Infringement occurrences

While we understand that many pilots are currently unable to fly due to COVID-19 restrictions we aim to continue to release safety education and awareness material to support the GA community with the future return to flying and continue to help promote longer-term safety awareness. To meet that aim we have launched a new series of narratives focusing on infringement occurrences.

 

Class D: Birmingham Control Area

Infringement of Class D – Birmingham Control Area

Date 22 November 2020
Aircraft Category Helicopter
Type of Flight Recreational Flight
Airspace / Class Birmingham CTA / Class D

Air traffic control

The Air Traffic Controller reported seeing an aircraft squawking 7000 enter the Class D CTA-2 near Warwick at 2,000 feet (Figure 1). It appeared to be following the M40 northbound. The aircraft descended to 1,800 feet then made a right turn and tracked eastbound climbing to 2,300 feet. The aircraft eventually turned southeast and left the CTA south of Coventry aerodrome. Multiple attempts to contact the aircraft were made on the frequency with no response.

Map showing where the aircraft entered the Class D CTA-2 near Warwick at 2,000 feet.

Figure 1: The aircraft entered the Class D CTA-2 near Warwick at 2,000 feet.

Pilot

The pilot reported that they had planned a route to fly for their first solo flight as a PPL holder: Leicester Aerodrome – Deenethorpe Aerodrome – Podington racetrack – Olney VRP – Silverstone Circuit – Chipping Warden – Draycote Water VRP – Peter Hall Farm – Nuneaton VRP – Bruntingthorpe Aerodrome – Leicester Aerodrome.

The route had been planned on a VFR moving map on a tablet and transposed on a 1:250,000 VFR chart (figure 2). This was the first time they had used their personal iPad and the GPS stopped working 10 minutes after take-off.

As they had a well-prepared VFR chart, they continued with the flight having never had to rely on GPS previously when flying solo even though they had not flown the southern part of this route south of Northampton before.

After turning at Silverstone they had not noted the time and commented that they must have overshot Chipping Warden but, on seeing motorway, tracked it northwest bound until they could see Draycote Water VRP. By this time, they were beyond the area that was visible on the chart due to the way it was folded. As a result, they did not see the Class D CTA-2 with a base of 1,500 feet. Had they done so, they would have turned 180 degrees and tracked back down the motorway to avoid it.

The pilot added that they did not elect to obtain an air traffic service as they had to use the aircraft registration as their callsign instead of the instructors callsign used during training. In addition, as they routed northbound, they did not utilise the Birmingham Frequency Monitoring Code (FMC) of 0010 and listen out on 123.980MHz as they had not been taught about FMC during their training. At the time of the flight, the pilot reported there to be scattered cloud (3-4 oktas) at about 2,300 feet with good visibility below.

The planned route shown on 1:250:000 VFR chart

Figure 2: The planned route shown on 1:250:000 VFR chart.

Causal factors

The pilot had carried out good planning to carry out their first solo flight after the award of their licence. They had selected prominent geographical features as turning points and in accordance with good practice had planned to use a tablet-based VFR moving map with the paper chart as a back-up.

Shortly after departure, their GPS position failed as they were unaware that the tablet needed to be tethered to their phone as the tablet was not a cellular version.

The pilot lost situational awareness as to their position sometime after their waypoint at Silverstone Race Circuit (figure 3).  Having been unable to locate the next waypoint at Chipping Warden, decided to follow the M40 motorway northbound. Due to the lack of aeronautical information available to the pilot, they entered the Birmingham CTA-2 to the southwest of Warwick at 2,000 feet where the base of controlled airspace is 1,500 feet.

Map showing waypoints

Figure 3: Situational awareness as to their position was lost sometime after the waypoint at Silverstone Race Circuit.

In their pre-flight planning, the pilot applied good Threat and Error Management in marking the route on a paper chart. However, the manner in which the chart had been folded did not leave sufficient airspace and ground features visible to aid navigation. It is essential, as part of pre-flight preparation that you are not only familiar with the equipment functionality and limitations that you intend to rely on in-flight but that contingency measures are suitably prepared.

As the pilot routed northbound from Chipping Warden, as part of the initial plan, good practice would have been to employ the use of a Frequency Monitoring Code (FMC) by selecting the Birmingham frequency of 123.980MHz and then selecting a squawk of 0010 Mode C as their intended route would have taken them close to the Birmingham CTA and well within the notified FMC area of recommended use (see UK AIP EGBG AD2.22 Flight procedures paragraph 7 and the chart at UK AIP ENR 6.80).  The FMC is also annotated on the chart (figure 4). However, it was not incorporated into their plan as, at the time of the occurrence, the pilot was unaware of FMC and their use. Had they been aware, the infringement would have been resolved in a timely manner and navigation assistance offered at an early stage of the occurrence.

FMC annotated on the chart.

Figure 4: FMC annotated on the chart.

