The benefits that MIL STD 1553 provides to the military avionics

The benefits that MIL STD 1553 provides to the military avionics

Multi-Channel Coordination and Selection

In regards to modern military aircraft, it is critical that avionics systems are able to communicate discretely with one another. This was challenging in the past, specifically when regarding the more traditional ARINC-429 architecture. However, the MIL STD 1553 standard makes use of a bus controller.

Otherwise known as the “BC,” this controller is effectively a means to segregate specific commands intended to reach recipient systems. Therefore, these commands will be carried out in order of priority. Obviously, this is important when referring to hardware packages such as those found within fifth-generation fighters including the F-22
Raptor and the F/A-18E Super Hornet. Without such coordination, valuable time would be lost when specific responses to threats are required.

Real-Time Redundancy and Efficiency

Some past avionics systems were associated with a single input-output configuration. In simpler terms, all data was transmitted through a single wire. If this wire became damaged or severed, catastrophic failures such as a loss of yaw capabilities or a weapons system malfunction would likely occur. This is the primary benefit of the dual redundancy associated with the MIL-1553 framework. A redundant backup bus controller will immediately activate if the primary system is compromised.

Secondly, data burst and transmission rates are dramatically increased as compared to the aforementioned ARINC-149 system. As opposed to 100 KHz, MIL-1553 employs speeds of 1 MHz. This enhances transmission speeds and in a real-world scenario, the operator will have a more flexible window in regards to response times.

Maintenance and Reliability

Thanks to designing simplifications, the MIL-1553 standard is now associated with fewer connections. Not only will this enable the systems to be much lighter (an obvious concern with any aircraft), but fewer connections directly equate to fewer chances of failure and greater MTBF (Mean Time Between Failure) cycles. Fewer parts are also associated with easier installation as well as the ability to upgrade such systems on a modular basis when required. This is an obvious logistical concern when referring to FOB (Forward Operating Base) requirements.

The Exclusion of Remote Terminal Issues

Many previous systems employed a rather egalitarian approach in reference to avionics communications. This could present a very real problem if multiple RTs (Remote Terminals) send conflicting messages. Thanks to the top-down approach associated with the MIL-1553 standard, this is no longer a concern. All messages are preceded by a command word and are initiated ONLY by the bus controller. This eliminates simultaneous transmissions.

The Future Role of MIL-STD-1553

It only makes sense that this architecture will continue to evolve as the concept of sixth-generation fighter aircraft becomes a reality into 2020 and beyond. However, it is clear that this advanced generation of avionics will certainly benefit from the principles espoused by the MIL-STD-1553 protocol.