Passenger signs

[Avi]

...I think it's best to implement this 10300 feature on all models.

I was happy with it in the first place 

[Hardy Heinlin]

You prefer the logic used in 10.0.0?

[cavaricooper]

Hardy-

Please check re. changes to EICAS inhibit logic as well. Otherwise NO SMOKING will be illuminated for most of the flight.

Best- C

[Hardy Heinlin]

Sorry, I don't understand what you mean.

[cavaricooper]

Hardy-

As usual, I am clear as mud Sorry!

Once the SEAT BELT logic is correct, it ought to be possible to leave both signs in AUTO, only using ON for SEAT BELTS if there is Wx, etc.  Typically around TOD of sometime shortly thereafter, the SEAT BELT would go finally to ON and stay there for the duration.

Currently, the NO SMOKING extinguishes (and dings) at flaps up if left on AUTO.  This should never occur, as there are no commercial smoking flights (that I am aware of)... the aforementioned senior captain pulling the aforementioned CB being the exception .

Since all flights have been NO SMOKING, it is my understanding that the NO SMOKING logic has been changed to ALWAYS ON- for both AUTO and ON.  That being the case, and being that the only time EICAS is inhibited is when BOTH signs are ON.... I thought there was a logic change to allow for NO SMOKING to remain in AUTO and still inhibit the EICAS message for PASSENGER SIGNS/SEAT BELTS. 

I keep hoping JSW sees this thread and provides us his engineering expertise.....

Best- C

[Avi]

You prefer the logic used in 10.0.0?

No, I mean I was happy before you removed the 10,300 condition.
I tried to find (in my Alpha and Beta logs) when you did it but couldn't. Maybe you did it even before releasing the Alpha version with this system.

Cheers,

[Hardy Heinlin]

I thought there was a logic change to allow for NO SMOKING to remain in AUTO and still inhibit the EICAS message for PASSENGER SIGNS/SEAT BELTS.

I see no logic change. I keep it as it is until someone has any news.

[Britjet]

There is a mod floating about where the NO SMOKING signs memo doesn't appear if the switch is ON or AUTO, but not on all aircraft, I think. Not a big deal..

Peter

[John H Watson]

JHW and others, could you please comment? 

I can confirm that there were airline-specific triggers. I had a few wiring schematics from different companies showing this.

There are also airline variations in the modifications which hardwired the seatbelt signs on and/or changed the memo messages. I also noted that there were discrepancies between the manuals saying how the modifications behave and how they actually behaved 

My old airline didn't have the altitude input for the FSB/NS signs, but, for example, the Korean Airlines and British Airways schematics show (<10,300') altitude data going to the MAWEA on an ARINC databus from the Left or Right ADC (not sure how they are switched, or if the Centre ADC is involved).  Unfortunately, the Maintenance Manual checks for the system don't involve simulating altitude. They just involve shorting a certain MAWEA pin  to simulate the sign trigger.

The logic discussed on the beta forum (regarding chimes) included whether the PA speakers and certain parts of the ACESS system (Entertainment Services Controller, PA Controller, etc) were powered, although I don't remember how much of this was ultimately included in PSX.

(EDIT) Leaving no stone unturned... In the KLM Maintenance Training notes, the expression "L/R ADC BARO 1 CAPTS ALTM" is used ("Baro" = baro corrected altitude). This "CAPT ALTM" (only) doesn't make much sense to me:

The Captain's "Baro 1" signal goes to the MAWEA via the Captain's ADC Source Select Relay (Left ADC or C ADC).
The F/O's "Baro 1" signal goes to the MAWEA via the F/O's Source Select Relay (Right ADC or C ADC). I'm not sure why "CAPTS ALTM" only is used here. Perhaps this is just first choice of data? Say, the Left ADC databus goes dead and the pilot (or source select automatics where applicable) don't switch to the C ADC , the Right ADC (switched) data is used by the MAWEA.  On aircraft with only two ADC's the switching becomes much simpler 

Hope this helps
Rgds
JHW

[cavaricooper]

Much obliged...

C

Leaving no stone unturned... Hope this helps
Rgds
JHW

[Hardy Heinlin]

I can confirm that there were airline-specific triggers. I had a few wiring schematics from different companies showing this.

Good that you and Avi remember this through the years; I completely forgot what the source was :-)

There is one last slot free for an option checkbox on the Model > Programming page. I'll put the 10300 thing in there.


Cheers,

|-|ardy

[Hardy Heinlin]

The Captain's "Baro 1" signal goes to the MAWEA via the Captain's ADC Source Select Relay (Left ADC or C ADC).
The F/O's "Baro 1" signal goes to the MAWEA via the F/O's Source Select Relay (Right ADC or C ADC). I'm not sure why "CAPTS ALTM" only is used here. Perhaps this is just first choice of data? Say, the Left ADC databus goes dead and the pilot (or source select automatics where applicable) don't switch to the C ADC , the Right ADC (switched) data is used by the MAWEA.  On aircraft with only two ADC's the switching becomes much simpler 

If you remember, I've implemented a special logic to determine the ADC source in the MAWEA's altitude alert system. As documented in certain diagrams, it checks "all A/Ps off" or "muli-channel A/P in use" for using the captain's selected ADC, else it uses an ADC source based on stepper relay position and FCC R A/P engagement status.

Perhaps the same ADC is used for the 10300 check. And it's the baro corrected altitude as well, as the altitude alert system refers to QNH settings.

I think I'll just use that one :-)


Cheers,

|-|ardy

[John H Watson]

If you remember, I've implemented a special logic to determine the ADC source in the MAWEA's altitude alert system.

Thanks for the reminder...  After more stone turning....  I discovered that Crew Alerting Card does handle both the FSB/NS logic and altitude alert, but..... the data is handled in different ways. Boeing Schematic 31-51-12 actually shows the logic. The MAWEA monitors the ADC data busses and switches from the Captain's selected ADC to the F/O's selected ADC if there is no databus activity.

The schematics even show which programming pin needs to be shorted to ground to activate the "altitude" customer option   

Cheers
JHW

[United744]

I've seen the no smoking inhibit on Freighter aircraft (I have a DVD, and several more cockpit videos on YT) where there is no mention on the EICAS of "NO SMOKING ON". Only the state of the seatbelts sign is mentioned.

[Hardy Heinlin]

I've seen the no smoking inhibit on Freighter aircraft (I have a DVD, and several more cockpit videos on YT) where there is no mention on the EICAS of "NO SMOKING ON". Only the state of the seatbelts sign is mentioned.

Have you also seen the No Smoking selector position? If it's always OFF or AUTO, you can't tell whether the message is absent due to an internal inhibit.

[United744]

In this video, SEATBELTS is AUTO. NO SMOKING appears to be OFF.

https://www.youtube.com/watch?v=7g0xL88ebXs

[Hardy Heinlin]

Yes, but where in this video do you see the No Smoking selector position on the aisle stand?

[United744]

Yes, but where in this video do you see the No Smoking selector position on the aisle stand?

The first time you see the aspect of the flight deck from the ceiling is when you can see both switches.

[Hardy Heinlin]

At what time in the video?

[United744]

4:08