Apparently, we Europeans know of no standards as being "de facto international," but they all shall be ratified by the global community in majority vote—regardles of the power and wealth of individual voting bodies.

To us Europeans it seems rather strange, that although the Systme Internationale d'UnitŽs is the only system in the U.S.A. standing as its primary weights and measures system, no dedicated effort is being made to replace the customary system now still in use. It ought to be recognized that those suffering the most from this situation, are the citizens of the U.S.A.—not us Europeans.

I would like to know whether the additive was liquid or suspended particles and how the oil company removed the additive. I think that this technique could be applied to molten polymer lines where production speed is often limited by the pressure drop in the production lines between a final reactor and pelletizer. We would not want to add a potentially costly additive to act as a lubricating agent that gets shipped to the customer (like fluoropolymer additives for extrusion die lubrication). If the additive could be removed before pelletizing, then the cost could be minimized with recycling.

Does anyone know additional details about the polymer additive for oil transport and its removal technique? Thanks for any insight.

I remain skeptical, yet I applaud the direction of the effort, producing hydrogen on-board and only as needed to fuel an internal combustion engine, as opposed to the fuel-cell/electric approach.

Also, in the same issue, in Letters, Robert Essenhigh correctly identifies the very real hazard of hydrogen on-board. For the hydrogen-fueled automobile application, I believe engine shutdown must necessarily be sequential. First, the hydrogen generator is deactivated, the engine continues running, ingesting and burning all of any hydrogen remaining. This could be accomplished by a shaft-driven centrifugal switch in the engine ignition circuit.

If we are truly serious about cleaning up this planet, hydrogen is the way to go. I would hope that we have the wisdom and the political will to make it a reality.

They are correct that the first wind tunnel was not built by the Wright brothers in 1901, but by Francis Herbert Wenham for the British Aeronautical Society in 1871. A steam engine drove the fan. Measurements of lift and drag on plane surfaces were measured.

The principle of the wind tunnel that is relevant to aviation research had been recognized 300 years earlier by Leonardo da Vinci.

Orville and Wilbur Wright were the first to use a wind tunnel to experimentally determine the wing curvature that would produce best lift-to-drag ratio. They did this for their 1902 glider. They then used these results to determine the best propeller shape as a function of distance from the center for their first controlled powered flight of a heavier-than-air machine in 1903.

Alberto Santos-Dumont was an important early aviator. His adventurous life is well described in a 1997 biography, Man Flies, by Nancy Winters. He was born in 1871, grew up with steam engines and, later, internal combustion engines on the huge family-owned coffee plantation in Brazil. While being home-schooled by his sister, he indulged in the scientific fantasies of Jules Verne.

He recognized the weight and power advantage of the gasoline engine over the steam engine, but was warned about excessive vibrations for an airship. He mounted the engine in a tree and showed that it vibrated less than on the ground. Vibration amplitude was decreased because the engine forcing frequency was much higher than the natural frequency of the tree limb and also higher than the natural frequency of an airship mount.

Santos-Dumont made the first gasoline engine-powered controlled flight of a lighter-than-air ship around the Eiffel Tower in 1901. He repeated this feat with a heavier-than-air machine in 1906.

Goddard died before von Braun came to America. Von Braun paid respectful tribute to Goddard's work and was surprised that the American military had not used Goddard's rocket research to develop a weapons delivery system.

Von Braun became director of the Army Ballistic Missile Agency at Redstone Arsenal and developed the Redstone/Jupiter rockets that launched the U.S.'s first satellite and first man in space. As NASA was created, the western part of Redstone Arsenal became NASA's Marshall Space Flight Center.

Von Braun became director at Marshall and directed the development of the Saturn V that sent Americans to the moon. The Titan II and Atlas rockets also played significant roles in the NASA manned space program. Mercury was powered by Redstone (designated Jupiter for launch missions) and Atlas rockets, Gemini by Titan II, and Apollo by Saturn rockets.

At the end of World War II, the Soviets tried to capture von Braun and his team. The von Braun team came to America and played a most significant role in developing the early U.S. missile and space programs and in putting Americans on the moon.

To write about the history of America's early space program and the lunar landings, and make no mention of von Braun is wrong.

Now, I am 15 and designing my own creations. I did not build them yet, but if my calculations and theories are correct, they should work.

I just wanted to tell you that the Internet site of memag is phenomenal. I even made it my homepage. It keeps me up to date with what mechanical engineers are doing to further our advances in technology. It's just great.

home | features | news update | marketplace | departments | about ME | back issues | ASME | site search

© 2001 by The American Society of Mechanical Engineers