February 2, 20188 yr Hi, This may be a very quick and simple question for you all. I went digging with regards to weights so I could set up SimBrief correctly. I found the Empty Weight for the 777 to be 344,224 pounds (From the Aircraft.cfg, couldn't find it in the FCOM.) I've never been able to get my ZFW to align with my VAs estimate, and after finding this, I've realised why. Because my empty weight is heavier than their ZFW. I looked here for a reference: http://www.boeing.com/assets/pdf/commercial/airports/acaps/777_2lr3er.pdf It states that the empty weight for a Boeing 777-200LR is 320,000. Now this weight would allow me to use the suggested ZFW for my VAs flights and makes sense, so I'm starting to think the Empty Weight for the 777 is incorrect. So my question is, is the Empty Weight in the .cfg correct and if so, why is it so much heavier than Boeing's documented numbers? Thanks, Mark Gibbons.
February 2, 20188 yr Commercial Member 51 minutes ago, Mark.Gibbons7 said: Hi, This may be a very quick and simple question for you all. I went digging with regards to weights so I could set up SimBrief correctly. I found the Empty Weight for the 777 to be 344,224 pounds (From the Aircraft.cfg, couldn't find it in the FCOM.) I've never been able to get my ZFW to align with my VAs estimate, and after finding this, I've realised why. Because my empty weight is heavier than their ZFW. I looked here for a reference: http://www.boeing.com/assets/pdf/commercial/airports/acaps/777_2lr3er.pdf It states that the empty weight for a Boeing 777-200LR is 320,000. Now this weight would allow me to use the suggested ZFW for my VAs flights and makes sense, so I'm starting to think the Empty Weight for the 777 is incorrect. So my question is, is the Empty Weight in the .cfg correct and if so, why is it so much heavier than Boeing's documented numbers? Thanks, Mark Gibbons. Mark, The empty weight is different per airliner as it includes also the cabin fittings, extra equipment etc. If you see on the document you sent this is mentioned as well. We simulate a plane with Empty weight of 344224 pounds or 156.1tones. Chris Makris PLEASE NOTE PMDG HAS DEPARTED AVSIM You can find us at http://forum.pmdg.com
February 2, 20188 yr Just to add to Chris' post -- the reason you won't find the empty weight in the FCOM is because it is unique to every airframe. Each specific aircraft in a fleet has a separate document detailing its specific empty weight and CG datum, taking in to account the equipment fitted to that particular airframe. Periodically the airframes are re-weighed and the OEWs updated. So this is one of those things which cannot be correct or incorrect - it just is. Saying that, your VA must be using exceptionally light loads if your ZFW is consistently less than the OEW of the PMDG model -- are you sure you've not got a lbs/kgs issue going on? Simon Kelsey
February 2, 20188 yr Author Hi gents, Perfect, thanks for the response. Just wanted to make sure it was correct, of course I can work with it and ignore the CFP as it's only guidance anyway. 8 minutes ago, skelsey said: Saying that, your VA must be using exceptionally light loads if your ZFW is consistently less than the OEW of the PMDG model -- are you sure you've not got a lbs/kgs issue going on? Yes, double checked to make sure. Perhaps they're using the rock bottom 320,000, I don't see how else they could be doing it. Thanks for your help, Mark.
February 2, 20188 yr 9 hours ago, Olympic260 said: The empty weight is different per airliner as it includes also the cabin fittings, extra equipment etc. If you see on the document you sent this is mentioned as well. We simulate a plane with Empty weight of 344224 pounds or 156.1tones. I'm surprised, with all the emphasis on reducing weight and recent use of composite materials, that an extra 24,000 lbs would be acceptable to any airline. I am curious to know, what adds so much extra weight? Thanks
February 3, 20188 yr Commercial Member 14 hours ago, Mike777 said: I'm surprised, with all the emphasis on reducing weight and recent use of composite materials, that an extra 24,000 lbs would be acceptable to any airline. I am curious to know, what adds so much extra weight? Thanks Mike, Cabin fttings, ie first class suites etc, galleys, lavatories, extra equipment like satphone, on board internet etc etc etc Chris Makris PLEASE NOTE PMDG HAS DEPARTED AVSIM You can find us at http://forum.pmdg.com
February 3, 20188 yr 6 minutes ago, Olympic260 said: Mike, Cabin fttings, ie first class suites etc, galleys, lavatories, extra equipment like satphone, on board internet etc etc etc Thanks. I would have guessed that galleys & lavatories would be included in the base empty weight. But not the elaborate furnishings in first class or satphone equipment. Mike
February 3, 20188 yr 42 minutes ago, Mike777 said: Thanks. I would have guessed that galleys & lavatories would be included in the base empty weight. But not the elaborate furnishings in first class or satphone equipment. Mike I‘m quite sure the seats on a KLM 738 have a different weight than te seats on a Ryanair 738. then the first class suite on an Emirates 777 is pretty different to the seating on an AAL 777... and so on. Boeing gives a factory native weight but that is absolutely empty, nothing in there... edit: I just woke up and didn‘t read your post correctly that‘s actually what you said... ,
February 3, 20188 yr Also worth noting that Boeing's figures on their website are, I would presume, essentially marketing... "Our 777 is lighter than ever before - 320,000 lb. (Of course, that's rounded down, with virtually no useful equipment at all on board and the lightest and most basic versions of everything but you'll find that out when you buy it...)" Simon Kelsey
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