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Guest Captain Behrentzs

PMDG Boeing 737-800 questions

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Hi guys!I have just started to fly a ittle with the PMDG 738, which is great!!But I have some questions:1: WHERE is the TO/GA button???? I just can't find it!2: What do you use in Cost Index? I use about 80, is that too much?3: How do you calculate if you need to use Reduced CLB thrust?4: How do you calculate the V1, VR and V2??5: Where can I download SID and STARS?Thanks for your time and happy easter!---------------------------------------Kasper BehrentzsDenmarkhttp://images-032.cdn.piczo.com/p1/img/i226212866_24643.jpgwww.xflightx.co.nr[b/]

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Why don't you read the operating manual? It's not only interesting (it's pretty nice to know how it flies and how all those systems function), but also the answer to many questions. :-)1. It's the upper left screw on the MCP (glareshield).2. I've read something about 350 which would be a proper value.3. Hm, good question. Let's wait for the answers of more experienced colleagues...4. I do not, the FMC does. ;-) It's one of the FMC pre-flight initialization steps. On the takeoff data page (INIT REF) you can enter the flap setting for your takeoff, then you just have to push the RSK buttons 1 to 3 to calculate and confirm the V-speeds. But be aware, that entering the runway number after obtaining the takeoff clearance from the ATC deletes the V-speeds (the FMC will alert you bout it) so you'll have to confirm them once again.5. Navigraph nDAC3 (www.navdata.at) is a great tool for airport and enroute charts as well for SID/STARs. If you'd like to download the SID/STAR data for thr FMC, you'll find it under the same address (www.navdata.at).Happy easter to you too -- and happy flights with PMDG! =)-- Michael A. Peregudov

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Thanks for your answears!Btw are you sure the Cost Index should be set that high???Wow, strange about the TO/GA! I thought it was located somewhere on the throttle quad. Is it also located on the MCP in real world??---------------------------------------Kasper BehrentzsDenmarkhttp://images-032.cdn.piczo.com/p1/img/i226212866_24643.jpgwww.xflightx.co.nr[b/]

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The TO/GA button is actually on the throttle panel but there is a convenient hot spot on the MCP. Click on the upper left MCP mounting screw just to the left of the AT switch.I use a CI of 80 but some LCC's use much lower from 60 down to 40.After you load your fuel and then go into the FMC (make sure your weather desired is active) you setup your N1 performance. The surface temperature (density altitude correction) and winds should be there. As I recall, you do do an init-ref/index/takeoff. Enter your flaps (usually 5). When you now click the right LSKs for the V speeds they will automatically fill in saving the manual calculation. I'm not sure if its modeled but you should have your departure runway selected as the density altitude and runway length determine your V1 abort speed since the shorter the runway the lower the V1 to manage stopping on the runway.SIDs and STARS can be downloaded from the AVSIM Flight Plan Library (look for author ddowns or Dan Downs) and are also at www.planepath.com.

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>Btw are you sure the Cost Index should be set that high???Look at the page 8-21 of the Manual. But I could have misinterpreted the passage.>Wow, strange about the TO/GA! I thought it was located>somewhere on the throttle quad. Is it also located on the MCP>in real world??I think, there's a "copy" of it near the throttles too. In real planes the button is located under your thumb on the yoke.-- Michael A. Peregudov

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>Enter your flaps (usually 5).Really? I have always thought, 10 degrees is the typical setting.By the way, what does the takeoff flap setting depend on?-- Michael A. Peregudov

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>>Enter your flaps (usually 5).>Really? I have always thought, 10 degrees is the typical>setting.>>By the way, what does the takeoff flap setting depend on?Usually weight, runway length, altitude and weather conditions.For the -600 and -700 flaps 1 to 5 are the normal take off regime. Heavy a/c and short runway you'll want to use 10 or in rare occasions 15.Hope it helps,

