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Comment on "Ram Wing Surface Effect Boat"

1974; American Institute of Aeronautics and Astronautics; Volume: 8; Issue: 2 Linguagem: Inglês

10.2514/3.62982

1555-5909

Alexander Lippisch,

Sports Dynamics and Biomechanics

vides of incidence control. I feel that the words between quotation marks cannot possibly express the authors' real views. As far as I can judge, Bras d'Or's incidence is under complete control. All that these words do is belittle G's role in Bras d'Or's operation. The whole article tends to convey the impression that Bras d'Or functions on the surface piercing principle, augmented by something unnamed, which on analysis appears to be G's angle of attack control. No data are furnished to show in what measure the two principles actually divide between themselves the task of controlling lift. That would be inconsequential if Bras d'Or were presented as a hybrid configuration. But under the circumstances, there is a need for more precise data. One is reduced to conjectures. I have reasons to believe that Grunberg's contribution to lift control is not secondary at all, and I would not be surprised if variable angle of attack were the senior partner in its association with area variations. 5) Having covered my own case, I feel the responsibility to add a few words on behalf of those whose voices are stilled. The undisputed father of area control is Forlanini, but his was the ladder version. Crocco substituted surface piercing for the ladder. It would seem that research into the other (not-Grunberg) branch of Bras d'Or's family tree should have lead either to Forlanini, the distant progenitor, or, closer, to Crocco. Our admiration for the father of the telephone cannot be dimmed by the recognition that in hydrofoils Bell and Baldwin were only apostles of Forlanini's gospel. They visited Forlanini in Italy, studied his boat, purchased his patents. After several less successful models, thanks to sound engineering and with some improvements, by no means basic, they produced the excellent HD-4, of the ladder type. The HD-4 does not even appear to be in direct line of Bras d'Or's ancestry. I have sympathy for Forlanini and Crocco, who more than anyone else deserve to be remembered in their descendents of the surf ace-piercing type.