASA AD. The note is for cross-reference, not substitution. Seventh, the amendment corrects "minor omissions". The nature of those omissions is not described. An operator who relied on the original AD and missed those omissions may have been operating for some time without realising the AD applied. The amendment clarifies, but the original AD still applied. Operators should review their records to ensure they were not already obligated under the original. Eighth, the compliance period of 42 months includes 12 months of extension. The original period was 30 months. Operators who did not start planning for the original deadline now have an extra year. But they should not delay until the last minute, as obtaining service bulletins and scheduling maintenance may take time. Ninth, the AD applies to radios that are "known to be installed on" the listed aircraft, but the radios could also be installed on other aircraft not listed. The onus is on the operator to check the actual part and serial numbers on their aircraft, not just the type certificate. Tenth, there is no exception for radios that are not used for VHF data communication but only for voice. The AD covers these radios regardless of how they are used.

Compliance with AD/RAD/87 Amdt 1 involves several concrete steps. Step 1: Identify whether the aircraft has any of the five listed Thales VHF data radio part numbers: EVR716-01-0100A, EVR716-01-0200A, EVR716-11-0300A, EVR716-11-0350A, and EVR750-03-0100A. This requires consulting the aircraft's equipment list, maintenance records, or physically inspecting the radios. Step 2: For each radio found, check the serial number against the cutoff numbers provided in the AD. For example, for EVR716-01-0100A and EVR750-03-0100A, all serial numbers less than 2546 are affected. For EVR716-11-0300A and EVR716-11-0350A, all serial numbers less than 2594 are affected. For EVR716-01-0200A, all serial numbers less than 2546 are affected. If the serial number is equal to or higher than the listed number, the radio is not affected by this AD. Step 3: If a radio is affected, determine whether it has already been modified. The AD says "if not previously accomplished". Look for maintenance entries indicating compliance with Thales service bulletins EVR716-23-015, EVR716-23-012, or EVR7-23-05 (or later EASA-approved revisions). If there is no such record, the modification is required. Step 4: Obtain the appropriate service bulletin from Thales Communications France. The AD specifies which bulletin applies per part number. For EVR716-11-0300A and EVR716-11-0350A, use EVR716-23-015. For EVR716-01-0200A, use EVR716-23-012 (initial issue or Rev 01). For EVR716-01-0100A and EVR750-03-0100A, use EVR7-23-05 (initial issue or Rev 01). Later revisions approved by EASA are also acceptable. Step 5: Perform the modification in accordance with the service bulletin. This likely involves updating software or firmware and potentially testing. The work should be carried out by an appropriately approved maintenance organisation (e.g., CASR Part 145 rated for avionics). Step 6: After completion, update the aircraft's maintenance records and logbook to document compliance with the AD. Note the service bulletin revision used, the date, and the person or organisation who performed the work. Step 7: Ensure compliance is achieved before the deadline: no later than 42 months after 15 February 2007, i.e., 15 August 2010. Even if the radio is installed on an aircraft that is not one of the listed Boeing or Airbus types, the same deadline applies. Step 8: If the aircraft has multiple affected radios (e.g., two VHF data radios), each must be modified. Step 9: Keep a copy of the AD and the service bulletin with the aircraft records for future reference. Step 10: Review the AD for any further amendments that may be published after 7 May 2009. This particular amendment is the only one in the source, but CASA could issue further amendments. Compliance should be monitored through CASA's AD listing. Operators should also note that if they have already complied with the original AD/RAD/87 using a different method, they should verify that the amendment does not require additional action (the amendment only corrects omissions and extends time, so prior compliance should still be valid). Step 11: If there is any doubt about the applicability or the modification, contact Thales technical support or CASA's airworthiness division for clarification. Options for alternative means of compliance (AMOC) may exist under CASR Part 39, but the AD does not mention AMOCs; operators would need to apply separately. Step 12: Ensure all affected aircraft in the fleet are accounted for, including those leased, borrowed, or out-of-service temporarily. The duty attaches to the aircraft, not just the operator. If an aircraft is sold before the deadline, the seller should ensure compliance or disclose the outstanding AD to the buyer. This is a one-time compliance task; no recurring inspections are required. Once the radio is modified, it is compliant for the life of that radio unless a new AD supersedes this one.