Accident - G-BXBU
G-BXBU.
AAIB investigation to Mudry Cap 10B, G-BXBU
Safety Recommendation: 2023-011
2023-011: It is recommended that the Civil Aviation Authority publish guidance for general aviation pilots on responding to unexpected weather deterioration, highlighting the factors affecting their performance and the benefits of planning before the flight how they will respond.
In addition to the guidance highlighted in the CAA’s initial response to this safety recommendation, the CAA is also developing a new Safety Sense Leaflet (SSL) dedicated to inadvertent entry into Instrument Meteorological Conditions (IMC) when operating under Visual Flight Rules (VFR). The SSL will include guidance on planning to avoid a ‘VFR into IMC’ scenario and what actions to take if a pilot is confronted with deteriorating weather conditions and ends up in IMC when not appropriately qualified.
The SSL has been developed with input from internal and external subject matter experts and is scheduled to be published by March 31st 2024.
The CAA considers the above actions satisfy the intent of the safety recommendation.
Adequate - Closed
Closed
AAIB Recommendation transmittal
Date
24/04/2023
Status
Open
CAA Initial Update
Date
20/07/2023
The CAA accepts this safety recommendation and has identified several publications, listed below, that cover handling unexpected weather deterioration including the factors affecting pilot performance, and the benefits of pre-flight planning. The General Aviation Unit (GAU) team has created a webpage dedicated to weather in GA operations, which will be populated with useful guidance for pilots, including flying in cloud.
The following publications provide useful guidance for pilots with regards to the topics highlighted in the safety recommendation.
- Inadvertent IMC Workshop replay — Astral Aviation Consulting
- Inadvertent IMC Workshop replay — Astral Aviation Consulting
- CAA8230_SafetySense_05-VFR_V5.pdf
- Weather guide to day trip planning — Astral Aviation Consulting
- Weather Forecast Decision Making — Astral Aviation Consulting
- Pre-flight planning - Airspace Safety
The GAU will continue to identify the best ways to draw pilot’s attention to this guidance and will also assess the need for additional material.
Status
Open
AAIB Classification
Date
16/08/2023
Status
Partially Adequate - Open
CAA Update
Date
29/02/2024
In addition to the guidance highlighted in the CAA’s initial response to this safety recommendation, the CAA is also developing a new Safety Sense Leaflet (SSL) dedicated to inadvertent entry into Instrument Meteorological Conditions (IMC) when operating under Visual Flight Rules (VFR). The SSL will include guidance on planning to avoid a ‘VFR into IMC’ scenario and what actions to take if a pilot is confronted with deteriorating weather conditions and ends up in IMC when not appropriately qualified.
The SSL has been developed with input from internal and external subject matter experts and is scheduled to be published by March 31st 2024.
The CAA considers the above actions satisfy the intent of the safety recommendation.
CAA Update
Date
31/05/2024
The previous CAA update for this safety recommendation indicated that a new Safety Sense Leaflet (SSL) was being developed to provide GA pilots with guidance on inadvertent entry into Instrument Meteorological Conditions (IMC) to mitigate the risk of loss of control or flight into terrain occurrences.
The CAA published the ‘VFR Flight into IMC’ SSL on May 7th 2024. The SSL offers guidance on how to avoid a ‘VFR into IMC’ scenario via effective pre-flight planning and what actions to take if confronted with deteriorating weather conditions when not qualified to fly in IMC.
AAIB Classification
Date
28/06/2024
Status
Adequate - Closed
Safety Recommendation: 2023-012
2023-012: It is recommended that the Civil Aviation Authority require air traffic controllers to receive training regarding the human performance characteristics and limitations associated with stress. This should include the verbal cues that may indicate that a pilot is operating under high stress, and mitigation strategies to help controllers deal with such event.
The CAA ATM Principal Inspectors have been monitoring units’ inclusion of safety incidents and accidents in refresher training as part of the ongoing oversight programme. They have been assured that this accident and learnings from it have been widely incorporated into refresher training. As such we do not believe that there would be benefit gained from issuing a Safety Notice to ANSPs at this point.
