What is TC in Aviation? (True Course)

True Course, often abbreviated as TC, is an essential term in aviation that refers to the actual direction of an aircraft’s path over the ground, without any adjustments for wind or other factors. It represents the angle between the aircraft’s position at the starting point and its position at the destination, measured in degrees relative to true north. True Course is a critical concept in flight planning and navigation, allowing pilots to determine the most efficient and direct path to their destination.

When an aircraft is flying at a constant altitude without any wind influences, True Course is synonymous with the track made good, which is the path actually covered over the ground. However, in real-world scenarios, wind can significantly affect an aircraft’s direction and speed, leading to a drift away from the intended track. Therefore, to counteract this drift and maintain the planned True Course, pilots must calculate and adjust their headings based on wind conditions.

In the next sections, we will explore the importance of True Course in aviation, its calculation methods, and how it relates to other navigation concepts.

Calculating True Course

Calculating True Course requires consideration of various factors, such as wind speed, wind direction, magnetic variation, and groundspeed. By taking these factors into account, pilots can determine the most accurate heading to follow in order to reach their destination.

To calculate True Course, pilots follow a series of steps:

Step 1: Determine Magnetic Heading

The first step is to determine the magnetic heading, which is the angle between the aircraft’s nose and magnetic north. Pilots can obtain this information from the aircraft’s compass or by using navigational aids such as a magnetic heading indicator.

It’s important to note that magnetic north is not aligned with true north due to the Earth’s magnetic field. This discrepancy, known as magnetic variation, varies across different regions of the world and changes over time. Pilots need to consult aeronautical charts or electronic navigation systems to find the correct magnetic variation for their flight.

Step 2: Account for Wind Drift

Once the magnetic heading is determined, pilots must account for the effect of wind drift. To do this, they need to know the wind speed and direction, which can be obtained from weather reports or on-board weather instruments.

Pilots can then use techniques such as the wind triangle or computerized flight planning tools to calculate the amount of wind drift and the correction angle required. By making these corrections, pilots ensure that their aircraft maintains the desired True Course.

The Importance of True Course in Navigation

True Course plays a critical role in navigation and flight planning, enabling pilots to efficiently navigate from one point to another. By calculating and flying the True Course, pilots minimize the time, fuel consumption, and distance required to reach their destination.

Furthermore, True Course is fundamental for maintaining separation between aircraft, especially in busy airspaces. Air traffic control systems rely on accurate True Course information to coordinate traffic and ensure safe distances between flights.

Moreover, understanding True Course allows pilots to perform effective dead reckoning navigation, where they can estimate their position based on their known True Course, groundspeed, and elapsed time. This skill is particularly valuable in situations where navigational aids may not be available or are unreliable.

Overall, True Course provides a fundamental reference for pilots, helping them navigate the skies with precision and efficiency.

Related Navigation Concepts

Several other navigation concepts are closely related to True Course and are essential for effective flight planning and execution:

Ground Track

The ground track is the actual path an aircraft follows over the ground. It considers the effect of wind and is influenced by the True Course, as well as wind speed and direction. Pilots continuously monitor the ground track during flight to ensure they remain on course.


The heading is the direction in which the nose of the aircraft is pointing at any given time. Unlike True Course, the heading is not adjusted for wind or other factors. Pilots adjust their heading based on the calculated True Course and wind conditions to maintain the desired track.

Track Made Good

The track made good (TMG) refers to the actual path an aircraft has covered over the ground, considering the effect of wind and drift. TMG is equivalent to True Course only when there is no wind present. Pilots compare their TMG with the planned True Course to monitor their progress and make any necessary adjustments.

Understanding these related navigation concepts is crucial for pilots to ensure accurate and safe flight operations.


In conclusion, True Course is a fundamental concept in aviation that represents the actual direction an aircraft must follow to reach its destination, without considering any influences such as wind. By taking into account factors like wind drift, magnetic variation, and groundspeed, pilots can accurately calculate and maintain their True Course throughout their flight. True Course serves as a reference point for navigation, flight planning, and maintaining separation between aircraft. It allows pilots to fly with precision, efficiency, and safety in the ever-expanding skies.

For More: What is OTS in Aviation? (Out Of Service)