An Information About ADIRU

[Shermann 4]

Hi Everyone!

 

I Have a question ! what happen to the avigation system if the Adiru is in off position during the flight? As today i was flying from VHHH to VSTP and before landin i checked if all system were on and set and i noticed the ADIRU was in off position but the plane flew the route normally. Is this normal? 

 

Thanks 

[VLJ510 16]

I think under ADIRU failure the PFC (Primary Flight Computers) takes over.  Just a guess reading your post during a flight and looking at the overhead, I see the PFC is right under the ADIRU.  Again, its just a guess but I think that would be the redundant system for the ADIRU.

[Shermann 4]

It was not a failure i think i clicked it for error during climb or cruise! As ten i simply click it and was in on position. During the all flight i didnt have any messages warning me about the adiru was in off position and the plane followed the route perfectly so i was wondering if this is a normal behaviour or a bug.

[VLJ510 16]

Well it you turned it off, it was off and that would be a failure IMO as the system was failing to work.

 

Failure doesn't mean a rat has to eat the wires in half.

[VLJ510 16]

It was not a failure i think i clicked it for error during climb or cruise! As ten i simply click it and was in on position. During the all flight i didnt have any messages warning me about the adiru was in off position and the plane followed the route perfectly so i was wondering if this is a normal behaviour or a bug.

Just looked your answer up, the SAARU takes over when ADIRU is not working, although you should have gotten a "NO INERTIAL POS" message.

 

Secondary Altitude Air Data Reference Unit (SAARU)

 

SAARU is mentioned a lot on both FCOM's but FCOMv2 page 11.20.5 takes about if the ADIRU fails and this system takes over.

[tcas_climb 45]

If the switch is in the off position I know you won't lose the adiru in flight just in case it was switched off inadvertently, I don't remember if there's a time delay before it goes off in flight or it cannot manually be switched off in flight.

[EGLL77W 1,508]

If you turn it off in flight it has no effect. 

[Shermann 4]

Ok THat is what i wanna know ! Thanks to everyone