June 21, 2023 - No. 025

 


In This Issue 

: Boeing Jump-Starts 737 MAX Angle-Of-Attack System Retrofits

: NTSB Safety Reminder: Danger of Diesel Exhaust Fluid (DEF) Jet Fuel Contamination Remains a Serious Safety Concern 

: Manufacturing defect prompts FAA to issue AD for LEAP 1-A engine used on A320neo 

: Emergency Egress System Unveiled by Airframe Innovations For Cessna 206 

: FAA will require secondary cockpit barriers for new planes; ex-FAA special agent says majority of aircrafts ‘still vulnerable to a 9/11 style attack’

: Rolls-Royce Says UltraFan ‘Bristling’ with New Technology

: How RISE Arose: The Story Behind Decades of Innovations That Bring CFM to a Pivotal Moment

 


Boeing Jump-Starts 737 MAX Angle-Of-Attack System Retrofits
Sean Broderick June 18, 2023

LE BOURGET—Boeing is getting a head start on retrofitting the 737 MAX fleet with an additional angle-of-attack monitoring system by rolling out new aircraft with the needed wiring in place and preparing a service bulletin for operators to use on in-service airframes.

"All the airplanes we are building now are pre-wired," 737 Customer Leader Bob Michael told ShowNews on June 18 at the Paris Air Show. "We actually started to install the wiring on production [aircraft] last summer."

The enhanced angle of attack (eAOA)—required by the European Union Aviation Safety Agency (EASA) as part of agreeing to the 737 MAX's return to service following fatal accidents in 2018 and 2019 and its subsequent grounding—provides a third source of AOA data. It uses five software monitors embedded into existing hardware to track data from the aircraft's two physical AOA sensors, explained Boeing 737 MAX Chief Pilot Justin Carlson. Any abnormalities are detected and flagged, and the malfunctioning AOA sensor is removed. 

"All of that happens automatically," Carlson said.

The system also includes new switches that allow pilots to disable nuisance alerts triggered by a malfunctioning AOA. The new monitoring is designed to do this, but the switches serve as a backup, Carlson said.

Boeing has agreed to roll out the entire package of changes on the rest of the 737 MAX fleet within three years once it gets certified on the 737-10. Ideally, the work will be done during scheduled heavy maintenance visits.

"There's a fair amount of wiring that has to be added in the flight deck and in the [electronic equipment] bay," Michael said.

The company is working on a service bulletin that operators can use to pre-wire their 737 MAXs. It is expected to be released by yearend. Once the 737-10 is certified, a second service bulletin will detail the entire upgrade. Boeing's latest plan includes FAA approval in 2024.


 


 

 


NATIONAL TRANSPORTATION SAFETY BOARD UPDATE



 NTSB Safety Reminder: Danger of Diesel Exhaust Fluid (DEF) Jet Fuel Contamination Remains a Serious Safety Concern 

The danger of contamination of jet fuel by diesel exhaust fluid (DEF) remains a serious safety concern. Recently, the Federal Aviation Administration (FAA) revised a safety alert for operators advising operators to inform the fueler after discovering Diesel Exhaust Fluid (DEF)-contaminated fuel and contact their original equipment manufacturer to develop inspection techniques and maintenance actions appropriate for each specific aircraft model type. 
 
Put safety first and read the NTSB 2019 Safety Alert (SA-079) warning jet fuel providers to take measures to prevent contamination of jet fuel by DEF. Aviation fuel contamination of all types is a longstanding safety issue and inadvertent introduction of DEF into aviation fuel continues to be a safety issue. The NTSB wants fuel providers to ensure they store all chemicals in labeled containers and that they add a “NOT FOR AVIATION USE” label to all DEF containers.


 


Manufacturing defect prompts FAA to issue AD for LEAP 1-A engine used on A320neo
BY RYTIS BERESNEVICIUS
2023-05-22

The United States Federal Aviation Administration (FAA) issued an airworthiness directive (AD) relating to all CFM International LEAP 1-A engines, which are used exclusively on the Airbus A320neo family of aircraft. 