The pilot first became uncertain of their position when they missed their turning point at Chipping Warden having not noted their time at Silverstone. However, being unable to locate the aerodrome should have been a trigger to seek assistance from an Air Traffic Service Unit.  A number of options were available including calling D&D on 121.500MHz for either a position fix or a steer to Draycote Water or calling Birmingham on 123.980 MHz for assistance or the LARS unit at Brize Norton on 124.275MHz (offering a service radius of 40NM daily between 0800 hours UTC and 1600 hours UTC).

However, due to the lack of experience of the pilot and then having only ever used an instructor callsign throughout their training rather than their aircraft registration. A lack of confidence in the use of the radio impaired their decision making. It is important for pilots to understand that air traffic control is there to help them and that controllers are used to offering navigational assistance when required.

A chart showing areas of responsibility for the UK LARS units can be found in the UK AIP at ENR6.11. Further details on units participating in the Lower Airspace Radar Services can be found in the UK AIP at ENR 1.6.4 (figure 5).

Lower Airspace Radar Services can be found in the UK AIP at ENR 1.6.4

Figure 5: Lower Airspace Radar Services can be found in the UK AIP at ENR 1.6.4.

Post-flight analysis

This unfortunate occurrence occurred so soon after the pilot had completed their training due to gaps in knowledge, a lack of confidence in operating their radio in flight and lapses in Threat and Error Management.

The pilot is commended for carrying out such detailed post-flight analysis of the occurrence (including the submission of a detailed and honest report), their approach to the factors surrounding the occurrence and for following Just Culture principles.

Focus on

 

Other narratives in this series can be found on the Infringement occurrences page.

Class D: Manchester Control Area

Infringement of Class D – Manchester Control Area

Date 9 December 2020
Aircraft Category Fixed-wing Microlight
Type of Flight Recreational Flight
Airspace / Class Manchester CTA / Class D

Air traffic control

The Manchester radar controller was alerted to an aircraft squawking 7365 a few miles to the northeast of Barton aerodrome. The aircraft was indicating an altitude of 2,400 feet (1). The base of the Manchester CTA is 2,000 feet.

Mode S allowed the aircraft to be identified so the controller was able to contact the Barton Flight Information Service Officer (FISO). After a second call to Barton the aircraft descended.

The aircraft was inside controlled airspace for 3 minutes and 36 seconds before leaving the CTA. No other traffic was affected by the infringement.

The Barton FISO explained that the unit is part of an ADS-B (Automatic Dependent Surveillance–Broadcast) trial. This allows a FISO to offer generic traffic information (TI) to pilots operating within the unit’s designated operational coverage (DOC). Manchester Barton’s DOC is notified as 10NM/3,000 feet. Generic traffic information is given using phrases such as “in your vicinity”.  The FISO could see that the frequency had not been changed to Warton after the aircraft left the unit’s DOC heading north. So issued TI on traffic that was approaching position from the east (see figure 1).

Map showing the position of the aircraft and the approaching traffic

Figure 1: The position of the aircraft is shown as ‘1’ and the approaching traffic as ‘2’

On recovery to Barton, the pilot informed the FISO that they were over Bury (figure 2). The FISO issued TI against an aircraft that was departing the ATZ northbound in a reciprocal direction.

Map showing the position of the aircraft over Bury

Figure 2: Position of the aircraft over Bury

At that point the aircraft was inside the DOC area, and the FISO commented to their assistant that, based on ADS-B altitude, the aircraft appeared high compared with the reported altitude.

The FISO was about to ask the pilot to confirm their altitude and pass updated information on the opposite traffic when the Manchester radar controller called to let them know the traffic was too high. The pilot was informed and carried out a descent out of the CTA to the correct altitude for an overhead join.

Pilot

The pilot was carrying out a VFR sightseeing flight from Barton to Rawtenstall via Bury and Ramsbottom (figure 3).

On the day of the flight, met conditions were good. Visibility was in excess of 10km with some cloud detected at around 4,000 feet and a light and variable surface wind.

Map showing route from Barton to Rawtenstall via Bury and Ramsbottom

Figure 3: Flight from Barton to Rawtenstall via Bury and Ramsbottom

The pilot usually flew with a fellow pilot to supplement each other’s navigation, lookout and communications. On this occasion they were flying solo as their flying partner was unavailable. The pilot was flying the EV97 for the first time in some months. The pilot was using a 1:250,000 VFR chart and a basic version of a VFR moving map application on their mobile phone. This was secured in a mount on the right-hand side of the instrument panel due to the location of the 12V socket and position of the mount. The pilot explained that mounting a moving map is limited to the right-hand side as nothing can be fixed to the canopy. This meant that altitude information was very difficult to see from the left-hand seat. The aircraft was not equipped with either strobes or a beacon and, due to its bare aluminium colour, the pilot was aware that it was harder to see air-to-air than white microlights. The pilot remained on the Barton frequency throughout the flight and was in receipt of a Basic Service from Barton Information.

