Old 29th Mar 2011, 06:44
  #22 (permalink)  
dClbydalpha
 
Join Date: Jan 2011
Location: on the cusp
Age: 48
Posts: 217
Firstly comfort is a very subjective thing, based on noise, heat, light, vibration and movement, so there is no one answer. Noise tends to be worse nearer the engines. But most people are disturbed by movement.

An aircraft will tend to rotate about its centre of gravity. Any force not applied through the CG will create a rotation as well as a displacement. The position of the CG is controlled carefully to ensure that the aircraft is balanced. The two large forces on an aircraft are lift and weight, for stability reasons it is good to keep them fairly close together, and so the CG is placed near the wings. The further away from the CG you are, either forward or rearward, the more pronounced any movement due to rotation is. Most people find sitting forward to be smoother, and this is due to the change in motion experienced due to displacement and rotation.

If you see an aircraft taking off, as it rolls down the runway it gets to a point where it rotates and then takes off. When it rotates the nose goes up and the tail goes down as the aircraft climbs overall. For those in front of the CG they will feel themselves lifted up first by the rotation and then by the climbing of the aircraft. In the rear they will feel themselves descend first due to the rotation and then climb. So although, everybody is lifted overall, those in the front experience it differently to those in the back. This change from down to up can be quite disturbing to the equilibrium. In my understanding this is why it is better to sit forward than rearward, but to minimise this effect get as close to the wings as possible.

Last edited by dClbydalpha; 29th Mar 2011 at 12:57. Reason: typo correction
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