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nicholas49

Few questions to help get me started

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HelloI've recently bought the PMDG 737NG and I love the aircraft. I can't believe I've waited so long to buy it.I wonder if some kind soul could answer a couple of questions. These relate to differences I've noticed from the standard B737 in FS2004. Please, please keep this non-technical: I am new to this.1) When I intercept the ILS (both localiser and glideslope), I notice that the APP light goes out. Is that normal? I can see that G/S and LOC appear on the flight displays. Again, this is different from the standard 737 where the APP light remains on until you de-select it. Consequently, on final approach with auto-pilot engaged, I only have the IAS/SPEED light, auto-throttle, Flight Director and COMMAND 1 lights green. Is that normal? (Incidentally, the aircraft is so much better at intercepting the localiser than the standard 737!). 2) If you use the LEVEL CHANGE function on the autopilot, where is the rate of descent indicated? For that matter, I cannot see the ROD even when in V/S other than that programmed on the MCP. Is it displayed elsewhere? What is the difference between hitting LVL CHANGE and changing altitude in V/S? Is it just the speed protection? 3) I cannot deploy the speed-brakes - the lever will not move. I can, however, arm them. Why is this? 4) There is no WINGS LEVEL button on the MCP. Is there one? 4) Is there a way to connect the A/P to the GPS navigation so that it follows a standard FS2004 Flight Plan? (The equivalent of the NAV/GPS switch on the standard 737 MCP). I am not yet at the stage of using the FMC so I just want a simple way to track a GPS course. Is this possible? 5) Is there a way to display the GPS unit on the flight deck? Sorry if that's a stupid question: I am fully aware that the navigation equipment is more sophisticated on the PMDG 737. Thanks for your help!Nick

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Welcome to the forum Nick let's get some housekeeping items out of the way first.Please take a look at the forum rules. You will note you need to sign your posts with your first and last name. http://forum.avsim.net/topic/245586-you-must-sign-your-full-real-name-to-posts-to-use-this-forum-posts-without-names-will-be-deleted/http://forum.avsim.net/topic/240151-pmdg-forum-rules-read-before-posting/Next the NG is a fairly sophisticated simulation (even for it's age). The NGX is going to be on a entirely different level. To get the most out of the product, you need to take some time and do a little homework. Start off by reading Section 00 Title and Menus manual and then the Section 10 Flight Techniques Manual. Next, take a look at Sections 5-9. This will give you a good overview of aircraft operations and systems. When your ready and have some experience in the aircraft go ahead and finish up the rest of the sections. There are also some very good tutorials available which you can find by doing a search.Ok on to your questions:

1) ... I notice that the APP light goes out. Is that normal? I can see that G/S and LOC appear on the flight displays.
Yes this is normal and operates as the real NG does. The default FS aircraft is not a very accurate simulation.
2) If you use the LEVEL CHANGE function on the autopilot, where is the rate of descent indicated? For that matter, I cannot see the ROD even when in V/S other than that programmed on the MCP. Is it displayed elsewhere? What is the difference between hitting LVL CHANGE and changing altitude in V/S? Is it just the speed protection?
This is a complex question and I am bit short on time to fully explain right now. From the manual: LVL CHG Switch: Pressing the LVL CHG switch will disengage any other active pitch mode. Level Change integrates AFDS pitch control and autothrottle thrust control to effect an altitude change.If the IAS/Mach indicator is blank: Indicator will un-blank and display the FMC target speed. If the FMC target speed is invalid, then LVL CHG will use the existing airspeed.If the IAS/Mach indicator is not blank: Command speed for the climb will remain as displayed.The Autothrottle will advance the throttles to the selected thrust for climbing, or reduces to idle if a descent is being effected.In summary, the level change mode varies the VS to maintain specific speed. VS mode maintains vertical speed regardless of airspeed. They are used for different reasons depending on the climb or decent scenario.
3) I cannot deploy the speed-brakes - the lever will not move. I can, however, arm them. Why is this?
I believe the short cut key is / and shift '/'. You can also assign and axis from your joy stick controls to them. This is what I do.
4) There is no WINGS LEVEL button on the MCP. Is there one?
The real NG AFDS doesn't have this function. If you sync your heading bug with your current heading and pressing heading select this will perform the same function.
4) Is there a way to connect the A/P to the GPS navigation so that it follows a standard FS2004 Flight Plan? (The equivalent of the NAV/GPS switch on the standard 737 MCP). I am not yet at the stage of using the FMC so I just want a simple way to track a GPS course. Is this possible?
No, there isn't a way to do this. The NG has an internal GPS in addition to even more sophisticated guidance systems. There are many flight planning tools that will export a flight plan to the PMDG format if you don't want to manually enter the flight plan into the CDU. I understand the FMC seems a bit intimidating at first, but if you take a look at the documentation I believe you will find it really isn't that difficult. To use the AFDS system effectively you need to program the FMC. The FS9 GPS isn't nearly sophisticated enough to work with the NG.
5) Is there a way to display the GPS unit on the flight deck? Sorry if that's a stupid question: I am fully aware that the navigation equipment is more sophisticated on the PMDG 737.
Similar to above there isn't an easy way to cleanly do this. I believe you can use the default key assignment to overlay the FS9 gps, but again I would encourage you to give the FMC a try.

