Hi folks,I think I discovered a bew bug! (Or 737's are different to ALL other Boeings!)Can you really activate an AFDS mode without either having a FD or an AP on??Let's say FD's are off aswell as both AP's. Now I press the ALT button and it lights up!! I'm pretty sure this is just another bug.Can you confirm?If it is a bug, how could this be missed in beta testing??Adrian

Er... you mean the light on the MCP goes on? Well, as far as I know that's just what is it: a light. Nothing more. This doesn't mean that mode is actually working!In order to see which mode is REALLY activated you ALWAYS have to look at the flight mode annunciator on the PFD! NEVER EVER look at the MCP if you want to know which mode you are in! Lights going on or off only indicate somethings can or cannot be changed/ selected/whatever. Like when the LOC and GS are on the APP button light will go off, meaning you cannot turn them off by using that button! The light being off does't mean the LOC/GS are disengaged!So in order to see which mode you are in always look at the PFD flight mode annunciators!

Hi Jeroen,I'm well aware of that technique. The FMA always announces what mode the master FCC is in.Anyhow, on all other glass Boeings, no light will go on in any MCP button unless either F/D or either AP is on.Let's look at it from a different angle:What's the purpose of a light going on without any F/D or AP on??(Other than to irritate the pilot)Regards,Adrian

It means that AFS has accepted your ALT hold request and as soon as you engage the AP the active pitch mode will be that. Nice to know not ? Also (making a very long story short, section 4.20 in AFM) if one F/D is off and the corresponding CMD switch is on then the F/D bars will NOT be displayed on the PFD at this side, however the AFDS system will be fully functional while the OTHER FCC unit will be used to send steering commands to the hydraulic servos which operate the flight controls. Finally : "in flight with A/P ON and F/Ds OFF, turning a F/D switch ON engages F/D in currently selected A/P modes.."Does this cover you ?VangelisPS. I find messages with titles like "another bug etc." and the general "air" of a 15000 hour NG captain somewhat uncouth and inapproriate in a public forum related to a any product.====================================== E. M. Vaos Precision Manuals Development Group www.precisionmanuals.com======================================

Adrian,please read these excerpts from the 737 FOM:"The mode selector switches are pushed to select desired command modes for the AFDS and A/T. The ON switch light illuminates to indicate the mode selection and that the mode can be deselected by pushing the switch again. While a mode is active, deselection can be automatically inhibited and is indicated by the switch light being extinguished""Autopilot Engagement Criteria:Each A/P can be engaged by pushing a separated CMD or CWS engage switch or A/P engage paddles. A/P engagement in CMD or CWS mode is inhibited unless both of the following pilot-controlled conditions are met: * no force is being applied to the control wheel * the STAB TRIM AUTOPILOT cutout switch is at NORMAL""Flight Director Display:Turning a F/D switch ON displays command bars on the respective pilot attitude indicator if command pitch and roll modes are engaged. If command pitch and roll modes are not engaged, the F/D command bars do not appear. The F/Ds can be operated with or without the A/P or A/T. F/D command modes can be used with an A/P engaged in CWS." This is how the 737 AFCS and F/D operates.Hope this helps to clarify your doubts.

I'm pretty sure this is just another bug Yeah I'm pretty sure it's another RTFM case ;-)Best Wishes,[h4]Randy J. Smith[/h4]http://www.rawbw.com/~bdoolin/shinault/Animation1.gifCaution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

Hi Vangelis,I'm not convinced. This would be the case if the FD was on and the AP wasn't. The MCP should be inhibited with both AP's and both FD's off!Maybe this was missed during development? Or there are different MCP softwares out there, with one that is very distracting to the pilots!!(I'm aware there are different MCP's available for the NG...)Regarding the two citations, well, nothing new there and nothing that relates to this topic..." I find messages with titles like "another bug etc." and the general "air" of a 15000 hour NG captain somewhat uncouth and inapproriate in a public forum related to a any product."Well, I'm pretty sure this is a bug! And there are a few more I noticed, so that would make it "another bug" right?You're right, I don't have 15000 hours on the NG and I'm not a captain. Are F/O's not allowed to comment? ;-)Regards,Adrian

Hello Enrico,I'm afraid I don't understand the relationship between your citations and my issue. My condition was: both AP's off and both F/D's off and then pressing a MCP button, which then actually activated a light.Greetings,Adrian

Well, show me where this is handled in the manual (both AP's off, both F/D's off and MCP buttons active) and I'll admit it being a RTFM issue.So, will you in return stop playing a pilot on this forum should you not find this info?Adrian

I don't post here often, but Randy... he's right. The mode should not light up unless one of the two are active.- Jeff Greth

You can activate an MCP mode BEFORE engage the A/P or F/D.It will simply be active when you engage the A/P or F/D.Greetings

Would you please share your reference?Thanks,Adrian

I also think he is right :)http://forums.avsim.net/user_files/90969.jpgWhen all Autopilots and all Flight Directors are off, I think you cannot select a AFDS mode :)Second bug: When disenaging all autopilots and F/D's all AFDS modes should be disengaged. This does NOT happen.

And another manualhttp://forums.avsim.net/user_files/90970.jpg

The same quote from the FOM regarding the MCP modes, where it doesn't state that the A/P must be engaged for a MCP mode button to be lighted when pressed.