| Home | Privacy | Contact |

Pilot's Handbook of Aeronautical Knowledge
Aviation Weather Services

Electronic Flight Displays (EFD)
Multi-Function Display (MFD) Weather

| First | Previous | Next | Last |

Pilot's Handbook of Aeronautical Knowledge



Table of Contents

Chapter 1, Introduction To Flying
Chapter 2, Aircraft Structure
Chapter 3, Principles of Flight
Chapter 4, Aerodynamics of Flight
Chapter 5, Flight Controls
Chapter 6, Aircraft Systems
Chapter 7, Flight Instruments
Chapter 8, Flight Manuals and Other Documents
Chapter 9, Weight and Balance
Chapter 10, Aircraft Performance
Chapter 11, Weather Theory
Chapter 12, Aviation Weather Services
Chapter 13, Airport Operation
Chapter 14, Airspace
Chapter 15, Navigation
Chapter 16, Aeromedical Factors
Chapter 17, Aeronautical Decision Making




NEXRAD radar display.
Figure 12-23. NEXRAD radar display.

NEXRAD radar is mutually exclusive of Topographic
( T O P O ) , T E R R A I N a n d S T O RMS C O P E . When
NEXRAD is turned on, TOPO, TERRAIN, and
STORMSCOPE are turned off because the colors used to
display intensities are very similar.

Lightning information is available to assist when NEXRAD
is enabled. This presents a more vivid picture of the weather
in the surrounding area.

In addition to utilizing the soft keys to activate the NEXRAD
display, the pilot also has the option of setting the desired
range. It is possible to zoom in on a specific area of the
display in order to gain a more detailed picture of the radar
display. [Figure 12-24]

NEXRAD Abnormalities
Although NEXRAD is a compilation of stations across
the country, there can be abnormalities associated with the
system. Some of the abnormalities are listed below.
• Ground clutter
• Strobes and spurious radar data
• Sun strobes, when the radar antenna points directly at
the sun
• Interference from buildings or mountains, which may
cause shadows
• Military aircraft which deploy metallic dust and may
reflect the radar signature

NEXRAD Limitations
In addition to the abnormalities listed, the NEXRAD system
does have some specific limitations.

Base Reflectivity
The NEXRAD base reflectivity does not provide adequate
information from which to determine cloud layers or type
of precipitation with respect to hail versus rain. Therefore, a
pilot may mistake rain for hail.

In addition, the base reflectivity is sampled at the minimum
antenna elevation angle. With this minimum angle, an
individual site cannot depict high altitude storms directly
over the station. This will leave an area of null coverage if
an adjacent site does not also cover the affected area.