Scope of application and affected airports
The regulations apply to air traffic control at the following aerodromes:
- Berlin Brandenburg, Bremen, Dresden, Düsseldorf, Erfurt-Weimar, Frankfurt Main, Hamburg, Hanover, Cologne, Leipzig/Halle, Munich, Münster/Osnabrück, Nuremberg, Saarbrücken and Stuttgart.
Definitions: Important terms
The new procedures define several key terms that clarify low visibility operation:
- Low Visibility Operations (LVO):
Flight operations with a runway visual range (RVR) of less than 550 metres and/or a decision height (DH) of less than 200 feet. - Low Visibility Take-Off (LVTO):
Take-offs with runway visibility below 550 metres. - Guided Take-Off:
Take-off procedure in which the take-off run is additionally supported by instruments (e.g. ILS landing course transmitter). This procedure is used for RVRs between 75 and 125 metres. - Low Visibility Procedures (LVP):
Special procedures at airports to ensure safe operation in restricted visibility. - Visibility level 3:
Taxiway sections with visibility of 300 metres or less, where minimum distances between aircraft and vehicles on the taxiway are maintained.
Procedure for low visibility
The new regulations include several operational adjustments that have been specially developed for restricted visibility:
- ILS protection measures:
- Sensitive and critical areas of the ILS systems must be kept free of vehicles, people and mobile devices.
- Lighting systems:
- Activation of the runway centreline lighting.
- Switching off the glide angle lighting (glide path displays).
- Switching off EFAS (Enhanced Flight Awareness System) at RVRs of ≤ 600 metres.
- Emergency power supply:
- Ensuring the immediate availability of optical and non-optical landing aids, if required.
- Take-off and landing procedures:
- Use of CAT II and CAT III procedures for landings.
- Use of the runways also for Low Visibility Take-Offs (LVTO), provided these are marked accordingly in the Aeronautical Information Publication (AIP).
Operating scenarios and threshold values
The application of the new procedures is based on the runway visual range (RVR) and the main cloud ceiling (HCH):
- Slope visibility ≤ 1000 metres and/or HCH ≤ 300 feet:
- Activation of the emergency power supply.
- Keep the ILS protection zones clear.
- Slope visibility ≤ 600 metres and/or HCH < 200 feet:
- Extended measures, such as deactivating the glide angle lighting and activating special lighting systems.
Security measures and traffic control
Additional safety measures are used in visibility conditions below 300 metres (level 3):
- Ensuring minimum distances between aircraft and vehicles.
- Utilisation of special rolling procedures based on instrument and visual aids.
In these scenarios, air traffic controllers have an increased responsibility to ensure separation and coordination between the aircraft.
Special features for take-offs in low visibility
Guided Take-Off:
With an RVR of 75 to 125 metres, a "guided take-off" is possible, in which the take-off run is additionally supported by instrument signals. This procedure ensures that the pilot can use the runway safely despite extremely limited visibility.
Conclusion
The new DFS regulations improve the safety and efficiency of flight operations in restricted visibility conditions. They make it possible to carry out take-offs and landings even in challenging weather conditions without compromising on safety. Pilots and air traffic controllers must familiarise themselves with the new procedures in order to cope with the complex requirements of low visibility. The changes mark an important step in the optimisation of air traffic control at German airports.
Source references:
NFL (the link requires a subscription to Eisenschmidt)
