A Few questions in regards to Real Life Ops

[NGXfanatic 85]

Hello, I am attempting to find out more info on the real life procedures used in the 747-400 to help me achieve maximum realism with the simulation. I had a few questions/observations and I'm hoping some real life or experienced simmers could chime in .1. Cost Index. I use 40 CI for all my flights, but I have read that sometimes during the takeoff phase/arrival in the terminal area, CI 100 or more is used to adhere to ATC instructions for speed or altitude restrictions to ease traffic flow. So what I do is plan the fuel load for the entire flight with CI 40, but I use CI 100 on the ground until I'm at cruise (or after the accel to climb speed above 10,000 ft). Does this process sound reasonable?2. Step climbs at cruise altitude, I use 500 fps and V/S for passenger comfort, vs. punching in the new step climb altitude and having the autopilot automatically use to VNAV manage the climb. With VNAV climb the aircraft would most likely climb above 500fps, using more engine power/fuel, and likewise the high rate of climb could be a problem for passengers settled for the cruise. In my real life travels, I have noticed that the step climbs were very smooth, so I figured that they were using 500 fps as well.3. Packs off takeoffs. I use fs2crew and have the copilot shut off packs 2 and 3 during all takeoffs. I read somewhere that some operators have all packs off when the OAT is 30C or above. At what point during the climbout are the packs restored? After all flaps are retracted, or after the transition from takeoff to climb thrust?Those are a few I could think off at the moment. I'd appreciate any comments. Happy landings!

[Ralgh 43]

On cost index I fly the 737 for American and the flight planning computer comes up with a different number for every flight. I commonly see from 4 to into the low 100s. One time they actually gave us 500 but in reality anything above the high 100s is going to give you the exact same numbers. Both airlines I have worked for didn't want us to use V/S to climb because it can cause a stall if you don't pay attention which has happened. VNAV is not that severe and climbing using it at American is standard procedure as I suspect it is at most airlines. Level change/Flight Level Change will give you basically the same results as VNAV except at the change over from indicated airspeed to Mach. As for question 3 I don't know. We don't normally do any packs off takeoffs. Wo do engine bleed off takeoffs when we are heavy from short runways but the packs are being supplied from the APU bleed in that situation.

[NGXfanatic 85]

I appreciate your insight Tom, thanks very much! I'm looking forward to the PMDG NGX, and my first flight will be replicating a real life vacation from KPHL to KMIA, American 737-800W. The vacation flight was March 2010, and a few days before the flight I flew the PMDG FS2004 737 with the same route (from FlightAware) just to see what I may expect to see in RL. Low and behold, during the vacation flight I flew the exact same route as in FS2004, even the sids/stars were the same! I love the level of accuracy that flight sim provides in relation to reality, and I am accumulating as much knowledge as possible by research real ops from the web as it pertains to the NG........input from yourself and other pilots helps us simmers greatly.

[yos233 1]

Keep in mind that the CI in the PMDG version is reduced by a factor of 10. So the CI of 40 is 400 in RL. The CI of 500 is 50 in FSX.

[scandinavian13 5,192]

To be honest, all of these questions are primarily company SOP-driven. Each company has a different metric for determining what to use and why, and each thinks theirs will give them the advantage (cost or safety) over the other.

2. Step climbs at cruise altitude, I use 500 fps and V/S for passenger comfort, vs. punching in the new step climb altitude and having the autopilot automatically use to VNAV manage the climb. With VNAV climb the aircraft would most likely climb above 500fps, using more engine power/fuel, and likewise the high rate of climb could be a problem for passengers settled for the cruise. In my real life travels, I have noticed that the step climbs were very smooth, so I figured that they were using 500 fps as well.

If you ride a bike with gears, try this:Put your bike in the most "economical" gear for a flat land speed (mostly somewhere in the middle), and then run up a hill in that same gear. You're likely going to wear yourself out and use more energy in the long run. Next time, drop a few gears and power up the hill. You're likely to feel better about the ascent after the second method.If you don't like the above example, I'll rephrase it:Take that same bike up a long, slow, everlasting uphill climb. Next time, instead of taking the route with the long climb, take a really high grade hill and power up it. You're likely to feel better after the second option.In both cases, getting the climb out of the way will save more energy in the long run, especially when you're spending more than a few hours at each altitude. Slow isn't always the most economical.My point is that in the 747, you're better off just getting up there, instead of dragging it out. Furthermore, on the point of passenger comfort, people only feel accelerative forces, not actual velocity, so as long as your changes in pitch are not too sudden, people won't really notice the difference between 500FPM and 2000 (in a pressurized aircraft). Beyond that, you might also irritate ATC in the process of using a slow climb (they generally assume a jet will use something similar to FL CH to move between altitudes). If you are cleared to climb to your new altitude, you need to cross an altitude with traffic going the opposite direction. Minimize the risk and clear that opposing altitude as quickly as possible: use FL CH.

[Paul_Smith 92]

Hello, I am attempting to find out more info on the real life procedures used in the 747-400 to help me achieve maximum realism with the simulation. I had a few questions/observations and I'm hoping some real life or experienced simmers could chime in .1. Cost Index. I use 40 CI for all my flights, but I have read that sometimes during the takeoff phase/arrival in the terminal area, CI 100 or more is used to adhere to ATC instructions for speed or altitude restrictions to ease traffic flow. So what I do is plan the fuel load for the entire flight with CI 40, but I use CI 100 on the ground until I'm at cruise (or after the accel to climb speed above 10,000 ft). Does this process sound reasonable?2. Step climbs at cruise altitude, I use 500 fps and V/S for passenger comfort, vs. punching in the new step climb altitude and having the autopilot automatically use to VNAV manage the climb. With VNAV climb the aircraft would most likely climb above 500fps, using more engine power/fuel, and likewise the high rate of climb could be a problem for passengers settled for the cruise. In my real life travels, I have noticed that the step climbs were very smooth, so I figured that they were using 500 fps as well.3. Packs off takeoffs. I use fs2crew and have the copilot shut off packs 2 and 3 during all takeoffs. I read somewhere that some operators have all packs off when the OAT is 30C or above. At what point during the climbout are the packs restored? After all flaps are retracted, or after the transition from takeoff to climb thrust?Those are a few I could think off at the moment. I'd appreciate any comments. Happy landings!

In RL, trying to second guess the automatics rarely gives good results. 1) If your CI is 40, use a CI of 40 unless you have a very good reason to use a different CI. 2) Your AP has a button called FL CH which is used to change flight level. There are situations where you can do a better job of it then it can, but you have to know in advance exactly what it would do and why you doing something different is better. 3) Your 'After takeoff' check list indicates when to re-engage packs. You need to have a very good reason to diviate from that check list. One that you are willing to stand in front of an air crash investigation and justify.