Vagabondo

Well I suppose technically the aircraft is in a sideslip condition when decrabbing. However, for simplicity, I am purely writing in context of Boeing's description of the techniques in the FCTM and their definition of crabbed and sideslip landings.

Sideslip in a 737 is a late final transition from crab to wind down attitude within in the last few feet before the flare. The result is that the aircraft touches down on one wheel first. This is not that uncommon, many pilots decrab into a sideslip and flare and touchdown wing down. The standard decrab is arguably simpler to perform, but the advantage with sideslip is that that it is easier to control lateral drift during the flare to touchdown.

Judging by the numbers, NGX has been their biggest hit by far. NGX makes so much sense for sim enthusiasts as it is juicy in terms of complexity, systems and automation all wrapped up in a narrow body shorthaul package with enough variants and options to keep everybody challenged. I imagine that PMDG will see the sense in keeping NGX or future version of the simulation of the NG and MAX going as a company staple B)

Hi Jeff, The use of the LNAV/VNAV arm is not SOP at my company. However, generally, once we have received the clearance for an SID LNAV and VNAV are armed. If we receive a clearance for a heading, then only VNAV is armed. Every now and then I will choose not to arm VNAV/LNAV and do it the 'old fashioned' way.

Hi WilloW, You should checkout the Landing section of the FCTM (Flight Crew Training Manual) included with NGX. In there you will see that if you land fully crabbed, you should expect the aircraft to veer off the centreline at touchdown. Boeing themselves describe this and expect the pilot correct and regain the centreline expeditiously using symmetrical braking and reverse. There are other options for landing in a crosswind, such as de-crabing during the flare or adopting the sideslip method before the flare. They generally have their pros and cons. For example, in strong crosswind and dry conditions, perhaps landing fully crabbed isn't the best option. By the same token at the crosswind limit perhaps the sideslip method won't be sufficient without introducing crab too. Maybe in strong gusty crosswind conditions decrabbing in the flare could perhaps be the least stable. You get the idea I hope. With all that in mind, select the technique most appropriate for the conditions so that the use of autobrake should really depend on the desired stopping distance and turnaround time, taking into account the runway conditions and other factors that affect landing performance.

Funnily enough, landing a 737 is similar to a tailwheel three point landing, insofar as one simply smoothly sets the landing pitch attitude whilst simultaneously smoothing reducing thrust, holds that attitude and effectively waits for touchdown.

Not that many. In normal ops it is set to 25 by default. I use it for 15 or 10 degrees occasionally at cruise when navigating around thunderstorms - just in case we run into turbulence when reasonably close to the amber bars and also because wide turns are generally a better fit with navigating to an offset. All non standard engine out take off procedures require a 15 degree angle of bank to ensure maximum climb gradients in a turn. Our SOP is that all EOPs (standard and non-standard) are to be flown 15 degree. There is no SOP for the use of the bank angle selector but some choose to set it before takeoff and some leave it to when it is required - which is practically speaking, outside of a simulator training, never so far.

I seem to recall that you need to then send a support ticket with the order number (or something). You will then get a support response with the valid download link. I can't recall for sure, but the instructions are defo on the PMDG site or support site.

Quite right. What can and most usually does lead to the reverser light illuminating in the real aircraft, is not smoothly stowing the reverse levers. If the light comes on in such a case, usually simply re-activating reverse thrust and re-stowing clears the problem.

