What is the primary role of the PC-21 FMS?
A backup for managing communication with ATC and retrieving data in case of UFCP or MC failure.
What is the secondary role of the FMS?
To functions a secondary NAV source
What are the 3 main functions of the FMS?
1) Area Navigation (RNAV)
2) Backup tuning
3) Backup volume control
What provides the FMS with information on waypoints, nav aids and airports?
Navigation database.
What is involved in the RNAV function of the FMS?
1) Provides flight management capabilities
2) Provides flight management data for civil navigation
3) Provides customer database for storing defined routes/waypoints
What is involved in the backup function of the FMS?
1) Backup radio/NAV/transponder tuning
Note: Can only tune the transponder when the MC is not available.
What is involved in the backup volume control?
Control the volume levels of backup Radio/Nav/Intercom but ONLY when the MC is not available.
How is the FMS screen + keypad brightness controlled?
- DISPLAYS knob = Screen brightness
- PANELS knob = keypad brightness
- BRT key on FMS keypad
How can FMS be switched off?
By pressing the FMS button on the ELEC panel
- This turns off both cockpits FMS
Where is the scratchpad on the FMS?
The bottom line of the FMS
What does amber indicate on the FMS? What about green?
Amber = Alerting annunciation Green = Advisory annunciation
What are the two types of function keys on the FMS?
- General function keys
- Page selection keys
Are scratchpad inputs made from one FMS transferred to the other cockpits FMS?
Yes
What is primary means of controlling the COMM, VOR/ILS, TACAN and transponder units?
MC through the UFCP
Can the FMS dually tune the NAV radios and UHF/VHF radios with the MC?
Yes
Can the FMS dually tune the transponder or volume control with the MC?
No, only when the MC fails.
What sensors does the FMS receive navigation data from?
- GLSSU providing GPS (primary means)
- Two VOR/ILS receivers provide bearing data
- TACAN transceiver supplies DME data
- ADC provides air data
- IRS provides position and heading input
- PFD supplies reversionary SFD data
Where can FMS be displayed?
1) FMS display pages
2) PFD, MFD and the HUD
What is the primary display of the FMS data ?
HSI in the mad mode on the PFD.
How are the front and rear FMS powered?
By the BATT BUS.
On power up, is the rear FMS slaved to the front FMS?
Yes
What are the 4 phases of flight that the FMS computes and monitors?
- Enroute
- Terminal departure
- Terminal arrival
- Approach
Does the FMS transition between different phases of flight automatically?
Yes
When does FMS change between terminal departure to enroute?
When radial distance from departure airfield becomes > 33 NM or altitude becomes > 16,000 feet
When does FMS change from enroute to terminal arrival phase?
When radial distance from destination airfield becomes < 30 NM and aircraft altitude is < 15,000 feet above destination airfield elevation.
When does FMS change from terminal approach to approach phase?
- When intercept track angle to the final approach is < 90 deg
- The aircraft position is within +- 60 deg of the final approach course
- Approach has integrity
What are the 5 NAV modes of the FMS in order of priority?
1) GPS through GLSSU
2) DME/DME mode
3) VOR/DME mode
4) IRS mode
5) DR mode
What are the RNP and ANP ?
- Required nav performance and actual nav performance
- Actual nav performance must be within limits of RNP for that particular phase of flight, which the FMS calculated.
What formula and geodetic mode does the FMS use to calculated nav data?
1) Great circle formulae
2) WGS-84 geodetic mode of total earth
What overall nav data does the FMS compute?
The distance and the required track from the present position to the next waypoint in the active route.
Where are active waypoint shown in inverse cyan?
LEGS and PROGRESS pages
In case of loss of GPS, DME and VOR signals, what does FMS use?
Dead reckoning calculations
How does FMS switch between different nav sources?
Automatically by determining which is most reliable.
What does DR mode rely on?
- Heading, TAS and last computer value of wind for navigation.
- Accuracy will be degraded overtime.
How does FMS calculate the TTG to next waypoints?
Using current wind and groundspeed
Which page are system alerts shown? What colour are they in?
- MESSAGE RECALL
- Yellow
What colour are maintenance messages shown?
White on MAINT MESSAGES page
Where are status advisory messages displayed?
On the scratchpad in white.
What does an amber FMS MSG on the MFD mean?
Where is an FMS system alert.
When will FMS MSG annunciators turn off?
Once all messages have been used.
When do FMS power up?
When BATT 1 or BATT 2 have been powered up
What pages are used in flight plan creation?
1) RTE pages
2) DEP ARR pages
3) LEGS pages
What does flight plan creation include?
1) Entering of ORIGIN and DEST airport
2) Entering the callsign
3) Waypoint entry
4) Departure and arrival procedure entry
What can the FMS be used for in flight?
1) Modifying routes
2) Using the FMS holding pattern functions
3) Monitoring the route progress
What is a requirement on this course?
1) Entering the ORIGIN and DEST airport
2) Entering the FLT NO
3) Both can be entered on the RTE page
What buttons would you press if the ORIGIN and DEST airport for a flight are identical?
1) Press the ORIGIN LSK
2) Then press the DEST LSK
How can flight number be changed?
By typing the new callsign into the scratchpad followed by pressing the FLT NO LSK
What should be done after entering the ORIGIN and DEST airport? Which page is this done through?
Waypoints should be created through the LEGS page
What are the 3 priority sources for altitude data?
1) Barometer corrected altitude
2) Pressure altitude
3) GPS altitude
On FMS RADIO page, what colours do Cyan, Yellow and Green indicate?
Cyan = active and valid Yellow = active + invalid Green = standby
What does an ALTITUDE FAIL! system alert mean?
Primary ADC sourced input of barometer corrected and pressure altitude is lost
What does an amber FMS FAIL caution message on the MFD mean?
1) FMS has failed
2) FMS data is not correct
3) FMS is selected to OFF
What does PROGRESS page display?
Current RNP, ANP, PFD HIS scale and ETA for each waypoint.
What is the bottom line of the FMS display known as?
Scratchpad
Do the front and back FMS operate in tandem?
Yes
