757 Fuselage Ripples

[stilton]

I Have noticed that all 757's over time develop small but noticable
ripples/wrinkles on the fuselage skin just behind the trailing edge
of the wing extending several feet back, they do not even feel pronounced to the touch, anyone else notice this, have any ideas
as to the cause?

[Notso Fantastic]

It's caused by the stresses over time of a long, thin fuselage making positive landings in the middle. These ripples are visible on 757s, 737s, even 747s, and no doubt virtually all jets in service!

[Boss Raptor]

look closely at most airliners which have yet to reach a point in their Aging Acft Program - say 20-25 years - where remedial work and/or re-skinning are required...have seen it regularly on 707, A300, 727 and 747

Most acft have them somewhere - some worse than others depending on utilisation Hours and more usually Cycles/Landings

Depending on design some types appear worse than others because of the light/perspective

Have a look at the B52 at Duxford for an example of real wrinkling of the skin on the ribs!

http://www.airliners.net/open.file/213465/M/

[stilton]

I realize these will develop over time, what I found surprising about the 757, at our airline is that they appeared within a month
of new aircraft delivery.

[Boss Raptor]

This area of ripples appears common on most of the Boeings - I stand to be corrected but it appears to be a non pressurised area - side of the wheel bay, body/wing join, not that structurally critical?

Again on 707, 737 and 727 it was very common forward of the E-F posts in front of the cockpit and pressure bulkhead - as well as on the 707 rear area like the 747 pic and like the 757?

Be interested on some more indepth qualified input?

[codpiece face]

The areas mentioned are all pressurised on the 757 from the front pressure bulkhead ie where the radome finishes to the rear pressure bulkhead just aft of the number 4 doors. There is a section underneath where the aircon packs and gear wheel wells are but teh is not any metal skin covering these only composite doors. The ripple affect is sometimes referred to as panting and is quite normal on the boeing aircraft.