What Does the Original Jeep Have In Common With the Mercedes-Benz W25 Grand Prix Car?
Preparing for next year's 100th anniversary, SAE has had Centennial items in its members' monthly SAE Updates. A recent one celebrated D.G. "Barney" Roos and his efforts in development of the ubiquitous Jeep.
Willys-Overland won the contract for a rugged all-purpose military vehicle, but its prototype was 263 lb. overweight. Roos and his engineering team analyzed every bolt, washer and bracket. Components were downsized wherever feasible, but neither power nor durability could be sacrificed.
The final margin was so slim that Roos calculated a second coat of paint would break the limit. Hence, the original Jeep weighed in at a svelte 2160 lb. with but a single coat of paint.
And so it was with the 1934 Mercedes-Benz W25 Grand Prix car. As detailed in Karl Ludvigsen's wonderful Mercedes-Benz Quicksilver Century, the Grand Prix regulations for 1934-1936 were quite liberal: Any displacement, any sort of forced induction, but car weight, without tires and liquids, could not exceed 750 kg (1654 lb.).
The response to the 750-kg Formula was the W25, powered by a potently supercharged 3.3-liter dohc 4-valve-per-cylinder straight-8. Following the practice of international racing at the time, the cars, being German, were painted white. (Other liveries included Italian red, British green, French blue, Belgian yellow and, with American Whitney Straight running occasionally, American blue and white).
The shiny new white cars weighed in at 752 kg! Last-minute changes, At the first Grand Prix, like a small but necessary air scoop, had put them over the limit. What to do?
Ludvigsen's research doesn't identify just who thought of it, but the solution was to strip off the carefully finished white paint (and the accompanying lead filler), then follow this with a single light coat of silver. Thus, the Silberpfeile, Silver Arrows; and thus, what the W25 Grand Prix car has in common with the .
Searching For Oil Can Have Interesting Side Benefits
Gleaning information on one thing and another, I often come upon neat tidbits that have little to do with whatever I'm researching. For instance, could the Bedout (pronounced "Be-doo") High be related to the largest mass extinction ever?
This seems peripheral to R&T until you learn that it was oil exploration that gave rise to the question. The Bedout High is a submerged peak off the northwest coast of Australia, in a region given lots of seismic probing by oil geologists. Some of them think it was formed 250 million years ago by the impact of a large asteroid or comet. They hypothesize that this event triggered the Permian-Triassic Extinction, a geologic tick mark in time every bit as striking as the one associated with the Chicxulub Impact on the Yucatan Peninsula. (This latter one killed off the dinosaurs.) Others claim Bedout could have just as well been caused by volcanic action.
Both sides in this geologic squabble use the samples, tools and techniques of oil exploration. Thus, even if no giant oil fields are discovered, at least our knowledge is advanced.
A Weighty Matter
The kilogram is the only unit of measure still defined by a physical object. Did you know this? I hadn't, until I read about it in my weekly Science magazine, published by the American Association for the Advancement of Science.
By contrast, length and time depend on physical laws, not an artifact. The basic unit of time, one second, is defined in terms of a cesium atom's natural frequency, 192,631,770 cycles of it. The basic unit of length, one meter, is the distance traveled by light in vacuum during 1/299,792,458 second. But the basic unit of mass, one kilogram, is a cylinder of platinum/iridium alloy. The official one, le Grand K, resides in Paris. Other siblings around the world are checked against it every 10 years or so.
Researchers see this lump of stuff as an inherent flaw in the scientific method. How do we know that le Grand K and its siblings aren't changing over time?
Other approaches are being discussed. One, sort of an electrical balance beam, associates the kilogram with Planck's Constant. Another, counting atoms, has the Avogadro Number as its constant. A third measures ion accumulation of gold atoms. Each has its complications, and, as of this writing, le Grand K still rules.