On the outbound leg, the FISO issued a warning of a much faster aircraft heading in a reciprocal direction. The microlight pilot became extremely anxious that the pilot of the conflicting aircraft would not become visual and all their focus turned to lookout, scanning all around in an unsuccessful attempt to catch sight of the aircraft. Although trimmed for level flight, the microlight had started a gradual climb from Bury to reach an altitude of 2,700 feet at Rawtenstall. Due to their focus on scanning, the pilot had not realised that the aircraft had climbed approximately 1,000 feet above their intended cruising altitude. On turning back towards Barton, and not realising they had climbed so much, a quick glance at the altimeter told the pilot that the aircraft was at *,800 feet. Having intended to fly at around 1,700 feet, the pilot mistakenly took this reading to be 1,800 feet. It was really 2,800 feet. The pilot started a gradually descent of 300 feet to what they thought was 1,500 feet, but was actually 2,500ft. This altitude was maintained the rest of the way back to the Barton overhead.

The pilot made two position reports en-route at this altitude of “Overhead Bury, one thousand five hundred feet” and “Half a mile north of Swinton Interchange at one thousand five hundred feet”. Overhead Barton, the FISO asked the pilot to check their altitude at which point they realised that the needle on the altimeter was pointing towards “2” not “1”. The pilot apologised whilst commencing a steep descent into the Barton circuit. The pilot added that a smaller aircraft or one with less performance in their proximity, “as often happens around Barton”, would not have caused them so much concern. But the warning of a larger aircraft travelling at a much higher speed triggered a serious worry about the risk of a mid-air collision had affected their concentration.

Figure 4 shows an approximate representation of the flight profile.

Map showing an approximate representation of the flight profile.

Figure 4: Approximate representation of the flight profile.

After the event the pilot analysed the occurrence, and noted a number of factors that led to them not noticing the higher altitude:

  • Better conspicuity would lessen the stress of not being seen by other aircraft thereby reducing their focus on external scan and allowing some division of attention between lookout and instrumentation.
  • A check of the basic version of the VFR moving map technology led them to note that their version did not offer warnings of possible vertical infringements.
  • The mobile phone was positioned so far away from the pilot that they could not get an independent altitude check from that equipment.
  • In previously flown aircraft, they recall seeing an additional display within the altimeter showing the altitude in numbers.

Causal factors

The pilot had planned to carry out a sightseeing flight to the north of Barton. The decision to use a 1:250,000 chart, allowing greater definition of the route features, was good based on the aircraft’s speed and the relatively short distance of the flight (approximately 15NM from Barton aerodrome). The use of a chart for navigation was supported by a VFR moving map.

However, in becoming distracted in trying to visually acquire conflicting traffic, an inadvertent climb resulted in the aircraft eventually reaching 1,200 feet higher than the intended cruising altitude.

The pilot was subject to confirmation bias. They knew they wanted to fly at or around 1,500 feet and the small needle on the altimeter pointed to 800 feet. In the pilots mind they expected to be at or around 800 feet. Having not flown the EV97 solo for some time, they were not surprised to have reached a slightly higher altitude by a few hundred feet.

Nothing in their plan or the small needle on the altimeter was to indicate that they were over 1,000 feet higher than intended. The confirmation bias could have been broken by one, or both of the following:

  • The pilot normally flew with another pilot who has a tablet device with a ‘full’ version of a VFR moving map application. Had the pilot has such a device/version, even as a back-up to their using the 1:250,000 VFR chart, they would have had the benefit of a larger display which would have provided them with alerts as they climbed up to 2,800 feet with the Manchester TMA being above them at 3,500 feet. It would also have provided an alert on the inbound leg as they approached the Manchester CTA some 300 feet above the base altitude and then again as the CTA base stepped down to 2,000 feet.
    These warnings are shown when the trajectory, both horizontal and vertical, would take an aircraft into a volume of airspace. An onscreen warning is often accompanied by an audible alert, the form of which depends on the type of airspace, and a thick border may be drawn on the map accompanied by large coloured arrows to highlight which piece of airspace is associated with the warning.
    The CAA and safety partners actively encourage all pilots to incorporate the use of moving maps in both pre-flight planning and during flight. On this occasion, the pilot had not applied active Threat and Error Management in relation to their equipment in respect of the size and position of the display and the functionality of the ‘basic’ version of the application. In addition, the lack of options for the position of the mount may have played a part in accessing data from the moving map.
  • Had the pilot elected to obtain an air traffic service from the local LARS unit at Warton on 129.530MHz the chain of events may have been broken. On initial contact the pilot may have noticed the error when passing their details to the controller or, when they told Warton Radar that they were at 1,800 feet, Warton Radar would have noted an error in the Mode C when carrying out the verification and validation process during identification for a radar service. The Barton DOC is notified as 10NM/3,000 feet. When leaving the DOC area northbound, the pilot would have been better served getting a service from Warton.