The FAA said it was prompted to issue the AD following the discovery of certain parts of the engine being manufactured with materials with reduced properties due to iron inclusion. The list of parts includes certain high-pressure turbine (HPT) rotor stage 1 disks (HPT stage 1 disks), forward outer seals, and compressor rotor stages 6–10 spools of the LEAP 1-A engines. 

CFM International, a joint venture between General Electric and Safran Aircraft Engines, made the initial discovery that “iron inclusion was detected in three non-LEAP–1A HPT rotor disks,” read the AD. However, further analysis by the manufacturer showed that “the iron inclusion is attributed to deficiencies in the manufacturing process” and affects more parts.  

The FAA warned that the reduced material properties of the HPT stage 1 disks, forward outer seals, and compressor rotor stages 6-10 spools could have “lower fatigue life capability due to iron inclusion, which may cause premature fracture and subsequent uncontained failure” of the components.  

To address the problem the FAA has ordered operators to replace the three affected parts, which affects 38 engines installed on aircraft registered in the US. According to the agency’s estimates, replacing the HPT stage 1 disk (a total of 38 affected parts) will cost $216,315 per product ($680 labor and $215,635 in parts), the forward outer seal (24 affected parts) $48,180 per engine ($680 labor and $47,500 in parts), and the compressor rotor stages 6-10 spool (15 affected parts) will set back operators $38,340 per engine ($680 labor and $37,660 in parts). 
All costs related to parts were estimated on a pro-rated basis. 

The effective date of the AD, which was issued on May 19, 2023, is June 23, 2023. 
The CFM International LEAP 1-A is one of two engine options available to Airbus A320neo aircraft family operators. Airlines can also choose to power their A320neo aircraft with the Pratt & Whitney PW1100G, which has experienced several supply chain issues, forcing carriers to ground their aircraft and search for wet lease alternatives. 


 


Emergency Egress System Unveiled by Airframe Innovations For Cessna 206
June 16, 2023 in Aviation News, International Aviation News, News, USA Aviation News

Note: See photographs in the original article.

UNITED STATES- Airframe Innovations Inc, based in Fairbanks, Alaska, has developed the PDQ Emergency Egress System for Cessna 206 aircraft. It is a straightforward and efficient solution that enables swift egress for the rear occupants of the aircraft.

As a Federal Aviation Administration (FAA) Parts Manufacturer Approval facility, the company has successfully addressed a longstanding design limitation in the Cessna 206 aircraft using its expertise in engineering and design.

Airframe Innovations has highlighted a significant design challenge in the Cessna 206. Deploying the flaps during landing creates an obstruction in the rear passenger door, which impedes the rapid exit of occupants during emergencies.

Aircraft equipped with floats particularly experience this issue critically in water-related emergency scenarios.

Photo: Airframe Innovations Inc., Examining how the flap obstructs the forward door on the 206.
The PDQ Emergency Egress System Specifications
Airframe Innovations has developed the PDQ Emergency Egress System to address the 206 egress issue. The design of this system comes with fail-safes that can withstand in-flight uncertainties. As well as comply with airport security protocols, providing a dependable solution to the problem.

If the alignment of both the Forward door hinges is proper, then the system installation is simple, according to the company. The transition from two hinge pins to a single hinge pin assembly allows for the completion of the installation process within approximately one to two hours.

All of the system’s exterior components use Stainless Steel Construction. Despite its durability, the entire system weighs only two pounds. Its less weight ensures minimal impact on the overall weight distribution of the aircraft.

Photo: Airframe Innovations Inc., The PDQ Emergency Egress System from the outside, showing the hinge pin assembly.
Testing of The System
In close collaboration with the FAA, Airframe Innovations conducted extensive testing. The testing ensured that the emergency exit door release located in the interior of the rear door is incapable of accidental activation during flight.

After conducting numerous testing scenarios using the actual equipment, Airframe Innovations concluded that the system’s mechanical fail-safes, inherent in its design, require intentional actions in the correct sequence to release the door, following the provided operating instructions.

