Cargo system braking transport roller

Aircraft Engineering and Aerospace Technology

ISSN: 0002-2667

Article publication date: 1 December 2001



(2001), "Cargo system braking transport roller", Aircraft Engineering and Aerospace Technology, Vol. 73 No. 6.



Emerald Group Publishing Limited

Copyright © 2001, MCB UP Limited

Cargo system braking transport roller

Cargo system braking transport roller

Keywords: TRW Aeronautical Systems, Braking systems, Cargo

TRW Aeronautical Systems (Lucas Aerospace) has developed a new cargo system braking transport roller that claims to significantly increase system life and durability by only engaging at speeds above normal operation, unlike conventional braking rollers which are continually engaged.

Aircraft cargo systems utilize transport rollers to enable movement of aircraft cargo containers down the length of the cargo bay (longitudinal conveyance). A conventional braking roller employs constant braking at all loading speeds in both directions, which inhibits the function of the power drive units designed to move the cargo containers. This constant braking force increases wear, power consumption, and the risk of system damage as well as reducing the life of the power drive units.

TRW Aeronautical Systems' new braking transport roller can reportedly be set to a predetermined transport speed that engages the braking mechanism if exceeded, but allows non-restrictive movement of the cargo in either direction within the predetermined maximum transport speed. When the predetermined speed of the cargo containers is exceeded, the braking roller is said to automatically engage and apply braking resistance to slow the cargo containers' speed, protecting personnel from injury, and the aircraft and cargo from damage.

According to TRW, the self-contained braking transport roller easily installs into the roller track profile with two fasteners and functions without an external power source. The braking roller can be customized to airlines' particular needs by prodding predetermined braking ability in either one or both directions.

TRW's first platform for its new braking transport roller is Airbus Industrie's A340-500/600 aircraft. Airbus plans to install these rollers in the aircraft's lower lobe this summer.

TRW has also developed a next-generation cargo control system which it believes will significantly improve aircraft maintainability while reducing weight and life-cycle costs. Through the use of high-reliability, solid-state electronics and microprocessor technology, TRW has incorporated advanced diagnostic capability and simplified electronics in the new cargo control system, marking, it claims, a major technological step change for cargo systems.

The cargo bay area is an extremely harsh and complex environment, which can experience considerable abuse. Detecting and isolating a fault in the cargo loading system can be very difficult with conventional systems. TRW's new cargo control system incorporates advanced diagnostic capability reportedly allowing for greater accuracy and speed in fault detection and isolation, and greater efficiency in parts replacement. The diagnostic capability is said to constantly monitor all activity during the loading process and automatically records all faults caused by damage or malfunction, including intermittent faults, to non-volatile memory, which allows the system to retain fault data even after the aircraft power is turned off. The information is processed and displayed to the maintenance technician, showing not only the nature of the fault, but also the specific location of the line replaceable unit (LRU) on a graphical maintenance display.

An additional feature claimed of the cargo control system is the modular and quick-mount design of its electronic LRUs, allowing for rapid installation and replacement. The automatic identification of all system faults combined with the modular LRU feature will reportedly dramatically reduce maintenance turn-around-time compared with conventional systems. A damaged or faulty LRU detected during a loading operation can be signalled ahead via the optional aircraft central maintenance computer interface so that a spare LRU can be waiting on the ramp at the next stop.

According to TRW the LRUs also incorporate digital communication links, which are used to achieve significant reductions in system wiring complexity. This, they inform us, not only increases system reliability and reduces system weight, but also greatly simplifies installation and maintenance due to the drastic reduction in wire count. Further weight and reliability improvements are said to be achieved through the use of solid-state, surface-mount electronics throughout. These two features alone are estimated by TRW to eliminate more than 200 relays, 800 wires and 50 per cent of the system splicing required on a typical wide-body, main-deck installation.

This latest technology is believed to offer considerable cost reductions compared to conventional systems. In addition to savings in initial procurement costs, positive contributions to bottom line profitability will, we are told, be achieved year after year with lower spares cost, fewer repair actions, lower maintenance hours when repairs are required, and lower fuel costs.

Further details are available from TRW Aeronautical Systems. Tel: +44 (0) 771 441 2798; Web site: