Technologies

Blade Runner: 18-Rotor “Volocopter” Moving from Concept to Prototype

It may look "nutty" and like a "blender," but the designers say the craft could challenge helicopters

Inventor and physicist Thomas Senkel created an Internet sensation with the October 2011 video of his maiden—and only—test flight of a spidery proof-of-concept 16-rotor helicopter dubbed Multicopter 1. Now the maker of the experimental personal aviation craft, the European start-up e-volo, is back with a revised “volocopter” design that adds two more rotors, a serial hybrid drive and long-term plans for going to 100 percent battery power.

The new design calls for 1.8-meter, 0.5-kilogram carbon-fiber blades, each paired with a motor. They are arrayed around a hub in two concentric circles over a boxy one- or two-person cockpit.

After awarding the volocopter concept a Lindbergh Prize for Innovation in April, Yolanka Wulff, executive director of The Charles A. and Anne Morrow Lindbergh Foundation, admitted the idea of the multi-blade chopper at first seems “nutty.” Looking beyond the novel appearance, however, she says, e-volo’s concept excels in safety, energy efficiency and simplicity, which were the bases of the prize.

All three attributes arrive thanks largely to evolo’s removal of classic helicopter elements. First, the energy-robbing high-mass main rotor, transmission, tail boom and tail rotor are gone. The enormous blades over a normal chopper’s cabin create lift, but their mass creates a high degree of stress and wear on the craft. And the small tail rotor, perched vertically out on a boom behind the cabin, keeps the helicopter’s body from spinning in the opposite direction as the main blades, but it also eats up about 30 percent of a helicopter’s power.

The volocopter’s multiple rotor blades individually would not create the torque that a single large rotor produces, and they offer redundancy for safety. Hypothetically, the volocopter could fly with a few as 12 functioning rotors, as long as those rotors were not all clustered together on one side, says Senkel, the aircraft’s co-inventor and e-volo’s lead construction engineer.

Without the iconic two-prop configuration, the craft would be lighter, making it more fuel efficient and reducing the physical complexity of delivering power to the top and rear blades from a single engine. Nor would the volocopter need an energy-hungry transmission. In fact, “there will be no mechanical connection between the gas engine and the blades,” Senkel says. That means fewer points of energy loss and more redundancy for safety.

E-volo’s design eliminates the dependence on a single source of power to the blades. As a serial-hybrid vehicle, the volocopter would have a gas-fueled engine, in this case an engine capable of generating 50- to 75 kilowatts, typical of ultralight aircraft. Rather than mechanically drive the rotors, the engine would generate power for electric motors as well as charge onboard lithium batteries. Should it fail, the batteries are expected to provide enough backup power so the craft could make a controlled landing.

Whereas helicopters navigate by changing the pitch of the main and tail rotor blades, the volocopter’s maneuverability will depend on changing the speed of individual rotors. Although more complex, it is more precise in principle to control a craft using three to six redundant microcontrollers (in case one or more fails) interpreting instructions from a pilot using a game console–like joystick—instead of rudder pedals, a control stick and a throttle.

Wulff’s first impression about the volocopter’s design is not uncommon. E-volo’s computer-animated promotional videos of a gleaming white, carbon-fiber and fiberglass craft beneath a thatch of blades recall the many-winged would-be flying machines of the late 19th century. This point is not lost on Senkel.

“I understand these skeptical opinions,” he says. “The design concept looks like a blender. But we really are making a safe flying machine.”

That would be progress in itself. Multicopter 1 looked like something from an especially iffy episode of MacGyver, complete with landing gear that involved a silver yoga ball. Senkel rode seated amid all those rotors powered only by lithium batteries. Multicopter 1 generated an average of 20 kilowatts for hovering and was aloft for just a few minutes.

There’s a reason why the experimental craft flew briefly and only once.Senkel describes that first craft as “glued and screwed together.” Seated on the same platform as the spinning blades, he says, “I was aware of the fact that I will be dead, maybe. Besides, we showed that the concept works. What do we win if we fly it twice?” he asks rhetorically.

Other than putting the pilot safely below the blades, the revised volocopter design would operate largely the same as the initial prototype. The design calls for three to six redundant accelerometers and gyroscopes to measure the volocopter’s position and orientation, creating a feedback loop that gives the craft stability and makes it easier to fly, Senkel says.

