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Preventing infringements of Luton Controlled Airspace
This infringement update is the twenty fourth in a series of narratives focusing on airspace infringements in the UK. This article highlights the risk of airspace infringements around Luton Control Areas (CTA) and Control Zone (CTR) and provides guidance and suggestions to assist in reducing the risk.
In 2019, there were a total of 44 airspace infringements of Luton Controlled airspace; 23 infringements of the Luton CTR and 21 of the Luton CTA. In the first 8 months of 2020, including the period of the COVID-19 restrictions on General Aviation, there have been 24 infringements (15 of the CTR and 9 of the CTA).
Any infringement within the controlled airspace requires the Luton radar controllers to establish a minimum of 3NM lateral or, when altitude information is available, 3,000 feet vertical separation which results in an increase in workload for pilots and controllers as well as delays to arriving and departing aircraft. The impact of an infringing aircraft will depend upon the location and can impact on both Stansted and Luton airports simultaneously.
The Class D Luton CTR extends from the surface to 3,500 feet with the nine parts of Luton Class D CTA ranging from 2,500 feet (at the lowest part) to 5,500 feet (at its highest). The London Terminal Control Area (TMA) is contiguous with the CTA in some areas. VFR flights in the Luton CTR/CTA will be given routeing instructions and/or altitude restrictions in order to integrate VFR flights with other traffic; a 1.5NM wide VFR lane is also depicted on the 1:500K VFR chart. Pilots should anticipate clearance and routeing instructions via Entry/Exit Lanes and as such should be planned for transits of the CTR; prior to entering controlled airspace, as clearance, from Luton radar, is required to transit this lane. (FIGURES 1 and 2)
The number of aerodromes (including disused ones) and those with ATZ, privates landing sites, navigational aids and Visual Reference Points marked on the chart can make the airspace appear complex, before the various airspace classifications, levels, frequencies and Frequency Monitoring Codes (FMC) are included. Identifying the ‘Threats’ in the planning stage for flights in this area will assist with solutions to ensure infringements do not occur.
Visual Reference Points
Seven Visual Reference Points (VRP) are published to support the planning of flights through the CTR via the Entry & Exit Lane (known as North & South Lane) as follows:
a. The village of Pirton is on the edge of the CTR and lies at the northern edge of the North Lane. The VRP is the church in the village (FIGURE 3).
b. The VRP at Offley lays on the A505 west of Hitchin and 3.5NM northeast of the airport. (FIGURE 3). The VRP is the bridge over the A505. This VRP is often used as a clearance limit as part of the VFR CTR transit clearance as a holding area to establish visual contact with aircraft to allow integration with at Luton Airport.
c. The VRP at Hyde lays less than 2NM south of the airport. The VRP is the railway bridge at East Hyde and is easily identifiable to the northeast of the sewage farm/water treatment works. (FIGURE 4)
d. Kimpton Hall VRP lays to the south of the village of Kimpton and 3.25NM southeast of the airport. (FIGURE 4).
The VRPs at Hyde and Kimpton Hall are often used as a clearance limit as part of the VFR CTR transit clearance as a holding area to establish visual contact with aircraft to allow integration with traffic at Luton Airport.
e. The final 3 VRPs all relate to motorway Junctions and are shown in FIGURE 5. One, the M1 Junction 9 lies inside the CTR and 3.7nm southwest of the airport; it is the figure of 8 junction on the straight piece of motorway mod way between Hemel Hempstead and Luton. The other 2, M1 Junction 8 and A1(M) Junction 4 both lie outside the CTR and are easily identifiable point to set as your clearance limit if you are not in receipt of a clearance to enter controlled airspace.
M1 Junction 8 is to the east of Hemel Hempstead and is the entry point for the south lane. The final VRP at A1(M) Junction 4 lays between Hatfield and Welwyn Garden City and is the confluence of several major roads.
Infringements of the Luton CTR and CTA-2
The area north of Bovingdon VOR (BNN) is an area where infringements of the Luton CTR and CTA-2 (base 2,500 feet) have occurred (FIGURE 6), mainly by instructors who have become distracted from monitoring their height or exact position when teaching. Infringements of the London Control Area (LTMA) where the base is 2,500 feet immediately overhead BNN have also been reported. Even with restrictions on GA flying in the first half the year there were 6 infringements in the first 6 months of 2020 in these areas.
Westbound/Eastbound to the South of the Luton CTR
The use of BNN and BPK can assist with remaining south of the CTR but if planning by landmarks or features reference to Chesham (Southwest of BNN) – Hemel Hempstead – St. Albans – Welwyn Garden City is an option.
In the area under to the west of Luton CTR there were 9 infringements within CTA-2/3/4/8/9 within the first 6 months of 2020.