The company emphasizes that pulling the red handle alone does not detach the door when it is in the “in-flight locked” position. Attempting to pull the red handle on a locked door will prove exceedingly challenging.

Photo: Airframe Innovations Inc., The interior handle. The emergency exit placard provides a layer of safety as it is clearly marked for emergency use only and is photoluminescent to aid in locating the handle in the dark. ….Note the clear protective cover, which adds another layer of safety.

Approval Type & Compatibility of The System
Airframe Innovations confirmed that the system has obtained Supplemental Type Certificate (STC) approval for installation in Canada and the U.S. Importantly, no modifications are necessary for the door.

The fuselage wall installation includes the installation of a base plate, along with a small hole to accommodate the shaft.

This design ensures compatibility with the current Cessna Service Manual and provides the flexibility of seat placement without any STC-imposed restrictions, according to Airframe Innovations.

Airframe Innovations confirmed that the current Supplemental Type Certificate (STC) extends to various models. Including the 206, U206, U206A, U206B, U206C, U206D, U206E, U206F, U206G, TU206A, TU206B, TU206C, TU206D, TU206E, TU206F, TU206G, 206H, and T206H.

Regarding system availability, Airframe Innovations noted that stock availability determines immediate shipping for in-stock items. The out-of-stock items have a lead time of one week.

While the system has received approval from Transport Canada (TC). Airframe Innovations is still awaiting TC’s Alternative Means of Compliance (AMOC) document. This document will serve as an exemption for operators from Airworthiness Directive CF-2020-10.\

The Egress Door Deposit option implementation for Canadian customers by Airframe Innovations. Once the Alternative Means of Compliance (AMOC) is issued, it secures their kit for shipment.

Canadian customers are not prohibited from installing the system. The company has disclosed that it has been waiting for TC to issue the AMOC since May 30, 2023. The latest update indicates that an individual has been assigned to complete the AMOC process.


 





FAA will require secondary cockpit barriers for new planes; ex-FAA special agent says majority of aircrafts ‘still vulnerable to a 9/11 style attack’

Boston Herald
June 14, 2023 at 3:30 p.m.

More than 20 years after 9/11, the FAA will require new commercial airplanes to have a secondary cockpit barrier to prevent attacks, but the feds will not mandate airlines to retrofit existing planes.

A retired FAA special agent tells the Herald that this means the vast majority of planes remain unprotected and are “still vulnerable to a 9/11 style attack.”

“It’s 22 years since 9/11, and the FAA is patting themselves on the back for putting secondary barriers on new aircraft down the road, while the aircraft we’re flying in now doesn’t have that protection,” the ex-agent Brian Sullivan added. “It’s ridiculous.”

The Federal Aviation Administration on Wednesday announced that it will require a secondary barrier on the flight deck of new commercial airplanes, helping protect flight decks from intrusion when the flight deck door is open.

A few months ago, the Herald reported about the continued need for secondary cockpit barriers in the wake of a Massachusetts man allegedly attacking a flight attendant while on a plane to Boston.
When a pilot has to exit the cockpit to use the bathroom, the “secondary barrier” becomes flight attendants standing in front of the cockpit entrance — usually with their push cart.
Secondary cockpit barriers are wire-mesh gates that would be located between the passenger cabin and cockpit door, blocking access to the flight deck while in the air.

“Every day, pilots and flight crews transport millions of Americans safely — and today we are taking another important step to make sure they have the physical protections they deserve,” U.S. Transportation Secretary Pete Buttigieg said in the FAA’s announcement.

Aircraft manufacturers are required to install secondary barriers on commercial aircraft produced after the rule goes into effect.

“No pilot should have to worry about an intrusion on the flight deck,” said Acting FAA Associate Administrator for Safety David Boulter.

The president of the Air Line Pilots Association called the FAA’s announcement on Wednesday long overdue. All existing aircraft should also have these barriers, added ALPA President Capt. Jason Ambrosi.

“With this action today addressing the installation of secondary barriers on newly manufactured aircraft, we must redouble our efforts to pass the Saracini Enhanced Aviation Safety Act (H.R. 911/S. 911) to address the retrofitting of existing airliners, and work to install primary barriers on cargo aircraft,” Ambrosi said.

