Crew Alerting System (CAS) Messages for Ground Spoiler System Status

Loss of valid pitch trim communication from the FCCs to the HSCU.

A horizontal stabilizer control channel has failed.

When a failure within the horizontal stabilizer system has occurred that does not prohibit movement.

<p>It indicates that rigging is valid for the current aircraft.</p> Signup and view all the answers

<p>They protect the horizontal stabilizer system with various power sources.</p> Signup and view all the answers

<p>The HSTS enters Backup mode if both FCCs are not available on power up, or if no valid input is received from either FCC for more than one second.</p> Signup and view all the answers

<p>The HSTS enters Normal mode when either FCC provides three consecutive frames of valid data.</p> Signup and view all the answers

<p>The HSTS operates in Maintenance mode only when all interlocks are valid, including a maintenance request from the CMC, a valid on-ground and stationary interlock from the FCC, and a valid FCS maintenance switch from the FCC.</p> Signup and view all the answers

<p>The HSCU is a dual-channel controller that operates in an active/standby configuration, interfacing with the primary flight controls system through the FCCs, and with the CAS and CMC systems through the aircraft MAUs, as well as the flight deck via the BACKUP PITCH switch.</p> Signup and view all the answers

<p>The additional bus from Channel 2 of the HSCU to the ACU provides horizontal stabilizer position information.</p> Signup and view all the answers

<p>The CAS messages indicate the status of the speed brake / ground spoiler system on the aircraft.</p> Signup and view all the answers

<p>The possible causes of the <strong>(warning) Aircraft Configuration</strong> CAS message include: the position of the FLAP Handle, SPEED BRAKE Handle, PARK / EMERG BRAKE Handle, Landing Gear Control Handle, Thrust Reverser Lever(s), GPWS/GND SPLR FLAP ORIDE Switch, Pitch, Rudder, and/or Roll Trim, or the Main Door not being in the correct position.</p> Signup and view all the answers

<p>The <strong>Speed Brake Auto Retract (caution)</strong> CAS message is triggered when the speed brakes (flight spoilers) are automatically retracted with the speed brake handle not in the stowed position and the Thrust Lever Angle (TLA) is greater than or equal to 90%, or when AOA limiting is encountered.</p> Signup and view all the answers

<p>The note indicates that certain CAS messages, such as <strong>Ground Spoiler</strong>, <strong>Speed Brake Auto Retract</strong>, and <strong>Speed Brake Extended</strong>, are not available when the aircraft is in FCC Direct mode or BFCU operation.</p> Signup and view all the answers

<p>The two possible causes of the <strong>Speed Brake Fail (caution)</strong> CAS message are: 1) a failure in the speed brake control, or 2) at least two pairs of spoilers being inoperative.</p> Signup and view all the answers

<p>The SPOST (Spoiler Panel Operational Self-Test) is used to exercise the powered systems associated with the spoiler panels. When successfully completed, it should result in flashing indications on the pedestal in the cockpit and 8 cycles of the pilot side stick shaker. Additionally, the FCC Alternate Mode (caution) and FCS Maintenance Required (caution) CAS messages should be present, the Flight Control synoptic should be stable (not flashing), and the FLT CTRL Battery voltage should be within acceptable parameters.</p> Signup and view all the answers

<p>The FCS Maintenance Required (caution) CAS message is due to the fact that the Flight Control System is not receiving inputs from the IRUs, ADS, and other unpowered systems.</p> Signup and view all the answers

<p>If the SPOST is in progress and does not successfully finish (indicated by less than eight stick shaker momentary activations and the presence of the FCS Maintenance Required (caution) CAS), then the FCC reports the SPOST as failed and posts an FCS Test Fail (caution) CAS. The most likely reason for this failure is removing power to any FCC channels while the SPOST is in progress.</p> Signup and view all the answers

<p>Once an FCC channel reports the SPOST as failed, it is latched until power is cycled to the FCC channels twice.</p> Signup and view all the answers

<p>The $ ext{FCS Maintenance Required (caution)}$ CAS message indicates that the Flight Control System is not receiving inputs from the IRUs, ADS, and other unpowered systems. This message is present at the end of the cockpit preflight check initiated SPOST.</p> Signup and view all the answers