Picture of product TRI-40

Part #:

Model: TRI-40




Radar Altimeter Indicator

Part Number :

  • Compact, LED display radio altimeter indicator
  • Used in conjunction with TRA-3000 and TRA-3500Transceivers
  • 28 Volt power input
  • Displays AGL and preselected decision height (DH)
  • Provides audible warning when descent is below DH
  • Test button send a 40-foot altitude code to indicator to test the display and warning alerts
  • External DH output
  • Includes visual and audible gear-up warning when aircraft is below 100 feet
  • Version available with Night Vision Goggle (NVG) capability (see table below
  • Trip-point output allows activation of additional pilot alerts
  • Trip Points for -X0 Versions: every 100 feet up to 800 feet
  • Trip Points for -X1 Versions: 100, 150, 200, 300, 400, 500, 700 & 1000 feet
Dimensions: 1.375"H x 3.5"H x 7.5"L Weight: 0.75
DH selection: Dependent on P/N version, see features above Flag: Displays "U" when unlocked
Self-Test: Indicates "8's" then DH & gear lights, then 40 ft. altitude Aural DH: 1-khz tone output
Part NumberRadar Altimeter Indicator Description:
1901-3040-00 Basic version
1901-3040-01  Basic version w/Alt Trip Points, See Features Above
1901-3040-10 NVG version
1901-3040-11  NVG version w/Alt Trip Points, See Features Above


- Radar Altimeter Ind (w/ Alt Trip Points)
Price Condition Status
- Radar Altimeter Indicator (NVG)
Price Condition Status
- Rad Alt Ind - NVG (w/ Alt Trip Points)
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.

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.