We previously advised that the syllabus, which forms the Acceptable Means of Compliance (AMC) for Assimilated Regulation (EU) 2015/340 (the ATCO licensing regulation will be reviewed in conjunction with the legislation changes proposed for UK Reg (EU) 2015/340.
Adequate - Open
November 2026
AAIB Recommendation transmittal
Date
24/04/2023
Status
Open
CAA Initial Update
Date
20/07/2023
The power to amend the legal requirements for the training of air traffic controllers rests with the Department for Transport (DfT).
The current, initial training syllabus for civilian air traffic controllers already includes recognition of stress and its symptoms, in self and in others (UK Regulation (EU) 2015/340). Equivalent training for military air traffic controllers, which would apply to any Distress and Diversion (“D&D”) cell controller, is outside the scope of the CAA’s oversight.
In addition to the existing material for civil air traffic controllers, the CAA recognises that additional educational material to highlight the verbal cues that might indicate stress could be beneficial, and will consider such material in the context of acceptable means of compliance to UK Regulation (EU) 2015/340 and our nascent work with the UK Flight Safety Committee to update CAP 745 - Aircraft Emergencies: Considerations for air traffic controllers.
Status
Open
AAIB Classification
Date
16/08/2023
Status
Partially Adequate - Open
CAA Update
Date
29/02/2024
The CAA is working in collaboration with the UK Flight Safety Committee (FSC) to develop a significant update to ‘Aircraft Emergencies: Considerations for air traffic controllers’ (CAP 745). This work includes broadening the scope of the document to include scenarios affecting general aviation activities and flight information service officers alongside air traffic controllers. Our aspiration is for the revised document to be published in Q4 2024, though we are reliant upon the expertise being volunteered by the members of the UK FSC.
The syllabus, which forms Acceptable Means of Compliance (AMC) for Assimilated Regulation (EU) 2015/340 (the ATCO licensing regulation) which provides the learning objectives for trainee ATCOs for the issue and revalidation of unit endorsements, is being reviewed and will include consideration of the intent of this Safety Recommendation. Amendment of AMC will be made in conjunction with the legislation changes being worked on for UK Reg (EU) 2015/340 and in accordance with the CAA Rulemaking Programme/Schedule.
CAA Update
Date
24/12/2024
The CAA continues to work with the UK Flight Safety Committee (FSC) to develop a significant update to ‘Aircraft Emergencies: Considerations for air traffic controllers’ (CAP 745). The intent is to broaden the scope of the document to include scenarios affecting general aviation activities and flight information service officers alongside air traffic controllers.
The CAA is reliant upon the expertise being volunteered by the members of the UK FSC and regretfully, the document has not yet been published but we are expecting to receive a mature draft from the drafting group in March 2025. It will then be reviewed by the CAA prior to publication.
The text of Assimilated regulation 2015/340 (Air Traffic Controllers Certificates and Licences) describing the function of the Distress & Diversion Cell is currently being amended to align with CAP 493 (MATS Pt 1) with a view to publishing in 2025 or early 2026, being subject to the rulemaking process and parliamentary time.
The ATM Inspectorate has seen evidence that this incident has been used by a number of ANSPs as material for ATCO refresher training for revalidation (e.g. NERL and NSL). The CAA will issue a Safety notice in the new year asking ANSPs to include this incident in refresher training if they have not already done so.
AAIB Classification
Date
24/01/2025
Status
Adequate - Open
CAA Update
Date
28/08/2025
The UK Flight Safety Committee Working Group has submitted a revised draft of CAP 745, Aircraft Emergencies, to the CAA for consideration. The CAA is sincerely grateful for the time and expertise that volunteers from both GATCO and BALPA have contributed to this effort.
The Airspace/ATM Policy team at the CAA will now review the draft and work closely with the UK Flight Safety Committee Working Group to provide CAA comment and input.
The CAA acknowledge the comment made by the AAIB regarding the focus of earlier iterations of the document being on multi-crew operations and will also seek to address the single pilot environment.
The CAA intends to issue a Safety notice asking ANSPs to include this incident in refresher training if they have not already done so. It will also reference the relevant content of CAP 745. However, it is worth noting that our oversight teams report that they have already seen evidence of this report being used in refresher training.
