3 hours ago, anavsun said:

What am I doing wrong? Why are there no 'RETARD' and 'LAND' alerts in the PFD when autolanding in KSJC?
 

 

You are far too fast as others have said, but reading this thread I was curious as I didn't think that would preclude the aircraft systems from an autoland.  Turns out that's correct - you DID autoland in this video!  You've got the fail passive autoland system "installed" in this plane, and it did exactly what it was supposed to do - you had a CMD autopilot annunciation (not single channel) with a white "Flare" addition under your green GS, indicating that flare is armed.  Right around 40ft, you can see the modes change - "Flare" becomes the active vertical mode, and the autothrottle mode changes to "Retard".  It was a flat landing and likely a firm one, but that's down to being 40kts fast 😉.

One thing- did you disconnect the autopilot or did that happen automatically on touchdown?  It should not be automatic, but maybe you were just that fast 👍.

But yeah, other than needing to get your speed under control, this all worked correctly.  That WAS an autoland.

5 minutes ago, Stearmandriver said:

But yeah, other than needing to get your speed under control, this all worked correctly.  That WAS an autoland.

answered in above post

Edited February 13, 20251 yr by pete_auau

47 minutes ago, pete_auau said:

One thing i noticed  is  that you havn't  armed the app mode

here is one utube plenty more on auto land

https://www.youtube.com/watch?v=Zl0EYkI0jZY&list=PLtFw-RsDhI85SH4R18hrswGV39hebQIyy&index=9

 

Approach mode was armed correctly because it's active in this video - note the FMA annunciations of "VOR/loc" and "GS".  Don't let the absence of the green light in the button on the MCP fool you - that's SUPPOSED to extinguish once approach mode becomes active.  That's telling you you cannot press the button again to deselect it.  👍

Just now, pete_auau said:

quick question will it autoland  with out pressing  the  app mode

No, but he did arm approach correctly; see my previous response.  We're posting over each other 😁.

9 hours ago, Area said:

It's starting to become clear, congratulations!!!

Uh, are you doing an ILS with autoland or ILS? In an "autoland" you have to disable the PA when rolling in RWY. "RETARD" is not announced but it is displayed on the PFD (watch your video at 01:11)

Thank you. Good catch regarding the RETARD at 01:11. I missed that one.

@AreaRegarding the VREF speed calculation, I did that in the PMDG tutorial. But since I'm testing on a really short route (about 30 miles from KSFO to KSJC) AND slewing, I didn't think it would apply.  Does the VREF and landing calculation still apply when the aircraft is slewed to a position in final approach??

Delete. Dupe.

Edited February 13, 20251 yr by anavsun

On 2/11/2025 at 7:46 AM, Stearmandriver said:

On an LNAV/VNAV approach, you can have an active lateral mode of LNAV with an armed lateral mode of LNAV which looks weird, but it's just the plane telling you what it will do on a missed.

Off topic...your mention of 'lateral mode' reminds me of a setting in the FMC.  I'm just wondering. Why is there a LATERAL OFFSET setting in the FMC? Would you know if this is in the real plane's FMC?  Isn't this what the HDG SEL button is for ie. to divert from the planned route. 


 

9 hours ago, Stearmandriver said:

One thing- did you disconnect the autopilot or did that happen automatically on touchdown?  It should not be automatic, but maybe you were just that fast

I disconnected the autopilot. I thought that is the reason why the disengage autopilot button is larger than other buttons in the Collins MCP because autopilot can only be manually disconnected.  Are you saying that autopilot can be disconnected automatically? How?  Is there a setting in the FMC to disconnect it automatically?

10 hours ago, martinboehme said:

You're too fast. The speed selector on the MCP is set to 190, while a typical approach speed for flaps 30 is around 140 knots. Note also that the autothrust is limiting the speed to 175 knots, as that's the limit speed for flaps 30. (This is also why the "B" is flashing in the MCP speed window.)

Good point. Thank you.

Maybe that's an "8" (eight) and actually not a "B"?   The only "A" and "B" notation I'm aware of is those that appear as suffixes in the FMC's altitude restriction column.  Correct me if I'm mistaken but I think an "A" in the altitude restriction column means the aircraft has to be above the altitude indicated and likewise a "B" means it has to be below the altitude indicated.

1 hour ago, anavsun said:

Maybe that's an "8" (eight) and actually not a "B"

It looks like an eight because it's a seven-segment display, but I think it's supposed to be a "B" for "below" (indicating that the speed the aircraft is actually maintaining is below the speed you selected in the speed window). There's also an "A" that can appear here to indicate that the speed the aircraft is maintaining is above the speed you selected.

1 hour ago, anavsun said:

Correct me if I'm mistaken but I think an "A" in the altitude restriction column means the aircraft has to be above the altitude indicated and likewise a "B" means it has to be below the altitude indicated.

Yes -- to be precise, it's "at or above" and "at or below".

3 hours ago, anavsun said:

Regarding the VREF speed calculation, I did that in the PMDG tutorial. But since I'm testing on a really short route (about 30 miles from KSFO to KSJC) AND slewing, I didn't think it would apply.  Does the VREF and landing calculation still apply when the aircraft is slewed to a position in final approach??

You don't need to compute the approach speed using the APPROACH REF page -- you can look it up from a table. This is contained in the "Performance Inflight" section of the QRH (I found one for download here).

