PMDG 737 Discussion

Take off Trim setting takes into account an engine failure at V1. It results in a hands off climb at V2 or faster ON ONE ENGINE in the take off configuration (TO flaps and gear down). So on a light airplane with 2 working engines, once the gear is up it’s easy for the speed to want to shoot up. That’s why the AP could wanna pitch up higher than 20ºNUP. We just don’t do that when flying manually. It’s not a big deal and it happens all the time on short routes. Just let the speed build up and when you reach your acceleration altitude (1000ft on NADP2 or 3000ft on NADP2) bug up and retract flaps as the airplane accelerates.

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Ive found a in detail Video on youtube about Autoland in the PMDG 737 and the difference between fail passive and fail operational: https://www.youtube.com/watch?v=RiFm12TwugE

Im still a little confused about how much manual flying is usually done in the real 737.
Especially on landing and together with autothrust i have read different methods.

On takeoff i enable the Autopilot at 400 feet, and on landings i disable autopilot at 500 feet, and land with autothrust enabled (and with +5 knots).

99% of the landings are done manually. Most of the times, as soon as the airplane is configured for landing at about 3nm and at the correct speed, we will disconnect autopilot and autothrottle and land manually. Of course you can disconnect the autopilot earlier if you feel like it. Of course in real life, pilots landing 4 times per day couldn’t be bothered to do this every time.

Regarding autolands, let’s say we do one every 4 to 5 months (and in the simulator). We do it to stay current and of course when there’s actual CATII or CATIII conditions. There could be a heavy fog week where we’ll do 3 autolands and then we could have good visibility for the rest of the year and do the autoland in the sim because we forgot to do it in the airplane.

There’s really just nothing difficult about them. Arm approach mode and right then engage both autopilots (our callout is “APPROACH MODE ARMED, COMMAND A and B”). Then at 500ft RA make sure flare mode is armed and call “500 radio flare armed”.

FAIL PASSIVE: Disconnect the autopilot on main gear touchdown.
FAIL OPERATIONAL: Disconnect autopilot when turning off runway.

I don’t understand what people are struggling with…

In the 737 you never fly manually with auto throttle on except for climbing (usually after takeoff). Manual flight->Manual throttle. It’s not a 777. You can read about that in the manuals (FCOM, FPPM) which you can find online.

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Thank you for all of this information on descending. Is there a standard speed you normally descend at (not accounting for speed restrictions on the arrival, and assuming 250kts below 10,000)? Or do you normal descend at whatever the FMS calculates based on CI and (I assume) winds that are entered?

Related, do you feel the vnav speed control (term?) is accurate compared to the real plane? I asked based on your comment on smooth descent and not needing speed brakes. Most of the time when I am descending in VNAV mode, prior to the next speed constraint, the airplane will descend at constant speed, then level off to slow down, then start descending again. For example, if I am descending at 280kts, and I have a restriction at 12,000 of 250kts at waypoint X, in VNAV it will descent me to 12,000 about 3nm prior to X, level off to slow down (usually saying drag required so I deploy speed brake), and then at X will start descending again at new speed. Is this normal, or is there something else I should be doing to dampen this?

I am not a pilot, but on his Stream FlightDeck2Sim who is a 737 Captain just like @FormerSnail5736 he said that the VNAV is too conservative in his option, and is too shallow. Not sure what he means by that, but he says the PMDG VNAV needs a little more work (To be clear he said it was good, just needs a few tweaks).

It would be interesting to hear what @FormerSnail5736 has to say on this as well. Not to pit the opinions against each other just it is interesting. FlightDeck2Sim also seems to think the VNAV in the PMDG is a hybrid of 2 versions (FMC 1 and FMC 2) I think.

Is the 800 still on track for August?

I hope so, but to be honest I am getting fed up with the staggered release. I just wish they would put out the 600/800/900 all together.

I am sorry but bar the flight model I cant see what the difference is in the cockpits between the 7/8/9 maybe fuel tanks? But it is getting silly now IMHO.

