Gents,

 

A couple rules about airplane performance numbers:

 

1) Marketers lie.

2) Liars market.

3) Never believe anything you hear a broker say.

4) Discount anything the sales guy says while he is communicating in any manner.

 

Go by the engineering data, if you can get your hands on it.

sounds like on an egyptian bazar ;-)

I guess this post has cleared up a lot of information for me

Thanks lots everyone.

Absolutely, at minimum you must have seats for the pilots to rest in. some have more if they carry animals and support staff need to sit in seats. - David Lee

 

Not in my world. :smile: 

 

blaustern

Even the USAF/Lockheed C-5A has a passenger compartment above the cargo deck. It is located aft of the wing main spar carry through box.  Access via a ladder.  No windows but the ride is very nice, much better than the web seating in a C-130.

Speaking of this weight stuff, I'll be eager to get my hands on an accurate PFPX profile for the different types of of 744 and the 748 based on what pmdg has for pax, weight, etc... Must have IMO.

Speaking of this weight stuff, I'll be eager to get my hands on an accurate PFPX profile for the different types of of 744 and the 748 based on what pmdg has for pax, weight, etc... Must have IMO.

I am using these files by FlyPrecisely - http://forum.aerosoft.com/index.php?/files/file/3514-pfpx-boeing-747-400-performance-profiles-pack/. They maybe right or wrong but they get me to where I am going. Any oddities in fuel burn, cruise altitudes, or step climbs I just blame it on PFPX.

 

 

I am using these files by FlyPrecisely - http://forum.aerosof...-profiles-pack/. They maybe right or wrong but they get me to where I am going. Any oddities in fuel burn, cruise altitudes, or step climbs I just blame it on PFPX.

 

I suppose we will have to wait until we get the final product released though to see if they are accurate or how accurate they are.

guys,

 

the profile if fed properly is not the one to blame ....

 

Phil

 

ps i have a wonderful 748f profile that i cant wait to test ....

Speaking of this weight stuff, I'll be eager to get my hands on an accurate PFPX profile for the different types of of 744 and the 748 based on what pmdg has for pax, weight, etc... Must have IMO.

 

I am using these files by FlyPrecisely - http://forum.aerosoft.com/index.php?/files/file/3514-pfpx-boeing-747-400-performance-profiles-pack/. They maybe right or wrong but they get me to where I am going. Any oddities in fuel burn, cruise altitudes, or step climbs I just blame it on PFPX.

the profile if fed properly is not the one to blame ....

So who or what is to blame for the incorrect initial cruse altitudes and step climbs that are way to soon? I just go with what the FMC indicates in terms of initial cruise altitude and when to do a step climb

So who or what is to blame for the incorrect initial cruse altitudes and step climbs that are way to soon? I just go with what the FMC indicates in terms of initial cruise altitude and when to do a step climb

Min/max altitudes on the airways probably.

Orn

So who or what is to blame for the incorrect initial cruse altitudes and step climbs that are way to soon? I just go with what the FMC indicates in terms of initial cruise altitude and when to do a step climb

Could also be avoiding strong headwind or profiting from strong tailwinds as much as possible. Not sure if PFPX takes this into account.

Min/max altitudes on the airways probably

Where does this information come from?

Where does this information come from?

The data provider.

Orn Could also be avoiding strong headwind or profiting from strong tailwinds as much as possible. Not sure if PFPX takes this into account.

I am not writing about routes generated by PFPX. These routes are a copy/paste from FlightAware to PFPX.

The data provider.

Kyle

Consider this KLAX-PANC route in the 744F. PFPX shows an initial altitude of FL360 when the airplanes optimum altitude was 33500 and maximum altitude was 36700. Airplanes' FMC VNAV page 2 works out to an initial altitude of FL340 with a step climb to FL360 just past the KANUA waypoint which is 1100 miles away. PFPX shows a step climb to FL380 just past OAK. The 744F never climbs to FL380. In fact the PFPX step climb to FL380 is above the maximum altitude of the plane. PFPX is consistently optimistic is there predictions of initial altitude and when to perform a step climb.

 

The PFPX flightplan is at - https://www.dropbox.com/s/g7aoobu4vgsp1he/CLX55%20KLAX-PANC%20(20%20Jan%202017)%20%231.txt?dl=0.

 

I believe PFPX's initial altitudes and step climbs are tied to maximum altitude rather than optimum altitude or if PFPX consider optimum altitude in step climbs it is given little weight in comparison to maximum altitude.