Radar altimeter and HUD altitude display

[vctpil]

Hi,

 

When the ALT switch of the HUD control panel selected in RDR and if I select the needle of the radar altimeter below 0 to avoid altitude warning, only the barometric altitude is displayed on the HUD.

 

According to the flight manual § 2.12.5.4.7, this happening when the radar signal become invalid.

 

Is the HUD display is correct or is it a bug ?

 

Thanks,

Vincent

[VKing]

I'm pretty sure that if you turn your radar altimeter to zero, you turn it off. So no radar signal is given at all, which is an invalid signal for HUD display purposes, and it returns to barometric.

[vctpil]

If you set the radar altimeter below 0, the signal is OFF, so you should still be able to use the ALT RDR mode.

 

The manual says invalid, so maybe it is a bug ?