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Old 21st Apr 2016, 19:29
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Channel 2
 
Join Date: Mar 2016
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Originally Posted by KenV
Channel 2 has set himself up as an expert on area rule. Can this "expert" state how area rule is implemented on the F-22? Or will he continue to ignore the question?
I do not claim to be an expert on area ruling. But these two (2) concepts are fairly straight-forward.

1) The F-22 is 62-foot long. The F-35A is 50.5-foot long. The F-22 is 11.5 foot longer. The F-22 has a 44.5-foot wide wing span. The F-35C has a 43-foot wide wing span. So which aircraft most closely conforms to the Sears-Haack body? The answer mostly explains why the F-35C struggles to accelerate in the transonic region. As for the F-35A, its wingspan is 35-foot. But the Sears--Haack equation utilizes radius, not diameter so the 9.5-foot difference is actually 4.75-foot. The F-22 is 11.5 foot longer with only a 4.75-foot R differential.

And here is the devastating part. Negate the wings on both aircraft and redo the equation. One of them ends up looking almost identical to a Greyhound bus. Guess which one?

2) Internal volume is a rusty double-edged sword when it comes to area ruling. Remember how the F-35 fanboys love to brag about, "all that enormous internal volume?" Well...as it turns out...it's impossible to area rule a 50.5-foot long aircraft with that kind of volume.

Here is the bottom line. The F-35A and C both carry the same internal cross sectional volume of the F-35B. The 'B' needed a lift fan, but from the cross section distribution point of view, it was a tragic mistake for the F-35A and C to have space for a ghost fan that is nearly as big as an Embraer 190 engine right behind the cockpit.

All My Best, Gents!
Channel 2 is offline