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Before I jump into my own answers, please take note of Falcon's advice. This is no "load up on a runway and jet off" type of simulation. If that's what you're looking for, you've come to the wrong place. That being said, though, even if that's what you think you want, try some of the content that's in the manuals (or even just the tutorials) and you'll likely find that this bring a lot more to your sim experience.1) I can't remember the last time I flew the 737NG unfortunately.2) Level Change is an autopilot mode that gets there as soon as possible, either in climb or descent. Essentially, the AutoThrottle (AT) puts the throttles at the climb limit thrust (climb), or at idle (descent), and uses the aircraft's rate of climb/descent to hold a particular airspeed. Speed protection, as you mentioned, is more a byproduct of how this mode operates, not necessarily a goal of it. Essentially, FL CH is a mode where you climb/descend at a set speed. V/S is a mode you use to do so at a set V/S. The V/S will not appear on the MCP (mode control panel - where the AP buttons are), but you can see your V/S on the PFD (primary flight display) on the leftmost screen, near the altitude readout, if I recall correctly.You are no longer in the realm of "dumb" autopilots, so you might want to forget about the modes you've come across so far, other than HDG and setting the altitude you want in the ALT SEL window. You're now in the world where you use more complex modes like VNAV/LNAV (vertical/lateral navigation) and FL CH (flight level change).3) My first thought on this is that you haven't set your hydraulics, but I could be wrong.4) Few autopilots you'll come across have this mode. The closest you'll come to this is a TURBulence mode (not on the 737), or in some cases, the closest is HDG SEL(the case here).5) No. Doing so just delays the inevitable that in order to fly this thing, there's some learning to do. A shortcut, if you want one, it to take a flightplan from SimRoutes (which allows you to download in PMDG format) and bring it up in the FMC. There are instructions on how to do so in the FMC section of the manuals.6) Again, discard the notion of the default GPS. First of all, it's terrible, it's a crutch, and again, it's going to delay your learning how to properly fly.If you have any questions when you read the manuals, that's what we're here for. Good luck and let us know!

