The number of distinct ARM Instruction Set Architectures (ISA) versions has slowly increased, with Arm adding a new version every few years. The oldest ISA version in common use today is ARMv6, with the ARMv6 ISA (ARM11) found in the original Raspberry Pi SBC and Raspberry Pi Zero (BCM2835). The ARMv6 ISA was introduced in 2002, followed by ARMv7 in 2005 (start of Cortex-A series) and ARMv8 in 2011. The latter was notable for adding 64-bit support.
With ARMv7 being the first of the Cortex cores, and ARMv8 adding 64-bit support in the form of AArch64, what notable features does ARMv9 bring to the table? As announced earlier this year, ARMv9’s focus appears to be on adding a whole host of features that should improve vector processing (vector extensions, or SVE) as well as digital signal processing (DSP) and security, with its Confidential Compute Architecture (CCA).
In addition to this, ARMv9 also includes all of the features that were added with ARMv8.1, v8.2, v8.3 and so on. In essence, this makes an ARMv9-based processor theoretically capable of going toe-to-toe with the best that Intel and AMD have to offer.
You don’t have to look very hard to find another rousing success by SpaceX. It’s a company defined by big and bold moves, and when something goes right, they make sure you know about it. From launching a Tesla into deep space to the captivating test flights of their next-generation Starship spacecraft, the private company has turned high-stakes aerospace research and development into a public event. A cult of personality has developed around SpaceX’s outlandish CEO Elon Musk, and so long as he’s at the helm, we can expect bigger and brighter spectacles as he directs the company towards its ultimate goal of putting humans on Mars.
Of course, things don’t always go right for SpaceX. While setbacks are inevitable in aerospace, the company has had a few particularly embarrassing failures that could be directly attributed to their rapid development pace or even operational inexperience. A perfect example is the loss of the Israeli AMOS-6 satellite during a static fire of the Falcon 9’s engines on the launch pad in 2016, as industry experts questioned why the spacecraft had even been mounted to the rocket before it had passed its pre-flight checks. Since that costly mistake, the company has waited until all engine tests have been completed before attaching the customer’s payload.
SpaceX’s concept art for propulsive landing
But sometimes the failure isn’t so much a technical problem as an inability for the company to achieve their own lofty goals. Occasionally one of Musk’s grand ideas ends up being too complex, dangerous, or expensive to put into practice. For instance, despite spending several years and untold amounts of money perfecting the technology involved, propulsive landings for the Crew Dragon were nixed before the idea could ever fully be tested. NASA was reportedly uncomfortable with what they saw as an unnecessary risk compared to the more traditional ocean splashdown under parachutes; it would have been an impressive sight to be sure, but it didn’t offer a substantive benefit over the simpler approach.
A similar fate recently befell SpaceX’s twin fairing recovery ships Ms. Tree and Ms. Chief, which were quietly retired in April. These vessels were designed to catch the Falcon’s school bus sized payload fairings as they drifted down back to Earth using massive nets suspended over their decks, but in the end, the process turned out to be more difficult than expected. More importantly, it apparently wasn’t even necessary in the first place.
Thirty-five years ago, radiation alarms went off at the Forsmark nuclear power plant in Sweden. After an investigation, it was determined that the radiation did not come from inside the plant, but from somewhere else. Based on the prevailing winds at that time, it was ultimately determined that the radiation came from inside Soviet territory. After some political wrangling, the Soviet government ultimately admitted that the Chernobyl nuclear plant was the source, due to an accident that had taken place there.
Following the disaster, the causes have been investigated in depth so that we now have a fairly good idea of what went wrong. Perhaps the most important lesson taught by the Chernobyl nuclear plant disaster is that it wasn’t about one nuclear reactor design, one control room crew, or one totalitarian regime, but rather the chain of events which enabled the disaster of this scale.
To illustrate this, the remaining RBMK-style reactors — including three at the Chernobyl plant — have operated without noticeable issues since 1986, with nine of these reactors still active today. During the international investigation of the Chernobyl plant disaster, the INSAG reports repeatedly referred to the lack of a ‘safety culture’.
Looking at the circumstances which led to the development and subsequent unsafe usage of the Chernobyl #4 reactor can teach us a lot about disaster prevention. It’s a story of the essential role that a safety culture plays in industries where the cost of accidents is measured in human life.
When Paul Allen founded Stratolaunch in 2011, the hope was to make access to space cheaper and faster. The company’s massive carrier aircraft, the largest plane by wingspan ever to be built, would be able to carry rocket-powered vehicles up into the thin upper atmosphere on short notice under the power of its conventional jet engines. The smaller vehicle, free of the drag it would incur in the denser atmosphere closer to the ground, could then be released and continue its journey to space using smaller engines and less propellant than would have been required for a conventional launch.
But Allen, who died in October of 2018, never got to see his gigantic plane fly. It wasn’t until April 13th, 2019 that the prototype carrier aircraft, nicknamed Roc, finally got to stretch its 117 meter (385 feet) wings and soar over the Mojave Desert. By that time, the nature of spaceflight had changed completely. Commercial companies were putting payloads into orbit on their own rockets, and SpaceX was regularly recovering and reusing their first stage boosters. Facing a very different market, and without Allen at the helm, Stratolaunch ceased operations the following month. By June the company’s assets, including Roc, went on the market for $400 million.
Finally, after years of rumors that it was to be scrapped, Allen’s mega-plane has flown for the second time. With new ownership and a new mission, Stratolaunch is poised to reinvent itself as a major player in the emerging field of hypersonic flight.
Many years ago, I took a summer trip to the Maryland shore with some friends. One of my buddies and I got bored with playing football on the beach, so we decided to take a hike on one of the many trails back into the wooded area behind the dunes. At the trailhead we noticed a prominent sign, warning about the presence of “very aggressive mosquitos” and not to enter without first applying ample insect repellent. We scoffed at the warning as only young idiots could and soldiered on, bare-legged and confident that we’d be fine.
About three minutes into our hike, a small group came pelting down the trail in a panic. “It’s true! Turn back!” they shouted as they flew past us. Undeterred, or at least unwilling to appear that way to each other, we pressed on, only to discover a few minutes later that we were making a substantial blood sacrifice to the next generation of mosquitos on Assateague Island. We couldn’t bear more than a few seconds before turning tail and running back to the beach and jumping into the ocean to get rid of the last few dozen bloodsuckers.
I learned a valuable lesson from that experience, as well as developing a deep and abiding hatred of mosquitos. It turns out I’m in good company — pretty much everyone hates mosquitos, which are not just a nuisance but can be downright dangerous to be around. But if tests with genetically engineered mosquitos currently underway in Florida turn out well, we may be able to finally turn the tide against mosquito-borne diseases, simply by killing all the females before they ever reach adulthood.
If there’s one thing humans hate, it’s exercising willpower. Whether its abstaining from unhealthy foods, going to bed early, or using less energy and reducing greenhouse gas emissions, we’re famously bad at it. Conversely, if there’s one thing humans love, it’s a workaround. Something that lets us live our lives as the carefree hedonists we are, and deals with the sticky consequences so we don’t have to.
Whether gasoline, diesel, or electric, automakers work hard to wring every last drop of mileage out of their vehicles. Much of this effort goes towards optimising aerodynamics. The reduction of drag is a major focus for engineers working on the latest high-efficiency models, and has spawned a multitude of innovative designs over the years. We’ll take a look at why reducing drag is so important, and at some of the unique vehicles that have been spawned from these streamlining efforts.
