Model: KRA-405

BendixKing - Radio Altimeter R/T
Part Number :

  • 2000 ft. display
  • Internal 2500 ft. capability for use with ground proximity systems
  • Used with KNI-415 and KNI-416 indicators
  • Used with two KA-54 or KA-54A antennas
  • Has capability of alerting pilot when a predetermined altitude (decision height) is reached
  • Provides altitude information to the flight control system during approach
  • Versions available with 2 or 3 altitude trips (see table below)
  • 28VDC
  • TSO'd
Size: 3.00"W x 5.00"H x 11.00"L Receiver Weight: 6.3 lbs.
TSO Compliance: C87; DO-138 Env. Cat. DO-160A; AG/A/NJ/AAAEXXXXX; Altitude CAT F2 Temperature Range: -54C to +71C
Part Number Radar Altimeter Description
066-1048-00 Original version with 2 altitude trips
066-1048-02 Current production version, product improvement of -00 with 3 altitude trips


- Radio Altimeter R/T
Price Condition Delivery

SEA Repair Capabilities: Yes

- Radio Altimeter R/T
Price Condition Delivery

SEA Repair Capabilities: Yes

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

There is no difference in the specifications of the KRA-405 P/N 066-1048-00 and -02 versions other than that the -00 has two altitude trips and the the -02 has three altitude trips.

Also, the -00 provides 2 altitude trip points at 200 and 500 feet. The -02 provides 3 altitude trip points at 200, 500, and 1200 feet. These altitude trip points are factory settings.
None, they represent the same unit. Original King Radio part numbers were 9 digits. For example, 066-3056-01. During the Bendix and King merger (i.e. Bendix/King), a new part numbering system was created that converted these 9 digit part numbers to 12 digits. Therefore, 066-3056-01 became 066-03056-0001. Despite this numbering change, units that were originally from the King Radio design still have the 9 digit part number format on the unit dataplate. The 12 digit format for King units appears to be used for catalog and internal Honeywell purposes only. Therefore, any unit that has a zero in its third to last number (i.e. XXX-XXXX-X0XX) has a 9 digit part number (i.e. XXX-XXXX-XXX) on its dataplate / ID Plate.

Yes, please see SEA Promotion.

In January 1989 Bendix/King changed from a nine digit to a twelve digit part numbering system. The new, larger 12 digit numbers allowed for the inclusion of software version into the last two digits of the part number for certain units in which software changed frequently such as EFIS and TCAS processors. Therefore, the two digits immediately preceding the software version indicate the hardware version of the unit.

Different software versions imply different operational features and/or interface capabilities and software modifications imply software repairs (bug fixes) to insure proper operation of these features and interfaces. Software version upgrades frequently require hardware modifications to the unit. Such hardware modifications accompanying software version upgrades do not necessarily change the hardware version of the unit.
+/- 5 ft (1.5m) or +/- 5% (whichever is greater) at 0-500 ft and +/- 7% at 500-2000 ft
Dirty antennas can sometimes cause poor or erratic operation of the radio altimeter system. Especially during winter months, some aircraft's nose wheel's throw dirt and slush onto the antenna. As a preventative measure to keep the antennas clean, a quality aircraft wax can be applied to the antenna.
Display lockup is a commonly encountered problem where the indicator locks up at a low indicated altitude between 5-50 feet. Some pilots will report that the radio altimeter will work normally at low altitudes but after climbing above a certain altitude the indicator locks up. Once the aircraft descends past the locked altitude, the radio altimeter works normally again.

In almost all cases, the cause of lockup is excessive signal leakage between the receive and transmit antennas. Signal leakage is commonly caused by the following situations:

