November 15, 2023 - No. 047

In This Issue 

: Rolls-Royce Runs UltraFan To Full Power

: Are two grades of fuel needed in the quest for unleaded avgas?

: NH Company Completes Autonomous Helicopter Flight Test Program

: Lockheed Martin Jets into Nuclear Electrical Spacecraft Power 

: Russian manufacturer test-flies prototype widebody passenger airplane

: Smaller, Lighter Cessna 327 ‘Mini Skymaster’

: Boeing Outlines 777-9 Certification Test Plan

: World’s Biggest Aircraft Makes Its Ground Debut

: B-21 Takes To The Sky For The First Time As Flight Testing Begins

: BETA continues rollout of electric aircraft harging network with Archer Aviation as customer

 

 


Rolls-Royce Runs UltraFan To Full Power
Guy Norris 
November 13, 2023
Credit: Rolls-Royce

Rolls-Royce has run the UltraFan technology demonstrator at maximum thrust at its test facility in Derby, England, marking the highest power yet achieved by a gear-driven turbofan.

Rolls-Royce Runs UltraFan To Full PowerThe engine, which first ran in April, achieved thrust of 85,000 lb. in early November, Rolls says. The power level is around 5,000 lb. higher than the target thrust level for which the demonstrator was designed.

Running in the company’s specially built Testbed 80 facility, the UltraFan is the first all-new centerline big-fan Rolls engine since the Trent XWB-84 in 2010 and comes nine years after the company revealed plans to pursue a geared architecture for its next-generation product line. Rolls adds that the initial stage of the test was conducted using 100% sustainable aviation fuel (SAF).

Although no new applications for the UltraFan have yet been identified, Rolls-Royce CEO Tufan Erginbilgic says the full-power milestone “puts us in a strong position to support the plans of our customers as they develop the next generation of super-efficient aircraft.” Technology from the program, including the widespread use of new materials, is also expected to be spun-off into upgrades of the company’s direct-drive engine family.

Simon Burr, Rolls-Royce group director of Engineering, Technology and Safety, says the UltraFan’s 10% efficiency gain over the company’s current production Trent XWB also underlines its strategy for more sustainable propulsion. 

“We estimate that to reach Net Zero flying by 2050, a combination of highly efficient, latest-generation gas turbines such as UltraFan operating on 100% SAF are likely to contribute around 80% of the total solution, which is why today’s announcement is such an important milestone for Rolls-Royce and the wider industry,” Burr says.

Designed with a 140-in.-dia. fan—some 6-in. wider than the fan on General Electric’s GE9X, the largest turbofan currently flying—the UltraFan incorporates a 50-megawatt power gearbox developed at Rolls-Royce’s Dahlewitz, Germany facility. Other advances include a composite fan system, hybrid ceramic bearings, ceramic matrix composites (CMCs), high torque-density shafts, advanced cast bond turbine blades and second-generation nickel disk superalloys.

The CMC components, primarily used for turbine seal segments, are lighter and more tolerant of high temperatures. Made from a continuous silicon carbide fiber reinforcement with a fiber-matrix interface coating surrounded by a ceramic matrix primarily of silicon carbide, the CMCs and other high temperature features were previously evaluated in the HT3 (High Temperature Turbine Technology) demonstrator based on a Trent XWB-97.

Rolls says the UltraFan architecture is scaleable from 25,000-110,000-lb. architecture and, as part of more advanced studies under Europe’s Clean Aviation aeronautics research program, is involved in the HEAVEN (Hydrogen Engine Architecture Virtually Engineered Novelly) project. HEAVEN is a €35.6 million ($38 million) study aimed at scaling the concept to the short/medium-range market and integrating both hybrid-electric technology and direct hydrogen (H2) combustion.

The HEAVEN team includes academic, research and industrial partners across France, Germany, the Netherlands, Spain, and the UK, and will study an UltraFan H2 version with the goal of achieving a 20% fuel-burn reduction over current engines. HEAVEN is supported by Cavendish, another Clean Aviation program led by Rolls-Royce. Under the €29.2 million project, a design team will integrate lean-burn hydrogen combustion into a Pearl 15 donor engine for ground testing on liquid hydrogen starting in late 2024.

 


 

 


Are two grades of fuel needed in the quest for unleaded avgas?
By Ben Visser · November 8, 2023 

In my last column, “Birds of a feather,” I wrote about the need for an ASTM standard for any new unleaded replacement for 100LL.

