Bombsight and navigation equipment used on the Dams Raid
These remarkable pictures show three items given by Ettrick Maltby to Gerald Brodribb. When the Maltbys retired they decided that they wanted them left at Hydneye House School so that future generations of boys could see them.
Ettrick Maltby wrote an accompanying note to Gerald Brodribb to explain what the items were. The note is not dated, but was probably written around April 1955, when they finally moved out.
Unfortunately the school was forced to close in 1968-9 following a Compulsory Purchase Order when the area became scheduled for redevelopment. Gerald Brodribb gave the items to an old boy of the school for his budding aerospace collection, and they have remained in his hands ever since. This is the first time they have been displayed in public for nearly 40 years.
The bombsight is thought to be the only surviving example of those which were made for the Dams Raid. Not all the bomb aimers used the sight, which was devised by Wg Cdr C L Dann, supervisor of aeronautics at the Royal Aeronautics Establishment at Boscombe Down. Many used their own makeshift systems for working out the release points, with pieces of string and chinagraph marks on the perspex blister, but now it seems certain that John Fort preferred this sight.
It is not clear what all the numbers stamped on the handle refer to, although the figure 29.5 would seem to be the angle in degrees between the two arms.
Although the two arms are adjustable by means of a wingnut, each arm is locked in position with a small panel pin which can be seen just to the left of the wingnut.
The metal plate was obviously added later when the sight went on display. The varnish was probably also applied at this time.
Pictures courtesy Astrocollection.