The pilot became task saturated. While trying to visually acquire the aircraft for which they received information they failed to note an inadvertent altitude change. The pilot cannot be criticised for being risk aware and concerned of the developing situation. However, the use of an electronic conspicuity device on a larger display and/or the provision of an air traffic service are effective mitigations of mid-air collision. With mitigations in place capacity can be increased and stress levels reduced.

Having operated the EV97 for some time some skill fade may also have been a contributory factor.

Post-flight analysis

The pilot is commended for carrying out such detailed post-flight analysis of the occurrence (including the submission of a detailed and honest report), their approach to the factors surrounding the occurrence and for following Just Culture principles.

In addition they immediately engaged the services of a flight instructor to obtain remedial refresher training to ensure that issues could be addressed and rectified.

Focus on

(1) Please note that Mode A code and Mode C pressure-altitude have not been verified.

 

Other narratives in this series can be found on the Infringement occurrences page.

Class D and Class A: Gatwick Control Area and London Terminal Control Area

Infringement of Class D and Class A airspace – Gatwick Control Area and London Terminal Control Area

Date 6 August 2020
Aircraft Category Fixed-wing Microlight
Type of Flight Recreational Flight
Airspace/Class Gatwick CTA / Class D and
London Terminal Control Area (LTMA) / Class A

The Air Traffic Controller

The Air Traffic Controller reported receiving a Controlled Airspace Infringement Tool (CAIT) alert of an aircraft squawking 7000 indicating 1,800 feet briefly enter the Gatwick Control Area (CTA). Some 13 minutes later, the aircraft was seen to enter the LTMA in the vicinity of the Mayfield VOR/DME (MAY) at 2,900 feet. Whilst the controller was planning what action was required to ensure separation was maintained with an aircraft inbound to Gatwick Airport, the unknown aircraft descended below controlled airspace.

These infringements did not result in a Loss of Separation due to the significant reduction of commercial traffic at Gatwick associated with COVID-19. But under normal traffic conditions, due to the location of the infringements, this event may have caused a safety event and considerable workload for commercial pilots and controllers.

The Pilot

The pilot reported that the flight was planned to fly from Headcorn to Deanland and return to Headcorn later. The cloud base at the time was approximately 1,600 feet and the visibility was good. Despite the good visibility, the lower than expected cloud base did cause some distraction.

The aircraft was equipped with, and the pilot was operating, a MODE S transponder and squawking 7000 with MODE C. Whilst aware of the benefits of moving map technology, the pilot had chosen not to use one as they did not want to become over reliant on it to avoid degradation of conventional navigation skills.

The pilot had planned the flight, and was using a 1:250, 000 VFR chart, although no route line was drawn on the chart. Flying a heading of 240 degrees the pilot misidentified Bewl Water as Darwell Reservoir resulting in them being north of their intended track. This led to being too far to the west when trying to visually locate Deanland, the destination aerodrome. Having failed to locate Deanland, the pilot decided to return to Headcorn and turned left onto a reciprocal track when approximately 3NM southeast of Haywards Heath. When the cloud base improved, a climb was initiated but as they were further west than they thought, the pilot infringed the LTMA as they were still under the area where the base is 2,500 feet.

Meteorology

The TAF at the time of the Infringement forecast an improving cloud base after 0700 hours UTC:

EGKK 060458Z 0606/0712 20007KT 9999 BKN010
TEMPO 0606/0607 BKN007
PROB30 TEMPO 0606/0607 6000 -RADZ BKN004
BECMG 0607/0610 SCT030
PROB30 0702/0707 8000=

The METARS as issued:

0750 EGKK 060750Z 19007KT 160V230 9999 BKN013 20/17 Q1007=
0820 EGKK 060820Z 21006KT 160V240 9999 BKN012 20/17 Q1018=
0850 EGKK 060850Z 22007KT 190V250 9999 BKN015 21/17 Q1018=

Causal Factors

The pilot had planned to carry out a direct flight to Deanland.  Based on the aircraft’s speed and the relatively short distance of the flight the decision to fly using 1:250,000 chart was sound and greater definition of route features were available.  However, in selecting an initial incorrect heading, the outbound track was offset to the north of the water feature of Bewl Water (A in Figure 1).  The pilot knew that they wanted to be north of Darwell Reservoir (B in Figure 1) and once airborne from Headcorn and visual with a large water feature, the pilot became subject to confirmation bias.

In the pilots mind they expected to see a water feature to the south. Because the pilot was familiar with the area and had flown the route many times, they knew that they needed to be just to the north of Darwell Reservoir. The sight of a body of water to the left of the route meant that the pilot’s expectations were confirmed, and the sensitivity of the error detection mechanism was reduced at a time when mental capacity was also taken up with the distraction of lower-than-expected cloud. By keeping Bewl Water to their left the pilot was destined to infringe the Gatwick CTA.

