The February 2023 issue of IEEE Spectrum is here!

Close bar

Gigantism Is a Never-Ending Temptation for Engineers and Designers

From the pyramids to the Hummer, more is often less

3 min read

There is a fundamental difference between what can be designed and built and what makes sense. History provides a lesson in the shape of record-setting behemoths that have never since been equaled.

The Egyptian pyramids started small, and in just a few generations, some 4,500 years ago, there came Khufu’s enormous pyramid, which nobody has ever tried to surpass. Shipbuilders in ancient Greece kept on expanding the size of their oared vessels until they built, during the third century BCE, a tessarakonteres, with 4,000 oarsmen. That vessel was too heavy, too ponderous, and therefore a naval failure. And architect Filippo Brunelleschi’s vast cupola for Florence’s Cathedral of Santa Maria del Fiore, built without scaffolding and finished in 1436, was never replicated.

The modern era has no shortage of such obvious overshoots. The boom in oil consumption following the Second World War led to ever-larger oil tankers, with sizes rising from 50,000 to 100,000 and 250,000 deadweight tonnes (dwt). Seven tankers exceeded 500,000 dwt, but their lives were short, and nobody has built a million-dwt tanker. Technically, it would have been possible, but such a ship would not fit through the Suez or Panama canals, and its draft would limit its operation to just a few ports.

The economy-class-only configuration of the Airbus A380 airliner was certified to carry up to 853 passengers, but it has not been a success. In 2021, just 16 years after it entered service, the last plane was delivered, a very truncated lifespan. Compare it with the hardly puny Boeing 747, which will see its final delivery in 2022, 53 years after the plane’s first flight, an almost human longevity. Clearly, the 747 was the right-sized record-breaker.

Of course, the most infamous overshoot of all airplane designs was Howard Hughes’s H-4 Hercules, dubbed the Spruce Goose,” the largest plane ever made out of wood. It had a wingspan of nearly 100 meters, and it was propelled by eight reciprocating engines, but it became airborne only once, for less than a minute, on 2 November 1947, with Hughes himself at the controls.

Another right-size giant is Ford’s heavy and powerful F-150, now in its 14th generation: In the United States, it has been the bestselling pickup since 1977 and the best-selling vehicle since 1981. In contrast, the Hummer, a civilian version of a military assault vehicle, had a brief career but is now being resurrected in an even heavier electric version: The largest version using an internal combustion engine, the H1, weighed nearly 3.5 tonnes, the electric Hummer, 4.1 tonnes. I doubt we will see 14 generations of this beast.

But these lessons of excess carry little weight with designers and promoters pursuing record sizes. Architects discuss buildings taller than a mile, cruise ship designers have already packed nearly 7,000 people into a single vessel (Symphony of the Seas, built 2018) and people are dreaming about much larger floating cities (perfect for spreading the next pandemic virus). There are engineers who think that we will soon have wind turbines whose more than 200-meter diameter blades will fold, like palm fronds, in hurricanes.

Depending on where you stand you might see all of this either as an admirable quest for new horizons (a quintessential human striving) or irrational and wasteful overreach (a quintessential human hubris).

This article appears in the January 2022 print issue as “Extreme Designs.”

Gigantism in the Air

Overhead view of a Hughes H-4 Hercules

John MacNeill

Hughes H-4 Hercules (“Spruce Goose”): Wingspan: 97.82 meters. Length: 66.65 meters.

The Conversation (2)
Daniel Jassby29 Jan, 2022
LM

The giant ITER tokamak currently under construction is another example of technology “overshoot.”  Assuming that it is actually completed, ITER may turn out to be the Spruce Goose of the fusion R&D world.

Undaunted, fusion energy enthusiasts in the European Union and Asian countries are designing so-called Demonstration fusion reactors that are supposed to follow ITER and look like ITER on steroids.  Fortunately, all these projects will collapse in their design phase.

FB TS21 Dec, 2021
INDV

IMHO the (revolutionary) future of airliners is NOT simply making current designs much bigger (like Airbus A380) nor going hypersonic nor switching to flying wing/body designs!

What is really needed is making airliners much bigger but also making them much safer & able to takeoff/land vertically or from/to extremely short/simple/cheap runways anywhere!

How?

For example, imagine joining together 2 or 3 fuselages & adding 2 or 3 sets of main wings that has highly adjustable angle of attack (& no other complex mechanisms/flaps etc)!

How Duolingo’s AI Learns What You Need to Learn

The AI that powers the language-learning app today could disrupt education tomorrow

9 min read
Vertical
This playful illustration shows Duolingo’s owl mascot, cut away down the midline, showing hidden inside a high-tech skeleton suggestive of some sort of AI robot.
Eddie Guy
Blue

It’s lunchtime when your phone pings you with a green owl who cheerily reminds you to “Keep Duo Happy!” It’s a nudge from Duolingo, the popular language-learning app, whose algorithms know you’re most likely to do your 5 minutes of Spanish practice at this time of day. The app chooses its notification words based on what has worked for you in the past and the specifics of your recent achievements, adding a dash of attention-catching novelty. When you open the app, the lesson that’s queued up is calibrated for your skill level, and it includes a review of some words and concepts you flubbed during your last session.

Duolingo, with its gamelike approach and cast of bright cartoon characters, presents a simple user interface to guide learners through a curriculum that leads to language proficiency, or even fluency. But behind the scenes, sophisticated artificial-intelligence (AI) systems are at work. One system in particular, called Birdbrain, is continuously improving the learner’s experience with algorithms based on decades of research in educational psychology, combined with recent advances in machine learning. But from the learner’s perspective, it simply feels as though the green owl is getting better and better at personalizing lessons.

Keep Reading ↓Show less
{"imageShortcodeIds":[]}