Westinghouse Air Spring Option

[alsfarms]

Thanks for the update.....

Al

[Jonathan Reeve]

John J McElroy, then chief engineer of the Westinghouse Air Spring Company, wrote a two part article in the Transactions of the SAE for February 1924 of which I have a print of part 2. (pages 272-322 plus an addendum to part 1 to correct a key misprint in part 1 on page 257; part 1 with erroneous diagrams was printed in the report of the December 1923 meeting, which I don't have). He reports in part 2 a lot of testing done on a test road (with potholes) and this might interest current owners who understand Hooke's law and Boyle's law. For those interested in how all scientists "Stand on the Shoulders of Giants" may like to be reminded that  Hook started out as Boyle's lab boy at my alma mater! The diagram on p 257 shows the two laws contrasted as they apply to cars with and without air in their suspension.

This sudden candour by McElroy and  the Company might have been provoked by the arrival of low pressure tires that with front wheel brakes brought a lot of heart-ache connected with wheel wobble or shimmy. McElroy claims that airsprings were just as useful with high and low pressure tires.

The genius who solved this shimmy problem first was G-B Falchetto of Lancia, who designed a front brake system with 2WB levels of unsprung weight. As Rolls-Royce engineers declared publicly, they had to modify Lancias "extensively" to provoke shimmy and owners who replaced the Lambda's long front fenders with cycle fenders were later also able to achieve shimmy at 60 mph.