I also noted that a committee has been working on a new specification for about 25 years and ASTM is now looking at issuing a separate spec for each individual fuel manufacturer.
I have received several questions from readers asking what the difference is between an ASTM spec and qualifying a new fuel using an STC.

The problem with using an STC is that after 100LL is gone, pilots who are flying cross-country and land at an airport that is supplied by only an STC qualified fuel will not be able to purchase that fuel if he or she does not have the necessary STC.

I feel that it is important that all new unleaded replacements for 100LL be ultimately approved for all applications by all active manufacturers.

An STC approval may work for a start-up, but by the time 100LL is fully eliminated, the replacement products need to be qualified against an approved standard. This standard (or standards) need to be acceptable and agreed upon by all parties, including the FAA, the engine manufacturers, and the airframe manufacturers.

The most common suggestion I have received concerning the future of unleaded avgas is that there is a need for two grades of fuels, not just one.

Most pilots feel that there should be a new 100 octane unleaded fuel to replace 100LL and a second grade for either an auto fuel-based product or a 94-octane fuel based on just removing the lead from the current 100LL. (Swift Fuels already has a fuel, UL94, that meets ASTM D7457.)

In the 1990s, the man in charge of fuel requirements at Cessna, Cesar Gonzalez, felt that the future of general aviation — and especially sport aviation — rested on the availability of a non-boutique fuel derived from the readily available pool of automotive gasoline.

That led to the development of ASTM D6227, “Standard Specification for Grade 82 Unleaded Aviation Gasoline.”

While the spec had limits on ethanol and other oxygenates, it was basically just regular unleaded auto gas.

The spec was approved by ASTM, but I believe is not being used at this time.

I suggest the industry and regulators, including those involved in the Eliminate Aviation Gasoline Lead Emissions (EAGLE) initiative, work to get the 82UL spec active again.
Then the members of the General Aviation Manufacturers Association (GAMA) could approve the fuel for all 80/87 engines in the fleet, plus all of the sport aviation aircraft.

Next, the National Air Transportation Association (NATA) could encourage all FBOs and fuel distributors to make the fuel widely available.

Many FBOs already have the facilities to handle two grades of avgas, but others may need to add some equipment.

The big problem here is sourcing non-ethanol auto fuel. However, auto fuel containing ethanol cannot be shipped in pipelines. This means that non-ethanol fuels are available at all distribution facilities even if a state requires that all auto fuel contain ethanol.

Once 82UL becomes available and pilots become aware of it and know that it is approved for their aircraft without an STC, I believe that the sales and benefits will become very significant.

For example, the economic benefits for pilots will be very real. According to a recent Google search, the average price for 100LL in the US in early October 2023 was $6.93 per gallon. The estimates for one of the 100 octane unleaded fuels say it will cost between 50 cents and $1 more a gallon than 100LL.

However, the present price for regular unleaded auto fuel is about $4 a gallon vs $7.50 for an unleaded 100 fuel, saving pilots about $3.50 a gallon.

If a pilot flies 100 hours a year at 8 gallons an hour, that is a significant difference, especially for working class pilots who just want to go for a $100 hamburger and not a $200 hamburger.

There will be some additional costs with 82 UL fuel, such as handling and shipping, plus storage at dedicated facilities.

However, these can be offset by refunds of road taxes. If an auto fuel is sold for a non-road use, such as in aircraft, the state and federal road taxes can be refunded.

The bottom line
Approving 82UL is not the total answer and it is not the grandiose solution for all of GA’s unleaded fuel problems. But it will help ensure a continued supply of an approved, reasonably priced fuel for part of the GA fleet.

And it will significantly reduce the amount of lead being emitted into the atmosphere, which is one of the goals of the EAGLE program.
The other option is to do nothing and wait for a fully approved unleaded replacement for 100LL.

But based on past performance, how long will that take? And how will that affect the costs associated with flying a GA aircraft?

Take that one step further: How will that wait and uncertainty affect the number of people going into or even staying in flying?

 

NH Company Completes Autonomous Helicopter Flight Test Program
By Mark Phelps 
Published: November 8, 2023

Screenshot from Rotor Technologies' video of its autonomous flight-test program. A link to the video is included in the text of the article.