Figure 1 Bewl Water and Danwell Reservoir

Figure 1 Bewl Water and Darwell Reservoir

The pilot’s planning was complacent due to the number of times the route had been flown and their knowledge of the area:

  • No attempt was made to obtain the upper winds by using the MetForm 214 or other APPS.
  • A line was not drawn on a chart between Headcorn and Deanland.
  • A Navigational Plan/ Log (PLOG) was not constructed for the flight.

As a result of the 2,000 feet wind on the day (approximately 180 degrees /10 knots), the heading flown gave a ground track (red line in figure 2) of approximately 250 degrees.  The heading required to fly a direct track from Lashenden to Deanland was approximately 224 degrees (purple line in figure 2). With a lowering cloud base en route, the pilot became distracted from the navigation task and the effects of the initial heading error were not challenged.

Figure 2 Ground and direct tracks

Figure 2 Ground and direct tracks

The pilot’s normal method of navigation was to use dead reckoning techniques. Had the pilot used a moving map, even just as a back-up, they would have quickly identified that the aircraft was significantly off track and that Bewl Water was not Darwell Reservoir.  In addition, as the pilot approached the Gatwick CTA, with correct configuration, a visual and aural warning could have been provided. These warnings are triggered when the horizontal and vertical trajectory would take an aircraft into a volume of controlled airspace. An onscreen warning is often accompanied by an audible alert, the form of which depends on the type of airspace, and a thick border may be drawn on the map accompanied by large coloured arrows to highlight which piece of airspace is associated with the warning. The CAA and safety partners actively encourage all pilots to incorporate the use of moving maps in both pre-flight planning and during flight.

At no time did the pilot believe they were lost. They became uncertain of their location when they were unable to locate Deanland which the pilot commented is not an easy aerodrome to locate due to the surrounding landscape. However, being unable to locate the aerodrome should have been a trigger to seek assistance from an Air Traffic Service Unit.  A number of options were available including calling D&D on 121.500MHz for either a position fix or a steer to Deanland; calling Gatwick on 126.825MHz or Farnborough LARS (East) on 123.225MHz.

A chart showing areas of responsibility for the UK LARS units can be found in the UK AIP at ENR6.11. In the case of Farnborough LARS, there are annotations on the VFR Charts (see figure 3). A last barrier could have been the use of the Frequency Monitoring Code (FMC) for Gatwick.  Although the intended track of the flight would have been 2NM to the south of the published area for the Gatwick FMC (7012 and 126.825MHz), the first, brief, infringement, would have been acted upon by the Gatwick Director which may have acted as a trigger to the pilot that they were some 8.5NM north of track.

Figure 3 Farnborough LARS East

Figure 3 Farnborough LARS East

Focus on

 

Other narratives in this series can be found on the Infringement occurrences page

Class A: Cotswold Control Area

Infringement of Class A airspace – Cotswold Control Area

Date 20 August 2020
Aircraft Category Fixed-wing Microlight
Type of Flight Instructional Flight
Airspace/Class Cotswold CTA / Class A

Met information

At the time of the infringement the local QNH both at Brize Norton and Fairford was 1003 hPa. The cloud was BKN (5-7 oktas) at 4,800 feet and the forecast 5,000 feet wind on the UK Low-level Spot Wind Chart (Form 214) was 190/30.

The Air Traffic Controller

The Air Traffic Controller reported observing an unknown aircraft squawking 7000 indicating FL071 (7,100 feet based on 1013 hPa) enter the lateral confines of L9 in the vicinity of the IFR reporting point GAVGO, which is near Swindon. The aircraft remained in L9 for a period of 9 minutes 32 seconds. The aircraft was later observed to change to a Brize Norton conspicuity squawk (3737) but the Brize Norton Air Traffic Service Unit was unable to establish contact with the pilot.

The Pilot

The pilot reported that the training flight was being conducted in very local and familiar airspace. Navigation was being carried out using a 1:250K VFR chart with no GPS/Moving Map. The initial part of the flight was conducted under a layer of cloud (reported to be at 4000-5000 feet) but training was made difficult due to turbulence. The aircraft was turned south to remain clear of the Cotswold CTA with a base of FL065 and climbed above the cloud. Due to strong winds aloft, the aircraft was not positioned as far south an anticipated and with repeated turns the aircraft was ‘blown back’ into L9. The pilot found it difficult to determining their position due to only intermittent sight of the surface as a result of operating above cloud; they felt that the infringement was increased due to the low QNH.

Causal Factors/Findings

1:250,000 VFR charts have a vertical limit of airspace of 5000 feet ALT. The decision to climb to an altitude where no airspace information was available in the cockpit was the result of the instructor being  inadequately prepared for this flight. Figure 1 compares the information available on the 1,250,000 with the 1:500,000 chart. Figure 2 shows the warning annotated on all 1:250, 000 charts to remind users of the vertical limits.

