Flexible Shafts Support Boeing 737 Critical Operating Flight and Braking Systems

Oct. 18, 2012 - PRLog -- Piscataway, New Jersey --- S.S. White Technologies, the aerospace industry’s
leading performance-driven producer of aerospace flexible rotary shafts is
supplying the Thrust Reverser Actuation System (TRAS) flexible activation
shafts, variable bleed valve system shafts and rudder pedal control shaft on the
Boeing single aisle 737 commercial aircraft.

S.S. White flexible rotary shafts provide power rotational torque to the Thrust
Reverser Actuation System (TRAS) that open deflectors along the rear side of
the aircraft’s two engine nacelles.  This action redirects the engine thrust forward
working in parallel with the aircraft’s braking system to slow the aircraft down
after landing to insure a safe arrival. These same flexible rotary shafts also help
lock the TRAS system to prevent it from inadvertently engaging during flight.  

The variable bleed valve system consists of 11 flexible shafts and accompanying
valves and actuators. The actuators operate like doors that open and close to
adjust the bleed through the engine, essentially controlling airflow quantity to
the HP compressor. The system also prevents low pressure compressor surges
by bleeding compressor flow to the fan duct in response to a pressure signal from
the fuel control.

In addition, all aerospace flexible shaft products are designed to one of the
industry’s highest performance criteria by utilizing a unique computer modeling
program developed by S.S. White called PERFLEXION.  This program allows the
design engineers to fully model the behavioral characteristics of the wire bundles
within the shaft core and arrive at an optimum product that provides maximum
bending flexibility and torsional strength while allowing minimal torsional
deflection with up to a 30 percent improvement above accepted industry
standards.