“Because ensuring that no terrorist — domestic or international — breaches another aircraft flight deck door again should be one of this nation’s highest security priorities,” he added.

Installing secondary barriers on aircraft already in the fleet costs about $5,000 per aircraft or less, according to ALPA.

“Flight Attendants will no longer be forced to use their own bodies as the barrier between the cockpit and the cabin on new aircraft thanks to the finalized rule issued by the FAA today,” the Association of Flight Attendants-CWA wrote. “We support secondary barriers in all of our aircraft.”


 


Rolls-Royce Says UltraFan ‘Bristling’ with New Technology
by Aimee Turner
 - June 13, 2023, 5:27 AM

The Rolls-Royce UltraFan features an ultra-high bypass ratio and technology scaleable to a range of engine sizes and configurations. (Photo: Rolls-Royce)

Rolls-Royce chief technology officer Grazia Vittadini recently characterized the UltraFan engine architecture designed for ultra-high bypass ratios as “literally bristling with cutting-edge technologies from the front all the way to the back.” 

The company tested the UltraFan technology demonstrator at its Derby, UK site for the first time last month and will now put it through its paces in an effort to start developing a scaled range of engines. The manufacturer’s vision for UltraFan technology centers on a portfolio of two-shaft, three-shaft, direct-drive, and geared propulsion systems ranging in thrust from 25,000 to 110,000 pounds.

Designed to power new narrowbody and widebody aircraft entering service in the 2030s, Vittadini said the initial testing program would last several months, during which time the engine maker will carefully start integrating a host of technologies to help deliver a 10 percent efficiency improvement over the Trent XWB. 

The Rolls-Royce engineering executive told reporters that the regime would make purposefully slow and steady progress to support opening the engine’s operational envelope, which she admitted “at times [was] difficult.” Nevertheless, she insisted the team will make rapid progress. 

That begs the question: when will airframers be ready to present their airline customers with a new aircraft to exploit the benefit of such new engine technology? While Rolls-Royce goes to pains to stress that the UltraFan technology demonstrator not only heralds the engines of tomorrow but also helps improve the engines of today, the radical propulsion technology still awaits a similarly advanced airframe on which to showcase what Rolls calls a compelling clean-sheet advantage. “Dear airframers, give me an aircraft and you will have your engines,” said Vittadini, who has also served as Airbus’s chief technology officer and executive committee member.

Rolls-Royce director of aerospace technology and future programs Alan Newby told AIN that the manufacturer believes the industry needs such advanced technology to reach a state of readiness for future aircraft types.

“We talk to all airframers all the time, quite frankly,” he said. “We're in continual dialogue, not just with Boeing and Airbus, but with Embraer, with Gulfstream—all our customers. They're the ones that go to market and we work with them to determine what is the optimum time because it has to fit with their product strategy. We're just making sure we've got the technology ready when that time comes.”

At a time the development of electric- and hydrogen-powered aircraft steal headlines, Newby insists that gas turbine technology remains central to the engine maker’s development plans. “If you look at any projection out to 2050, you will see SAF, efficiency improvements, and possibly even hydrogen being featured,” he explained. “Yet 90 percent-plus of those applications will still need gas turbine engines in that part of the market that will burn the vast majority of the fuel. That is why we continue to innovate the gas turbine.

“What we're going to do under the EU Clean Aviation program is to take that a stage further,” he explained. “The obvious one is to push the bypass ratio higher, go for bigger fans that will require further advances in materials technologies, and then continue to develop the aerodynamics. We've done some work on aspects like shortening the inlet without damaging fan performance…so we'll continue to look at fan aerodynamics.”

Until the energy-density challenge for propulsion gets solved, engineers aim to help reduce an aircraft’s CO₂ footprint in an approach termed micro-hybridization, where instead of relying on the gas turbine to completely power the aircraft, electrical power can relieve the engine in certain operations.

