Low-Visibility Procedures (LVP)

Updated at: 2025-12-01 11:21
Low-Visibility Procedures (LVP) are special airport and air traffic control measures activated when visibility or cloud base drops below defined limits, allowing aircraft to continue operating safely during fog, heavy rain, snow, or low cloud.<\/b>

1. Definition of Low-Visibility Procedures (LVP)

Low-Visibility Procedures (LVP) are standardized airport and air traffic control (ATC) procedures that apply when runway visual range (RVR) or cloud base fall below pre-set thresholds. They are published in the Aeronautical Information Publication (AIP) for each aerodrome and describe how ground movements, approaches, landings, and departures are controlled in low-visibility conditions.
In practice, LVP change how the airport is used: taxi routes are restricted, runway protection becomes stricter, lighting patterns may change, and aircraft spacing is increased. For pilots, LVP primarily affect taxi instructions, approach minima, and the need for precise compliance with clearances and stop bars (red lights across taxiways).
LVP are usually linked to instrument landing system (ILS) categories, such as Category II (CAT II) and Category III (CAT III), which allow approaches and landings with very low decision heights and RVR values.

2. Purpose of Low-Visibility Procedures

The main purpose of Low-Visibility Procedures is to maintain safety when visibility is reduced, while still allowing a controlled level of traffic to operate. Without LVP, airports would often have to close or significantly reduce operations during fog, heavy precipitation, or very low cloud ceilings.
Key objectives of LVP are:
  • Protect the runway and ILS sensitive areas so that landing and departing aircraft receive an undisturbed radio signal.
  • Prevent runway incursions by using stop bars, tighter ATC control, and simplified taxi routes.
  • Reduce the risk of ground collisions between aircraft and vehicles when visibility on taxiways and aprons is poor.
  • Ensure consistent pilot and controller actions through pre-published, standardized procedures.
For a student pilot, the key idea is that LVP create an extra safety buffer: everyone follows stricter rules so that aircraft can still take off, land, and taxi with minimal risk, even when you can see only a short distance ahead.

3. Use of LVP in Aviation

3.1 When LVP are activated

Airports activate Low-Visibility Procedures when measured visibility or cloud base reaches specific trigger values. These values are published for each aerodrome, but commonly include:
  • Runway Visual Range (RVR) falls below a set value, for example 600 m or 550 m, depending on the airport.
  • Cloud base (ceiling) drops below a defined height, especially for precision approaches.
  • Forecast conditions indicate that low visibility will occur shortly, so the airport prepares in advance.
The tower or approach controller will usually announce LVP in force on the Automatic Terminal Information Service (ATIS) and may remind pilots on the radio, for example: "Low-Visibility Procedures in operation."

3.2 How LVP affect air traffic control

When LVP are in force, air traffic controllers apply stricter rules to protect aircraft and maintain safe separation. Typical changes include:
  • Runway protection: No aircraft or vehicle is allowed to enter the runway or ILS critical area without explicit clearance. Controllers avoid issuing line-up clearances too early.
  • Use of stop bars: Red stop-bar lights at runway holding points remain on and are only switched off when ATC clears an aircraft to cross or enter the runway.
  • Increased spacing: Arrival and departure spacing may be increased to allow more time for vacating the runway and for radar identification.
  • Reduced taxi complexity: Controllers may use simpler, shorter taxi routes and restrict certain taxiways to avoid confusion.
For the student pilot, this means you should expect very precise taxi clearances, more hold-short instructions, and the requirement to stop at lit stop bars unless ATC specifically clears you to proceed and the stop bar is turned off.

3.3 How LVP affect pilots

Pilots must adapt both flight planning and cockpit procedures when LVP are in force. Main effects are:
  • Approach minima: Only aircraft and crews approved for low-visibility operations (e.g. CAT II or CAT III) can land when RVR is very low. Others must divert or hold until conditions improve.
  • Taxi discipline: Pilots must taxi slowly, follow the cleared route exactly, and stop at all stop bars and holding points unless cleared otherwise.
  • Checklists and briefings: Additional or extended briefings are required for low-visibility take-offs and approaches, including go-around and missed approach planning.
  • Lighting and equipment: Use of all available external lights, anti-collision lights, and internal aids such as moving maps or surface radar displays, if installed.
Student pilots operating at smaller, non-precision aerodromes may not see full LVP systems, but the same principles apply: stricter control of runway access, careful taxiing, and adherence to higher approach minima when visibility is poor.

4. Operational Considerations for Student Pilots

4.1 Pre-flight planning and briefing

Before flying to or from an aerodrome where Low-Visibility Procedures may be used, pilots should prepare for the possibility that LVP will be in force on arrival or departure.
Essential pre-flight planning steps include:
  1. Check weather forecasts and reports (METAR, TAF, trend forecasts) for visibility, RVR, and cloud base.
  2. Review the aerodrome chart and AIP for LVP information, including ILS categories, taxiway restrictions, and holding points.
  3. Confirm your aircraft and pilot privileges, including whether you are allowed to conduct instrument approaches and under which minima.
  4. Plan alternates with better forecast visibility, especially if your destination often experiences fog.
  5. Brief passengers that delays, holds, or diversions are more likely in low visibility.
In a training environment, instructors will often use potential LVP conditions as a teaching opportunity to practice decision-making, diversion planning, and conservative weather minima.

