From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Comparing the propeller hub and adjusting rod of a Leitner-Watts design to an in-house version.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan87 | |
| Date | 12th June 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. EXPERIMENTAL REPORT. -4- Expl. No. REF Hs{Lord Ernest Hives - Chair}/TAG/LG15.8.25, Points about the Propeller hub etc. The diagram of the propeller hub for a two-blade propeller as given in the pamphlet issued by Leitner-Watts is a little different to our hub with regard to the adjusting rod. In the accompanying sketch it will be seen that the adjusting rod 'X' is much longer than ours and is screwed so far down to take the lock nut 'A' which is used when adjusting the blades only. This nut is for holding the blades after the required setting has been obtained until the main bolts are tightened down after which the lock nut 'A' is removed. When adjusting the blades in the hub which we make, allowance has to be made for when the main bolts are being tightened because the blades move as the caps are bedding down on to the blade sleeve. There is no reason why a lock nut of the ordinary type could not be fitted permanently on this rod, because the Leitner-Watts nut has to be removed and carried somewhere else on the machine, thus running the risk of being lost. While from the weight point of view the ordinary nut would be much the lighter than the elaborate arrangement of the other type. Another point about the Leitner-Watts adjusting rod is that it is tapered at the end, so that when assembling the airscrew on the hub, the rod has a lead into the various holes, whereas, in our case it is a difficult job to guide the rod through on account of it being short and the end being square. Hub scale. The marks of the hub scale are rather a long contd :- | ||