kuobin

Hi E190 seniors:
From AOM,they said this button is to inhibit the landing aural warning in the event of dual radio altimeter failure.(when pushed ,a white striped bar will illuminate)
Then, there are 3 additional conditions that will make white striped bar extinguish :
1.Thrust levers are advanced >38 deg for two engs.OR

2.Thrust levers are advanced >57 deg for one eng.OR

3.Landing flap set without any landing gear down and locked.

Can anybody share me some plain explanation what is the reason behind these conditions.
Thank you so much.

STBYRUD

Sure, in case you turn off the gear warning, that condition will be reset during the next go-around or similar, and if the said conditions on the throttles aren't met then it will latest warn you again when you set landing flaps while not having the gear down and locked - actually very similar to the gear warning logic in a Piper Seminole or similar... I suppose the gear warning logic on the Embraer reverts to a purely thrust & flap lever position based mode - and to prevent you landing gear up after your first approach and the following goaround it turns the inhibitor off. Is that what youre asking for?

FE Hoppy

Treat the landing flap condition as a separate case.
You cannot inhibit the landing gear warning if flaps 5 or full is selected regardless of anything else.

The only time you can inhibit the warning is in the case of dual Rad Alt failure. The warning logic is

Rad alt below 700' or invalid and low thrust. ( the TLA angles you quote are correct for 190/195 but the 170/175 has different values)

As there are no markings on the throttle quadrant I regard the various TLAs as useless values and actively discourage students from remembering them.

If both RAs are inop the system assumes you are always below 700' and issues the warning whenever the thrust lever(s) transits from above to below the trigger angle.

At this point you can press the button to inhibit the warning and the stripe will illuminate.

The inhibit and warning are reset when the TLA(s) transit from below to above the trigger angle (with a little margin for hysteresis). The light in the button will go out.

Next time the TLA goes below the trigger angle the warning will sound again and you can inhibit again.

In the worst case if you kept inhibiting the warning without lowering the gear you would still get the warning when you selected landing flap.

kuobin

Thank you so much of both you, Since the E190 AOM does not clearly define meaning of the "on" and "off" of the white striped bar like Boeing way ,it is really hard for me to figure out the logic behind ,but now after your great explanation ,I got clue.