Nashua, New Hampshire-based Rotor Technologies announced yesterday (Nov. 7) it has completed a test campaign for its uncrewed R220Y, a derivative of the Robinson R22 piston-powered helicopter. Rotor, which self-describes as a developer of autonomous vertical takeoff and landing (VTOL) aircraft, claims theirs is the first-ever test program involving an uncrewed full-scale civilian helicopter. A video on the campaign is posted on the company website.

The flight test regime involved two examples of the R220Y autonomous helicopter. Modifications from the stock R22 include removing seats, pilot controls and instrument panels. All flight functions of the test helicopters were automated by Rotor’s technology, according to the announcement. The test regime included more than 20 hours of flight time and more than 80 hours of engine-run time.

According to the Rotor statement, “These flights successfully proved Rotor’s flight control systems, autonomous hover and velocity modes, and vision-based perception systems. The campaign also developed the aircraft’s long-distance flight capability through in-flight testing of long-range radio equipment and cellular LTE communication links—although all flights were conducted over a limited radius within direct line of sight of a ground control station.”

Rotor Founder and CEO Dr. Hector Xu said, “Our [artificial intelligence—AI] pilot system is already expert-level at tasks like precision flight control and navigation in poor visibility conditions, and we’re increasing its capabilities every day.” Robinson Helicopter is fully on board with the program. The California-based manufacturer’s VP of operations, David Smith, said, “We believe that our flight heritage and manufacturing capability will position Robinson to be a key player in the next generation of VTOL aviation.”

Rotor’s “next step” is developing its R550X, a similarly modified version of Robinson’s four-seat R44 Raven II. Rotor chief commercial officer Ben Frank said, “We’re taking all the technology that we’ve developed on the R220Y and are putting it on a similar—and even more capable—platform. We’re working with a set of close partners to put the R550X into revenue operation in 2024.”

The R550X is expected to have a payload capacity of 1,212 pounds and more than three hours’ endurance. Potential mission types for the autonomous helicopter include examples of the classic “three Ds” often targeted by developers of uncrewed aircraft—Dirty, Dangerous and Dull. They include firefighting, crop dusting, construction, humanitarian aid and remote cargo delivery.

Peering even further into the future, Rotor anticipates an eventual move into passenger operations for its autonomous aircraft. The company notes that a 200-mile, traffic-snarled journey (such as Boston to New York) could be accomplished in 90 minutes with its aircraft.

Rotor did not immediately return email and telephone requests from AVweb for further details on pricing, financing and production planning.


 


Lockheed Martin Jets into Nuclear Electrical Spacecraft Power
NOVEMBER 08, 2023

Note: See LOS ALAMOS NATIONAL LABORATORY’S CONCEPT OF A SPACE NUCLEAR REACTOR SYSTEM TO PRODUCE HIGH-POWER ELECTRICITY. IMAGE CREDIT: LANL in the original article.

Hot off the heels of the DRACO announcement in July 2023, Lockheed Martin was awarded $33.7 million from the Air Force Research Laboratory (AFRL) for the Joint Emergent Technology Supplying On-Orbit Nuclear (JETSON) High Power program to mature high-power nuclear electric power and propulsion technologies and spacecraft design. The JETSON effort is now in the preliminary design review stage, with the option to go to critical design review level.

With Space Nuclear Power Corp (SpaceNukes) and BWX Technologies, Inc. (BWXT) as our partners – both of whom carry deep expertise in nuclear power and reactor design – our JETSON team will address the escalating need for advanced spacecraft mobility, situational awareness, and power generation that far surpasses traditional spacecraft capabilities. Providing both on-board electrical power and the ability to power electric propulsion Hall thrusters used on Lockheed Martin’s LM2100 satellites, JETSON serves as a critical step forward in using nuclear electric propulsion to get humans to the Moon, Mars and beyond.

“Nuclear fission development for space applications is key to introducing technologies that could dramatically change how we move and explore in the vastness of space,” said Barry Miles, JETSON program manager and principal investigator, at Lockheed Martin. “From high-power electrical subsystem and electric propulsion, to nuclear thermal propulsion or fission surface power, Lockheed Martin is focused on developing these systems with our important government agencies and industry partners.”
 
Nuts and Bolts
 JETSON will use a fission reactor that generates heat, which is then transferred to Stirling engines to produce between 6 kWe and 20 kWe of electricity – four times the power of conventional solar arrays without the need to be in continuous sunlight. The reactor draws heavily from the design and lessons of the 2018 Kilopower Reactor Using Stirling Technology (KRUSTY) demonstration led by NASA and the DoE’s National Nuclear Security Administration.

