pilots cockpit electronic component redundancyCruising at a speed of 336 knots at 39,000 feet is not a time when you want to depend on a single point of failure in critical flight components. Getting up, and staying up, in the air is rather important because breaking down does not mean simply pulling over to the side of the road. Therefore, aircraft normally have built-in redundancy for avionics, communications, and mechanical parts.

Redundancy in Aviation

If flight control avionics begin to fail, most aircraft have an analog console so they can continue to understand the attitude of the plane. There are duplicate systems in the landing gear so it can be deployed manually if the hydraulic system fails. Communications have radio backups. Most aircraft have redundancy in the engine’s system components like an extra battery, alternator, auxiliary fuel pumps, and alternate air intakes. Pilots are taught to plan for alternate landing fields during flights in case of emergency. Even the copilot could be considered part of the redundancy.

Redundancy in Weapons Systems

Redundancy is also incorporated to improve reliability and availability. In aerial combat, it’s a good thing when a missile leaves and hits it mark, when you gain position on the enemy and when you drop ordinance. You want confidence it will perform when you squeeze the trigger. Building in electronic component redundancy ensures that if one part fails, the backup comes through and you can still fire. Weapons buses often have up to four layers of redundancy.

Reliability in a Component or an Entire System

In electronic systems, redundancy might be duplicate components inside of one system that matches each other identically. If the primary component fails, the duplicate begins to operate, keeping everything functioning properly. Or, rather than just a redundant component, an entire duplicate of the electronics system might be the redundancy.

Redundancy for Online Applications

Reliability of uptime and availability of backup data for online applications is important when you are choosing the right hosting company or data center for your business. Redundancy can be in the host’s power capabilities, ability to establish scheduled data backups, duplication of host’s critical electronic components to the reliability, and even the data pipeline.

computer power backup redundancy

A redundant PC power supply for installation in a 19″ case, one of the two bays pulled out halfway. The size corresponds to a standard ATX power supply. (Photo by Smial on de.wikipedia)

Having a backup to electrical power might be an uninterruptible power supply (UPS) at individual work stations or a large battery system encompassing a whole company that activates during power outages. Hosting companies offer options for customers to back up their data at a remote location in case of a failure. For redundancy, a company may choose to have two or more virtual servers, with identical website data, connected by a load balancer. When it comes to delivering data, some hosting companies and data centers often have multiple network routes to ensure delivery.

Is Enough, Enough, or Too Much?

When it comes to redundancy, is enough sometimes too much? It can be when it potentially makes the system too complex and more prone to errors and accidents. With redundancy in place, employees might feel less responsible for the operation of the system, or the pressure for production increases can lead to higher speeds and less safety. Redundancy also commonly increases the cost of system design. With the high cost of failure leading to loss of production, damaged or lost equipment and materials, and even injuries or death, the high cost of redundancy is likely still appealing.

Quadruple Redundancy


Open circuit boards space is one of four demonstrating the quadruple redundancy of the Analog Flight Control Computer

A great example of electronics redundancy would be the Flight Control Computer (FCC) and Digital Flight Control Computer (DFLCC) of the F-16 Fighting Falcon. These line replaceable units (LRUs) of the fighter jet’s fly-by-wire flight controls are quad-redundant to avoid costly failures like loss of pilots and aircraft. The FLCC (F-16 A/B), or the updated DFLCC (F-16 C/D), provides pitch, roll, and yaw command signals to the flight control system. Instead of mechanical flight systems like 3rd generation aircraft and earlier, the flight control computers of the F-16 take information from flight controls of the rudder and stick which are converted to electrical signals and transferred by wire to the Flight Control Computer. The FCC then determines how to affect the flight control surfaces to provide the expected response. Unlike mechanical or hydraulic flight control systems, which can fail gradually, the electronically oriented fly-by-wire system could suddenly cease to operate – not a good situation to experience for a pilot flying at the edge of an aircraft’s performance envelope. To ensure operational reliability, the aircraft’s engineers opted for quadruple redundancy throughout the Falcon’s flight control system.

Redundancy Is Not Essential

Redundancy is not essential in your car. If your alternator stops functioning you can bring it to a shop. If the electronics die and your truck stops running, you just coast it to the side of the road. Redundancy in your home’s electronics is not essential. If the DVR stops working, you call the service provider for a replacement. If the power goes off in your house, it’s likely to not be critical.

Redundancy For Success

However, if you have a website that needs to remain up nearly 100% of the time, you host at a source with redundant capabilities. If your company’s success depends on data you collect and your employees’ ability to work on their computers, then you establish redundant measures to perform regular backups and redundant power sources for work stations. If electronics must function to keep a plane safe in the air, or if electronic devices need to remain up for mission-critical success, then redundancy and the costs and complexity associated with it are worth every cent invested. Duotech is a leading source for repairing the Flight Control Computer (FLCC) and the Digital Flight Control Computer (DFLCC). We provide Depot Repair Services for a wide variety of electronic and electromechanical systems for military and commercial applications. When it is essential that your electronic components and systems are functioning properly, depend on Duotech Services to keep them properly functioning for your mission success.

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