Hello,

 

I am PFPX Beta tester and support agent, TOPCAT forum administrator and moderator.

 

I see PMDG passenger weight is hard coded to 80 kg (~ 176 lbs) which not correspond to real life weight as it is varying following type of flight.

So I can set the ZFW according to TOPCAT but CG is wrong according with this difference.

 

Could you correct this or help me to be nearest real settings ?

 

Best regards

Pierre Chassang

 

 

I see PMDG passenger weight is hard coded to 80 kg (~ 176 lbs) which not correspond to real life weight as it is varying following type of flight.

 

Funny thing about that is that it doesn't correspond to the real life weight of a lot of people.  It's an assumption - an average.  Most people on the plane weigh nothing near 80kg - both high and low.  It's not like everyone in back is 80kg exactly.

 

Have a look here:

http://forum.avsim.net/topic/443404-pfpx-weight-estimates-vs-actual/

 

 

 

Could you correct this or help me to be nearest real settings ?

 

Change the passenger weight assumption in TOPCAT and PFPX.

Even if you were to set the pax weight to 80kg in TOPCAT, the CG would still differ, I think.

Hi,

 

The wrong weights are from PMDG, not from neither PFPX or TOPCAT.

So It should be PMDG who have to modify / correct their data.

 

Best regards

Pierre

That may be so... but:

 

1. I do believe 80kgs is what some airlines use to estimate pax weights. Kyle has a really nice video explaining all this stuff. It's this one,i believe.

2. Wouldn't it be easier to change those weights in your planning than to wait until PMDG decides to give you an option to change that yourself? They have bigger fish to fry right now.

3. Not even real world airline pilots get an 100% accurate load sheet.

4. Like i said before, even with complete agreement regarding weights between NGX and TOPCAT/PFPX, you will STILL get the wrong CG.

 

 

The wrong weights are from PMDG, not from neither PFPX or TOPCAT.

 

To be bluntly honest, none of the weights are "right."  People all weigh different amounts, so 170, 180, 190, and 200 are all going to give you a wrong weight.

 

In the end, weight is weight.  Plan using PFPX and TOPCAT, and just enter ZFW into the CDU PAYLOAD page to set your weight.  If you're going to get specific about the CG, adjust the balance of the weight with cargo.

But it seems through doing the math that the NGX FMC is assuming 175lbs per passenger. Is that what everyone else sees?

 

Dave

Read what Kyle writes! Do NOT enter number of passengers in the CDU. instead enter the ZFW you get from whatever flight planning software you use. That way you overcome two problems: 1st you can choose what ever standard PAX weight you would like. 2nd you are not restricted to the PMDG seating layouts such as not beeing able to seat more that 174 PAX in the 800.

I have also seen 75kg per passenger being used. What's correct can differ from company to company. While we are at it, how about baggage allowance ?

 

In all seriousness Kyle & Lasse have it nailed though.

Airlines do use 80 Kg's as a standard passenger weight. I was in flight planning and performance/operations for many years. Unless you weigh every individual pax, never going to be accurate no matter what weight you use. This weight also includes carry on baggage and with some pax, this makes 80 kg's even a little conservative..........