# Area of Airfoil cross-section

• Alec Trujillo
In summary, the conversation revolves around determining the radius of gyration, section modulus, and Q values at the neutral axis for a symmetric wing cross section. The challenge lies in finding the area of the cross section, which is given as the integral of (f(x)-g(x)) from 0-1. The conversation also touches upon finding the curve using boundary conditions and suggests using the mean aerodynamic chord (MAC) for future aerodynamic calculations. The adoption of boat building terms and techniques in aircraft engineering is also mentioned.

#### Alec Trujillo

New poster has been reminded to post schoolwork in the Homework Help forums and use the Template
Not really sure if this thread belongs here but I am supposed to figure out the radius of gyration, section modulus, and Q values at the neutral axis for this symmetric wing cross section. The only problem is that I am not even really sure how to find the area of the cross section. i know that it'll be ∫(f(x)-g(x)) dx from 0-1 (pretty much the only hint that we are given is that the cross section can "fit perfectly in a 1in x 1in box) but how i even find f(x) and g(x) is beyond me.

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Poster has been reminded to watch for misplaced homework threads, and not to do the student's homework for them.
There is a high chance for my answer to be wrong.If its right, by solving the equatuon with the boundary condition will give you the curve(refer the image).
If X axis in the diagram is your neutral axis then it is better to find x as a function of y by using the same boundary condition.(To calculate 2nd moment of area about the x axis).

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Alec, for future aerodynamic calculations consider determining the mean aerodynamic chord (MAC) of the wing section under study.
https://en.wikipedia.org/wiki/Chord_(aeronautics)

Before digital computers became common, aircraft engineers adopted many terms and techniques from boat building including chords.

--Norm

## What is the area of an airfoil cross-section?

The area of an airfoil cross-section is the total surface area of the airfoil, including both the upper and lower surfaces. It is usually measured in square meters or square inches.

## How is the area of an airfoil cross-section calculated?

The area of an airfoil cross-section can be calculated using the formula A = 1/2 * c * (t1 + t2), where A is the area, c is the chord length, and t1 and t2 are the thickness of the upper and lower surfaces respectively.

## What is the significance of the area of an airfoil cross-section?

The area of an airfoil cross-section is an important factor in determining the lift and drag characteristics of an airfoil. A larger area generally results in more lift, but also more drag.

## How does the area of an airfoil cross-section affect flight performance?

The area of an airfoil cross-section directly affects the amount of lift and drag produced by the airfoil. A larger area can provide more lift, but also creates more drag, which can impact the efficiency and maneuverability of a flying object.

## Can the area of an airfoil cross-section be changed?

Yes, the area of an airfoil cross-section can be changed by altering the shape or size of the airfoil. This can be done by adjusting the chord length, thickness, or camber of the airfoil, or by using flaps or other aerodynamic devices to modify the shape of the airfoil during flight.