A-034-4-16

A-034-4-16 in the A-034-4 indicator family

The A-034-4-16 belongs to the unified A-034-4 family of radio altimeter indicators. Indicators in this series are structurally similar and differ mainly by display range, scale graduation, markings and system compatibility. The A-034-4-16 version is intended for indication from 0 to 750 meters. This makes it suitable for low- and mid-altitude flight regimes where the crew needs direct reading of actual clearance above the surface below the aircraft.

Scale range and graduation of A-034-4-16

The A-034-4-16 scale is divided into three measurement zones. From 0 to 20 meters, the scale has 2-meter divisions for more precise reading close to the ground. From 20 to 100 meters, the divisions are 5 meters. From 100 to 750 meters, the scale uses 50-meter divisions for simplified reading at higher radio altitudes. This layout gives better visual precision near the ground while keeping the upper part of the scale readable in flight.

Danger altitude warning on A-034-4-16

The indicator includes a danger altitude adjustment sector with a rotary selector. The selected threshold is used by the radio altimeter system for low-altitude warning. When the aircraft descends below the preset height, the integrated yellow warning lamp provides visual warning to the crew. This function is important during descent, approach, landing, hover and low-level flight, where quick awareness of the selected minimum height is required.

Fault indication and TEST function

The A-034-4-16 includes a drop-out blinker flag for fault indication. The flag appears when the radio altimeter becomes inoperative, loses usable ground reflection or cannot provide valid altitude information. The front-panel TEST push-button allows cockpit verification of the system. In a serviceable installation, pressing TEST moves the pointer to the reference value according to the radio altimeter documentation. If the system does not respond correctly, the blinker flag is shown.

Installation and compatibility

The A-034-4-16 is installed on the aircraft cockpit instrument panel and operates together with A-037 series transceivers and antennas. Compatible transceiver versions may include A-037-1A, A-037-1B, A-037-1V and A-037-1G, depending on the installed radio altimeter configuration. The indicator receives power through the A-037 system electronics. Compatibility should always be checked by aircraft documentation, indicator range, transceiver version, wiring and required warning functions.

Identification and supply of A-034-4-16

For procurement, the full designation A-034-4-16 should be used. Alternative references such as A034-4-16, 750 m indicator or A-037 pointer indicator can help identify the item, but the exact designation remains the main reference. Before supply or installation, it is important to confirm the display range, scale graduation, condition, warning lamp, blinker operation, TEST function, connector compatibility and documentation.

Related instruments: A-034-4-12, A-034-4-24, A-034-4-17. These links are grouped by function and system context and do not indicate interchangeability.