- Antenna reflections hitting an object below the fuselage such as landing gear, skids, or searchlights.
- Poor ground plane between the antennas and the airframe, antennas not mounted on the same piece of metal, or antennas mounted on composite material
Sometimes a pilot may report that the radio altimeter may start indicating altitudes in the rad alt range (0-2500 ft.) at altitudes between 18000-20000 feet. This frequently occurs when flying over a reflective surface such as calm water. What occurs with second time around acquisition is that the receiver detects a return signal that was transmitted two pulses earlier not the transmitted signal it should be receiving. The time between transmitted pulses is equal to a distance in the 18000-20000 ft. range. Therefore, the receiver may process it as though it was signal it was actually trying to receive and then display the incorrect altitude.
Large needle fluctuations is a problem commonly seen when a helicopter is hovering over a soft, diffused surface such as grass. Needle jumps are usually less than 50 feet but can range from hundreds to a thousand feet. Once the helicopter moves forward, the radio altimeter should operate normally again. This needle jumping occurs because the radio altimeter is experiencing decreases in received signal strength. Over a soft, diffused surface, the signal reflection consists of hundreds of small weak reflections with different time and phase, directional qualities. These differences cause cancellations in the total return signal and cause the needle to jump.

To correct this needle jumping, some radio altimeters have an extended dB STC range. This extended range provides an additional receiver gain that can reduce the decreases in signal strength. However, the additional dB gain increase can subsequently increase the potential for display lockup caused by poor isolation between the antennas.
In civilian aviation, these two terms are used interchangeably and essentially mean the same. They both can be abbreviated as "Rad Alt" sometimes as well.

This system measures the between an aircraft and the ground directly below it. "Radar" or Radio Detection and Ranging is the principle by which the system operates. That is, a signal is transmitted towards the ground and then received back for processing. The time the signal takes to reflect back to the aircraft is timed and this is how the altitude is measured. The signal that is transmitted is a radiowave. Thus, this is perhaps this is the reason why some may use the term "Radio Altimeter" instead of "Radar Altimeter".
Southeast Aerospace exchanges are based on the return of an undamaged, economically repairable core unit with identical part number as the unit shipped to the customer. An "economically repairable" core is defined as one where the cost to repair/overhaul (or Repair Cap) does not exceed 80% of the original SV/OH exchange price billed. Should the Repair Cap exceed 80%, the customer will be billed the additional amount. In the event this amount exceeds the Outright Price for the unit, the customer would only be billed the difference between the Outright Price and SV/OH Exchange Price with the core returned as-is to the customer.

Here is an example of such a transaction:

$1000 Exchange Price charged to customer
$1000 x .8 = $800 Maximum Allowable core repair charge or Repair Cap

$2000 Cost to repair core unit
- $800 Less Core repair cap
$1200 Additional billing amount.

2200.00 Total Cost of transaction

Please Note:
SEA offers exchange on new items as well. However, repair cap as indicated above is still based on SV/OH exchange price.

Negotiating the exchange price of a unit only limits the allowable repair cap for the core unit. Southeast Aerospace's exchange transactions are based on the return of economically repairable core unit. Once the core is received and evaluated, the core repair cost incurred by SEA cannot exceed 80% of the original exchange price. That is, it cannot cost SEA more than 80% of the original OH/SV exchange price collected from the customer. Therefore, when and if an SEA exchange price is discounted, there is a risk that additional charges may be assessed once the core is returned and evaluated.

For more information, please refer to these other Exchange FAQs

Most of the King (now Honeywell) Gold Crown components were originally manufactured in the early to mid 1970s. King then Bendix/King now Honeywell discontinued production these components many years ago replacing them with the Bendix/King Gold Crown III product line.

Most of the original Gold Crown products incorporate 1960s and 70s analog technology. As a result, most service parts needed to maintain and repair original King Gold Crown components are no longer available. Therefore, you will experience limited to no warranty available and unreliability for all of the original Gold Crown units.

Southeast Aerospace offers many affordable, upgradeable options for aircraft with original Gold Crown avionics. As avionics integration specialists and premier Honeywell Bendix/King dealer, Southeast Aerospace is experienced and knowledgeable on all Gold Crown generations.

If you are interested in upgrading any of your original Collins Gold Crown systems, then please contact us for the most reasonable, optimal choice available.
The "stripline" in all avionics equipment is an assembly that operates in the microwave frequency range (usually.3 GHZ to 30 GHZ) in the RF assembly of the unit. It contains all stages that operate in that range, such as Local Oscillators, RF amplifiers, heterodyne mixers, transmission lines (called waveguides).

Avionics components such as DMEs, transponders, radio altimeters, and weather radars commonly include stripline assemblies.