“A future JETSON flight experiment will enhance maneuver and power capabilities shaping future space force operations,” said Andy Phelps, CEO of SpaceNukes. “The United States has not flown a reactor in space since 1965. As the first novel reactor tested in more than 50 years, we’re giving our country a technical leap – both terrestrially and on-orbit – as well as the ability to expand future space exploration.”

This technology has the potential to produce much higher electrical output than spacecraft powered by solar panels, which generally garner about 600 watts of power, or the equivalent of six lightbulbs. For deep space exploration missions not as close to the sun, or in shadowed regions, nuclear electric-powered subsystems are a great alternative to have in a company’s power-generation toolkit.
 
Safety First
 As on other space nuclear programs, safety is a top priority with JETSON. Uranium, prior to the start of the fission process, is benign. During launch, the reactor is in an inert, inactive configuration and is designed to not turn on and start the fission process until the spacecraft is in a safe non-decaying orbit far out from Earth.

“BWXT’s support as the nuclear manufacturer on the JETSON program complements Lockheed Martin’s heritage space flight capabilities and SpaceNukes’ nuclear design expertise,” said Joe Miller, BWXT Advanced Technologies LLC president. “Building upon the KRUSTY demonstration, BWXT investment and unique infrastructure, the team is well-positioned to deliver and fly a space nuclear system under the JETSON program.”

The development work will be done across the country including at Lockheed Martin’s facility near Denver, at AFRL’s facility in Albuquerque, New Mexico, at SpaceNukes’ facility at Los Alamos, New Mexico and at BWXT in Lynchburg, Virginia. Several New Mexico-based national labs, facilities and suppliers will also support.


 


Russian manufacturer test-flies prototype widebody passenger airplane
By Barry Neild and Anna Chernova, CNN

Updated 12:07 PM EST, Wed November 8, 2023

The United Aircraft Corporation said its prototype passenger plane can carry up to 370 people. United Aircraft Corporation CNN — 

Russia’s leading aircraft manufacturer says it’s completed a successful test flight of a new widebody passenger airplane that it claims could replace Western aircraft in the country’s skies. 

The United Aircraft Corporation said a prototype of its IL-96-400M long-haul airplane has taken off for the first time on a flight that lasted 26 minutes and reached altitudes of up to 2,000 meters (6,562 feet) and speeds of up to 390 kilometers per hour (242 mph), according to a news release posted by the company last week.
UAC, which oversees Russian aviation brands including Tupolev, Ilyushin and Sukhoi, said the plane will be capable of carrying up to 370 passengers, a capacity that would put it alongside the likes of Airbus’ A340 or Boeing’s 777.

It said the airplane marked a step up from the previous IL-96-300 aircraft, production of which reportedly halted more than a decade ago because it was unable to compete with Western models.

“The first and successful flight of the modernized IL-96-400M is a demonstration of the highest level of competence of domestic aircraft manufacturers,” Russia’s deputy prime minister, Denis Manturov, said in the release.

According to UAC, the IL-96-400M can be configured in up to three passenger classes and will be installed with a “modern infotainment system” offering internet, TV and satellite communications. It will also be equipped with a “modern” kitchen.

Transatlantic airplanes are flying at the ‘speed of sound’ right now. Here’s why
The new airplane, which was photographed midair decorated in UAC corporate colors, could be seen as a public relations win for Russia at a time when its domestic aviation industry is creaking under pressure of Western sanctions imposed because of its invasion of Ukraine.

US and European sanctions on leasing planes to Russia led to that country losing nearly 10% of commercial aircraft before President Vladimir Putin enacted laws allowing Russian airlines to seize leased aircraft and re-register them domestically.
But with limited access to parts for planes made by Boeing, Airbus and other Western manufacturers like Bombardier and Embraer, experts say keeping fleets airworthy will be increasingly difficult. As of 2022, only 144 active Russian airline planes were built in Russia, according to data provided by aviation analytics firm Cirium.

“Although Moscow won’t admit it, the sanctions that followed the Ukraine invasion have really damaged Russian aviation,” Murdo Morrison, head of strategic content at FlightGlobal, tells CNN.