The volocopter’s revised prototype under construction could debut as soon as next spring. The first production models, available in perhaps three years, are expected to fly for at least an hour at speeds exceeding 100 kilometers per hour and a minimum altitude of about 2,000 meters, still far shy of standard helicopter’s normal operating altitude of about 3,000 meters. “This could change our lives, but I don’t expect anything like that for 10 years,” Senkel adds.

Given that most of the technology needed to build the volocopter is already available, “this idea is fairly easy to realize,” says Carl Kühn, managing director of e-volo partner Smoto GmbH, a company that integrates electric drive systems and related components.

Like Senkel, Kühn has modest short-term expectations despite his repeated emphasis on the standard nature of the technology involved. “I guess that e-volo will have [a prototype] aircraft in three years that can do the job—that it will lift one or two persons from one point to another,” he says.

The biggest immediate limitations appear to be regulatory. For instance, European aviation regulators consider any electrical system greater than 60 volts to be high voltage and regulate such systems more aggressively, Kühn says. As a result, the volocopter will operate below that threshold. The craft will also need to weigh no more than 450 kilograms to remain in the ultralight category, which is likewise subject to fewer government aviation regulations, according to Senkel.

The Lindbergh Foundation’s Wulff says the organization’s judges felt e-volo had “a greater than 50 percent chance of succeeding, or they wouldn’t have given them the innovation award.” Asked if she would line up to fly one someday, she says, “I sure would. It looks very compelling to me.”

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Technologies

Trump Maintains US‑Iran Negotiations Continue Amid Tehran’s Denials of Duplicity

President Trump insists that US‑Iran talks are ongoing despite Tehran’s denial of any negotiation plans, while warning that only a deal or total surrender will allow passage through the Strait of Hormuz. Conflicting statements from both sides have heightened uncertainty as the conflict enters its sixth month.

On Monday, President Donald Trump asserted that negotiations between the United States and Iran are still taking place, even after Tehran stated it has no intention of engaging in direct talks with Washington.

In a fiery Truth Social post, Trump labeled Iran’s leaders “unbelievably duplicitous,” claiming they are lying about ongoing peace talks “whether Iran wants to admit it or not.” He repeated his assertion that the United States completely controls the Strait of Hormuz, despite maritime traffic through the crucial route lingering at only a small fraction of pre‑conflict levels.

He wrote, “Nothing reaches Iran unless we allow it, and nothing will pass unless a deal—or total surrender—is achieved.”

Earlier that day, Iranian Foreign Ministry spokesperson Esmail Baghaei told reporters there is no imminent plan for U.S.–Iran negotiations, contradicting Trump’s earlier comment that talks would resume Monday afternoon. Baghaei added that Iran’s only current discussions are with Oman concerning the Strait of Hormuz.

The conflicting statements have heightened uncertainty over the peace‑talk process and the broader conflict, now in its sixth month.

Trump’s assertion about new negotiations came a day after he said on Truth Social that he had agreed to cancel a massive strike against Iran “subject to being able to rapidly make a DEAL.” He said in the same post that Iran and other Middle Eastern countries had asked him to hold off on that attack because “the perimeters of a deal has been agreed to.”

Trump has claimed dozens of times throughout the more‑than‑five‑month‑long war that a deal is at hand. No permanent deal has been signed, and a temporary ceasefire reached in June has fallen apart.

Trump has also repeatedly threatened to launch devastating strikes against Iran before backing off. After the latest example, oil prices on Monday fell and stocks surged.

BMI, a research unit of Fitch Solutions, said in a note Monday that a broader diplomatic understanding on reopening the Strait of Hormuz is still achievable this quarter, while raising the probability of its escalation scenario to 35% from 25%, citing mounting military, diplomatic and economic signs of rising U.S.-Iran tensions.

“Diplomatic progress is likely to be punctuated by periodic military flare-ups, while miscalculation by either side could trigger a renewed escalation,” BMI analysts wrote in a note. The firm said the key issue to watch is the future governance of the strait, as the Iran-Oman talks — potentially backed by Gulf states, China and the U.S. — point to efforts to build a post-conflict shipping framework.

Shipping risks persist even as diplomacy appears to be advancing. The United Kingdom Maritime Trade Operations Centre said it received a report of an incident 20 nautical miles (23 miles) northeast of Khasab, Oman — at the mouth of the strait — with a tanker’s master reporting an explosion in close proximity to the vessel at about 20:37 UTC Sunday (4:37 pm ET). The vessel and crew were safe and authorities are investigating, UKMTO said, advising ships to transit with caution.

