Jaspal Singh Bahra

C G BUTLER – SENIOR CORONER FOR BUCKINGHAMSHIRE 

INVESTIGATION INTO THE DEATHS OF JASPAL SINGH BAHRA, SAAVAN SINGH 
MUNDAE, MICHAEL LEONARD GREEN & THANH TRUNG NGUYEN 

CIVIL AVIATION AUTHORITY RESPONSE TO A REPORT ON ACTION TO PREVENT 
OTHER DEATHS PURSUANT TO REGULATION 29 OF THE CORONERS 
(INVESTIGATIONS) REGULATIONS 2013 

The Civil Aviation Authority (CAA) has considered carefully the report of the Senior Coroner 
to prevent future deaths and its response to the concerns raised is set out below: 

A) ‘See & Avoid’ 

i) 

Introduction 

At  present,  there  is  no  single  alternative  available  that  comprehensively 
addresses the limitations inherent in the use of ‘see and avoid’ techniques.  

The  CAA  anticipates  that  the  further  development  and  deployment  of 
universally-compatible electronic conspicuity devices will aid in mitigation the 
risk of future mid-air collisions occurring in Class G (uncontrolled) airspace. As 
such, this is an area in which the CAA has invested and will continue to invest 
significant resources.  

However,  pending  such  further  advancement  and  subsequent  adoption,  the 
CAA  continues  to  address  the  associated  risk  by  ensuring  that  pilots  are 
cognisant  of  the  limitations  of  ‘see  and  avoid’;  reviewing  reports  of  airprox 
incidents identifying causal or contributory factors; collaborating with industry 
stakeholders through the Mid-Air Collision Programme and recommending or 
acting where appropriate to mitigate the risk of such incidents occurring. 

ii) 

Regulatory Framework 

The European Aviation Safety Agency (EASA) was established as an agency 
of  the  European  Union  (EU).  In  2003,  EASA  assumed  the  responsibility  for 
certain International Civil Aviation Organisation (ICAO) obligations on behalf of 
EU Members States. These obligations include policies for personnel licensing, 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 rules  of  the  air  and  operations.  The  EU  Basic  Regulation  established  EASA 
competence in these areas and implementing rules have since been published 
setting  out  the  requirements.  Commission  Regulation  (EU)  No.  1178/2011 
concerns  the  regulation of  aircrew  and provides  certain  requirements for the 
training  and  licencing  of  pilots.  Annex  1  to  the  EU  Aircrew  Regulations  is 
referred to Part-FCL. ‘Acceptable Means of Compliance’ (AMC) and ‘Guidance 
Material’ are published to support each  element of the regulations. AMC1 to 
FCL.210 details the syllabus that instructors have to deliver, so that a student 
pilot  may  build  the  necessary  competence  and  skills  in  a  structured  and 
achievable manner. 

Student pilots are required to complete a training course at a Declared Training 
Organisation  or  an  Approved  Training  Organisation.  The  course  includes 
theoretical knowledge and flight instruction appropriate to the privileges applied 
for.  The  standard  format  for  a  course  is  a  series  of  exercises,  starting  from 
basic principles, to allow the student pilot to achieve an initial solo standard. 
The  student  is  required  to  consolidate  these  skills  before  moving  on  to 
navigation, landing at other aerodromes and introduction into radio navigation 
and instrument flight. Effective look out technique training is incorporated from 
a  very  early  stage  in  pilot  training.  The  Acceptable  Means  of  Compliance  to 
FCL.210 states that ‘each of the exercises involves the need for the applicant 
to be aware of the needs of good airmanship and look-out, which should be 
emphasised at all times’.1 

The importance of maintaining an effective visual lookout is reinforced through 
CAA publications. In May 2019, the CAA published the second edition of the 
‘Skyway Code’,2 which is intended to provide pilots involved in non-commercial 
and flight training operations with practical guidance on the operational, safety 
and regulatory issues relevant to their flying. Its primary focus is safe aircraft 
operations  and  the  safe  use  of  airspace.  It  is  oriented  towards  Visual  Flight 
Rules  (VFR)  flight  and  provides  guidance  on  the  rules  for  the  prevention  of 
collisions; precautionary measures that pilots can take; techniques for effective 
visual  scanning;  the  limitations  of  ‘see  and  avoid’  and  available  means  of 
ensuring  electronic  or  visual  conspicuity.  The  CAA  intends  that  the  Skyway 
Code  will  be  reviewed  annually  to  ensure  it  reflects  the  latest  regulatory 
requirements and best aviation practice. 

iii) 

UK AIRPROX Board 

The  United  Kingdom  Airprox  Board  (UKAB)  is  the  UK’s  focal  point  for 
investigating and reporting the circumstances, causes and risk of collision for 
all airprox occurrences3 in UK airspace. The UKAB conducts investigations into 
airprox events, reporting directly to Chief Executive of the CAA and the Director 

1 AMC1 FCL.210.A PPL(A) – Experience Requirements and Crediting. 
2 CAP 1535, Skyway Code, Version 2 <http://publicapps.caa.co.uk/modalapplication.aspx?appid=11&mode=detail&id=7920>. 
3 An ‘airprox’ is defined as a situation in which, in the opinion of a pilot or air traffic services personnel, the distance between 
aircraft  as  well  as  their  relative  positions  and  speed  have  been  such  that  the  safety  of  the  aircraft  involved  may  have  been 
compromised. 

