Hello Guys,

 

I need some help here, i'm planning a flight from brisbane (YBBN) to Seychelles (FSIA), the trip can't be done with ETOPS 180, only with 207, and my question is about the ring diameters i should put on the FIX page.

 

Another question: The CI (64 by PFPX default) seems not logical to this flight. So i can't adjust the CI, only the MACH, for example MACH 0.86 which CI corresponds ?

 

Thanks

 

 

Just type a number in the CI . Dont use the scroll down

 

I still have a lot to learn about ETOPS. Hopefully we can find some videos ?

 

 

Remember to look at the Tutorial 1 also

 

 

Michael

yep, search for kyle tutorials in youtube. PFPX tutorial 1 and 2

If you are using PFPX, it should give you a maximum diversion distance. Divide that number by 3.45 (207/60) if youre using ETOPS 207 and thats gonna give you the range you should use in the fix page.

yep, search for kyle tutorials in youtube. PFPX tutorial 1 and 2

http://forum.aerosoft.com/index.php?/topic/73453-pfpx-etops-pmdg777-a-short-guide-p1/

http://forum.aerosoft.com/index.php?/topic/73486-pfpx-etops-pmdg777-part-2-flightdeck/

 

 hope the above helps

Also remember that you don't necessarily need to stick to the most efficient route if ETOPS is your limitation.  Say you're flying for an airline that doesn't have 207 minute ETOPS - you might have to route a little bit further North to stay within 180 minutes of an ETOPS alternate in order to operate a YBBN-FSIA leg.

70nm = 10 minutes flying time. I use 420nm to represent 60 minutes flying time in the FIX page. Max ETOPS diversion distance for 207 minutes is 1414nm. 

 

Going Mach.86 is extremely rare in the real world - very close to MMO (which is .89). I could only see sense doing that kind of speed if you were in smooth air and either in a medical emergency or making up some lost time. I don't think I've ever seen M.85 for a constant speed cruise - mainly because airlines would rather keep her between .82>.84 and save the fuel. A good practice to start doing, is checking enroute weather first. That way you can see what the weather is doing - no point trying to do .85 in moderate turbulence, since you should be coming back to .82 to provide a safer margin. I had to go all the way back to .80 over Denver the other day due to moderate turbulence. I use .82/.83 with a tailwind and .84 with a headwind on constant speed cruises - on NAT's for example. 

 

You can change the CI every flight in PFPX. Just click the box and type your number in and it'll change. 

For example Air France use CI 120 on B772 and 180 on 77W & 77F. the Mach is around 0.837

How come then if i put CI 80 i have mach 0.84?

How come then if i put CI 80 i have mach 0.84?

 

CI takes into account several different factors (and has a variable result based upon them).  If CI translated directly to Mach, we wouldn't need to use CIs and would instead just insert a cruise mach into the FMC.   :wink:

How come then if i put CI 80 i have mach 0.84?

CI is not a fixed mach speed!

 

CI for instance will increase the Mach number in strong headwinds and decrease it in strong tailwinds.

(if you enter forcast winds into the legs/data page you will see accurate an varying speed predictions on the legs page. If you dont enter forcast winds then the FMC will still vary actual target speed (on your PFD) according to actual winds but the legs page will not reflect this)

 

CI also varies your Mach depending on how high you are flying (fly below optimum altitude and you get something like M.80 - M.82. When you climb to optimum altitude again you will get something like M.83 to M.85 depending on CI).

(those speeds are just examples for common CI values. if you enter CI=0 or CI=9999 you are going to get different Mach number ofcourse)

 

A higher cost index means that you are telling the FMC that for this flight, time based costs are of higher priority.

(for instance to prevent crew to fly into overtime, or to reduce time based maintenance costs or to make up for a delay (delays cost money too!))

 

A lower CI means you are telling the FMC that for this flight, time base costs are of lesser importance due to for example high fuel costs in comparison to crew and maintenance costs.

VEry interesting reading ROB... Thanks