I won’t be buying the 600 unless it is less than $30, once I get the 800 the 700 will be un-installed, and I dont think I will buy the 900.

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We descend at the speed given by the cost index (ECON speed), like you say. Now if for any reason we’re too high because ATC shortened our route or because they interrupted/delayed our descent, we will get out of ECON and select a faster speed in the DES page to get a steeper idle descent path that we can catch without the need for speedbrakes. Then there’s also the case where ATC tells us “Speed 260 or greater on conversion for sequence” which to our ears sounds a lot like “FLY 330KTS NOW!”.

The real airplane does a better job at descending on idle thrust. I’ve done descents in the real airplane where the thrust levers went idle at the TOD and didn’t add any thrust again until VREF+ADD. This doesn’t work in the PMDG mainly for two reasons.

  1. VNAV and LNAV use old bad code. They’re being improved and PMDG stated they’re releasing an update soon.
  2. The atmosphere in MSFS is messed up.

What you’re saying about deceleration points, yes, the real airplane will also level off to decelerate. VNAV PTH is a geometric line and deceleration segments are pretty much completely level. So the airplane will level off for a bit to decelerate to 250 below 10000 and it will level off to slow down to whatever speeds restriction you have in the legs page as per the procedure or ATC (for example 220B at the SLP or 180B on the turn to final at 10nm)

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It’s a marketing ploy by PMDG. They know the -800 is much more popular than the -700 but by releasing this version first, they made sure that pretty much everyone bought it because very few of us have the willpower to wait a year or so for the -800. When the 800 finally comes out, they are quite aware that many of us will also purchase this for full price. PMDG could have just as easily released the 800 first but with this strategy, they make much more money. It’s as simple as that. Given that pretty much the only substantive difference between the 700 and 800 are the exterior visuals and a couple of extra knobs in the cockpit, I’m getting my NGX fix flying the 700. The next purchase I make (and on this, I’ll wait until all the reviews are in) will be the MAX.

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There’s a lot to unpack here, but two things:

Um, what? The -800 should be out around August, and RSR indicated it’s already being beta tested. If, as you point out, there are only minimal modeling changes involved, why could it possibly take a “a year or so”? That makes no sense.

You will have a long wait for that. New exterior and cockpit models, new engines, new flight control systems, all on top of the fact that PMDG have not been shy in stating that their next aircraft will be the 777 and then the 747, then the “mystery” aircraft people have been talking about - that might be a Seven Five (reported RSR’s personal fave), or maybe an old school 727.

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We’ll see about the 800 about the 800 coming out “around August”. The 600 has even less changes than the 800 and PMDG has already announced that this release is now delayed.

Regarding the Max, who cares how long it takes? I don’t. I’m enjoying the 700 and assuming PMDG gets around to releasing some of the more substantive upgrades for it, I’ll be quite content until the Max finally rolls in.

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Speaking of NADP 1 & 2, on a #2, what is normally set for the thrust reduction altitude on the 73? I imagine it’d be either 1000 or 1500, but I don’t know.

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I’m personally very happy with the -700 and have no plans for the others (maybe the max when it arrives) but I’m not sure I agree with the pricing policy. Justflight bundled the Arrows together into a budget-friendly pack, and even gave you 25% off the Warrior if you already owned the Arrows. Even gave people who had thd 146 in X-plane a discount for that, iirc. Okay they’re not the same kind of aircraft, but the principle is the same. It’s not a great look, this kind of brazen profiteering, especially in these modern times where prices in general have skyrocketed. I like what PMDG do on the whole, but I’m not a fan of this.

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800 or 1000 depending where in the world you are.

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It’s set by default to 1500ft. You can see and modify this in the FMC. In the 737 the thrust reduction is automatic. It happens when you see N1 in the FMA. This complies with every airport that I have flown to. So effectively the only difference between NADP1 and NADP2 is where we accelerate. You can see the type of NADP in every airport in the GEN charts. If they don’t mention it you do NADP2.