The CAA previously advised that the syllabus, which forms the Acceptable Means of Compliance (AMC) for Assimilated Regulation (EU) 2015/340 (the ATCO licensing regulation will be reviewed in conjunction with the legislation changes proposed for UK Reg (EU) 2015/340. Regrettably, this rulemaking activity has been delayed due to CAA resource availability and is unlikely to be published until 2027/8. The CAA acknowledge the AAIB’s suggestion that another CAA publication might be used to achieve the same outcome and will consider the feasibility of doing so.
The CAA expect to be able to provide the next update to this Safety Recommendation by February 2026.
AAIB Classification
Date
25/09/2025
Status
Adequate - Open
CAA Update
Date
26/02/2026
In previous updates, we indicated our intention to publish a Safety Notice to highlight the accident report to ANSPs requesting that it was included in refresher training. We felt it would be beneficial to align this with the publication of a revised CAP 745 ‘Aircraft Emergencies’. Unfortunately, publication of that document has been delayed due to resource/prioritisation.
However, the CAA ATM Principal Inspectors have been monitoring units’ inclusion of safety incidents and accidents in refresher training as part of the ongoing oversight programme. They have been assured that this accident and learnings from it have been widely incorporated into refresher training. As such we do not believe that there would be benefit gained from issuing a Safety Notice to ANSPs at this point.
We previously advised that the syllabus, which forms the Acceptable Means of Compliance (AMC) for Assimilated Regulation (EU) 2015/340 (the ATCO licensing regulation will be reviewed in conjunction with the legislation changes proposed for UK Reg (EU) 2015/340. Regrettably, this rulemaking activity has been delayed due to CAA resource availability and is unlikely to be published until 2027/8. This remains the case and I will continue to provide you with updates.
AAIB Classification
Date
26/03/2026
Status
Adequate - Open
Safety Recommendation: 2023-013
2023-013: It is recommended that the Civil Aviation Authority specify the types of information that air traffic controllers will obtain and record when responding to aircraft in an emergency to ensure that pilots’ needs are met and reported correctly if communicated to other air traffic control units.
In addition to existing text in CAP413 ‘Radiotelephony Manual’ we have identified CAP745 as the appropriate publication in which to promote the types of information that should be obtained and recorded by means of a checklist template. The draft CAP745 as developed by the Flight Safety Committee Working Group has been subject to an initial review by the Airspace/ATM Policy and Oversight teams. The review has concluded that a considerable amount of work will be required before the document could be published as a Civil Aviation Authority publication (CAP).
Partially Adequate - Open
November 2026
AAIB Recommendation transmittal
Date
24/04/2023
Status
20/07/2023
CAA Initial Update
The types of information that shall be contained in the emergency message passed by pilots are described in the Radiotelephony Manual (CAP 413) (Chapter 8 Paragraph 8.13). This information is reiterated in the Manual of Air Traffic Services (MATS) Part 1 (CAP 493), which is the manual used by civil air traffic controllers. Civil air traffic controllers (being those over which the CAA has oversight) are therefore advised through MATS of the pertinent information and are instructed through courses of basic and initial training to recognise pertinent data and to record it appropriately; this is a basic competency for air traffic controllers. This provides sufficient flexibility for an air traffic controller to consider what information they require from the pilot in an emergency and, importantly, when it is appropriate to obtain that information taking into account the human factors involved in such a situation.
However, a D&D cell will often, as in this case, be the first point of contact in an emergency and the military aviation authority (MAA) is responsible for their oversight. The CAA is aware that Acceptable Means of Compliance 3201(1) to MAA Regulatory Article (RA) 3201(1) states that air traffic services provided by the Ministry of Defence should be provided in accordance with the Radiotelephony Manual (CAP 413) and the RA 3000 series: Air Traffic Management Regulations; these latter Regulations being broadly analogous to the CAA’s MATS Part 1. As such, any military air traffic controller (including any D&D Cell controller) should be aware of the required content of a pilot’s emergency message.
Status
Open
Date
16/08/2023
AAIB Classification
Status
Not Adequate - Open
CAA Update
Date
29/02/2024
The CAA is in the process of modifying the way in which information from a pilot on initial contact, in an emergency situation, can be obtained and recorded. It is our intention to release this in a format that is easily accessible / digestible to not only ATC but also to FIS, AGCS (which is not an air traffic service) and Pilots.