I'm a real Luddite. IMHO, the best avionics suite for the 737 was the EFIS Classic (except for the EIS, that was pretty lousy). The NG screens can provide too much distracting, attention sucking and non-essential information with an irregular visual scan pattern depending on what is selected. The Classic was an excellent blend of analogue with the benefits of EFIS, with a standard six pack scan for the most part. The best 737 I ever flew was a 400 EFIS with 200 engine instruments. The MAX configuration looks like just more visual noise :(

Interesting video. Good call to go around, but I got the distinct impression by the delay in making the call that they hoped it would become visual again which is pushing it a bit as they were already below minima. The calls are bit muffled so it is difficult to be sure, but the go-around it self seemed to be a little uncoordinated. You can see the speed window open up prematurely, probably due to A/P engagement - this can be a bit of a gotcha with such a high workload. In my opinion it is generally better to hand fly to flaps up clean speed as per Boeing guidance. The PF calls for heading 090 so he didn't seem to notice the speed window. The PM starts to bug up when he was interrupted to set the heading a second time. He didn't go back to the speed, so perhaps it was at or above flaps up speed, but I didn't get that impression from his movement. The PF calls for flaps up with no indication that he noticed the speed window. I have no idea why the FLT CONT master caution annunciation, but they seemed pretty quick in cancelling it without calling or identifying it!

That is a very good and thorough review with a great result mate - not a single negative point in the conclusion! Good job

Interesting. I wasn't aware how complicated this was before I started with the Boeing. I believe those ADs are now out of date. I could be wrong, but all NGs have been modified with reliable auto-shutoff center tank fuel pumps. I don't really know the history of this, but suffice to say that the PMDG manuals describe different before takeoff procedures depending levels of compliance to this AD. The up to date procedure is the one entitled "Alternative Method of Compliance" which is the simplest and makes the above table redundant. The logic of the center fuel pumps with PMDG should be that they auto shutoff after a short time with the LOW PRESSURE light illuminated. If fuel is added, they should require turning OFF then ON to extinguish the light. This is unlike the behavior of the main tank pumps. In the most basic form the current procedure is - Ground: Mandetory OFF if <460kg. All other phases of flight: Mandatory ON if >450kgs. Otherwise, as required.

Ah, that's something different. The alternate technique applies to climb and descent. On approach with VNAV, the MDA+50' (or more than 50' if more than 3 deg) is set on the MCP around 2nm before the FAF and then to missed app alt 300' below the missed app alt. That is standard Boeing as per FCOM1, Normal Procedures, Amplified Procedure, Instrument Approach Using VNAV and Supplementary Procedures, Automatic Flight, RNAV (RNP) AR. BTW, sorry if I over explain, I know you know your stuff, other readers may find this interesting too.

Yeah, I have not come across it myself yet, but the case where the the arrival specifies something like 8000A and ATC give a clearance for 6000, one still has to be at least level at 8000 at the waypoint unless ATC have specifically used the phrase "descend unrestricted" in the clearance. A potential gotcha for sure. As per Boeing's recommended practice, we always set the MCP altitude for the next restriction. Interestingly, I don't recall ever using the "alternate MCP altitude setting technique" (see the FCTM). In the real world, VNAV can be a little bit left of field at times with uncommanded level offs, disconnections, FMC vertical path disagreements and having to cross a restricted a waypoint before ALT INTV will allow the descent to continue (amongst other things). Regardless of which technique is used, there are potential gotchas/complications, so there is no alternative to maintaining good SA and CRM at all times

Personally, in the real aircraft, I seldom use SPD INTV in the descent. My personal philosophy is that if VNAV PATH isn't doing the job I want or if the clearance changes from the FMC profile, then dump VNAV altogether and use LVL CHG or V/S. If staying in LNAV I'll re-select VNAV once back on path and speed.

Spot on for John and Kyle Except on the ground, engines shutdown, APU on with with > 450kgs when using a single center tank pump (the left one) will prevent an imbalance. FWIW with regard to fuel balancing in general, in reality and in flight, main tank imbalances in the NG only really happen when single engine. The Classic however was a different beast, just about every flight could utilize fuel balancing to some degree. It seems the EECs in the NG do a great job compared to the Classic's PMCs. Also, checkout the QRH LOW FUEL checklist for another not too uncommon reason to use the crossfeed in flight.

