Simviation Forums

This program is really starting to frustrate me. It's not accurate. Jet A weighs 6.84 Lbs per US gallon. The game says 6.7, but it actually calculates 6.6992. It's making it very difficult to plan fuel usage and weight for payloads. On top of that the aircraft I'm using has a fuel planner that is messed up too because guy that wrote it doesn't have accurate weights. He used CV440 weights and fuel usage on a CV580. GHHaaaaaaaa. Attention to detail folks. Sorry, just had to rant a little more. I guess that's what you get when you let computer programmers create aircraft. :-/ Having spent almost 2 decades working in various aspects in the aviation industry, I guess I expect a little too much from these computer guys. I actually expected some realistic aircraft and a realistic sim. (MS Flight Simulator 2004:Century of Flight "As Real As It Gets") PAH!

This program is really starting to frustrate me. It's not accurate. Jet A weighs 6.84 Lbs per US gallon. The game* says 6.7, but it actually calculates 6.6992. It's making it very difficult to plan fuel usage and weight for payloads. On top of that the aircraft I'm using has a fuel planner that is messed up too because guy that wrote it doesn't have accurate weights. He used CV440 weights and fuel usage on a CV580. GHHaaaaaaaa. Attention to detail folks. Sorry, just had to rant a little more. I guess that's what you get when you let computer programmers create aircraft. :-/ Having spent almost 2 decades working in various aspects in the aviation industry, I guess I expect a little too much from these computer guys. I actually expected some realistic aircraft and a realistic sim. (MS Flight Simulator 2004:Century of Flight "As Real As It Gets") PAH!

*...that is the magic word!......!

Paul...G-BPLF...FS 2004...FS Navigator...and a Game Computer... ...!

Are the values of liquids weight, temperature specific? Such as water?

Fuel is always temp specific as well as elevation specific. For a general weight it is measured at ~68deg F at sea level. I was more frustrated that the program says 6.7 but really measures at 6.6992. It's not a big deal if you have 100 gal or less, but when dealing with 1000-10000 gal, that really changes the weight and balance. If I have 1730 gallons of Jet A weighing at 11591 lbs (6.7*) but the program really thinks I have 11589, sure that's only 3 pounds, but it's actually a big deal when you're trying to calculate weight and balance or fuel burn rate. Especially if you're trying to keep your fuel load down so you can increase cargo load.

I guess I'm just a stickler for minute detail. When in the service as a structures mechanic we measured our metal down to the .01" with +/-.01" for general structures and the machinists were at .001" +/- .001". Same with degrees of arc. It's amazing how far off something can get over large numbers when you're off by just a little bit.

Well, I've got the fuel planner adjusted to an acceptable error limit. Though I can't stand discrepancies no matter how minute they are. For some reason the guy has added in an unknown percentage to hold back for fuel capacity that equates to about 10%. It's maddening to look at a calculation that says "fuel capacity" (meaning usable fuel) only to know that it's about 1000 pounds less than you know what is in there. I wish I knew how to build all the air files and such. "Strive for perfection, or else."

If I have 1730 gallons of Jet A weighing at 11591 lbs (6.7*) but the program really thinks I have 11589, sure that's only 3 pounds

Tell the pilot to leave his wallet at home... that will lose at least 4 lbs... problem solved.

...or throw a fatty off the plane.

Really? 3 Pounds? You do realize that's only about 4 seconds worth of fuel on most airliners...

To be honest, as long as that fuel weight starts with a "6" or a "7", I don't give a hoot. I'm willing to bet that the inadequacies in the VNAV calculations will offset the flight much, much more than 3 lb.s worth of JP-4 ever can.

Plus, you should be landing with an hour worth of reserves anyways, so do you really notice the extra little fuel that will be spent hauling those 3 pounds around?

...or throw a fatty off the plane.

Touche....M'sieur Pussycat  .

Are the values of liquids weight, temperature specific? Such as water?

Everything is

The mass of a given amount of something won't change, unless you add or take something from it, but volume will by temperature

What about the weight of the pilot's head?  It usually gets larger in proportion to the aircraft.  As one local jet owner said of our FBO owner/pilot, "we can't buy this plane, his head won't fit through the door!"

Really? 3 Pounds? You do realize that's only about 4 seconds worth of fuel on most airliners...

An airliner which will probably be filled up rounded to the nearest 1000lb/1000kg (depending on measure used).

Really? 3 Pounds? You do realize that's only about 4 seconds worth of fuel on most airliners...

An airliner which will probably be filled up rounded to the nearest 1000lb/1000kg (depending on measure used).

At our airport, it is usually to the nearest hundred pounds.  The airline will typically request 2300 or 2500 pounds for flights.  Our FBO does however have a 30 gallon minimum in order to hook their truck to the aircraft, so if they land with 2250 pounds and need 2300 for the next leg, they get a lot more.