small issue: FMC message indicator

[Guest ilh]

When I clear a message on the FMC with the CLR key, shouldn't the FMC message anunciator on the panel also go out? Do I really need to clear the message in both places?Lee Hetherington (KBED)

[Guest amerton]

Hummm. not too sure...We'll check that.anthonyAnthony MertonPrecision Manuals Developmenthttp://www.precisionmanuals.com

[Tabs 2,790]

Paging Ian Riddell... ;) I know it is this way in the 757/767 and it'd probably make sense for it to be that way in the NGs, kinda redundant to make the pilots clear the same message twice...Ryan

[Mats_J 2]

Another thing relating to the above. Is it possible to clear the right CDU from the ordinary CDU as well. I dunno how this is done in the real thing. But as we are usually flying solo it would be great if both could be cleared at the same time. Minor thingie though... ;-)Regards,

[Guest Ian_Riddell]

"When I clear a message on the FMC with the CLR key, shouldn't the FMC message anunciator on the panel also go out? Do I really need to clear the message in both places?"Hi, Lee.Looking at the simplified wiring schematic I have in front of me (of the ASA on the instrument panel), I see there is no remote reset function... just FMC Message/Fail inputs (from the FMCS's via transfer relays: the transfer relays are controlled by the "Both On Left/Normal", etc, switches on the overhead panel)).However, resetting the Captain's ASA will reset the F/O's and vice versa.... If it's a chore... just get your F/O to reset it for you ;-)The Boeing Maintenance Manual includes a check for the ASA, which involves pushing the reset button, then clearing the scratchpad. I don't know why.Cheers.Ian.

[Guest lbb]

Well, wouldn't that suggest that if you clear the scratchpad first, the FMC alert light would extinguish, thereby making it impossible to test the reset button as such?I personally am convinced - a gut feeling, probably mostly based on my own irritation and confusion over an illogical operation - that the light should go out if you eliminate the message, however from the operating manual for the 3/4/5 it is very hard to actually prove that. It only says this:The amber FMC alert light illuminates whenever an alerting message is displayed in the CDU scratch pad. If you take this literally, the moment you remove the message the condition for illumination of the FMC alert light is gone and it should therefore extinguish.Apart from that, as I have indicated in the past, there is a difference between alerting messages and advisory messages. The latter shouldn't illuminate the FMC _alert_ light at all.And finally, where is the MSG light on the CDU itself?Leo Bakker

[Guest Hagar]

From my work with automation and instrumentation, I`m used to this. If you have several pieces of the same equipment (FMC for example), usually there is a central warning lamp for all of them, placed on the central control board where your attention usually are. When the central warning lights up, you go looking for the unit setting off the warning, fix the problem, the reset what I use to call "Group Alarm Button". Often you can`t reset it before the problem is solved.EDIT: Guess I just said the same as you said, Leo. Bad habits I have :)

[Guest amerton]

I'll ask a 737NG driver and keep you posted...stay tuned...anthonyAnthony MertonPrecision Manuals Developmenthttp://www.precisionmanuals.com

[Guest amerton]

And the answer is.... (drumroll)...it does clear the panel announciator when you clear the message on CDU...2 pilots confirmed this.I guess we now have it on our list of outstanding "thingies" ;-)anthonyAnthony MertonPrecision Manuals Developmenthttp://www.precisionmanuals.com

[Tabs 2,790]

Cool - we was right Lee! ;)Ryan

[crvm 0]

Leo, You are right about the panel. There are 3 types of messages shown in the CDU stratchpad, these are; Alerting messages Entry error messagesAdvisory messages Only alerting messages will illuminate the panel along with being displayed in the strachpad and illuminate the MSG while the other 2 message types will display in the scratchpad AND illuminate the MSG on the CDU itself.[h5]Best Wishes,Randy J. Smith [h4]P M D G 7 3 7 NG[/h4]http://img.villagephotos.com/p/2003-8/196432/mineimage.jpg [h3] Realism on the horizon [h5]AMD XP 2200 |MUNCHKIN 512 DDR RAM |ECS[/b ][i] K7S5A MB[/i] |GF2 MX 32 MEG and still runs GOOD!|WIN XP PRO |MITSUBISHI DIAMOND PLUS 91 19"[/h5]

[Guest ilh]

Thank you.Lee Hetherington (KBED)