‘Massive gamble’
“The problem is that lack of spares – some get in through the back door undoubtedly – means that many Airbus and Boeing aircraft flying in Russia today are potentially dangerous. Although Russia has a proficient regulator, there is very little visibility as to the health of its fleet.”
In September, an Airbus A320 operated by Ural Airlines, reportedly one of the leased aircraft appropriated by Russia, was forced to make an emergency landing in a field in Russia’s Novosibirsk region due to what was provisionally claimed to have been a midair failure of its hydraulic system.
What it was like to pilot the supersonic Concorde jet
Last year, a safety audit by the International Civil Aviation Organization resulted in Russia being marked with a “red flag” indicating insufficient regulatory oversight – a status shared by only three other countries – Bhutan, Congo and Liberia.

Addressing concerns, Russia’s Ministry of Transport said at the time that flight safety on Russia-operated aircraft meets international standards.

UAC’s release said the new IL-96-400M’s safety and reliability was comparable to the “world’s best models due to the redundancy of the aircraft’s systems and its aerodynamic configuration.”

The manufacturer also said it would meet international regulatory requirements.
Yuri Slyusar, UAC’s general director, was quoted in the release saying it would, alongside other Russian-built aircraft, be deployed across the country’s aviation network and “replace foreign analogues.”

FlightGlobal’s Morrison says that while the aircraft may be reliable, they will be significantly inferior to their Western counterparts and are unlikely to be manufactured in the quantities once seen under Soviet rule.

“Trying to restore Russia’s pre-1990 aerospace industry is a massive gamble. In fact, it will lose the state billions, although Moscow probably accepts that the political price is worth paying, and, besides, it hasn’t any choice.”


 


Smaller, Lighter Cessna 327 ‘Mini Skymaster’ (Back in the Day)
The 327 was Cessna’s solution to a downsizing opportunity. Then it ended up in a NASA wind tunnel.
By Jason McDowell

June 27, 2023

A close-up shot of the 327 undergoing testing in NASA’s Langley Research Center in Hampton, Virginia. [Credit: NASA]

Once upon a time, GA aircraft manufacturers pursued market niches with the ferocity of wild dingos. When marketing teams identified a potentially underserved customer segment, they wasted no time introducing minor variations to existing models to accommodate it. Compared to today’s offerings, the resulting variety of aircraft was spectacularly broad and varied.

When Cessna determined some customers would be willing to pay a bit more for a slightly more powerful 172, for example, the company introduced the 175 Skylark. This was little more than a 172 with a different engine, but the company was in pursuit of new market segments and opted to advertise it as an entirely different model.

Similarly, Beechcraft identified markets for both full-sized and smaller light twins in the forms of the Baron and Travel Air. With four seats instead of five or six, thriftier 4-cylinder engines, and significantly lighter weight, the Travel Air was presented as a simpler, more compact solution that emphasized economy rather than outright performance.

One of the few publicly available photos of the Cessna 327 prior to its time with NASA. In this view, the compact fuselage, sleek windscreen, and lack of wing struts are evident. [Credit: Cessna] 

Fresh off the successful launch of the unique, twin-boom Skymaster, Cessna began exploring the same opportunity in 1965. Recognizing the market might have room for a smaller, lighter version of the Skymaster, it built a single prototype of the Cessna 327. While it was never given an official name, various sources use the nicknames “Baby Skymaster” and “Mini Skymaster.”

The rationale behind this model was likely rooted in findings shared by other manufacturers—that many owners and operators of twin-engine aircraft travel alone or with only one passenger most of the time. For these customers, it made little sense to haul around excess seats and cabin space while burning additional fuel and paying more to maintain larger, 6-cylinder engines. The diminutive Wing Derringer was an extreme example of minimalist light twins. 

The 327 was Cessna’s solution to this downsizing opportunity. Essentially a 172-sized Skymaster, it was both smaller and lighter than the larger centerline twin. Equipped with two 4-cylinder, 160 hp IO-320 engines, it utilized Cessna’s strutless, cantilever wing, and raked windscreen, similar in design to the 177 Cardinal series. 

A three-view diagram of the Cessna 327 reveals its blend of Skymaster layout with Cardinal design. [Credit: NASA]

The smaller size and sleek lines gave the 327 a sporty look compared with the more utilitarian Skymaster. But like the Skymaster, the front seats were positioned well ahead of the wing’s leading edge. Combined with the lack of wing struts, this would have provided outstanding outward visibility and positioned the 327 to be a favorite for aerial photography.

Cessna never published any dimensions or performance specifications for the 327. Using comparable light twins with the same engines as a reference, we can predict the 327 likely would have had a maximum takeoff weight of 3,500-4,000 pounds, with a maximum cruise speed of 150-175 mph. Fuel burn would also have been correspondingly lower, roughly on par with a Piper Twin Comanche with similar engines.  