NADP2 (the most common one):
-1000ft (end of the white line on the altimeter): BUG UP, Autopilot on.
-Retract flaps passing every flap manoeuvre speed with a green acceleration trend. (At the 5 mark, set flaps 1. At the 1 mark set flaps up)
-When Flaps up no lights: VNAV, Set Standard, After Take off Checklist

NADP1:
-1000ft: Autopilot on
-3000ft: BUG UP, Set Standard
-Retract flaps as per schedule.
-Flaps up no lights: VNAV, After Takeoff checklist

In some places one runway could be NADP2 and another runway could be NADP1. Then there’s places with non-standard NADPs. In Barcelona we bug up at 3500ft and there’s a whole set of guidelines on how to fly it (They’re VERY noise sensitive and punitive over there). And in Dublin we bug up at 1500ft. This is all in the GEN charts and also in an internal 2-10 page document we have for every destination called “airfield brief” where they gives tips and guidelines on how to fly to a certain place… what kind of vectors we should expect, common taxi routes, threats associated with ground separation, shape of the runway. Couldn’t live without it.

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NADPs have nothing to do with autopilot, or altimeter settings, etc…
How you fly them is completely up to you as long as you comply with them. And it might be different for each operators. What you are describing is your company’s procedures (I guess).

NADP 1:

NADP 2:

Once again altitudes might differ by local regulations but these are the ICAO standards. Altitudes are AGL.

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FWIW on the 787 the SOP in my airline is that the HUD gets put down during pre-flight and isn’t stowed again until exiting the runway at destination.

The only exception to that is if the HUD is U/S and the aircraft is dispatched under the DDG. In my close to 5000hrs on the aircraft I don’t think I’ve ever had that be the case so I’d say that’s pretty robust.

It goes without saying that it’s also useful for much more than takeoff and landing but there you go :man_shrugging:t3:

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Sure but in real life we fly SOPs, not regulations. Companies create SOPs that comply with regulations so that we don’t have to think about regulations all the time. We just fly the routines we train on. And that’s the best way to explain it to people using the sim with absolutely zero SOPs or methodology. I know that because I used sims at home for decades before jumping into the actual cockpit and found that every pilot follows exact procedures. You don’t just switch the lights off “when you remember”.

Of course from the regulations side an NADP doesn’t dictate when you engage an autopilot. In real life operations, and you know this if you’re on the line, an NADP SOP even dictates when we call approach on automatic handover departures.

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Anyone seeing more CTDs after the latest 737 update? I’ve done a lot of updates recently (mainly aircraft), and I have had 3 ctds using the 737. One airborne during a short flight and one after a 4hr flight just as I landed.
Cleared cache etc. Very annoying. 3 flights and 2 ctds.
I may have to try uninstalling some community add ons or rolling back drivers.
I didnt see any ctds using previous version.
Also using pmdg livery, same one I’ve used before on same aircraft option on similar routes as before with no issues previously.

Yeah, actually. I finally had a chance to fly the new update yesterday. I had a relatively uneventful flight from KPHX down to MMSD. Then in a new sim session, I tried a short flight from KBUR to KLAS. I had a CTD sitting on the ramp while editing some overlapping/duplicate waypoints in the FMC. Later, I decided to try the freeware KBUR scenery on Flightsim.to and had a CTD right after the “V2, Rotate” callout.

I then deleted the freeware scenery and made the flight uneventfully. But it’s worth noting that the first time I CTD’d at KBUR it was with stock scenery. These are my first crashes in some time.

However, and this may be relevant, on my flight down to Cabo earlier in the day, I had no less than 5 notices that my connection had been lost and eventually recovered. I can’t remember that ever happening. I had only lost connection a couple of times ever in nearly two years, let alone five times in one flight. So it’s quite possible my stability issues were related to data issues in the sim; anyone remember last fall when flying with live weather was causing CTDs for everyone? I have to wonder if something similar was going on yesterday.

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