Weighing general aviation (GA) aircraft, helicopters, turboprops, corporate jets, or transport category airliners can be accomplished in two ways: top of jack load cells and platform scales. Equipment selection is dependent on the operator’s needs and or equipment currently on hand, as well as the airframe manufacturer’s recommendations. Using load cells, whereby the aircraft is lifted up, or using a weighing platform. For this weighing, the aircraft is pulled by a tow truck onto yellow platforms. Each wheel has itsown set of scales. “They can calculate the total weight by combining the weights measured at all the platforms. It’s really important that the aircraft is standing exactly horizontally at this point. To ensure this, they use a plumb line, which is a thread with a piece of lead on the end.”
weighing process .!
Every four years each aircraft’s diary says it’s time for a weighing session.
An appointment is made with Weight & Balance in the hangar.
The aircraft is completely emptied. The kerosene is drained out of the aircraft, right down to the last drop. Then the drinking water and toilet water are removed.
The Ground Engineers prepare the aircraft for weighing and make sure it really is empty and dry (rainwater can distort the measurement by adding extra weight).
The Weight & Balance engineer uses a checklist to ensure the contents of the plane have been removed entirely.
The aircraft is weighed.
File the weight.
Scales are like torque wrenches and you would not use a 100 foot-pound torque wrench to torque a 20 inch-pound nut. Why then would you use a 150,000-pound scale system to weigh a light GA aircraft, turboprop, or helicopter? We see this practice a lot where many shops and or technicians use large scale systems to weigh light aircraft, or they have the wrong size cell top to fit a large jet jack point.
There are many military surplus scale units out there, be careful, many of these units still in use are analog meter movements and may or may not be calibrated correctly. When calibrating scale equipment we always recommend using an aviation-based calibration lab with an Airframe and Powerplant certified technician on staff or returning the unit directly to the manufacturer for calibration. Some units require specific calibration procedures, software access, and or adapters; to complete the calibration properly always audit your provider to ensure that the proper procedures and equipment are being used. Primary National Institute of Science and Technology (NIST) traceable certifications and test equipment are a must.
AC30-60 ™ Aviation Weighing System
Top of jack systems:
The standard aircraft scale is a top of jack, cell-based scale, where each jack point receives a cell-based transducer on the top of the jack. This system’s advantage is, it is very easy to use and level the aircraft during the weighing operation. The system is easy to transport, light weight, and easy to set up.
M2000-3-10CS Helicopter top of jack scale kit
Platforms are available in many weight ranges and sizes, these systems either use ramps or the aircraft can be jacked and lowered onto the platforms during regular maintenance. Platforms are easy to use and are a choice for many shops that do not have jacks for the many types of aircraft to be serviced.
Resolution and accuracy
As a general rule scales less than 10,000-pound capacity will measure in a 1-pound count and scales over that and up to 25,000 pounds will count in a 2-pound count. Large jet 50,000-pound scales will measure in a 5-pound count and so on. Always use a scale with the proper size and count resolution. The idea is to pick the right scale size and resolution for the aircraft type and accuracy needed.
He is an aviation journalist and the founder of Jetline Marvel. Dawal gained a comprehensive understanding of the commercial aviation industry. He has worked in a range of roles for more than 9 years in the aviation and aerospace industry. He has written more than 1700 articles in the aerospace industry.
When he was 19 years old, he received a national award for his general innovations and holds the patent. He completed two postgraduate degrees simultaneously, one in Aerospace and the other in Management. Additionally, he authored nearly six textbooks on aviation and aerospace tailored for students in various educational institutions.