 
 
 
 
 
 
 
                                                           
 Military  Aviation  Authority  (MAA)  as  a  quasi-independent  endeavour  beyond 
the day-to-day oversight activity of those entities.  

The  UKAB  focuses  on  enhancing  air  safety.  It  provides  a  mechanism  for 
feedback  and  follow-up  of  airprox-related  insights  and  recommendations 
regarding  the  efficacy  of  airspace  regulation  and  the  factors  that  have 
influenced the performance of pilots and controllers. The sole objective of the 
UKAB is to assess occurrences in the interests of enhancing air safety; it does 
not apportion blame or liability. 

The  UKAB  website  details  specific  airprox  events  together  with  ‘lessons 
identified’ and actions flowing from UKAB Safety Recommendations. The Pilots 
and controllers involved in the airprox event each receive their own copy of the 
UKAB’s  final  report  which  sets  out  what  happened  and  why.    Safety 
Recommendations  are  made  where  appropriate  to  reduce  the  risk  of 
recurrence. 

The UKAB publishes an annual report, which includes an analysis of UK airprox 
numbers,  rates  and  trends,  to  raise  awareness  and  understanding  in  the 
aviation community. Airprox Reports are one method of monitoring instances 
in  which  aviation  safety  may  have  been  compromised.  Together  with 
mandatory  occurrence  reports  and  voluntary  reports  made to  the  CAA,  they 
ensure that incidents or occurrences are reported and can be learned from. 

iv) 

Mid-Air Collision (MAC) Programme 

Mitigating against the risk of a future mid-air collision is a complex and long-
term  challenge.  The  CAA’s  current  MAC  Programme  aims  to  reduce  by 
regulatory  action  the  risk  of  a  mid-air  collision.  The  programme  pursues 
improvements in systems, cultures, and operational processes. 

The  MAC  programme  stakeholders  work  with  the  UKAB,  UK  Flight  Safety 
Committee,  CAA  UAS  Programme,  Military  Aviation  Authority  and  industry 
stakeholders  to  better  understand  and  assess  risk  and  identify  effective  and 
collaborative  mitigation.  This  coordinated  effort  in  turn  ensures  that  the  UK 
meets the European Plan for Aviation Safety (EPAS) requirement for Member 
States to address the risk of mid-air collisions in their safety plans. 

The  current  MAC  Programme  Board  provides  the  CAA’s  Safety  &  Airspace 
Regulation  Group  (‘SARG’)  with  a  data  observatory  function,  where  key 
indicators,  trend  analysis  data  and  causal  factor  information  is  received, 
monitored and considered. Potential intervention actions are identified by the 
Programme Board and tasked for action. This data and coordination function 
will continue into the foreseeable future in compliance with EPAS requirements. 

Among other measures, the MAC Programme will continue to: 

a.  manage data on MAC events and use this evidence to steer action and 

mitigation strategies with industry collaboration; 

 
 
 
 
 
 
 
 b.  encourage  the  further  development  and  deployment  of  conspicuity 

devices which are interoperable, practical and affordable; and 

c.  contribute to the update and accessibility of the recently published CAP 

1535 The Skyway Code to act as a guide to airmanship. 

v) 

Conclusion 

Pilots are trained to be proficient in, and to understand the limitations of, ‘see 
and avoid’ techniques as part of their basic training requirements. In addition, 
there  are  measures  in  place  to  ensure  that  accidents,  incidents  and  ‘near 
misses’  in  uncontrolled  airspace,  are  reported  and  dealt  with  appropriately. 
Where  appropriate,  such  occurrences  may  be  investigated  to  determine 
whether regulatory action may be required. 

The Regulation 28 report to prevent future deaths has provided an opportunity 
to review the approach to ‘see and avoid’ techniques and to give consideration 
as to how best to mitigate the risk of collisions in Class G airspace. The issue 
is a complex and long-term challenge. The CAA will continue to analyse the 
findings  and  recommendations  of  the  UKAB,  and  utilise  the  outcomes 
promoted by the MAC Programme to enhance safety in this area.  

