Picture of product RA-4000

Part #:

Model: RA-4000




Radar Altimeter System

Part Number :

  • Radar Altimeter System (TSO-Certified)
  • RA-4000 consists of a remote unit and dual antennas
  • Shipset includes RA-4000 system & RAD-40 control
  • Version available with FTG-410 Tone Generator
    • Gives pilots important audio alerts when operating at low altitude, at night, over water or rough terrain when there are few visual cues to the surface, landscape or flight path
  • Provides dependable, accurate above-ground-level (AGL) information
  • Valuable for flying search and rescue missions, forestry operations, pipeline maintenance, off shore helicopter ops, helicopter emergency medical services (HEMS), other aero-medical emergency services, border patrol, and electronic news gathering operations
  • Suited for a broad range of fixed & rotary wing aircraft
  • Designed for applications such as helicopter and seaplane operations where accuracy is needed down to zero feet
  • Provides precise AGL information from 2500 feet down to ground level
  • Lightweight, easy to install with flexible aircraft placement
  • Compatible with FreeFlight Systems RAD-40 Radar Altimeter Display
  • Optional NVG compatible display
  • Meets Precision Equipment output specification of TSO-C87 & ETSO-2C87
  • Increased pilot safety
  • Software zero calibration

NOTE: the key difference between RA-4500 & RA-4000 Radar Altimeters: the RA-4500 has ARINC 429/optional ARINC 552 output (EFIS Interface)

  • Panel-mount Radar Altimeter Display
  • Compatible with the FreeFlight Systems RA-4000 & RA-4500 Radar Altimeters
  • Provides critical AGL information
  • Bright LED
  • RS-422 Serial Interface
  • Rotary knob on front panel
  • Knob sets decision height (DH)
  • When the preset altitude is reached, a DH LED is illuminated and a DH discrete output is set
  • 5 trip-point discrete outputs (100-1000 ft) to signal additional alerts
  • Optional night vision goggle (NVG) compatible display
  • Round faceplate adapter for display
  • -0200 version fixes false trigger issue & updated software raised to DO-178B, Level C
Altitude Range: -20 to 2500 ft Power Requirements: 20 - 36 VDC; 400 mA MAX @ 28 VDC
Environmental: -67°F to +158°F; Alt: 50,000 ft Dimensions: 3.06"H x 3.15"W x 6.78"L
Weight: Unit: 1.9 lbs Ant (2): 0.37 lbs Transmitter Power:  100 mW minimum out of transmitter
Frequency: Frequency modulated continuous wave 4.3 GHz center frequency sweep, 4.25 to 4.35 GHz Update Rate: 25 times/sec 
Altitude Accuracy: 0 to 100 ft ± 3 ft 100 to 500 ft ± 3% 500 to 2500 ft ± 5% Display Disable: Strut switch inputs
Self Test: Power-on self test & recurring built-in test Inputs: Strut Switch 
Outputs: RS-485/422, RS-232C FAA: TSO-C87 Precision Equipment
EASA: ETSO-2C87 Environmental: DO-160E
Software: DO-178B, Level C    
Altitude Range: -99 to 9999 ft (will show -20 to +2500 ft when used w/RA-4000) Power Requirements: 9 - 36 VDC; 450 mA @ 28 VDC
Environmental: -4°F to +131°F; Alt: 50,000 ft Dimensions: 1.39"H x 3.54"W x 4.62"L
Weight (2): 0.38 lbs Type:  LED, yellow seven segment
Update Rate: 2 times/sec Decision Height Selection: 10-ft increments to 200 ft, 50-ft increments from 200 to 950 ft
Flags: Displays Dashes when altimeter is unlocked ("----") Self-Test: Lights all "8's" for LEDs and activates the DH LED
DH Alert: Internal DH LED and external discrete output Trip Point Outputs: Five fixed trip points: 100, 150, 200, 500 & 1000 ft
Environmental: DO-160F Software: DO-178B, Level D (-0200 software version: DO-178B, Level C)
Part Number Radar Altimeter Description:
84560-01-200B Basic RA-4000 Unit (R/T Unit Only. Does not include other items shown) Item discontinued - superseded by 84560-11-300A
84560-11-300A RA-4000 Unit with latest software version. (R/T Unit Only. Does not include other items shown)
84939-00-0100 Basic RAD-40 (Unit Only) - REPLACED by -0200
84939-00-0200 Basic RAD-40; Replaces PN 84939-00-0100; DO-178B, Level C
84939-10-0100 Basic RAD-40 NVG (Unit Only) - REPLACED by -0200
84939-10-0200 Basic RAD-40 NVG; Replaces PN 84939-10-0100; DO-178B, Level C
RA4000/RAD40 Shipset Complete System (Basic RAD-40 Version)
RA4000/RAD40 NVG Shipset    Complete System (RAD-40 with NVG)
RA4000/RAD40 w/TG Complete System (with FTG-410)


- Radar Altimeter Transceiver
Price Condition Status
- Radar Altimeter System
Price Condition Status
RA4000/RAD40 NVG
- Radar Altimeter System (NVG)
Price Condition Status

Click on a question below to see the answer. If you have a question about this model that is not answered below, please contact questions@seaerospace.com

In relation to NE (New) parts, many OEMs change their prices and availability without any notice to dealers or the industry. Therefore, through the REQUEST or RFQ indication, we ask that customers contact us for the most accurate price and availability.

In relation to SV & OH parts, the used parts aftermarket in the aviation industry is not an infinite supply. It is a dynamic, constantly changing market that is significantly affected by and susceptible to highs and lows in supply and demand. Therefore, although we attempt to, at times, we are unable to predict the exact moment when an item may be available. Once again, through the REQUEST or RFQ indication on our website, we ask that customers contact us for the most current and accurate price and availability.

No, the RA-4000 is designed to be used with the RAD40 indicator or interfaced to modern flight displays RS-232/422/485 and ARINC 429 interfaces.
Yes. Free Flight uses part number 9-1203-115-00 in their catalog and installation manual for the radar altimeter antenna used in their RA3500, RA4000, and RA4500 systems. When you inspect these antennas, they are packaged in a Sensor Systems box with the 9-1203-115-00 part number label on the outside of the box. When you open the Sensor Systems box, you can immediately see that it is actually the Sensor Systems S67-2002 antenna. The antenna has the S67-2002 part number on its dataplate.

When replacing the TRA3500 with a RA4500, the only parts that can be reused are the antennas. The change will require different length cables, replacement of interconnect wiring form the RA4500 to an indicator and the indicator needs to be replaced with the RAD40 or other PFD with ARINC 429 input. The original TRI40/TRA3500 system only uses a single coax to interface them together, while the RAD40/RA4500 system will need power, ground and a twisted shielded pair for the data line.

You will also need to consider if the current TRI40 has any audio interface. The RAD40 does not have an external audio connection. If your installation requires an external DH audio output, then an additional tone generator will be needed.

However, if you are only replacing the TRA3500 system and will not be interfacing it to any other equipment, the RA4000 system will perform the same function at a less cost than the RA4500.