What's Happening?
Pilots operating under Instrument Flight Rules (IFR) can request a 'VFR-on-top' clearance from Air Traffic Control (ATC) to fly at Visual Flight Rules (VFR) altitudes. This clearance allows pilots to select an altitude of their choice, subject to ATC restrictions,
when flying in VFR weather conditions. The primary purpose is to enable pilots to remain above, below, or between cloud layers, or in areas free of meteorological obstructions, thereby avoiding prolonged periods of flying through solid Instrument Meteorological Conditions (IMC). According to the FAA's Instrument Flying Handbook (IFH), this option is available to pilots on IFR flight plans who are in VFR weather. While utilizing this clearance, pilots must still adhere to their cleared lateral route, maintain communication with ATC, and comply with all other IFR requirements, including minimum IFR altitudes and position reporting. This clearance essentially modifies the vertical aspect of their flight plan, not the lateral.
Why It's Important?
The 'VFR-on-top' clearance significantly impacts pilot comfort and operational flexibility during IFR flights. By allowing pilots to fly in clear air, it can reduce fatigue associated with extended periods in IMC, improve visibility, and potentially lessen air sickness for passengers due to reduced turbulence. This flexibility is crucial for maintaining pilot well-being and passenger comfort, which are vital aspects of flight safety and efficiency. The ability to choose an optimal altitude within VFR conditions, while still under IFR control, provides a balance between the structured safety of IFR and the visual advantages of VFR. This practice underscores the adaptability of air traffic regulations to accommodate varying weather conditions and pilot preferences, ultimately contributing to a more efficient and comfortable air travel experience within the U.S. airspace system.
What's Next?
Pilots utilizing 'VFR-on-top' clearances are expected to continue advising ATC of any altitude changes to ensure accurate traffic information. They must also remain compliant with VFR visibility and distance-from-cloud criteria as prescribed in FAR 91.155, and adhere to appropriate VFR altitudes as per FAR 91.159. While ATC may provide traffic advisories, the pilot in command retains the responsibility to see and avoid other aircraft when operating in VFR conditions. This clearance is not permitted in Class A airspace. The ongoing use and understanding of this clearance will continue to be a standard practice for IFR-rated pilots seeking to optimize their flight conditions when VFR weather allows, ensuring a blend of safety and operational preference.
Beyond the Headlines
The distinction between 'VFR-on-top' and 'VFR over-the-top' highlights a nuanced aspect of aviation regulations that can be easily confused. 'VFR-on-top' is an IFR clearance allowing VFR altitudes, whereas 'VFR over-the-top' is a VFR operation maintaining cloud clearance requirements above an overcast layer. This subtle difference underscores the complexity of aviation rules and the critical importance of precise terminology for pilot safety and regulatory compliance. The ability to transition between IFR and VFR conditions, even within a single flight plan, reflects a sophisticated regulatory framework designed to maximize safety while offering operational flexibility. This approach acknowledges the dynamic nature of weather and the need for pilots to make informed decisions that prioritize safety and efficiency, demonstrating a deeper commitment to adaptable air traffic management.