4.2 Taxiing during LVP

Ground movement is one of the highest-risk phases during low visibility. Student pilots must be especially careful to avoid runway incursions and taxiway deviations.
Recommended taxi procedures under LVP or very low visibility are:
  1. Obtain and write down the full taxi clearance before moving. Clarify any unclear instruction immediately.
  2. Use all available charts, including an airport diagram, and orient it correctly with the aircraft heading.
  3. Taxi slowly, allowing time to identify signs, lights, and markings. Adjust speed to the actual visibility.
  4. Follow centerline lights or markings if available, especially on main taxiways.
  5. Stop at every lit stop bar or holding point unless ATC has specifically cleared you to cross and the stop bar is extinguished.
  6. Cross-check outside references with instruments such as heading, GPS ground track, or a moving map, if installed.
  7. If in doubt, stop and ask ATC for clarification or progressive taxi instructions.
Progressive taxi instructions mean that ATC gives you step-by-step guidance, for example: "Taxi straight ahead, then right on Alpha, I will call your next turn." This is especially useful for pilots who are not familiar with the aerodrome layout.

4.3 Approaches and landings in low visibility

Approaches under LVP conditions require strict adherence to published minima and missed approach procedures. Student pilots usually operate under visual flight rules (VFR) or basic instrument privileges and should not attempt low-visibility approaches beyond their training and licensing.
Key approach considerations in low visibility are:
  1. Know your minima: Identify decision altitude/height (DA/DH) or minimum descent altitude (MDA) and required visibility before starting the approach.
  2. Stabilize early: Ensure the aircraft is fully configured, on speed, and on the correct vertical and lateral path well before minima.
  3. Use all available aids: ILS, VOR, GPS, approach lights, and PAPI/VASI should all be used to confirm position.
  4. Apply a clear go-around policy: If you do not see the required visual references at or before minima, execute a missed approach without hesitation.
  5. After landing: Vacate the runway as instructed, then stop and confirm taxi instructions if unsure about the route in low visibility.
At some large aerodromes, automatic landings (autoland) are used by suitably equipped aircraft and trained crews in CAT III conditions. Student pilots in light aircraft are normally not involved in these operations but should understand that traffic flows and holding patterns may be affected by such operations.

4.4 Take-offs in low visibility

Low-visibility take-offs are subject to minimum RVR requirements and often require additional equipment such as runway centerline lights, high-intensity runway edge lights, and specific aircraft instruments. For student pilots, the focus should be on conservative decision-making and staying well above absolute minima.
Typical low-visibility take-off considerations:
  1. Check take-off minima: Confirm that reported RVR or visibility meets or exceeds the published minima for your runway and aircraft type.
  2. Use the correct runway: LVP may limit departures to a specific runway equipped for low-visibility operations.
  3. Align carefully: Use centerline lights or markings to ensure correct runway alignment before applying take-off power.
  4. Maintain centerline: Use visual cues and, if available, instruments such as heading indicator and flight director to stay on the centerline during the take-off roll.
  5. Be prepared to reject: In case of doubt about runway alignment, instrument indications, or aircraft performance, be ready to reject the take-off while there is sufficient runway remaining.

5. Examples of Low-Visibility Procedures in Practice

Short, realistic examples can help you understand how Low-Visibility Procedures affect day-to-day flying.

5.1 Example: LVP arrival at a major airport

An instrument-rated crew is arriving at a large international airport in fog. The ATIS states: "Low-Visibility Procedures in operation. ILS CAT III available runway 26." The aircraft flies an ILS CAT III approach with autoland. After landing, the crew vacates the runway and stops at the first taxiway stop bar. Ground control then gives a precise taxi route, and the stop bar is switched off only when it is safe to proceed.

5.2 Example: Student pilot diversion due to LVP

A student pilot on a cross-country flight under visual flight rules plans to land at an aerodrome where morning fog is common. En route, the pilot hears on the radio that Low-Visibility Procedures are in force and that only instrument approaches are being accepted. Visibility is below the pilot’s personal VFR minima. The student pilot decides to divert to the planned alternate aerodrome with better visibility, demonstrating correct decision-making in low-visibility conditions.

5.3 Example: Progressive taxi in low visibility

At a regional airport with LVP active, a pilot unfamiliar with the aerodrome requests progressive taxi from ground control after landing. ATC responds with short, step-by-step taxi instructions and confirms each turn. The pilot follows the centerline lights, stops at every holding point, and reads back each instruction, reducing the risk of getting lost or entering the runway by mistake.

6. Summary for Student Pilots

Low-Visibility Procedures (LVP) are a set of airport and ATC measures that keep operations safe when visibility or cloud base is very low. They tighten control of runway and taxiway use, protect sensitive navigation equipment, and set clear rules for approaches and departures.
For student pilots, the key points are: understand what LVP means on the ATIS, know your own licence and aircraft limitations, plan alternates, taxi slowly and precisely, respect all holding points and stop bars, and never hesitate to ask ATC for clarification or progressive taxi instructions. Conservative decisions in low visibility are an essential part of safe flying.