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That's density altitude, sir :) . Couldn't resist.The standard altitude temperature is 20 degrees C. (68 F.). If the temperature goes up, the effective altitude increases. This is due to thinner air providing less lift for a given ground speed. In addition even for turbine aircraft there will be some degredation of performance.01_TAKEOFF_PERFORMANCE_737_678900_V14.pdf in your 737NG documentation has the tables for corrected runway length for wind, altitude, and temperature.In effect, the hotter it is, the longer the takeoff run to Vr. The IAS reading does inherently compensate for the speed reading of the thinner air but the TAS is higher therefore more runway is consumed. A headwind reduces the length because it reduces the groundspeed.The air is also thinner at higher altitudes so as your runway elevation increases, again more runway is needed.The end result is on a hot day at just a few thousand feet of runway elevation, you'll need a much longer runway and/or need to use a short field take-off procedure. This can require increased flaps above 5 as stated. You'll see longer runways constructed at higher elevation airports such as KDEN, Denver.Yet on top of this, you need to take in weight. Your Vr (as well as V1) will increase with weight.Again the tables give you corrections that need to be applied.The FMC does take care of some of these calculations and in the sim model just about does it all.In the real world the airplanes gross weight is calculated manually for including passengers, cargo, and take-off fuel. The pilots have access to a computer in most places that eliminates the need for charts. The weather and runway level is then entered and the results for runway length and verification of V speeds is available. Those not lucky enough to have on board laptops then use charts for calculating the landing parameters. Something like that.You've already got the PMDG Loader utility which will give you empty weight plus payload based on pax distribution and cargo, and from PMDG you can download a fuel loader utility that will help you calculate the required boarded fuel and then estimate your gross takeoff weight. In the sim FMC you just LSK the GW and it fills in automatically measuring the payload plus fuel.I've got some Boeing cockpit videos from justplanes.com where the preflight and before landing calculation procedures are illustrated as an overview.03_LANDING_PERFORMANCE_737_678900_V14.pdf02_CRUISE_PERFORMANCE_737_678900_V14.pdfare also in your documentation folder.I did not notice the FMC showing minimum runway lengths calculated but I might have missed it.More than you wanted to know. Hope it is correct :)

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I've seen Qantas in a few flight plans using CI20.RegardsRudy

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WOw Ronzie, ! Thanks bud, that was a great "lesson"!But I have a question about the V speeds: I did complete the PERF INIT page, route page, ident, N1 and so on, but the V speeds didn't show up as I pushed the buttons next to the fields. Nor could I get permission to enter the wind and the speed restrictions. In the speed restrictions field it looked like this: somenumber/FLAPS. I couldn't delete it or change it. Shouldn't I be able to do that or have I missed something?Thanks for your great help everybody!---------------------------------------Kasper BehrentzsDenmarkhttp://images-032.cdn.piczo.com/p1/img/i226212866_24643.jpgwww.xflightx.co.nr[b/]

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You may have forgotten to enter your takeoff flap setting on the page with V-speeds. Chdck whether it's entered there.-- Michael A. Peregudov

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"In real planes the button is located under your thumb on the yoke."Are you sure you're not thinking of the A/P Disconnect Button ;)Cheers.Q>

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I'm sure, that I was thinking about the right button, but I was mistaken anyway, thanks for showing this. %)I have obviously read Page 9-8 of the Operating Manuel not attentively enough: "In the actual airplane the TOGA switch is located on the _throttle_ under your thumb but that could not be modeled here".BTW, what other buttons are located on the yoke except the A/P disconnect switch? Trim buttons or some communication things, I belive?-- Michael A. Peregudov

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"Trim buttons or some communication things, I belive?"Correct. Normally two, side-by-side trim "rocker" switches and on the rear of the column, a MIC/INT (microphone/interphone) rocker switch.Cheers.Q>

