What is the purpose of MRA (Minimum Reception Altitude)?

The purpose of Minimum Reception Altitude (MRA) is indeed related to the ability to receive navigational signals from two different navaids, thereby providing redundancy for navigation. When flying at or above the MRA, pilots can ensure that they are in a position to receive reliable signals from multiple sources, which is especially important when one navaid might be out of range or experiencing issues. This helps maintain situational awareness and navigational accuracy during flight.

Regarding the other options, the lowest altitude for landing safely pertains to different criteria, typically involving decision heights or minimums defined for approaches. Aligning the aircraft for landing is a function of final approach techniques and procedures, not directly linked to MRA. Communication with ground control mainly involves operational altitudes and radio communication protocols, rather than reception altitudes linked to navigational aid signals. Understanding the role of MRA helps pilots ensure that they can maintain navigational integrity while flying in complex environments.