The document discusses the radio altimeters installed in the A320 aircraft. There are two radio altimeters that automatically activate when AC power is applied and provide continuous altitude measurements from lift-off to touchdown. Radio altitude is displayed on the pilot's displays and announces heights verbally to the pilots during approaches even if the loudspeakers are turned off.

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2. 2/17 Two radio altimeters are installed in the A320. They measure the aircraft height above the ground accurately . MENU

3. 3/17 There are no radio altimeter controls in the cockpit. Both radio altimeters come on automatically when AC power is applied to the aircraft. MENU

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5. 5/17 After a brief self test, the radio altimeters are in a standby mode during ground operations. They become active at lift-off and then operate continuously until touchdown. MENU

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7. 7/17 Radio height is always expressed as the number of feet between the bottom of the wheels and ground. Radio Altimeter data is supplied to several different users and is displayed on both PFD at all times below 2500 feet AGL. FMGC RADIO ALTIMETER DATA GPWS MENU

8. 8/17 Normally, Radio Altimeter 1 (RA1) height is displayed on the captain’s PFD and RA 2 on the First Officer’s PFD. RADIO ALTIMETER 2 RADIO ALTIMETER 1 Captain’s side First officer’s side MENU

9. 9/17 The radio altitude display on the PFD changes in color and size based on height above ground and / or proximity to the decision height.. MENU

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11. 11/17 This color coded digital readout is coupled with a white ground indication line and a red ground ribbon on the Altimeter scale. MENU

12. 12/17 The ground indication line and the red ground ribbon correspond to the raising ground level when the aircraft is descending. MENU

13. 13/17 As the aircraft descends below approximately 500 feet AGL the red ribbon appears at the bottom of the altimeter scale and begins to move up. MENU

14. 14/17 The white ground line moves from the bottom of the PFD towards the horizon. MENU

15. 15/17 At touchdown, the ribbon is in the centre of the altitude readout and the white ground line is merged with the horizon, as shown. These are designed to be used as a ground reference during autoland operations. MENU

16. 16/17 In addition to the visual indications, during approach, there is a synthetic voice for radio height announcement. MENU

17. 17/17 Depending on individual airline requirements, auto call-out announcements are made at pre-determined radio-altimeter heights. Example, “FOUR HUNDRED” at four hundred feet radio altitude. These call-outs will be heard even if the loudspeakers are turned off. MENU Module completed NEXT

18. 18/17 MENU Module completed NEXT Definitive text : At pre-determined heights, the announcement will be heard through the loudspeakers, even when the loudspeakers are turned off. For example, at four hundred feet, a call out of “FOUR HUNDRED” is made.

19. 19/17 LIST OF SUBJECTS EXIT GLOSSARY AUDIO FCOM RETURN OPERATION ECAM INDICATION GENERAL