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A 707 being a much older plane with relatively stiff wings compared to the 787. What percentage would the g forces be reduced on a 787 given its wing flex?

And yes, I mean if the 707 and 787 were flying through the exact same turbulence at the same time.

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    $\begingroup$ The B787 has a gust alleviation system that likely has a much greater impact than the wing flexibility. Related: Does the 787 gust alleviation system make a more comfortable ride or for a more stable aircraft? $\endgroup$ – Gerry May 17 at 12:30
  • $\begingroup$ @Gerry is there any data on what % turbulence g factor would be reduced? Ie if it went through the same turbulence as the hypothetical 707 in my post title. $\endgroup$ – Warden May 17 at 13:38
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    $\begingroup$ I expect that Boeing's flight controls group may have access to the raw data needed to make the comparison. That doesn't mean they've actually compared the two platforms. It's also unlikely that any significant data has been published outside Boeing as it would be considered proprietary. $\endgroup$ – Gerry May 17 at 16:59
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The 787 will not experience lower G-forces, it will experience them later. If the turbulence is of short duration, the 787 might not register much while a 707 is shaken thoroughly. If the updraft persists, both aircraft will eventually feel the same forces.

When an aircraft enters turbulence, the wings experience more lift and start moving upwards. If the wings are heavy (full tanks) and floppy, it takes quite a while before the fuselage experiences any forces. After the wings reached their upper bending limit, the fuselage starts moving upwards together with the wings. In an aircraft with lightweight, stiff wings, the fuselage follows any wing movement immediately.

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G-forces caused by turbulence are instantaneous. The wings will not "cushion" the aircraft to mitigate the force of the turbulence. The additional flexibility of the wings means that they will absorb more energy and dissipate them without damage to the structure.

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