25 May 2005
Study contiguous areas that may contribute flow and include any such
flow in the design (UFC 3-230-15FA).
Temporary ponding on the airfield following the design storm event shall
not result in ponding within 75 ft from the edges of airfield pavements
Storm sewers shall be a minimum of 12 in. diameter on Army and Air
Force airfields, and a minimum of 15 in. diameter on Navy and Marine projects.
AIR NAVAIDS. This section discusses the function of the various visual
and electronic NAVAID components and the appropriate requirements of an RFP for a
project that includes NAVAIDS.
Meteorologic Conditions. NAVAIDS are installed and operated to
provide visual or electronic guidance to pilots during ground movements and aircraft
flight operations over a range of meteorologic conditions. The meteorologic conditions
and the rules that apply under those conditions are defined in paragraphs 3-9.1.1
Visual Meteorological Conditions (VMC): When visibility and ceiling
conditions exceed minimum criteria for visual aircraft operations.
Visual Flight Rules (VFR): Rules that govern the procedures for
conducting flight under visual conditions.
Instrument Meteorological Conditions (IMC): When visibility and ceiling
conditions are below VMC but exceed minimum criteria for instrument operations.
Instrument Flight Rules (IFR): Rules that govern the procedures for
conducting instrument flight.
NAVAID Types and Purpose. Electronic NAVAIDS are needed to provide
initial positioning and direction information to an aircraft approaching an airport and
runway, particularly in IMC conditions. Visual landing aids provide direction to pilots
during VMC conditions and also ensure a timely and safe transition from the instrument
phase to the visual phase of a landing approach during IMC conditions. In addition,
visual NAVAIDS provide information and directions to taxiing aircraft once on the
Pavement marking can be considered a visual NAVAID and is discussed in paragraph
Airfield Operational Categories. The visual and electronic NAVAIDS
required for an airfield are based upon the operational category of the airfield facility.