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I'm studying to become a pilot and stumbled upon the Raptor Aircraft a while ago.

In one of our subjects we briefly discussed the concept of the area rule but did not get into much detail since our teacher told us that for subsonic airplanes it is not very relevant, especially not for slow flying piston aircraft.

But the designer of the Raptor Aircraft gets into a lot of detail why the Raptor is shaped like it is and what performance benefits it provides.

To me the charts provided on this site make a lot of sense and it seems plausible that there is a drag reduction of 15%.

I get that for airliners 'ease of build' is a major factor and therefore the cabin is a cylinder (reasons described in this question). (Sidenote: as far as I know the A380 has a double bubble design.)

Here comes the question: can someone provide a chart of the cross sectional area like this one for the A320 or another jet airliner?

What interests me is how much performance gain/fuel savings/drag reduction could be achieved if one were to optimise the cross sectional area of an airliner.

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  • $\begingroup$ They do keep the area rule in mind when designing transsonic airliners. Although you don't much see anti-shock bodies on new airliners. $\endgroup$ – TomMcW Apr 12 '18 at 17:19
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There seem to be plenty of drawings available with A320 dimesions.

https://www.google.com/search?q=a320+cross+sectional+area&tbm=isch&source=iu&ictx=1&fir=xqsB2UJmwNJExM%253A%252CZ-goV0XUZnxtFM%252C_&usg=__VvKRKRr0Rto02mNZc1OcLUazPPY%3D&sa=X&ved=0ahUKEwjUpvCm54XbAhWBPZoKHXyTC9gQ9QEILTAB#imgdii=3XaIv6qHo-5doM:&imgrc=IdDuWmIhnnky0M: I'd suggest pulling the data from several as needed and model the A320 so you can try changes in SolidWorks as the Raptor design team did for their video.

Maybe SolidWorks has a student license you can download & use.

https://www.solidworks.com/

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I considered making this a comment as it deals with the premise of your question, but not the actual question. I put it here anyway.

Raptor is nothing like an airliner, which is the stated object of your question. I would be cautious about any comparisons of a paper airplane against one that actually flies, and about extrapolating any aerodynamic principle from one flight regime to another.

Area ruling affects wave drag, which simply is not present on this optimistically rated 230kt prop powered aircraft. The aircraft would have to be going twice its planned speed for a swept wing to begin to delay drag rise onset, the reason commercial airliners use it.

The Raptor's wing is swept in order to place its vertical control surfaces as far aft as possible since it does not have a conventional tail. Calling it area ruling is wishful engineering at best, camouflage at worst. At low speeds a swept wing has many handling problems and a straight wing (as the SR22 has) is far superior. How many low speed aircraft do you see with swept wings?

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