The proposal Trump announced over the weekend calls for the U.S. and Iran to return to negotiations and continue ironing out some of the thorny issues that had derailed diplomatic efforts, according to The Associated Press, citing a regional official involved in the mediation efforts.

The official said the proposal also includes a reopening of the Hormuz Strait and halting attacks across the region, including by Iranian-backed militias in Iraq on the Arab Gulf countries and Jordan.

The U.S., for its part, will end its naval blockade on Iran and allow Tehran to export its oil, the official said, adding that no deal has been reached, although the mediation efforts remained underway.

Trump’s weekend reversal has lowered the temperature after days of escalating attacks across the Gulf. Kuwait said Saturday that Iranian forces launched a wave of drones within its airspace, with its military destroying multiple aircraft after Iran targeted critical infrastructure in the country’s north.

A parallel track with Muscat is also advancing. Iranian diplomats said Tehran was close to reaching a new arrangement with Oman to manage shipping through the Strait of Hormuz, a deal critical to preventing the war from escalating further, according to the Financial Times.

Iranian officials said negotiations over future management of the Hormuz Strait with Oman, which sits on the opposite shore of the waterway, are in their final stages. The agreed shipping route would be different from those used before, according to Iran’s Foreign Ministry spokesperson, Baghaei, adding that the new route was separate from the issue of the strait’s reopening or continued closure.

Technologies

Oil Prices Slide as Trump Halts Planned Iran Strike

Oil prices dropped after Trump cancelled a planned strike on Iran, with WTI down about 5% and Brent near 5% lower. He said the move followed requests from Tehran and regional allies for a pause while a deal shaping the Strait of Hormuz and Iran’s nuclear program is negotiated.

Oil prices fell on Monday after President Donald Trump announced he had cancelled a planned strike on Iran. WTI futures dropped roughly 5% to $80.34 a barrel, while Brent slipped about 4.7% to $83.77 a barrel.

Trump said early Sunday he called off the strike after Iran and several Middle Eastern nations asked him to hold off, noting that the outlines of a deal had been agreed upon. He added that the prospective accord would entail the immediate, full opening of the Strait of Hormuz and an end to Iran’s nuclear ambitions, according to his Truth Social post.

The president had been considering another round of strikes as diplomatic hopes waned since the conflict began on February 28. He said the U.S. and Iran would meet for talks on Monday, but Iran denied any scheduled negotiations with Washington, citing PressTV. Iran’s foreign‑ministry spokesperson Esmaeil Baghaei clarified that Tehran was only discussing shipping routes through the Strait of Hormuz with Oman. In a follow‑up Truth Social message, Trump insisted that, regardless of Iran’s acknowledgment, the United States is indeed discussing a solution to a long‑standing problem created by Iran.

Technologies

Oil Prices Drop as Trump Cancels Planned Attack on Iran

Oil prices fell sharply after President Trump announced the cancellation of a planned strike on Iran, citing a new deal that would open the Hormuz Strait and end Iran’s nuclear threat.

Oil prices fell sharply on Monday after President Donald Trump announced that he had called off a planned strike on Iran.

West Texas Intermediate futures, the U.S. benchmark, slipped roughly 5% to close at $80.34 per barrel, while Brent crude, the international benchmark, declined 4.7% to settle at $83.77 a barrel.

Trump made the announcement early Sunday, saying he had canceled the strike following requests from Tehran and other Middle Eastern countries.

In a Truth Social post, he wrote: “We have just been asked by Iran, and other Middle Eastern Countries, to hold off any attack in that the perimeters of a deal has been agreed to.”

The president indicated that the proposed agreement would include the immediate, complete, and total opening of the Hormuz Strait, as well as an end to Iran’s nuclear threat.

Trump had been weighing additional strikes amid diminishing prospects for a diplomatic resolution to the conflict that began on Feb. 28. He stated that the U.S. and Iran would hold negotiations on Monday.

Tehran denied that talks were planned with Washington, according to state news outlet PressTV.

Iran’s Foreign Ministry spokesman Esmaeil Baghaei said Tehran was only holding talks with Oman regarding the routes ships can use through the Strait of Hormuz.

In a subsequent Truth Social post, Trump added that whether “Iran wants to admit it or not, we are, in fact, talking of a solution to a problem that they have caused for decades.”