The clarification provided by the AAIB in response to the CAA’s original reply brings in a new dimension (‘This may include information, for example about ground facilities and weather conditions, that are not known to the pilot’) i.e. the presentation of information by ATC to pilots to assist with decision making. Whilst this is outside the scope of the original recommendation, the CAA will give this due consideration.
It should be noted that in the course of an emergency ATS will only deliver information essential for ensuring the best possible outcome.
CAA Update
Date
24/12/2024
The CAA has reviewed the content of CAP 493 MATS Pt 1, CAP 797, Flight Information Service Officer (FISO) Manual and CAP 413 Radiotelephony manual and have determined that they provide sufficient and appropriate content relating to the information that should be exchanged in an emergency situation.
In addition, the CAA will issue a Safety Notice in the new year to highlight the content of CAP 413 to flight schools and training organisations.
The syllabus for AGCS training as per CAP 452 has also been reviewed and the CAA is content that it is adequate to ensure appropriate response to aircraft emergencies within their remit.
AAIB Classification
Date
24/01/2025
Status
Partially Adequate - Open
CAA Update
Date
28/07/2025
The draft CAP 745, Aircraft Emergencies, has introduced a section which includes a number of checklists and it is our intention to include an additional checklist that can be used in a handover situation to obtain relevant information.
The CAA intends to issue a Safety Notice to highlight the relevant content of CAP 413 to flying training organisations and include reference to the new checklists that will be provided in CAP 745.
The CAA expect to be able to provide the next update to this Safety Recommendation by February 2026.
AAIB Classification
Date
25/09/2025
Status
Partially Adequate - Open
CAA Update
Date
26/02/2026
In addition to existing text in CAP 413 ‘Radiotelephony Manual’ we have identified CAP 745 as the appropriate publication in which to promote the types of information that should be obtained and recorded by means of a checklist template. The draft CAP 745 (as shared with you in our last update) as developed by the Flight Safety Committee Working Group has been subject to an initial review by the Airspace/ATM Policy and Oversight teams. The review has concluded that a considerable amount of work will be required before the document could be published as a Civil Aviation Authority publication (CAP). Unfortunately, due to resource and competing priorities I am unable to commit to a publication date. However, I will continue to provide updates periodically.
AAIB Classification
Date
26/03/2026
Status
Partially Adequate - Open
Safety Recommendation: 2023-014
2023-014: It is recommended that the Civil Aviation Authority encourage the use of checklists in air traffic management operations when dealing with abnormal and emergency situations.
Refer to our update for 2023-013 in respect of CAP745 and related checklists.
Adequate - Open
November 2026
AAIB Recommendation transmittal
Date
24/04/2023
Status
Open
CAA Initial Update
Date
20/07/2023
The CAA acknowledges the potential safety benefits from the use of checklists in many (comparatively predictable) circumstances. Such checklists are already widely used by civil air traffic services providers.
The CAA expects civil ANSPs to review the use of checklists (if used) during their internal investigation of accidents and incidents and requires civil air traffic controllers to undertake training in Abnormal and Emergency Situations (ABES). The CAA will consider whether to highlight the benefits of checklists in the context of our nascent work with the UK Flight Safety Committee to update CAP 745 - Aircraft Emergencies: Considerations for air traffic controllers.
The use of checklists within D&D by military air traffic controllers / assistants is a matter for the MAA.
Status
Open
AAIB Classification
Date
16/08/2023
Status
Partially Adequate – Open
CAA Update
Date
29/02/2024
The CAA will consider how to provide the information described in SR 2023-013 in a format that is easily accessible / digestible.
However, is should be recognised that provision of checklists for an infinite set of circumstances/variables is not practicable in terms of production, or use. It is noted that in the 94 seconds that Exeter ATC were in contact with the pilot there would have been insufficient time to locate and utilise checklists relevant to the specific circumstances presented. Nevertheless, the CAA will include a review of scope and content of existing checklists during its routine oversight of ANSPs.
CAA Update
Date
24/12/2024
As advised in our last update, whilst the provision of checklists for an infinite set of circumstances/variables is not practicable, the CAA will continue to encourage use of checklists when it is appropriate and will consider this during its routine oversight of ANSPs. In particular we will encourage the use of a checklist based on information to be provided by pilots which will be supported with additional text and examples of checklists within CAP 745.
