B777 question: Chime Inhibit

[Jeroen Hoppenbrouwers]

Question for the 777 drivers out there.

I am controlling a SATCOM unit that we're going to stick into a 777.  The SATCOM unit generates SELCAL messages on EICAS which come with the associated ding-dong chime.

Is the aircraft itself capable of finding out that it is in a critical phase of flight and that it should suppress EICAS messages, and especially sounds, that are not relevant for the safe conduct of the flight?

What happens to the SELCAL message and chime if you're in the middle of the takeoff run and Inmarsat or HF SELCALs you?


Jeroen

[John H Watson]

My 777 notes say that comms messages are inhibited during takeoff and landing, except for CABIN ALERT. Takeoff thrust on the ground initiates the takeoff inhibit. RA below 800' initiates the landing inhibit.

However, I can't find any specific reference to the inhibiting of the hi/low selcal chime or audio panel lights.

I find it hard to believe that there would be no chime inhibit when even Master Cautions are inhibited during takeoff (>V1).

Rgds
JHW

[Jeroen Hoppenbrouwers]

Got this out of the flight manual in the mean time:

"Communication alert messages and the aural chime are inhibited on takeoff from the time either engine is advanced to takeoff thrust through 400 feet RA or until 20 seconds after rotation."

"Communication alert messages are inhibited on descent from 800 feet RA until below 75 knots groundspeed."

For me this means that *SELCAL and *SATCOM MESSAGE will be suppressed during these critical phases of flight; but the yellow SATCOM and SATCOM VOICE will still get through (they don't come with a chime, though).

I believe this is what I needed to know.  The aircraft itself knows exactly when not to pass the messages to the pilots.

The SAT1 CALL and SAT2 CALL lights are not in the pilot's primary field of view and should not pose a problem when they light up.  Nothing will happen until the phone is picked up and this needs pilot action in any case.


Hoppie

[Jeroen Hoppenbrouwers]

Stuff completed! We integrated the thing into a 777 and it all ran like clockwork.


Flight deck integration verification on United N77006 in Newark.


Slightly important: our 4-channel Iridium blaster does not blow the
ship GPS out of the water (which is not trivial to ensure).

Sweet revenge ... I never wanted to become a pilot, I wanted to become a flight engineer. When I got canceled by the two-crew flight decks, I had no other choice than to become an avionics engineer if I wanted to play with this gear.   :-)


Hoppie

[John Golin]

Great stuff Hoppie!