1,250,000 vs 1:500,000 chart

Figure 1: 1,250,000 vs 1:500,000 chart

1:250, 000 chart warning to remind users of the vertical limits

Figure 2: 1:250, 000 chart warning to remind users of the vertical limits

The infringement lasted 9 minutes 32 seconds. Figure 3A shows the area on a 1:500,000 chart. Figure 3B shows the same area on the chart available to the instructor in the cockpit.

Area shown on a 1:500,000 chart

Figure 3A: Area shown on a 1:500,000 chart

 

Area on the chart available to the instructor

Figure 3B: Area on the chart available to the instructor

When it became clear that prevailing weather conditions required a change to the plan after departure the instructor should have either abandoned the flight or revised their plan. To mitigate against risks associated with over confidence/complacency their revised plan needed decisions based on aeronautical information available in flight, rather than perceived knowledge.

The instructor chose to operate without a Moving Map. The CAA and safety partners actively encourage all pilots to incorporate the use of Moving Maps in both pre-flight planning and in-flight.  When properly configured and used effectively, a visual and aural airspace warning would have been given alerting the pilot of their proximity to controlled airspace.

The instructor failed to recognise the Threats associated with cloud base and strong winds aloft. This resulted in the pilot losing situational awareness of the aircraft’s position. Once above cloud and unable to maintain positional awareness, the pilot made an Error in not requesting an air traffic service (ATS) from the local Lower Airspace Radar Service unit; Brize Norton is just 12NM from the location of the infringement.

At 1003 hPa, the QNH was not uncharacteristically low but it meant that the aircraft was some 300 feet higher on the local QNH when adjusted for the Standard Altimeter Setting (the correct pressure datum of the Cotswold CTA). However, the aircraft was still flown some 600 feet higher than the base of controlled airspace. Had the Instructor had the correct chart available and having stated they were aware of the Class A airspace with a base of FL065, they should have incorporated a maximum altitude of 6,000 feet on the QNH of 1003 hPa into their plan to remain below controlled airspace. This, in line with Take 2 guidance, would have ensured they were operating below the CTA and have a buffer of 200 feet to allow the management of the Threats associated with turbulence or student handling error.

When the pilot eventually displayed a Brize Norton SSR code the unit was unable to establish 2-way communications. In the first instance a pilot should only select the conspicuity code (3737) when instructed to do so or in accordance with local procedures.  Had the pilot intended to display the Frequency Monitoring Code (Listening squawk) the code selected should have been 3727 with the relevant frequency selected (124.275 MHz).

Instructors often lower the volume of the comms panel/radio during instructional flights as constant R/T can distract the student and impede in-cockpit talk between instructor and student.   It is not uncommon in occurrence involving instructional flights for ATC not to be able to establish communication with the pilot for this reason.

Focus on

Class D: Stansted Control Area 4 and Luton Control Area 1

Infringement of Class D airspace – Stansted Control Area 4 and Luton Control Area 1

Date 26 September 2020
Aircraft Category Fixed-wing Aeroplane
Type of Flight Recreational Flight
Airspace/Class Stansted & Luton CTA / Class D

The Air Traffic Controller

The Air Traffic Controller reported that they had traffic on a right-base for Runway 25 at London Luton Airport descending to 3,000 feet. A radar contact was seen to climb into controlled airspace south of Royston passing 2,600 feet before stopping the climb at 3,000 feet on an approximate track of 250o. Traffic information was passed to the Luton arrival aircraft and it was turned onto a shorter final to avoid the infringing aircraft. At this point the unknown aircraft selected 0013 squawk and the controller was able to ascertain their callsign and get 2-way communication with him. The pilot informed the controller they were leaving controlled airspace to the north which they subsequently did. The aircraft was then identified and given a service as per the pilot’s request. The Luton arrival was then re-vectored and completed a safe approach to land.

The Pilot

The pilot reported carrying out a recreational flight from Duxford to Cornwall via Wing (west southwest of Leighton Buzzard) to route to the north of the Luton Control Zone. The route was planned to be flown at 3,000 feet to remain below the CTAs with a lowest base of 3,500 feet. The plan was to climb straight ahead to 3,000 feet on a heading of 251o after departure from Runway 24 (Figure 1).

Figure 1

Figure 1

On the morning of the flight there was a strong northerly wind flow down the east side of the UK. The associated TAF were as follows:

  • Stansted: 300/14, PROB 40 TEMPO 2606/2609 32018G28
  • Luton: 300/14, TEMPO 2606/2706 33018G28.
  • The forecast 2,000 feet wind at 5230N 00E was 340/35 (35 knots at 90o to the planned track)

Just before departure an aircraft called Duxford Information to state they would be conducting visual circuits at Fowlmere (2.5NM west southwest of Duxford). On lining up for departure the pilot was informed of the traffic at Fowlmere and the surface wind “being something like 310/16”.

