Back course button

[Guest wake2rbulence]

where can I find the back course button? PMDG 737ng

[Mats_J 2]

Hi John Doe, ;-)Please, sign your posts with your real name as per the forum rules.If my memory serves me right the NG does not have a BC mode!Cheers,

[Guest wake2rbulence]

so how i'm i gonna have an approach on a backcourse rwy?cheers,emil

[marcom 139]

Well if you there are no other published instrument procedures available, you could fly the localizer for the opposite rwy until circle-to-land minima, enter a downwind for the opposite runway and land on it. If the minima prohibit a circle-to-land approach, you'll just have to land on the opposite runway!In good visual conditions you could simply fly a v

[Guest cugnolo]

Is this feature gonna be implemented in SU3?Davidhttp://forums.avsim.net/user_files/62069.jpg

[Mats_J 2]

Hi DavidI don't think so! As it's not on the real NG it shouldn't be on this NG.And BTW SU3 is already out. Next in line is the -800/900! :-jumpyCheers,

[Guest tmetzinger]

>Hi David>>I don't think so! >As it's not on the real NG it shouldn't be on this NG.>>And BTW SU3 is already out. Next in line is the -800/900!>:-jumpy>>Cheers,A back course approach is flown like any other non-precision approach - in LNAV with vertical guidance from VNAV/VS/LVL CHG.My tutorial covers a GPS approach, a back course approach is flown the same way.

[marcom 139]

I'm curious, TimAre LNAV approaches authorized in the US? Ie, using LNAV instead of raw data for a raw data approach?What are the minima for a BC approach flown exclusively in LNAV without raw data? I guess you could tune the localizer and fly the approach with LNAV and use the respective BC minima...

[Guest tmetzinger]

>I'm curious, Tim>Are LNAV approaches authorized in the US? Ie, using LNAV>instead of raw data for a raw data approach?>What are the minima for a BC approach flown exclusively in>LNAV without raw data? I guess you could tune the localizer>and fly the approach with LNAV and use the respective BC>minima...To be honest, I don't know the full answer. Having said that, I'll guess anyway.Approaches with a GPS/RNAV overlay can certainly be flown in LNAV/VNAV, provided the flight systems are meeting the required navigation performance.So, for VOR, NDB, GPS or RNAV performance I'm sure the transports fly these in LNAV, and probably have the navaid tuned so at least there's a pointer on the ND.For a LOC or BC, I don't know if there's an FAA requirement to monitor the raw data, but I'm pretty sure that the operators require it.I don't know if the loc display on the PFD automatically corrects for a BC, but one could certainly put up the raw data on the ND in APP display.

[marcom 139]

Tim,"So, for VOR, NDB, GPS or RNAV performance I'm sure the transports fly these in LNAV, and probably have the navaid tuned so at least there's a pointer on the ND."Correct, although operators require to have at least one pilot in VOR mode for the approach. Usually the pilot flying will be in map mode (for situational awareness) and the pilot not flying will be in VOR mode to doublecheck LNAV is flying the correct track."I don't know if the loc display on the PFD automatically corrects for a BC, but one could certainly put up the raw data on the ND in APP display."Good question! I'm sure Ian can answer this hint hint ;-)Regards,Mark

[Guest cugnolo]

I meant SU2 ver.1.3...Thanks,David

[Guest tmetzinger]

>Tim,>>"So, for VOR, NDB, GPS or RNAV performance I'm sure the>transports fly these in LNAV, and probably have the navaid>tuned so at least there's a pointer on the ND.">>Correct, although operators require to have at least one pilot>in VOR mode for the approach. Usually the pilot flying will be>in map mode (for situational awareness) and the pilot not>flying will be in VOR mode to doublecheck LNAV is flying the>correct track.>>"I don't know if the loc display on the PFD automatically>corrects for a BC, but one could certainly put up the raw data>on the ND in APP display.">>Good question! I'm sure Ian can answer this hint hint ;-)>Regards,>>Mark It occurs to me that the green projection on the map scree of the NAV1 radio also would help maintain situational awareness, assuming that the radial display is accurate for navigation.

[Qavion 19]

"Good question! I'm sure Ian can answer this hint hint "I'm having a little trouble interpreting my notes at the moment, Mark. Strangely, there is no mention of backcourse in the Autopilot/FD section, but in the ILS section it has this to say...."DCFS ControlsThe digital flight control system (DFCS) mode control panel (MCP) supplies runway heading data to the display electronics unit (DEU) for ILS displays (Sidenote: The DEU's provide the cockpit LCD displays with display data). You use the DFCS MCP course selector to set the course for approach.The DEU uses the course input and ILS deviation to calculate the airplane's deviation from the runway centerline. The DEU's compare the course input to the airplane's track to calculate if this is a back course approach. If the course input and airplane track are different by more than 90 degrees, the DEU's show backcourse ILS displays."To me, it is not clear if you can engage VOR/LOC for a backcourse approach. The A/P system is involved with the reversed data, but....???Hope this helps.Cheers.Ian.

[Guest tmetzinger]

>To me, it is not clear if you can engage VOR/LOC for a>backcourse approach. The A/P system is involved with the>reversed data, but....???>From a Continental ops manual:BC LOCALIZER

[Guest tmetzinger]

>The DEU uses the course input and ILS deviation to calculate>the airplane's deviation from the runway centerline. The DEU's>compare the course input to the airplane's track to calculate>if this is a back course approach. If the course input and>airplane track are different by more than 90 degrees, the>DEU's show backcourse ILS displays."Well, I can confirm from some pics that the PFD CDI is supposed to correct for reverse sensing on the back course of a localizer. In the PMDG it doesn't, and neither does the standby AI work correctly in the back course mode. I just flew from KCLE to KPTK to test the LOC/BC for RWY 27L.Of course, the ND in APP display mode does work correctly as long as the front course is dialed in.Hopefully, something to fix for the 800/900 update.