What is a Machmeter?

While there is a universal understanding that aircraft move at incredible speeds, surpassing an aircraft's imposed speed recommendations can produce hazardous consequences. To provide pilots with visual awareness of current airspeeds being traveled at, devices like airspeed indicators (ASI) are typically used. Depending on aircraft model, various measurement conventions can be used to calculate airspeed and range from indicated airspeed (IAS), calibrated airspeed (CAS), equivalent airspeed (EAS), and true airspeed (TAS). However, to distinguish airspeed on high-speed aircraft such as jets and airliners, a machmeter must be employed. Indicating airspeed as a Mach number (M), machmeter instruments project the ratio between an aircraft’s true airspeed (TAS) and the speed of sound (LSS) when measured by a pitot-static system.

Representing a quantity of fluid dynamics, Mach numbers are designed to indicate how fast an aircraft is traveling relative to the speed of sound. When an object exceeds the speed of sound, airspeed measurements are converted to M on a scale of 0-10 to account for subsonic, transonic, supersonic, hypersonic, and high-hypersonic speeds. Often portrayed as a simple needle and dial instrument, machmeters generally incorporate limiting numbers to specify an aircraft's maximum Mach speed, and they can be combined with ASI for further benefits on provided readings. Affixed with a pressure-sensitive assembly known as a pitot-static system, these components consist of a pitot tube, static port, and multiple pitot-static instruments. Beside being essential for determining an aircraft's Mach speed, pitot-static systems also serve to aid in a myriad of functions including: airspeed switching, air data computers, flight data recorders, altitude controllers, and cabin pressurization controllers.

Wholly dependent on atmospheric conditions, Mach speeds are inconsistent and do not indicate a set airspeed. However, exceeding the speed of sound can be achievable at roughly 768 mph or 1,235 km/h. Though, this is only relevant when the temperature is 68°F and atmospheric conditions are normal to dry. Otherwise, as the speed of sound is inconsistent and changes depending on regional weather conditions, Mach numbers are simultaneously impacted. As such, although two aircraft can travel faster than the speed of sound at the same Mach number, because local weather phenomena can vary at each pilot's present location, each aircraft may be moving at completely different speeds.

Despite the fact that not all high-speed aircraft go beyond subsonic speeds to achieve transonic or supersonic flight, it is still imperative that pilots utilize an aircraft's critical Mach numbers to maintain safe flight during changes in elevation, turns, and more. If an aircraft's critical Mach number were to be purposefully exceeded, this could result in a loss of control over the vehicle, leading to increased drag, wing stalling that results in unusable control surfaces, and crashes.

To ensure your flight is always a safe one, regular maintenance should be performed to mitigate part failure before it happens. For the acquisition of top-quality items, we invite you to browse our inventory for numerous machmeter instruments ready to be put to use. Whether you require a gasket machmeter, simulated machmeter, pitot and static assemblies, and more, ASAP 3Sixty is here to streamline and expedite any one of your orders for immediate procurement. Due to our quality control and export compliance, we operate with AS9120B, ISO 9001:2015, and FAA AC 00-56B certification and accreditation, alongside our NO CHINA sourcing pledge. If you would like to request a quote for your comparisons, you can submit an RFQ form as provided on our website. Upon receipt, a dedicated account manager will quickly review and respond with a personalized solution to your needs in just 15 minutes or less, 24/7x365.  

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1. craig lewis
2. Posted on October 19, 2021
aviation

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