First flight took place in December 1967, and Cessna flew the 327 until the following year, logging just less than 40 hours of test flights. At that time, the airplane was presumably placed into storage, and the registration—N3769C—was canceled in February 1972. But unlike many other prototypes, the 327 would serve one last purpose before vanishing forever.

With the front propeller removed, NASA studied various configurations of propellers and shrouds to learn more about propeller noise and efficiency. [Credit: NASA]

The airplane’s final role would be filled at NASA’s Langley Research Center. There, it was used in the full-scale wind tunnel, or FST, for noise-reduction studies. This research was conducted by Cessna, NASA, and Hamilton Standard in 1975 to evaluate various propeller and propeller shroud designs.

The NASA team removed the front propeller and fitted the 327 with an assortment of three-blade and five-blade options housed within a custom-built shroud. Perhaps surprisingly, the shroud was found to actually increase propeller noise slightly as opposed to reducing it as expected. The airplane was later fitted with Hamilton Standard’s experimental “Q-Fan,” a ducted fan design that was touted to transition from full forward thrust to full reverse thrust in less than one second. 

No official record exists outlining the 327’s ultimate fate. The apparent lack of any information beyond the 1975 wind tunnel testing suggests the airplane was scrapped after that. This was perhaps part of a contractual agreement with Cessna, as the company was known to have discarded other prototypes during that era.

We’re left with a smattering of photos and a few piles of technical reports. 
Coincidentally, with the introduction of electric vertical takeoff and landing vehicles and a renewed interest in noise-reduction technologies in the GA sector, the studies might prove valuable even today. And for that matter, a compact, efficient piston twin with the safety of centerline thrust might as well.


 


Boeing Outlines 777-9 Certification Test Plan
Guy Norris 
November 12, 2023

Credit: Tony Osborne/Aviation Week

DUBAI—Amid growing hopes of beginning the long-delayed certification effort for its 777-9 flagship, Boeing is providing initial details of how the process will be structured.

The 777-9, which is making its second appearance at the Dubai Airshow, is targeted at entry-into-service in 2025 having endured several sizable delays. Issues during early flight trials and increased regulatory scrutiny have held back type inspection authorization (TIA) from the FAA—a move that will mark the formal start of certification.

Although the FAA will not grant TIA until it is confident the airplane is ready and Boeing has addressed all design and system safety assurance questions, Boeing Commercial Airplanes President Stan Deal tells Aviation Week that the milestone is approaching. “I anticipate shortly we’ll be at the first phase of type inspection authorization on the airplane and getting the FAA and eventually [the European Union Aviation agency] on for score for all those test cards we’ve been flying,” Deal says.

“We’re over 1,100 flights on the program already and 3,200 [flight] hours, so we’ve we put more time on this airframe and engine combination than any other airplane in history [in terms of Boeing pre-certification flight tests]. The performance is looking good in terms of the fuel burn and system functionality,” Deal says.

“It’s super exciting that we're getting to that point in the program,” says Heather Ross, project pilot for the 777X and lead pilot for WH001, the first development aircraft which is in the flight display here at Dubai. The aircraft was used earlier this year to complete company testing of takeoff performance and velocity minimum unstick (VMU) evaluations, a campaign which determines the minimum takeoff speeds for a new aircraft.

“VMU testing was a big step. We also completed some brake testing—we've got a little bit more tuning to go but that's all kind of progressing at pace. We've also got some other stability and control (S&C) testing as we evolve the flight control laws and as we make some changes we’ll go out and re-do that phase,” she adds. “The whole program is involved in focusing on trying to get some of those safety assessment reviews completed and the paperwork closed out so that we can document it—then we can work through completing the remaining items before TIA.”

While the additional S&C work will be undertaken by the second test aircraft, WH002, the brunt of the certification effort will be performed by the third test aircraft, WH003, which originally joined the program in August 2020. “That is really our engine and steady state performance airplane,” Ross says. “They're getting ready, and they'll be the first up when we do get TIA because that's the majority of the work that the initial certification is going to take place on. So they’re getting spooled up ready to go.”

“WH003 has got propulsion testing, so they’re going to have the most up-to-date software and hardware on that airplane, so they'll be first in the barrel as it were for the certification effort,” Ross adds. The aircraft will be configured with the production standard GE9X engine with an updated combustor liner, which has been upgraded to counter issues encountered a year ago. “One engine issue we found through the test program on the combustor liner, which GE Aerospace has got well in hand,” Deal adds.

