# Flight Learnings

## Relationship of Time and Longitude

Maps and Charts

The mean sun travels at a constant rate, covering 360° of arc in 24 hours. The mean sun transits the same meridian twice in 24 hours. The following relationships exists between time and arc: Time/Arc 24 hours/360° 1 hour/15° 4 minutes/1° 1 minute/15′ Local time is the time at one particular meridian. Since the sun […]

## Time

Maps and Charts

In celestial navigation, navigators determine the aircraft’s position by observing the celestial bodies. The apparent position of these bodies changes with time. Therefore, determining the aircraft’s position relies on timing the observation exactly. Time is measured by the rotation of the earth and the resulting apparent motions of the celestial bodies. This section considers several […]

## The Earth (Part Two)

Maps and Charts

Longitude The latitude of a point can be shown as 20° N or 20° S of the equator, but there is no way of knowing whether one point is east or west of another. This difficulty is resolved by use of the other component of the coordinate system, longitude, which is the measurement of this […]

## The Earth (Part One)

Maps and Charts

Shape and Size For most navigational purposes, the earth is assumed to be a perfect sphere, although in reality it is not. Inspection of the earth’s crust reveals there is a height variation of approximately 12 miles from the top of the tallest mountain to the bottom of the deepest point in the ocean. A […]

## Basic Terms

Maps and Charts

Basic to the study of navigation is an understanding of certain terms that could be called the dimensions of navigation. The navigator uses these dimensions of position, direction, distance, altitude, and time as basic references. A clear understanding of these dimensions as they relate to navigation is necessary to provide the navigator with a means […]

## Other Cockpit Information System Features

Information Systems

Electronic Checklists Some systems are capable of presenting checklists that appear in the aircraft operating manual on the MFD. The MFD in Figure 5-23 depicts a pretaxi checklist while the aircraft is parked on the ramp. In some cases, checklists presented on an MFD are approved for use as primary aircraft checklists. It is important […]

## Fuel Management Systems

Information Systems

A fuel management system can help you make the fuel calculations needed for in-flight decisions about potential routing, fuel stops, and diversions. A fuel management system offers the advantage of precise fuel calculations based on time, distance, winds, and fuel flow measured by other aircraft systems. When a route has been programmed into the FMS, the […]

## Traffic Data Systems

Information Systems

A traffic data system is designed to help you visually acquire and remain aware of nearby aircraft that pose potential collision threats. All traffic data systems provide aural alerts when the aircraft comes within a certain distance of any other detected aircraft. Traffic data systems coupled with MFDs can provide visual representations of surrounding traffic. […]