I presume you mean 1000lbs or 450kg? If so, that is sort of correct. More accurately, the center pumps are not to be used with less than 450kg in the center tanks on the ground. In either case (air or ground), the main tanks must be scheduled to be full (read 'planned' or 'intended') with more than 450kg in the center tank - in other words the center tank pump switches must be on with more than 450kg. This can lead to Master Caution Fuel annunciation on takeoff when the fuel sloshes to the back of the tank, which should be briefed to prevent an unnecessary RTO! Some guys just switch the centers off for take off with less than less than 1000kgs to prevent this.

I would say that regardless of the trip length the ToC wind should be entered as the CRZ WIND in PERF INIT and the LEGS, RTE DATA pages updated with the forcast winds where the differ significantly from the ToC. Then the FMC can calculate the most efficient speeds for each leg with the most accurate ETA and arrival fuel. If you were to enter an average wind in PERF INIT and leave it at that, I reckon the FMC would calculate speeds based on that wind, any significant difference in enroute wind from the forecast could affect all the predictions. That's my opinion, but any overall loss or gain over a number of flights is probably immeasurable and would thus remain conjecture :(

We don't do RNP AR and I am not specifically trained and thus I confidently assumed...incorrectly Good info and thanks for the correction Kyle.

Are you saying that with LNAV you are flying offset from the magenta line or the extended runway center line?

The only RNPs I have come across for RNAV approaches are 0.3 and 0.1 and these values can be input to the LEGS page or PROG page 4. You may see other values depending if you are in the airway, arrival, non RNAV approach, missed approach, etc. A 0.1 RNP approach is known as RNP AR (Authorization Required) and required special certification and are usuall denoted as "RNAV RNP" on the chart. Most RNAV approaches are 0.3 and are usually called "RNAV GNSS" or "RNAV GPS" on the chart. If the LEGS page or PROG page 4 doesn't show the correct RNP just change it through the CDU scratch pad. The minimums are set usual as BARO on the PFD using the EFIS Control Panel according the procedure. Remember to add 50' to the minimums for a 3.0º slope as all RNAV approaches constant descent approach (CDAs) and perhaps more than 50' is the slope a steeper - some operators take account of steeper slopes some don't.

You are correct with regard to best climb speed (MAX RATE or Vy), this is approximately clean speed + 50, and would contribute the lowest possible trip fuel burn (all other things being equal). I am assuming that your mention of "best econ speed" is a reference to ECON speed which is the only FMC speed that uses the CRZ WIND input. ECON speed is the lowest cost determined by the operator according to their chosen cost index (CI) taking into account airframe time, fuel and possibly even schedule. Therefore "best econ" becomes a tautology and ECON speed (for all relevant phases of flight) is slower with a tailwind and faster in a headwind to best balance those vs over time compromises expressed through the CI. I got the extra information from the Bulfer FMC Users Guide. Also the FCTM has this to say on ECON speeds:

The FCOM merely says: Following on from some additional reading it seems the CRZ WIND entry is for the ToC wind for the entered CRZ ALT. Its purpose is to define the best econ speed in the climb starting with zero wind on the ground and linearly interpolating to the CRZ ALT. The LEG, RTE DATA pages are for entering forecast leg winds for predictions and smoothing against actual cruise wind. A general and unwritten rule of thumb is to enter a wind for a leg if it differs by more than 10kts or 10º of the previous entry. I fly with some guys who like to enter the average wind and leave it at that. Not my preferred method, but if there is a difference it is subtle.

Normally in state of the following: The best way to describe it is if you take the starting state as normal landing configuration then apply the following Amplified Procedures from FCOM1: After Landing Procedure Shutdown Procedure Secure Procedure Then the FCOM1 Supplementary Procedure for Electrical Power Down. That then is the normal cold and dark state. You can find all those procedures in the included Flight Crew Operations Manual Volume 1 (FCOM1) that PMDG included with the package. However, in real life, unless we were stuck somewhere overnight, the engineer completes the Supplementary Procedure for Electrical Power up before we get to the aircraft so as crew, we seldom do a C&D start up.