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I think you also need a departure runway so V1 can be calculated. You'll note that if you change the runway the FMC will announce VSPEEDS DELETED and you have to go back to the takeoff page and recalculate them.Here's the take-off FMC procedure from Mike Ray's 737NG PC Sim book:1. POS INIT2. RTE PAGE 1 -- ORIGIN (or COROUTE to load stored plan..)3. Proceed through the RTE pages creating the route if not from a stored plan. Then ACTIVATE and EXE.4. PERF INIT5. N1 LIMIT (Usually no change.)6. TAKE-OFF (Enter flaps only for now)7. DEP (Select runway and if desired SID)8. ACT LEGS (Check route, close up discontinuities, EXE if necessary)9. Return to TAKEOFF (via INIT REF/INDEX) and LSK V-SPEEDS.Take-off V-SPEEDS should always be the last item after all other parameters bearing on performance are set.A hint for landing:Don't select your landing flaps and V-Speedsd on the APPROACH page until you are near the airport in the intial stages of approach descent. This allows the gross weight to be adjusted for current fuel load and the landing v-speeds to be calculated for the flaps schedule.

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All these things are located on the left side of the yoke (from captain's prospective), aren't they?There are also three numbers on the right side of captiain's yoke. What do they stand for? Some kind of course/heading memo?-- Michael A. Peregudov

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Just reading this topic and thought I'd put in my little bit.1. Cost Index can change quite a bit dependent on airlines, for example the airline I'm with uses a standard CI of 65 but other airlines use higher CI (or indeed lower)2. Using the takeoff performance tables is very useful and can also be used to make your simulation more realistic. The performance table can be used in 2 ways. The first is to work out your Vspeeds based on runway length, OAT and takeoff weight. The charts are usually organised as individual charts for runway length/flap setting/runway condition. Then from the chart that applies i.e: 4000ft/10/WET you read down the side to your OAT and read across to the column that is at the wind factor. This gives you a figure like 1669*/57-59-64 (for example) this would mean your Vspeeds are V1: 157 Vr: 159 V2: 164. The first figure is the MTOW (this example is for 767) The other way to use the charts is to work out your reduced thrust. This is not the same as de-rating the engines. The difference between de-rating the thrust and the reduced thrust takeoff is;* de-rate reduces the thrust from the engine ie from 26000lbs to 22000lbs* reduce thrust takeoff means that when you hit the TO/GA button and the throttle hold takes over on the takeoff it won't max the throttle therefore reducing wear on the engineReduced thrust takeoff is usually used when the runway is very long. So rather than accelerate to Vr quickly and only use half the runway length instead you accelerate slower to Vr and use more of the runway but reduce wear on engines and get better fuel burn. To calculate the reduced thrust from the charts is to again select the correct chart i.e 4000ft/5/DRY then reading up the column find the figure nearest MTOW to your calculated TOW then read across to the temp. If you put that figure into the FMC then when you takeoff you will notice that you don't hammer the engines as hard. Hope this makes sense.James

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>"There are also three numbers on the right side of captiain's>yoke. What do they stand for? Some kind of course/heading>memo?>>-- >Michael A. Peregudov"Michael,They are probably airline specific, but in the case of my recent 737NG simulator time, they generally use it to input the current "Flight number" so the PF & PNF don't forget that they are the ones being counseled by ATC for busting their assigned altitude etc.....jack

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>"In real planes the button is located under your thumb on the>yoke.">Are you sure you're not thinking of the A/P Disconnect Button>;)BTW, could you please explain to me, where exactly the TOGA button is on this picture: http://www.airliners.net/open.file/1061547/L/ ?Are they on the throttles sides (marked with "A/T disengage")?-- Michael A. Peregudov

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Yep,Those are used as simple numerical data banks for the crew. Frequencies, headings, altitudes, flight numbers and the like.It's just three simple thumbwheel counters in a row.Hope it helps,

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Michael,I memory serves me right the TO/GA buttons are the two black buttons partially shown just in front of (above picturewise) the throttle knobs.The buttons you are refering to are the buttons for disengaging the auto throttle.Hope it helps,

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Thank you, Mat!Look at the picture below, do you mean these buttons? Do they have to be pushed simultaneously on a real plane? They seem not to be very handy to push when your hand is on the throttles. Or does it only seem so because of the picture prospective?-- Michael A. Peregudovhttp://forums.avsim.net/user_files/170073.jpg

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Wish we had any panel as sharp as this picture!Andreas

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