B) Carbon Monoxide Exposure 

The potential for carbon monoxide contamination in small aircraft (fixed or rotary wing) 
is addressed through regulations that concern the design, maintenance and operation 
of such aircraft. 

i)  

Aircraft Design 

The European Aviation Safety Agency (EASA) has oversight of the design of 
the aircraft involved in this accident. EASA promulgates design requirements 
(‘codes’)  CS-23  for  ‘Small  Light  Aeroplanes’  and  CS-VLR  for  ‘Very  Light 
Rotorcraft’,  which  contain  specific  requirements  on  cockpit  contamination 
preventative measures. Any change to those requirements would need to be 
brought about by EASA. The codes address the required levels of ventilation, 
the maximum acceptable CO content in the cockpit and the design of heating 
systems (notably exhaust-related heat exchangers) with a view to preventing 
CO contamination in the cockpit. The codes do not require CO detectors to be 
fitted  as  part  of  the  design.  Similar  design  requirements  exist  in  the  United 
States, which is the primary source of general aviation aircraft types.   

ii)  

Maintenance 

Maintenance (Continuing  Airworthiness) requirements  and recommendations 
in  the  UK  provide  that  aircraft  exhaust  systems  are  to  be  inspected  in 
accordance  with  the  manufacturer’s  instructions,  the  requirements  of  which 
may  vary  from  physical  inspection  to  physical  inspection  with  partial  dis-
assembly, internal inspection and pressure testing.  In the UK, there are two 
publications of specific relevance to this topic:  

 
 
 
 
 
 CAA Publication (CAP) 562 ‘Civil Aircraft Airworthiness Information and 
Procedures’ 

This  publication  includes  Leaflet  B-190  ‘CO  contamination’,  which 
provides generic expectations for the maintenance-related measures to 
minimise the  likelihood of  such occurrences.   It addresses  the  nature 
and  effects  of  carbon  monoxide,  the  causes  of  contamination,  the 
importance  of 
for 
contamination.  

inspections  and  means  of 

routine 

testing 

CAA Publication CAP 747 ‘Mandatory Requirements for Airworthiness’  

This publication contains a related Generic Requirement, ‘GR No. 11’, 
covering  potential  CO  contamination from  combustion heaters,  which 
are only fitted to a relatively small number of light aircraft. GR No. 11 
addresses servicing and overhaul requirements intended to detect CO 
contamination 

Also,  as  a  result  of  specific  in-service  instances,  some  manufacturers  have 
issued  type-specific  information  that  has  been  mandated  by  the  responsible 
aviation authorities in the form of ‘Airworthiness Directives’.     

The new pan-European light aircraft maintenance requirements that are being 
proposed for adoption later this year (Part M Light) are expected to contain a 
requirement in the Minimum Inspection Programme (MIP) to “[i]nspect Cabin 
Heating Heat Exchanger for improper condition and function. For exhaust heat 
exchanger check CO-Carbon monoxide concentration.” 

iii)  

Operation 

In the UK, there are a series of pamphlets (‘Safety Sense’ leaflets) providing 
guidance  to  aircraft  owners/operators  on  a  variety  of  subjects.   The  ‘Winter 
Flying’  Safety  Sense  Leaflet  contains  information  on  the  use  of  ‘spot-type’ 
passive  indicators.  Such  devices  are  small,  widely-available  and  relatively 
inexpensive. They can be attached to a wall or panel in the cockpit and do not 
need to be professionally installed. 

There are a range of active CO detectors available that use audible, visible or 
vibration warnings when pre-determined CO levels are exceeded.  These have 
the  notable  advantage  of  actively  engaging  the  pilot’s  attention  and  are 
accordingly more likely to be more effective than the ‘spot-type indicators’.   

CO  detectors  may  be  fitted  to  UK-registered  aircraft  as  ‘standard  changes’ 
under the provisions of CS-STAN (for EASA aircraft) and CAP 1419 (for non-
EASA aircraft). This removes the need for direct authority involvement, allowing 
equipment to be installed without the associated time and costs.   

CO detectors are not mandated for general aviation aircraft, as from an initial 
design viewpoint, the requirements for the certification of the aircraft are such 
that the system design should minimise the likelihood of CO contamination, but 
the  maintenance  of  sometimes  notably  highly-utilised  airframes  and/or  their 
ageing systems means that contamination can occasionally take place.  The 
more  widespread  use  of  CO  detectors  is  thus  currently  down  to  the 
pilot/owner’s discretion.   

 
 
 iv)  

Conclusion 

The Regulation 28 report to prevent future deaths has provided an opportunity 
to review available material on CO contamination avoidance. Notwithstanding 
the measures already in place and those expected in the near future, the CAA 
will  consider  the  merits  of  an  additional  information  on  best  practice  CO 
contamination avoidance, in a ‘Safety Notice’ publication.  To this end, the CAA 
will  consult  with  members  of  the  relevant  stakeholder  forum,  the  AOPA 
Maintenance Working Group,  in making  this  decision  by  the  end  of the  third 
quarter  of  2019. If  a  decision  be  made  to  publish  a  Safety  Notice,  this  is 
expected to take place by the end of 2019.