On climb out the pilot encountered the most vigorous turbulence that they could recall flying in for many years. They elected to hold runway heading as best they could to climb straight ahead out of the ATZ without turning right to the track of 251o degrees to enable them to remain clear of Fowlmere (blue line in Figure 2); the passenger was asked to look out for the Fowlmere circuit traffic. Given the turbulence, the pilot elected to climb at best rate of climb speed, which was approximately 80 knots, with the aim of getting into smoother air as soon as possible.

Once clear of Fowlmere, the pilot called Duxford to leave their frequency, changed to Luton Radar on 129.550 MHz and then selected the Luton Frequency Monitoring Code (FMC) of 0013. With the long nose of the aircraft, forward visibility is limited when climbing steeply; unfortunately, that meant fewer visual cues as to actual track were available to the pilot. As the aircraft approached 3,000 feet the pilot asked the passenger to pass them their Moving Map tablet that had been running since departure. The pilot was just noting they had had flown to the left of the airspace line (magenta line in Figure 2) when Luton Radar called to advise that they were indicating at 2,800 feet and was advised immediate descent to below 2,500 feet. Realising their error, the pilot responded that they were descending and turning north to head out of the Stansted CTA as quickly as possible.

Figure 2

Figure 2

ATC aspect

The airspace and track where the aircraft infringed is routinely used by Luton and Stansted traffic. This incident took place when the traffic was light and therefore the consequences of the infringement was minimal. Following agreement with the pilot of the arriving aircraft the controller re-positioned the aircraft and ensured minimum separation was achieved between the two aircraft However, in normal traffic levels with a continuous stream of arrivals the ability to reposition the aircraft without any impact on subsequent arrivals is unlikely. The workload increase for pilot and controller is significant under these circumstances with safety remaining paramount. One infringement of only a few minutes can result in many minutes of delay to operators, with additional fuel burn and emission also a consideration.

Causal Factors/Findings

The pilot carried out detailed and effective planning in route selection to remain outside controlled airspace and included the use of FMC along the route. In addition, they were equipped with a Moving Map which was intended to be used actively en-route. They also recognised the Threat associated with dual operations at Duxford/Fowlmere.

However, a minor change to the plan moments prior to departure allowed the introduction of lapses in wider Threat and Error Management. The decision to fly further south in strong cross winds and to climb at a higher rate resulted in the aircraft’s track being affected greater over a shorter distance the aircraft drifting further south of track than had been anticipated. The pilot, unaware of their ground track due to reduced forward visibility associated with the aircraft’s attitude then lost situational awareness and extended beyond that required to avoid the traffic flying circuits to the north of Fowlmere. By the time the aircraft was south abeam the Runway 25 threshold at Fowlmere, it was 1.2NM south and passing 1,500 feet. In addition, had the pilot identified that routing to the south of Fowlmere would take them closer to the Class D CTAs they may have identified the increased value to using the Moving Map. This would have enabled them to regain situational awareness lost through the aircraft’s attitude. The pilot could have either turned right back onto track or stop their climb below 2,500 feet to remain below the CTA. However, the pilot was faced with several distracting factors from their original plan and their capacity was rapidly being used in handling the aircraft in extremely turbulent conditions whilst considering the traffic at Fowlmere and the wellbeing of their passenger.

In their wider plan, the pilot had considered the Take 2 aspect to remain clear of controlled airspace but that was not revised following the amended plan to deviate to the south of Fowlmere and thereby fly close to the CTA. Had the pilot only climbed to, for example 2,300 feet, until closer to Royston, the infringement could also have been avoided. This probably did not enter the pilots thought process as the focus was on climbing out of the turbulence, avoiding the Fowlmere visual circuit, and selecting the next radio frequency and FMC.

Notwithstanding the lapses in Threat and Error Management, the pilot’s initial plan was good and incorporated several key measures to prevent airspace Infringements:

  1. Comprehensive planning including airspace avoidance and meteorology;
  2. Use of a Moving Map; and
  3. Use of an FMC.

That decision to use an FMC enabled early intervention by air traffic control to assist the pilot and resolve the situation promptly. In addition, detailed post-occurrence analysis and open and detailed reporting by the pilot enabled lessons to be identified to avoid a recurrence.

Focus on

Class D: Birmingham Control Area 1

Infringement of Class D airspace – Birmingham Control Area 1

Date 24 August 2020
Aircraft Category Fixed-wing Aeroplane
Type of Flight Recreational Flight
Airspace/Class Birmingham CTA-1 / Class D

The Air Traffic Controller

The Air Traffic Controller reported that Runway 33 was in use at Birmingham with one aircraft shortly to depart. The controller was alerted to an unknown aircraft entering CTA-1 indicating 1,900 feet and squawking 0010 (the Birmingham Frequency Monitoring Code). Using MODE S derived information, the controller made a transmission to the pilot and asked them to descend immediately. The departing aircraft was instructed to depart straight ahead to maintain separation to the west of the infringing aircraft. The pilot stated they were mistakenly inside the CTA and descended; the aircraft was identified, issued with a discrete squawk and, once clear of the CTA, offered a Basic Service. Sometime later the aircraft climbed again into the CTA to 1,600 feet and, when informed of the climb, the pilot carried out an immediate descent.