Southbound/Northbound to the West of the Luton CTR
For those who wish to route in the gap between the Halton ATZ (active 0900-2000 or SS + 15 (1 hr earlier in Summer)) and the Luton CTR it is essential that pilots must plan and identify prominent features to assist in the ‘Threat & Error Management’ of navigational errors.
If routing southbound from Milton Keynes following the railway line to Leighton Buzzard and then towards Tring lakes to the east of Wilstone Reservoir will keep pilots out of the Halton ATZ and west of the Luton CTR. Although the Milton Keynes to Tring railway line/Grand Union Canal/A4251 junction is suggested it needs to be highlighted that at Tring all these 3-line features will eventually lead you into the south western corner of the Luton CTR. With ‘Error Management’ in mind the best solution would be to track towards Chesham after Tring. (FIGURE 7)
Southbound/Northbound to the East of the Luton CTR
CTA-1 (base 2,500 feet) lies to the east of the Luton CTR; the use of BPK and Barkway (BKY) can be useful if radio navigation aids are required to assist with remaining east of the CTR. Alternatively, planning a route with reference to Hertford – east of Stevenage – Letchworth Garden City/Baldock at the end of the A1(M) is an option to be considered in the planning phase. (FIGURE 8) Similarly, the area north of Brookman’s Park (BPK) can also result in an infringement of the TMA, Luton CTA-1 or parts of the Stansted CTR and CTA.
Flying North of the Luton CTR
The M1 remains an easy feature to identify from the air but with so many junctions close to CTA boundaries (FIGURE 9), it is vital to recognise where airspace steps down towards the Luton CTR. The boundary of the CTA-6 where the base is 4,500 feet (just north of junction 13, with a railway line passing nearby) southeast of Milton Keynes, south of Cranfield airport should be recorded in any flight plan and identified as a potential ‘Threat’ in the planning stage. The A421 is a good visual boundary feature as it routes towards Bedford.
Similarly, CTA-5 boundary base reduces to 3500 feet near junction 12 for Toddington. However, pilots often confuse the junction with Toddington Services which is one mile further south or the ‘dumbbell’ junction with the A5 at Houghton Regis, north of Dunstable and a mile north of the Luton CTR boundary.
Tracking north of the CTR can be planned by reference to Royston – north of Letchworth Garden City – Toddington Services on the M1 – Leighton Buzzard.
|When operating west of the red line the Luton FMC (0013) should be used including monitoring of Luton Radar on 129.550MHz.
When operating east of the red line the Stansted FMC (7013) should be used including monitoring of Essex Radar on 120.625MHz.
With all these suggested routes, if you are not in receipt of an air traffic service, good airmanship is to squawk 0013 and monitor the Luton Radar frequency of 129.550MHz rather than squawking 7000 or 2000. However, it is important in your pre-flight planning to know where the boundary lies between using the Luton FMC of 0013 and that for Stansted of 7013 and monitoring the Essex Radar frequency of 120.625MHz. The chart in the UK AIP at ENR6.80 and in AIC YELLOW 006/2020 shows that when crossing the line between Royston and BPK you should be changing FMC and frequencies depending on your direction of flight; failure to do so will result on relays in resolving airspace infringements. There have been recent occurrences where pilots have infringed the Stansted CTR/CTA to the east of Ware, tracking northeast or southeast, but still using the Luton FMC.
Preventing an airspace infringement
The Airspace & Safety Initiative website provides extensive advice on how to avoid the risk of infringing airspace. Pilots are strongly encouraged to:
Use a Moving Map which will provide a profile along your planned route showing the controlled airspace boundary. When flying in proximity to Luton controlled airspace, and if able to, Take 2.
Obtain a service from Farnborough on LARS North: 132.800MHz.
Use a Frequency Monitor Code (FMC). If you do not want to obtain a service from ATC use a FMC appropriate to the direction of flight (rather than squawking 7000/2000). FMCs have proven to prevent infringements and reduce the severity of such occurrences.
|Farnborough LARS North||132.800MHz|
|Luton Radar||129.550MHz||FMC: 0013|
|Essex Radar (Stansted)||120.625MHz||FMC: 7013|
Use the correct QNH. Obtain the Luton QNH from the ATIS (120.580MHz) or monitor the Luton frequency (129.550MHz). The Luton ATIS is also available on 01582 395225 if the METAR is required prior to departing, especially from a private site close to the CTR or under the Luton CTAs.
Make a Detailed Plan. Build in your climb and descent points when planning your route. Know what VRPs look like and what airspace lies above them or close by.
If necessary, request a clearance. If for any reason a climb is required above the base of the CTA, then a clearance must be obtained from Luton Radar before climbing. If in doubt, of the base of CAS or the boundary contact Luton Radar for assistance.