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Let me expand on the LVL CHG vs. V/S stuff a bit more - I remember this was a confusing concept way back when I started simming myself...LVL CHG (also known as "FL CH", pronounced "flitch", on the big Boeings) is what's known as a "pitch-for-speed" mode. What this means quite simply is that the pitch of the airplane is used to control the airspeed, not the engine thrust. If I hold engine thrust constant and start climbing, my airspeed is going to drop - likewise if I push the nose down and start descending, my airspeed is going to increase. There's a particular pitch setting that will exactly maintain pretty much any given airspeed that's valid within the current flight envelope.LVL CHG behaves in two different ways depending on whether a climb or a descent is commanded:Climb - the A/T commands engine thrust to increase to the current N1 limit (effectively max thrust) and the airplane noses up to whatever pitch allows it to maintain the airspeed or mach that is selected on the MCP speed window.Descent - the A/T retards engine thrust to idle and the airplane noses down to the pitch that maintains the MCP set airspeed or mach.The big important concept to realize here is that your vertical speed does not matter at all when in LVL CHG - it's actually going to vary widely depending on your altitude. All the LVL CHG mode cares about is maintaining the speed set in the MCP window through changing the airplane's pitch. In general you will notice higher rates of climb at lower altitudes and higher rates of descent at higher altitudes while using LVL CHG due to the change in air density and it's effect on the performance of the wing and engines. LVL CHG is almost always what you should use while climbing if not in VNAV - the reason becomes apparent when you consider what would happen if you tried to climb in V/S without progressively lowering the commanded vertical speed as you climbed. Due to the air density issues mentioned above, once you get high enough the plane will no longer be able to maintain the selected vertical speed without stalling if you're in V/S mode. LVL CHG is a much safer climb mode because it naturally protects against this by focusing solely on airspeed and not a rate of climb.This LVL CHG type of mode has alternate names on different airplanes - in the Airbus it's called "Open DES", in the MD-11 you can tell it's engaged when you see "IDLE CLAMP" and "PITCH" on the FMA, in the J41, Cessna Mustang, or the Embraer 135/145 it's called "IAS". You need a fairly sophisticated autopilot/flight director system to see this type of mode - most small general aviation aircraft do not have it in their autopilots, they'll only have V/S.VNAV SPD mode is essentially the exact same pitch-for-speed idea as LVL CHG except the FMC is calculating the speed, it's not set manually on the MCP. This speed is normally the "ECON" speed, which is the speed that gives you the best fuel economy based on a host of factors the FMC takes into account including your weight, thrust derate, Cost Index and so on. In order to use VNAV, you must initialize the aircraft's performance database, which effectively means completing the PERF INIT, N1 LIMIT, and TAKEOFF REF pages of the FMC with the relevant weight and balance data before you takeoff.V/S mode is most often used in descent when you want to manually make a crossing restriction (the other way is using VNAV PTH mode) - you can set the MCP altitude window to the restriction height and then roll the V/S wheel down while looking at the green arc on the ND - when that arc is over top of the waypoint, you have the proper rate of descent to make the restriction dead on.

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Please, please keep this non-technical: I am new to this.
V/S - Autopilot targets the selected V/S. Actual V/S is read next to the altitude tape. Airspeed - the autothrottle will try to stay at the selected airspeed. If you select 6000 foot/min descent, the A/T won't be able to keep you at 250knots.Level Change - A/P pitches for the selected airspeed and the A/T will be at idle for descent or climb power for a climb. Rate of descent is variable.Basic version. Have fun; you're only scratching the surface.I've never heard anyone say "Flitch." Maybe tribal.

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When the APP light goes out as you noticed you get status indications in the annunciator section of the PFD that will change according to the sequence of the approach and the action the A/P is following such as the flare command in an autoland.If you are conducting an AUTOLAND procedure be sure both ILS's are tuned to the correct frequency well before 1,000 feet AGL as soon as the G/S starts moving. You'll also notice in the upper left of the PFD where it shows the LOC ID and frequency tuned that on GS capture it will change color. At 1,000 feet AGL arm the second A/P sensor system, that is the CMD button on the MCP so that both are lit. Above 1,000 feet AGL this action will just switch between them. (If both nav radios are not tuned to the same frequency you'll get a warning in the FMC scratchpad when you engage both. In addition in a few cases you may get a NAV DISCREP warning in the FMC. If the installed airport scenery uses a different LOC/ILS frequency than in the FMC database, you might get this. Use the ILS frequency built in to the scenery you are using. You need to know this preflight to tune your nav radios. I'm not sure if the FS map updates that info with scenery add-ons but you can if you wish for FS9 use AFCAD 221 to look at the top layer of the airport afd files and view under List/NAVAIDS the frequencies of each. I do not recommend saving any files with AFCAD, another topic.)

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Flitch, huh? Hmmmm. Alaska, Korean, and I don't think NWA use(d) that term. "Maybe Boeing should come up with an official pronunciation guide. Is it Vor-"Lock" or Vor-"Loke"? biggrin.gif

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