By lex, on March 20th, 2011
With a score of 98%. Which is exactly the score I got 10 years ago, back before the world got in the way. Which says something, I think, about consistency.
The good news is that I actually understand weight and balance equations now, instead of blindly memorizing and applying formulas. Thus, ΔCG in inches = (Distance x Weight) / Total Weight, and Weight to be added = (Old Weight x CG Change) / Distance from weight station to new CG. And oh yeah, Weight x Arm = Moment, like it’s even worth mentioning. It’s of course much easier to to perform these calculations in moment indexes by dividing weights by 1000 on long axes.
Which, everyone knows that.
And! I have recently become again aware that Nautical Air Miles/1000 pounds (for specific range calculations) = TAS x 1000/Fuel Flow.
Sadly, I did not recollect that when performing payload calculations that, should the estimated fuel burn en route + takeoff weight exceed allowable takeoff weight – forcing you to of course choose max takeoff weight as the smaller of the two indices – that you had to first subtract zero fuel weight from max takeoff weight before subtracting basic operating weight. Which everyone will agree should have been blindingly obvious, and of course it is in retrospect.
Which leads me to one question, and another observation: 1) I wonder if there’s an iPad app for that, since I’m burning for an authentic reason to purchase one, and 2) I couldn’t help but notice that we seem to be at war again.
It’s funny what can happen when you take your eye off the ball, or head to Brazil, etc.