The Pilot

The pilot was prompt to submit a comprehensive report to the CAA. They reported that the aircraft had recently had a complete avionics refit with all original radios and navigation equipment replaced with fully integrated GPS/NAV/COM/MFD equipment, Electronic Flight Instruments and an autopilot. Initial flights post-installation were carried out for the pilot to become familiar with the basic instrumentation; the subject flight was planned for a longer distance to test the autopilot. The pilot openly admitted that the new avionics were not the reason for the infringement but “sloppy planning” carried out on the morning of the flight was a contributory factor. In that planning session, the pilot had ‘rubber banded’ the magenta line on the Moving Map. The red line in Figure 1 shows the route planned and that flown. Having taken the northern route around Birmingham many times, after departure the pilot usually routed at 1,900 feet to Lichfield Disused, then west between Cosford and Wolverhampton Aerodrome Traffic Zones taking them below the Birmingham CTA-3 with a base of 3,500 feet (blue line in Figure 1).

On the day of the infringement, the pilot followed their plan that took them west through, and not below, the similarly shaped but lower CTA-1 which has a base of 1,500 feet. On hearing their callsign broadcast by the Birmingham air traffic controller, the pilot’s first instinct was to disengage the autopilot and follow the requests of the controller. They then accepted a basic service and a discrete squawk. The second climb was thought to have occurred as the pilot wouldn’t normally fly as low as 1,500 feet over the built up areas to the west of Aldridge towards Walsall; they reported that they were most likely conscious of a lack of clearance with the terrain which, in that area, lies between 450 feet and 500 feet amsl. The rest of this flight, and the return flight home was uneventful.

The pilot added that on any other day they were sure they would have noticed the mistake of their plan in the air because the route was clearly wrong. However, distraction caused by focussing on the new avionics drawing more of their attention led them to miss the planning error.

After the occurrence, the pilot elected to take time with an instructor who was familiar with the new avionics to carry out some more familiarisation training and navigation practise.

Airspace Infringement of Class D Airspace - Birmingham Control Area 1 : Figure 1

Figure 1

Causal Factors/Findings

The pilot is to be commended by their openness and post-occurrence actions. This occurrence demonstrated the benefit of using a Frequency Monitoring Code (FMC); the pilot reported that they use them whenever they are available in the areas in which they are flying. This positive approach to, and correct use of, the FMC allowed the initial infringement to be resolved promptly by the controller and pilot. In addition, the pilot correctly operated their transponder with MODE C (ALT) alerting the controller to the infringement; had MODE C not been operated, the controller would have been correct to have ‘deemed’ the aircraft to be below the CTA. Had that been the case, the risk of a mid-air collision or the infringing aircraft being affected by wake turbulence would have been heightened.

Poor planning and a failure to double check the route and associate altitudes of the airspace resulted in confirmation bias that they were able to fly at 1,900 feet. In the planning phase, by creating a back-up on a paper chart, you are often notice additional information/details that you don’t always notice on your Moving Map display.

Even though the pilot was flying with a Moving Map, it is not known why there was no response to the alert. It is possible that the confirmation bias led the pilot to dismiss the alert without noting its subject. When properly configured and used, an airspace warning would have been given the pilot a timely alert of their proximity to controlled airspace.

In summary, the pilot did not carry out sufficiently detailed pre-flight planning which, combined with confirmation bias and distraction from overly focussing on new avionics, resulted in their flying into Class D controlled airspace without an air traffic control clearance. However, textbook use of an FMC allowed the infringement to be resolved in a prompt manner.

Despite some errors associated with Human Factors, the pilot has embraced a Just Culture and identified the benefits associated with completing the appropriate refresher training which was carried out with a Flight Instructor.

Focus on


Controller’s stories

A series of controller’s stories from NATS

Mark Davenport, an air traffic controller at Swanwick centre, talks about his experience with airspace infringements. Airspace Infringement Series: A controller’s story… (20 May 2019)

Brian Ringrose is an air traffic controller at Swanwick centre. He talks about his experience looking after airspace around Gatwick. Airspace infringement series: A controller’s story (12 April 2019)

Amanda Rhodes is an air traffic controller at Swanwick Centre.  She talks about her experience looking after airspace around Luton Airport. Airspace Infringement Series: A controller’s story (22 March 2019)

 

Keep reading

Infringement updates

NEW Birmingham CTA occurrence

Infringement avoidance

Learn more

Denied airspace access?

Online reporting form