FAA Ground School Practice Test

In which airspace is an operational 4096-code transponder with an encoding altimeter required?

1. Class C and Class D airspace

2. Class A, Class B, and Class C airspace

3. Only Class B airspace

4. Class D airspace only

The correct answer is: Class A, Class B, and Class C airspace

An operational 4096-code transponder with an encoding altimeter is required in Class A, Class B, and Class C airspace to ensure safe and efficient air traffic management. Class A airspace, which extends from 18,000 feet mean sea level (MSL) up to and including flight level 600, requires all aircraft to have a functioning transponder to participate in the controlled environment where air traffic is heavily monitored. Class B airspace is typically found around major airports where there is a high density of aircraft operations. Here, the transponder improves situational awareness for both pilots and air traffic controllers by providing precise location and altitude information. Class C airspace, which surrounds airports with a significant amount of traffic but not as dense as Class B, also mandates the use of a transponder to maintain safety and enhance communication between pilots and air traffic control. While Class D airspace, which usually extends up to 2,500 feet above the airport elevation, does require a transponder if the aircraft is above a certain altitude (but not always), it does not necessitate the same strict transponder requirements as the other classes. The necessity of the advanced transponder system primarily comes into play in Class A, B,