AAIB Classification
Date
24/01/2025
Status
Partially Adequate - Open
CAA Update
Date
28/07/2025
Please note our comments against Recommendation 2023-13 in respect of checklists. The CAA expect to be able to provide the next update to this Safety Recommendation by February 2026.
AAIB Classification
Date
25/09/2025
Status
Adequate - Open
CAA Update
Date
26/02/2026
Please note our comments against Recommendation 2023-13 in respect of CAP 745 and related checklists.
AAIB Classification
Date
26/03/2026
Status
Partially Adequate - Open
Safety Recommendation: 2023-015
2023-015: It is recommended that the Civil Aviation Authority determine the effect the D&D Cell’s executive control has on civil ATCOs and inform civil ATCOs of any differences in their responsibilities whilst executive control is exercised.
CAP493 - Manual of Air Traffic Control (MATS) Part 1, twelfth edition dated 31 October 2025 has now been published, incorporating CAP493 SI 2024/01: Distress and Diversion Cell and removing all reference to Executive Control and Operational Control. It now better describes the functions and services offered by the D&D Cell and their interactions with civil ATS units.
Adequate - Open
November 2026
AAIB Recommendation transmittal
Date
24/04/2023
Status
Open
CAA Initial Update
Executive control is an aspect of the D&D Cell’s services which are provided as a State obligation under agreement between the DfT and MOD, not the CAA, and for which the primary delivery is through the D&D cell. Executive control is exclusively a function of the D&D cell, and the CAA does not believe that this concept has a material impact on the operational control of an aircraft, which rests with the unit (whether civilian or military) in contact with the pilot. Where operational control is passed from one unit (whether civilian or military) to another, a full handover should take place.
Notwithstanding the above, the CAA will engage with the MAA to undertake a review of the applicability of the D&D term executive control and to clarify any effect that the D&D controllers believe the use of this term may have on civil air traffic controllers’ responsibilities. This activity will be commenced once the DfT has concluded its review/activity in relation to SRs 2023-16 and 2023-017.
Status
Open
AAIB Classification
Date
16/08/2023
Status
Not Adequate - Open
CAA Update
Date
29/02/2024
The CAA has had multiple discussions with the MAA and the D&D Cell. The anomalies in terminology are now well understood and the relevant military authorities are taking action to amend the terminology used to avoid confusion. The CAA will ensure that this is reflected in the Manual of Air Traffic Services (Part 1) and other relevant material published by the CAA.
CAA Update
Date
24/12/2024
Following discussions, the CAA and the MAA have agreed an amendment to terminology to remove possible confusion. The term ‘Executive control’ will be removed from both the MATS Part 1, when the next edition is published early next year, and the FISO manual and the MAA is in the process of amending its own regulatory documents to reflect the same.
In addition to the above responses the CAA has secured funding and agreement from the D&D Cell, to update a video providing key information for pilots primarily, but also for other sectors of industry, on the assistance that is provided by D&D. We aim to publish that video a.s.a.p. in 2025.
AAIB Classification
Date
24/01/2025
Status
Adequate - Open
CAA Update
Date
28/07/2025
CAP 493 SI 2024/01: Distress and Diversion Cell | UK Civil Aviation Authority dated 19/07/2024 has removed the terms Executive Control and Operational Control and aims to better describe the functions and services offered by the D&D Cell and their interactions with civil ATS units.
The CAA expect to be able to provide the next update to this Safety Recommendation by February 2026.
AAIB Classification
Date
25/09/2025
Status
Adequate - Open
CAA Update
Date
26/02/2026
CAP 493 - Manual of Air Traffic Control (MATS) Part 1, twelfth edition dated 31 October 2025 has now been published, incorporating CAP 493 SI 2024/01: Distress and Diversion Cell and removing all reference to Executive Control and Operational Control. It now better describes the functions and services offered by the D&D Cell and their interactions with civil ATS units.
We would propose to write to you with updates by the end of November 2026, if this is acceptable to the AAIB.
AAIB Classification
Date
26/03/2026
Status
Adequate - Open