Upon removal of the fabric from the upper mainplane it was discovered that an extensive number of the ribs were damaged.
Work has been underway to repair this damage and give the wing much of its original strength.
The presence of pre existing repairs indicate that this damage took place prior to the last restoration. Although some damage appears to be as a result of handling and impact, many of the ribs also exhibit a characteristic splitting across the thin section of the rib web. This typically occurs 15 to 20 millimetres either side of the central nail holding the vertical reinforcing stave and is a result of different rates of contraction between the cross grain of the parent rib web and the long grain of the reinforcing stave.
This is an interesting example of an element of the design originally intended to provide strength actually resulting in damage in the longer term.
The coarse timber panel repairs nailed to the faces of the ribs have been removed, losses have been filled with precisely shaped timber fills and local reinforcing in the form of 1.6 millimetre plywood has been applied to the rib faces where required.
Care has been taken to avoid obscuring the original production rib numbering stamps.
All new additions have been labelled AWM 08 so as to identify them to future repairers or conservators.