{"id":"F2009L01504","name":"AD/RAD/87 Amdt 1 - Thales VHF Data Radios","slug":"ad-rad-87-amdt-1-thales-vhf-data-radios","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":78118,"registerId":"commonwealth-F2009L01504-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Radio Communication and Navigation Equip","sectionType":"division","heading":"Radio Communication and Navigation Equipment","content":"### Radio Communication and Navigation Equipment\n\n| AD/RAD/87 Amdt 1 | Thales VHF Data Radios | 5/2009 |\n| ---------------- | ---------------------- | ------ |\n\n```html\n

Applicability:

Thales Communications France VHF data radios, with the following part numbers (P/N) and serial number (S/N) range:

P/N

EVR716-01-0100A
EVR716-01-0200A
EVR716-11-0300A
EVR716-11-0350A
EVR750-03-0100A

All S/N up to but not including S/N

2546
2546
2594
2932
2546

Note 1: These radios are known to be installed on, but not limited to, the following aircraft:

Airbus A318, A319, A320, A321, A330, A340 (all series)

Boeing 717, 727, 737, 747, 757, 767, 777 (all series)

Bombardier (de Havilland) DHC-8-400 series

Requirement:

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):

Data Radio P/N

EVR716-11-0300A and
EVR716-11-0350A

EVR716-01-0200A


EVR716-01-0100A and
EVR750-03-0100A

Service Bulletin

EVR716-23-015


EVR716-23-012 Initial Issue or
EVR716-23-012 Rev 01

EVR7-23-05 Initial Issue or
EVR7-23-05 Rev 01

Note 2: EASA AD 2006-0334R1 refers.

\n```\n\n| Compliance: | No later than 42 months after 15 February 2007, the effective date of the original issue of this Directive. |\n| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| | This Amendment becomes effective on 7 May 2009. |\n| Background: | During the past few years, a phenomenon known as ‘PLOC’ (Prolonged Loss of Communications) has emerged. Over one thousand reports of this type of problem have been received from operators of various types of aircraft with different manufacturer’s equipment. It is suspected that the actual number of occurrences is higher, but due to some ‘PLOC’ occurrences having a short time interval they were either not noticed by the crew or not reported. Various studies were performed by Eurocontrol, CAA(UK) and operators to determine if there was a common reason for the occurrences. The results were not totally conclusive because other technical reasons, within the reported occurrences, may have caused the crew to experience a loss of communication. One type of ‘PLOC’ occurrence can be caused by equipment not receiving radio communication from an Air Traffic Controller or another aircraft. Typically, this type of failure is temporary and can be corrected by the crew of the aircraft transmitting a radio message. Following this transmission, the equipment correctly receives all incoming radio signals. This type of failure is referred to a ‘sleeping receiver’ problem.This type of problem causes workload issues for the Air Traffic Controller and can result in a reduction in safety levels. It is important, therefore, to do all that is possible to reduce or eliminate this type of occurrence.Thales, during exhaustive testing, managed to re-create the problem of the ‘sleeping receiver’ once. Further testing failed to induce the failure and the actual cause of the problem still remains unknown.Thales, however, instigated a design change to eliminate the possibility of this type of occurrence by checking every 20ms, when not transmitting, that the \"sleeping receiver\" conditions are not fulfilled and by forcing it into receive mode if it is not the case. The modified Thales VHF data radio is now installed on some aircraft. Since installing the modified radio, no reports of any ‘PLOC’ occurrences attributable to a ‘sleeping receiver’ have been received.For this reason, it is considered that the modification as per the Thales Service Bulletins should be mandatory for all aircraft with these models of radio installed. |\n| | This Amendment corrects some minor omissions from the original issue of the Directive and extends compliance by 12 months. |\n\n| | The original issue of this Directive became effective on 15 February 2007. |\n| --- | -------------------------------------------------------------------------- |\n\n![](image.001.png) \nJames Coyne \nDelegate of the Civil Aviation Safety Authority\n\n26 March 2009","sortOrder":0},{"sectionNumber":"AD/RAD/87 Amdt 1","sectionType":"part","heading":"AD/RAD/87 Amdt 1","content":"## AD/RAD/87 Amdt 1","sortOrder":1},{"sectionNumber":"Thales VHF Data Radios","sectionType":"part","heading":"Thales VHF Data Radios","content":"## Thales VHF Data Radios","sortOrder":2},{"sectionNumber":"5/2009","sectionType":"part","heading":"5/2009","content":"## 5/2009","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment does not broaden which radios or aircraft are subject to the modification but corrects minor omissions from the original Directive and extends the compliance deadline by 12 months; the required corrective action (apply specified Thales service bulletins or later EASA‑approved revisions) and overall applicability remain materially the same."},"complexity_factors":["Technical specificity: exact Thales part numbers and serial number cut‑offs determine applicability (source lists multiple P/N and S/N ranges).","Multiple approved corrective documents: different service bulletin numbers and allowed later EASA‑approved revisions must be applied.","Cross‑reference to external regulator material: refers to and relies on EASA AD 2006-0334R1 and EASA approval for later revisions.","Compliance timing: original 42‑month deadline from 15 Feb 2007, then amended effective date and a 12‑month extension affect scheduling and recordkeeping.","Fleet breadth: radios are installed across multiple airliner types, so coordination across operators and maintenance organisations is required.","Uncertain root cause: remedy is a preventive design change addressing an intermittently reproducible fault, raising verification and testing burdens."],"plain_english_summary":"Requires operators to modify specified Thales VHF data radios by installing the Thales service‑bulletin upgrades (or later revisions approved by EASA) to eliminate a ‘sleeping receiver’ fault that can cause prolonged loss of communications. It affects aircraft fitted with those radios (examples include various Airbus, Boeing and Bombardier types); this amendment corrects minor omissions from the original directive and extends the compliance deadline by 12 months."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment remains tightly scoped to its original purpose. It corrects minor omissions from the original 2007 directive and extends the compliance deadline by 12 months, but does not expand the applicability to new aircraft types, radio models, or introduce new requirements beyond the original safety modification."},"complexity_factors":["Highly technical subject matter (avionics, radio protocols, serial number tracking)","Multiple part numbers with different serial number cut-offs requiring cross-referencing","Three different Service Bulletins required depending on specific part number","Nested effective dates (original directive date, amendment effective date, compliance deadline calculated from original date)","Reference to external European Aviation Safety Agency (EASA) approval and foreign airworthiness directive (EASA AD 2006-0334R1)"],"plain_english_summary":"This CASA Airworthiness Directive mandates a modification to certain Thales VHF radios (specified part numbers/serials) fitted to many Airbus, Boeing and Q400 types to fix a “sleeping receiver” fault that can cause prolonged loss of communications. The Thales fix adds a 20 ms check to force the receiver back into receive mode. The amendment extends the original compliance deadline by 12 months and is effective 7 May 2009."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rad-87-amdt-1-thales-vhf-data-radios","history":"/api/acts/ad-rad-87-amdt-1-thales-vhf-data-radios/history","analysis":"/api/acts/ad-rad-87-amdt-1-thales-vhf-data-radios/analysis","conflicts":"/api/acts/ad-rad-87-amdt-1-thales-vhf-data-radios/conflicts","importantCases":"/api/acts/ad-rad-87-amdt-1-thales-vhf-data-radios/important-cases","documents":"/api/acts/ad-rad-87-amdt-1-thales-vhf-data-radios/documents"}}