Palmer tyres
I did a quick search on the web and found this information. its text from a book which appears to be out of copyright.
Elementary principles of aeroplane design and construction : a textbook for students, draughtsmen and engineers (1921), author – Arthur William Judge.
WHEELS.
The lighter wheels of earlier aeroplane practice are now being replaced by much stronger wheels with wide axles and wellsplayed spokes for taking side stresses. The hubs are invariably made plain, with gunmetal-steel bearings for lightness and quick replacement facilities. The sizes of aeroplane wheels vary from 10 inches in the case of the wing-skid tip wheels up to 32 inches for very heavy machines, the standard size for monoplanes and biplanes being about 700 x 85 mm., for total machine weights not exceeding 1,400 pounds.*
A section of an aeroplane undercarriage wheel is given in Fig. 50, showing the method of taking lateral stress by means of four rows of well-splayed spokes and the long bushed hub for the axle bearing.
The wheels are usually fitted with detachable celluloid, metal, or canvas discs, to minimize head resistance. The larger the diameter of the wheel and the greater its width, the better is it adapted to traversing rough ground ; the use of wheels in parallel or in tandem enables the machine to travel over rougher ground, owing to the hollows and crests being “bridged” over better.
It should be here mentioned that the lower the normal landing speed in still air, and the lighter the total weight of the machine, the lighter will be the landing chassis, in construction and weight, and the smaller the section, though not necessarily the diameter, of the wheels.
* For very large machines, such as large twin-engined and multiengined machines, weighing from 8,000 up to 25,000 pounds, wheels varying from 900 x 200 mm., up to 1,500 x 300 mm., are now used; the number of wheels ranges from two in the lighter of these machines, up to as many as eight in the largest.
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