But you do obviously need to fly the approach at the correct speed. Too fast and you risk an overrun. Too slow and you risk a hard landing, a tail strike, or even a stall.

2 hours ago, anavsun said:

Why is there a LATERAL OFFSET setting in the FMC? Would you know if this is in the real plane's FMC?  Isn't this what the HDG SEL button is for ie. to divert from the planned route. 

Yes, that page exists on the real aircraft and is used for this:

https://en.wikipedia.org/wiki/Strategic_lateral_offset_procedure

1 hour ago, martinboehme said:

You don't need to compute the approach speed using the APPROACH REF page -- you can look it up from a table. This is contained in the "Performance Inflight" section of the QRH (I found one for download here).

But you do obviously need to fly the approach at the correct speed. Too fast and you risk an overrun. Too slow and you risk a hard landing, a tail strike, or even a stall.

Thank you for the QRH.

In viewing other YouTube videos (I have yet to view the videos suggested above), some YouTubers mention "go to flap 5 speed" without mentioning other info like weight which is noted in the QRH.

Do the flap speeds for the 737-800 (from the source referenced below) apply for PMDG's versions of the 737 (736, 738...)?

• Flaps 1: 250 knots
• Flaps 5: 250 knots
• Flaps 10: 210 knots
• Flaps 15: 195 knots
• Flaps 25: 190 knots
• Flaps 30: 175 knots
• Flaps 40: 162 knots
Source: https://aviationinfo.net/boeing-b737-800-approach-speeds-standard-approach-profile

Do these flap settings translate to actual degrees of an angle ie. 1 is 1 degree angle?? It doesn't seem like much at all!

Other YouTubers commented to follow the guideline on the speed tape when landing. When the speed tape says '1', then bring down the flaps to '1', when the speed tape says 'UP' bring the flaps 'UP', but I don't think this works because it may say 'UP' and that doesn't make sense when landing.

25 minutes ago, anavsun said:

Do the flap speeds for the 737-800 (from the source referenced below) apply for PMDG's versions of the 737 (736, 738...)?

Yes.

Note that these speeds are the flap limit speeds - the maximum speeds at which you can fly with a given flap setting.

The speed marked on the speed tape (e.g. with a "1") is the flap maneuvering speed for the currently selected flap setting (and your current weight). This is the minimum speed at which you can fly with this flap setting and perform turns up to 30 degrees of bank.

In other words, "UP" is the slowest speed at which you should fly with the flaps up. To reduce speed further, you would need to start extending flaps.

25 minutes ago, anavsun said:

Do these flap settings translate to actual degrees of an angle ie. 1 is 1 degree angle?? It doesn't seem like much at all!

Yes, these are degrees, at least approximately.

Keep in mind that the flaps not only angle downwards but also extend backwards, thereby increasing the total wing area. In addition, the leading edge slats extend with the flaps. Taken together, there's an appreciable effect, even at "just 1 degree".

As I recall, standard procedure though is to go straight from flaps up to flaps 5, as the limit speed for both is the same anyway. (@Stearmandriver please jump in if I'm getting this wrong.)

Edited February 13, 20251 yr by martinboehme

4 hours ago, anavsun said:

Off topic...your mention of 'lateral mode' reminds me of a setting in the FMC.  I'm just wondering. Why is there a LATERAL OFFSET setting in the FMC? Would you know if this is in the real plane's FMC?  Isn't this what the HDG SEL button is for ie. to divert from the planned route. 


 

That creates a parallel offset from your active route, and it has a few uses.  Someone posted the SLOP technique in oceanic and that's one use, but we'll make an effort to stay in LNAV whenever possible when in oceanic airspace to guard against gross navigational errors, so we'll usually perform weather deviations in oceanic via an offset as well.  It's how ATC in oceanic airspace is accustomed to using clearance to deviate: "cleared to offset up to 30.0nm left of track" for instance. 

I've also requested and used an offset when closely following an aircraft on a domestic airway and getting repeatedly bumped by their wake.  I'll request a shortcut that diverges me from them if there is one, but if we're both on a long straight segment with no good option to point elsewhere, requesting a small offset upwind of course will solve the problem. 

There'll be other uses for it, that's just what comes to mind now.  Just another tool.

4 hours ago, anavsun said:

I disconnected the autopilot. I thought that is the reason why the disengage autopilot button is larger than other buttons in the Collins MCP because autopilot can only be manually disconnected.  Are you saying that autopilot can be disconnected automatically? How?  Is there a setting in the FMC to disconnect it automatically?

No the autopilot will not disconnect automatically on touchdown.  It happened so quickly after touchdown on your video that I was curious if it had happened automatically since it shouldn't.  But if you disconnected it manually, then that's all correct 👍.

 

4 hours ago, anavsun said:

Maybe that's an "8" (eight) and actually not a "B"? 

Martin is correct about the A and B in the MCP speed window.  He's also correct about the flap speed bugs.  To simplify, when a tutorial tells you to bug the flaps 5 speed for instance, you'll set your speed bug to the green "-5" on your airspeed tape (which will appear when you select flaps 5).  This is the slowest safe maneuver speed for that flap setting and differs with weight, which is why they're dynamically calculated and not just static markings.  A common call from a Pilot Flying to a Pilot Monitoring would be "flaps 5, bug 5" for instance.  Before slowing below the green speed bug, you should select the next notch of flaps.