Radar Altimetry

The CARA is an advanced technology, all solid-state radar altimeter. It provides analog and digital outputs for use by aircraft avionics systems


The CARA Receiver-transmitter (RT) transmits a signal to the earth’s surface, receives the reflected signal, processes the information, and provides the resulting altitude-related data from 0 to 50,000 feet to various avionics systems. The system is designed to meet the stringent environments of present and future applications and is compatible with both high and low altitude high-performance aircraft.


Interfaces contained in the RT are sufficient to interface with many basic applications, however, in order to accommodate the multitude of electrical interfaces contained in various aircraft types, Signal Data Converters (SDCs) are used to interface the RT to many avionic systems. Over a dozen SDCs are available with popular interfaces, including:


Over a dozen SDCs are available with popular interfaces, including:
• Mil-Std-1553B
• ARINC 429
• ARINC 552
• RS-232
• RS-422
• Various analog, discrete and special interfaces


Navcom CARA

Because CARA is the United States Air Force’s standard altimeter, it is compatible with many retrofit and forward-fit installations, and offers performance capability and versatile functions not found in other radar altimeters. Low life cycle cost, which was a primary goal for the CARA design, is inherently obtained from the high system reliability, unique multi-SRU modular construction and automatic self-test with fault isolation to the line replaceable units (LRUs).


The CARA system can be easily interfaced with most modern Ground Proximity Warning Systems (GPWS), Terrain Avoidance and Warning Systems (TAWS), Terminal Collision Avoidance Systems (TCAS) and other CNS/ATM solutions directly from the common Receiver Transmitter or through additional interfaces available with the numerous SDC configurations.


Maintenance is supported both at USAF and NavCom depots. Organizational and Intermediate test capabilities are available.


Over 11,000 CARA systems have been delivered. The radar altimeters replaced and the aircraft installations are:


RadarAltimeters Replaced with NavCom CARA