The Most Important Electrical Components for Ground and Air-Based Systems

Modern aircraft rely extensively on electrical infrastructure to carry out everything from managing cockpit communications to controlling fuel flow and regulating cabin conditions. More than just wires, a wide variety of electronic components work in tandem to uphold performance both in the air and on the ground. In this blog, we will explore several vital electrical components that help keep both aircraft and ground operations running smoothly, examining their core functions and the roles they play within broader aviation systems.

Power Generation, Distribution, and Control Components

Alternators

Alternators are the primary source of electrical power in most modern aircraft, converting mechanical energy into alternating current (AC). This AC power can also be rectified into direct current (DC) to meet specific system requirements. Relying on rotating magnetic fields and stationary armature windings, alternators are more efficient, compact, and less prone to wear compared to older generator designs that contain brushes and commutators.

Batteries

Batteries provide DC power when engines are off or when backup power is needed. In flight, they support operations such as engine starts, initializing avionics, and providing emergency power. Meanwhile, battery banks also power ground support equipment and UPS systems at airfields to maintain lighting, communications, and navigation systems during outages or transitions. Common battery types include:

• Lead-Acid Batteries: Lead-acid batteries are reliable, cost-effective, and widely used, but they are heavy and susceptible to reduced lifespan if mismanaged.
• Nickel-Cadmium (Ni-Cd) Batteries: Suited for larger aircraft, these batteries offer high discharge rates and temperature tolerance, although they need monitoring to avoid overheating and voltage memory effects.
• Lithium-Ion Batteries: Known for their energy density and low weight, lithium-ion batteries are popular in modern aircraft and UAVs. However, they require advanced battery management systems (BMS) to mitigate the risks of thermal runaway and overcharging.

Power Distribution Units (PDUs)

Power Distribution Units (PDUs) manage the flow of electrical current to various subsystems, integrating circuit breakers, relays, and wiring interfaces in a single unit. As such, they provide organized routing, overload protection, and quick isolation of circuits for maintenance or fault resolution.

Circuit Control and Protection Devices

Circuit Breakers

Circuit breakers are automatic safety devices that interrupt the flow of electricity when current levels exceed safe limits, effectively protecting wiring and equipment from overheating or failure. Key variants include:

• Thermal Circuit Breakers: These devices operate using bimetallic strips that deform under excessive heat, causing the breaker to trip. They are manually resettable and valued for their simplicity, though their performance may vary with ambient temperature.
• Magnetic Circuit Breakers: Activated by electromagnetic force, these breakers provide faster and more consistent tripping action regardless of surrounding conditions.

Relays

Relays are electromechanical or solid-state switches that enable low-voltage control circuits to safely operate high-voltage or high-current loads. They are essential for isolating control logic from power distribution systems, serving engine control systems, environmental systems, electrical load management, and flight deck panel functions. On the ground, relays fulfill similar roles in automating equipment, managing electrical loads in support vehicles, and facilitating remote control of power systems in maintenance and testing stations.

Wiring and Interconnection Components

Cables and Wiring Harnesses

Aircraft demand an intricate, wide-spanning network of wiring systems, which must be precisely routed within tight spaces while remaining resilient against vibration, moisture, temperature extremes, and electromagnetic interference (EMI). For this reason, wiring harnesses are incorporated to simplify installation and create consistent routing through an airframe, grouping multiple conductors into organized, space-efficient bundles.

Several cable types are used to meet distinct operational needs, including:

• Coaxial Cables: Designed for radio frequency (RF) signal transmission, coaxial cables are used extensively in communication, radar, and navigation systems due to their excellent shielding properties.
• Shielded Cables: These cables feature conductive shielding layers that minimize EMI, helping to protect sensitive systems.
• High-Temperature Wiring: Required in engine bays and other high-heat zones, these wires use insulation materials such as Teflon or Kapton to prevent thermal degradation.

Connectors

Electrical connectors aid in linking subsystems together, enabling modularity, serviceability, and fault isolation. They come in a vast array of shapes and sizes, but the most standard connector types present in aviation include:

• Circular Connectors: Rugged and easy to mate, circular connectors are favored for military and commercial applications that require vibration resistance and environmental sealing.
• Rectangular Connectors: These connectors serve applications that benefit from high pin density and installation within narrow enclosures, such as flight control computers and mission systems.
• Fiber Optic Connectors: With increasing demand for high-speed, EMI-resistant data transmission, fiber optic connectors are becoming more prevalent in advanced avionics and in-flight entertainment systems.

Sensors and Transducers

Sensors and transducers create a bridge between physical conditions and electronic control, converting variables like pressure, temperature, and movement into measurable electrical signals that can then be processed by flight computers or control modules. Some of the types used in aircraft include:

• Thermocouples and Resistance Temperature Detectors (RTDs): These devices measure temperature with high accuracy, used extensively in engine monitoring, exhaust gas analysis, and environmental control systems.
• Current Sensors: Installed in power distribution systems, current sensors monitor electrical load conditions to prevent imbalances across generators or buses and report anomalies or overloads.
• Position Transducers: These devices track the physical position of flight control surfaces, ensuring correct actuator response and allowing for closed-loop control in fly-by-wire systems.

Source Quality Electrical Components through ASAP Aerospace

As illustrated, ground and air-based systems rely on a complex ecosystem of electrical components. From foundational parts like alternators to intricate sensors, selecting the right components is a crucial aspect of safety and long-term performance. As such, having unrestricted access to a dependable range of industry-compliant products is critical.

ASAP Aerospace, an ASAP Semiconductor owned platform, offers a streamlined solution for purchasing thousands of top-quality electrical components and other aviation-grade parts. With a focus on certified products and maintaining relationships with trusted manufacturers, you can put your trust in any item you come across here. In addition, we strive to provide competitive pricing, swift fulfillment, and tailored procurement solutions for every order. Taking this into account, get in touch with a team member today to see how ASAP Aerospace can serve you!