The third aircraft has been used primarily to evaluate flight loads and performance of the auxiliary power unit, avionics and the GE9X engines. WH001, which first flew in January 2020, has taken the lead in testing S&C as well as high and low-speed aerodynamics. It has also been used for avionics, flight control systems and brake tests. The second aircraft—the entry of which into the program was also delayed until April 2020 by coronavirus-related precautions—was mainly targeted at autoland system work as well as ground effects testing.

A fourth aircraft, WH004, which is currently stored, incorporates a production-representative cabin configuration, and will ultimately finish its test role with a phase of extended twin-engine operations (ETOPS) and airline-like functionality and reliability operations testing.


 

World’s Biggest Aircraft Makes Its Ground Debut
Lighter Than Air's massive zeppelin-like airship is now undergoing outdoor operations testing in Mountain View, California.

By Adrianna Nine November 9, 2023

Credit: LTA Research

NASA alumnus Alan Weston and Google co-founder Sergey Brin have been working on something big. The duo have spent the last decade designing, testing, and building support for Pathfinder 1, an experimental hybrid airship longer than three Boeing 737s strung together. Now, the fruit of their labor is finally emerging from its supersized hangar to make its ground debut in Mountain View, California, where the airship will undergo outdoor flight operations testing before attempting its first real flight. 

At 124.5 meters (408 feet) long, Pathfinder 1 is already the largest aircraft the world has seen since 1930. It looks a lot like a blimp or a zeppelin, both of which traditionally leverage lighter-than-air gas to lift into the air. This appears to be what inspired Weston when he named his company Lighter Than Air Research (LTA). 
Pathfinder 1’s twelve Pipistrel electric motors—powered by two 150-kilowatt diesel generators and 24 battery packs—will propel the aircraft, swiveling from positive 180 degrees to negative 180 degrees and working alongside four fin rudders for directional control. Meanwhile, the nylon-based helium bags in Pathfinder 1’s inner walls will lend lift and buoyancy.

Credit: LTA Research

All of this is held in by the aircraft’s laminated Tedlar exterior. Pathfinder 1’s skeleton consists of 13 circular mainframes, each consisting of 3,000 welded titanium hubs and 10,000 polymer tubes reinforced with carbon fiber. These protect Pathfinder 1’s helium bags, while an understated nose cone helps the airship withstand winds up to 80 miles per hour, or 70 knots. 

It’ll be a while before Pathfinder 1 reaches that type of speed, though. Wednesday’s slow roll out of the hangar was just one baby step out of many when testing the aircraft. On the ground, the LTA team will see how the warmth brought about by sunrise affects the airship’s one million cubic feet of helium. And when Pathfinder 1 finally lifts off, it’ll only be a few feet off the ground. A mobile mast will ensure the airship doesn’t go anywhere before it’s ready. 

The idea is for Pathfinder 1 to forge a new path for sustainable air travel. (This is what ultimately earned LTA more than $100 million in funding from Brin, whose philanthropy largely focuses on climate change and public health.) It goes without saying that passenger or cargo flights are a long way off, though. LTA has until September 2024 to take advantage of a Federal Aviation Administration (FAA) airworthiness certificate, which grants the company permission to complete up to 50 test flights under 1,500 feet.


 


B-21 Takes To The Sky For The First Time As Flight Testing Begins
Brian Everstine November 10, 2023
B-21 Raider first flight. Credit: Matt Hartman

The U.S. Air Force’s next-generation bomber has flown for the first time.

The Northrop Grumman B-21 Raider took to the skies over the company’s Plant 42 facility in Palmdale, California, on Nov. 10—less than one year since its first public rollout. Videos of the flight circulating on social media show the bomber and a chase plane flying over the flightline.

“The B-21 Raider is in flight testing,” Air Force spokesperson Ann Stefanek tells Aerospace DAILY. “Flight testing is a critical step in the test campaign managed by the Air Force Test Center and 412th Test Wing’s B-21 Combined Test Force to provide survivable, long-range, penetrating strike capabilities to deter aggression and strategic attacks against the U.S., allies and partners.”

The flight testing comes less than a month after the B-21 was spotted conducting taxi tests in the daylight at Palmdale. The first aircraft will now move to Edwards AFB, California, for developmental testing.

