Aerospace Exchange Blog

When working with aircraft that feature propeller assemblies, one may notice that each propeller blade features a twisted design. This is an intentional choice during the manufacturing stage, ensuring that blades are able to most optimally perform during flight. To help you better understand this design choice, you will first need to be familiar with the physics of propeller assemblies.

While some may think firewalls are limited to the automobile world, they are actually an integral part of aircraft as well, acting as barriers between an airplane’s engines and the rest of the airframe. Commonly known as bulkheads in the United Kingdom, firewalls are considered a fire-resistant barrier. To better understand their purpose and function, this blog will provide a brief overview of firewalls in aircraft.

While the terms fuselage and airframe are often used interchangeably to refer to the body of an aircraft, they are technically not the same. In fact, the fuselage is a portion of the airframe that includes the middle section of the aircraft but excludes the wings and other extended features. Understanding the technical differences between the two structures is important for anyone operating aircraft, so this blog will delve into the distinguishing features that define each term.

The word “tachometer” is derived from the Greek words “tachos,” which means speed, and “metron,” which means “measure.” However, contrary to what the name may suggest, tachometers do not necessarily track the speed of an aircraft, but rather, they measure an engine’s operating speed in revolutions per minute (RPM). Tachometers indicate the mechanical motion of either the entire aircraft or one of its components. They measure the rotational speed and the angular (aka rotary) velocity of either the disc or the shaft of the rotating body.

Shaft couplings are mechanical elements that join two shafts together and help in accommodating the misalignment of torque from one end to another. These mechanical devices are used for connecting rotating shafts and absorbing misalignments between them. Depending on the alignment precision of the torque and system requirements, couplings can be flexible or rigid.
 
Some of the most common applications of shaft couplings are for torque and power transmission between rotating shafts, like in compressors, generators, and motors. There are many types of couplings that one may procure as well. Let us have a look at the most common types of shaft couplings.

Maintenance crews are often tasked with carrying out a number of standard aircraft safety procedures, two of which include fueling and defueling. These procedures vary from aircraft to aircraft, wherein there may be a prescribed sequence to follow when performing such tasks to prevent damage to the airframe or other structures. As such, making sure that the proper procedures are taking place prior to fueling is paramount.

Have you noticed the nozzle at the back of an aircraft engine and wondered what it does? Like everything in aircraft design, its placement is intentional, and it plays a critical role in helping propel the airplane forward. While nozzles vary from aircraft to aircraft, every jet-engine plane implements a propulsion nozzle in its design. In this blog, we will discuss the function and reasoning behind these important components.

Within the realm of hydraulics, hydraulic fluids allow for power to be efficiently transferred throughout a system for the means of actuating and carrying out processes. Hydraulic fluids can  come in various forms, all of which feature zero compressibility for the means of providing ample power transfer capabilities. With their ability to transfer power, a hydraulic fluid can provide the energy needed to drive various systems including hydraulic brakes, aircraft flight control systems, lifts, excavators, garbage trucks, and much more. To better understand how hydraulic and hydraulic fluids are used for various common operations, we will discuss their types and applications in more detail.

Thermal grease, also known as thermal paste or thermal interface material, is a thermally conductive material used to connect a heat source to a thermal spreading device. Thanks to their diversity and performance, thermal grease can be found in many thermal settings, such as heat sinks. Thermal grease can greatly improve a system’s overall thermal conductivity and effectiveness. In this blog, we will discuss the use of thermal grease, what it does, and its chemical properties.

Flared and flareless fittings are both commonly used throughout the aerospace industry in many applications. For example, the Army-Navy (AN) military standards require tighter tolerances and define all fittings types, wherein the joint intelligence center utilizes AN specifications as a basis to form their own standards covering fewer sizes. This blog will discuss both flared and flareless fittings and their specific types.