Modern aircraft typically store their primary fuel tanks within their wings to achieve balanced weight distribution. This design enhances stability while providing additional space for cargo storage. The Airbus A380 aircraft, for instance, can hold up to 320,000 liters of fuel across 11 main tanks, with 5 tanks located in each wing.1 Fuel is transferred between these tanks to maintain the aircraft’s center of gravity, ensuring it remains balanced during flight.
Aircraft wings are reinforced by wing ribs, which help prevent fuel movement as the aircraft maneuvers. Additionally, these ribs contribute to the wing’s aerodynamic profile and serve as a base for the aircraft’s outer skin. The equal spacing of ribs along the wing’s span is critical for structural integrity and performance. The fitting holes in the rib sections of a wing box play a vital role in both wing assembly and alignment.
Laser Alignment Solution
When a fuel alignment check system was sought for the Airbus A380 aircraft, Pinpoint proposed a custom laser alignment solution. This system accurately measures the centerline-to-centerline positions of the fitting holes in the wing box ribs while assessing the angular orientation of the rib due to deflection and surface bowing.
Fuel Alignment Check Equipment
The A380 Fuel System Alignment system included a:
- Laser transmitter that creates the datum line for measurement by projecting a laser beam from one rib section to the receiver.
- Receiver that detects where the laser reference beam strikes it. The position of the laser beam reflects both the relative centerline location of two holes and the angular deflection of the rib panel surface to which the laser is attached. The receiver for this application was modified so that the laser beam could be detected over a much wider range of motion.
- Microgage 2D display offering precise readouts of the laser beam’s position. It updates alignment in real time and offers a computer interface and software options for additional functionality.
How it Works
This illustration shows how the laser alignment system mounts into fittings on the rib panels. The positioning of the laser and the receiver can be directly compared to assess their relative alignment. Any misalignment is identified as a combination of centerline position and angular deviation at the fitting where the laser is mounted.
Typically, three rib sections are compared at one time to detect centerline errors and angular deflections in both the forward-to-aft axis and the top skin to bottom skin axis.
This custom solution can accommodate rib section holes measuring between 120 to 145mm in diameter, as well as smaller holes ranging from 75mm to 50mm for future applications. The wall thickness of the rib panels varies between 3mm and 10mm.
Pinpoint’s laser alignment solution automates the aircraft structure alignment, providing fast and accurate results with reduced tooling investment. It also is user-friendly, intuitive and durable to endure heavy use in both field and factory settings.
Other Custom Solutions
With a range of alignment technologies and accessories, combined with engineering expertise, Pinpoint develops special solutions tailored to particular alignment applications and applications. Some of the most interesting include hydroelectric dam monitoring, heavy large gantry alignment, helicopter gearbox alignment and checking steel hull plates for ships.
