Whats this sound ?

[Tomcat61]

When I am flying my 747 - 400, and about 50nm from landing, I get this sound, which sounds like a horn?

Is this some sort of navigational sound, as it is not your usuall beeping sound?
Thanks again....Tomcat61

[liran_bar]

hey tomcat....
I am not sure but I think the sound comes....
either from your wheels when the coming down or the lowering of your flaps.


Liran Bar, Israel

[Brett_Henderson]

I can't remember the specific situation, but at certain combos of :  airspeed, throttle/flap settings,, the computer "thinks" the gear should be lowered and sounds a warning,,    that may be it.

[Tomcat61]

Thanks guys, I just worked it out, its when I lower  Flaps.
Thanks again, Tomcat61

[fisharno]

I think that warning sounds when you set full flaps, with the gear up.

I usually try to deploy flaps in increments, with full flaps and gear down just before aquiring the ILS Localizer.