The video confirms the flying-wing aircraft has a simple W-shape trailing edge and reveals an extremely clean design with an almost featureless underside. The deeper centerbody compared to the B-2 is evident, with the undersurface between the main and nose gear essentially flat. The cambered leading edges also are evident, as are the trailing-edge control surfaces, including the outer split surface drag rudders.

In a statement, the Air Force says the program is in the engineering and manufacturing development phase and is on track to deliver aircraft to Ellsworth AFB, South Dakota, in the mid-2020s.

Six aircraft are in production now. The test aircraft are being built on the same production line using the same tooling as upcoming production aircraft.

The flight test comes as the Air Force and Northrop Grumman officials had been tight-lipped about specific test milestones. A first flight is required for the Air Force to award Northrop Grumman its first low-rate production contract.

“The robust flight test campaign is being executed by a Combined Test Force comprised of Northrop Grumman and Air Force personnel that will validate our digital models and moves us another step closer to reaching operational capability,” the company said in a statement.


 


BETA continues rollout of electric aircraft charging network with Archer Aviation as customer
Scooter Doll
 | Nov 7 2023 - 8:59 am PT

Two of the more prominent developers in electric aircraft – BETA Technologies and Archer Aviation have announced they are collaborating to help roll out an interoperable charging network to support a multitude of electric vehicles.
If you follow any of our eVTOL coverage, you probably recognize both Archer Aviation ($ACHR) and BETA Technologies, as both electric aircraft and charging developers have hit some major milestones in the past year.

For example, Archer completed its maiden flight with its Midnight eVTOL last month, ahead of commercial air taxi operations in the United Arab Emirates (UAE) slotted for 2025.

BETA’s ALIA electric conventional takeoff and landing (eCTOL) aircraft completed a flight milestone of its own in October, traveling 2,000 miles from the company’s headquarters in Vermont, across 12 states down to Florida, where the US Air Force is now validating its vital use cases like critical resupply, cargo deliveries, and personnel transport.

In addition to eVTOL and eCTOL aircraft, BETA Technologies also develops its own charging technology and already has 14 stations online in the US, with 55 additional sites already in development or construction.

Through today’s latest collaboration, Archer intends to implement BETA’s electric aircraft charging technology to support its own eVTOL lineup, helping grow a universal network for all zero-emissions vehicles.

BETA Technologies’ Charge Cube system / Credit: Business Wire

Archer adopts BETA’s electric aircraft charging and beyond
The electric aircraft and charging developers shared a joint release today, outlining what they are hailing as an “industry-first agreement” to roll out an interoperable fast-charging network across the zero-emissions aviation segment.

The collaboration comes after the General Aviation Manufacturers Association (GAMA) published a report in September titled “Interoperability of Electric Charging Infrastructure,” concluding that shared charging infrastructure offers numerous benefits over multiple proprietary protocols developed by OEMs. We’re seeing something similar happen in the North American passenger EV market as OEMs are gravitating toward NACS.

To date, all of BETA’s charging infrastructure has lined the East Coast, but following its collaboration with Archer, electric aircraft charging is moving west. To begin, Archer will implement two of BETA’s Charge Cube systems (seen above) at its test facilities in California, as well as multiple Mini Cube mobile chargers deployed as needed. Archer’s SVP of powertrain, Dr. Michael Schwekutsch, spoke to the collaboration with BETA and what it means for the future of the industry:
During my time as the VP of Powertrain Engineering at Tesla it was well understood that having a widely accessible, fast-charger network was key to driving the adoption of EVs, and the same is true for eVTOLs, and that’s why we are so excited to collaborate with BETA to build out the charging network for our electric air taxis.
This industry-first agreement shows excellent foresight from both companies, especially BETA Technologies, which has been developing electric aircraft charging technology for years in anticipation of a new widespread mobility segment. BETA founder and CEO Kyle Clark elaborated:
Over the past decade, transportation has shifted toward electric and now we’re seeing resonance and viability for aviation to do the same. A backbone of reliable, fast and accessible infrastructure will be critical to enabling this technology, which is why we’ve been focused on building out a charging network alongside our aircraft for some time now. When we designed our chargers, we saw an opportunity to support the entire sector by using an already peer reviewed standard, and we’re thrilled to collaborate with Archer now to validate that aim.
Looking ahead, BETA Technologies will continue working to install its charging infrastructure around the US, which now includes the systems at Archer’s facilities mentioned above.


 


Curt Lewis