“We've done some work on micro-hybridization in Bristol on one of our smaller engines where we've embedded electric starter generators,” said Newby. “That gives us the ability to take power off the shaft, but also allows us to put it back in. 

When you combine that with stored electrical power, you can use that to optimize performance around the flight envelope. So, for example, during certain transient conditions or during very low power conditions we could allow the engine to spool right down or, in arduous operating conditions, it could receive a slight boost of electric power.”

Newby added that Rolls believes it can exceed its stated 10 percent efficiency improvement “if you push all the way.”

“The hybridization [results in] probably a single-digit [improvement] but when you combine that with higher bypass ratios and so forth, then you'd be looking at probably going beyond 10 percent,” he concluded.


 


How RISE Arose: The Story Behind Decades of Innovations That Bring CFM to a Pivotal Moment
Jun 19 2023 | by GE Reports

Note: See photographs in the original article. 

In 1941, the United States government asked GE to develop the first American jet engine. Allied defense, industrial collaboration, technological advancement, and economic growth were at stake. GE delivered the very next year.

Now, more than 80 years later, GE Aerospace finds itself at the cusp of another era-defining moment. With climate change impacting communities and economies around the world, the aerospace industry is in the midst of what feels to some like a seismic shift.

To meet this challenge, CFM International, a 50-50 joint company between GE Aerospace and Safran Aircraft Engines, unveiled the Revolutionary Innovation for Sustainable Engines (RISE) program in 2021. The CFM RISE program aims to reduce fuel consumption and carbon dioxide emissions by more than 20% compared with today’s most efficient aircraft engines. Improved engine efficiency is key to helping the aviation industry achieve a larger target: net zero CO2 emissions by 2050.

In terms of sustainability, it’s a bold goal. But as Arjan Hegeman, GE Aerospace’s general manager of advanced technology, recently put it: “History will judge us to be on the right side of the fence.”Notwithstanding the urgency of the moment, the groundwork laid for the CFM RISE program has been decades in the making. 

Indeed, the innovations at the heart of the program — open-fan architecture, carbon-fiber composites, ceramic matrix composites, and additive technology — are the result of years of painstaking research, testing, and validation.One particular advancement that CFM RISE will utilize involves a variable-pitch engine design. 

Variable-pitch fan blades were first put into action in 1978 when GE teamed with NASA to develop the Quiet Clean Short-Haul Experimental Engine (QCSEE). The QCSEE had an unprecedented bypass ratio at the time of 11:1, meaning that for every unit of air that passed through the combustion chamber, 11 units bypassed the combustion process. (The bypass ratio describes the relationship between the thrust that the rotor, or fan, generates and how much energy it takes to drive the rotor.) At 11:1, the QCSEE was highly efficient.

The innovation at the heart of the RISE program is the open-fan architecture, also known as an “unducted fan,” which was first developed by GE and Safran in the 1980s. Open-fan technology derives its name from the absence of a case surrounding the fan. The architecture enables the engine to maintain the speed and performance of traditional turbofans while further increasing fuel efficiency and lowering carbon output. When the GE36, an experimental engine, debuted at the Farnborough International Airshow in 1988, it made a splash with its two sets of fully exposed, counter-rotating fan blades.

The CFM RISE program’s single-stage, variable-pitch demonstrator engine with stationary outlet guide vanes builds on the innovations GE Aerospace and Safran developed in the QCSEE and GE36 experimental engine programs. While the single set of variable-pitch fan blades rotate in front, a second set of outlet guide vanes help guide airflow.

Describing the work that GE Aerospace has done to take the technology even further in the RISE program, Hegeman points out that “our accuracy and capability of understanding how [an open-fan engine] works, and our optimization of the overall designs, have enabled us to go to a single-stage fan with stationary outlet guide vanes of a smaller diameter while meeting the performance target as well as the acoustics targets.”

The result is an open-fan engine with higher fuel efficiency, lower emissions, less noise, and turbofan flight speeds. “Bypass ratio is the name of the game,” Hegeman adds. “This is physics. It works. There’s no way you can ever get this level of efficiency in your fan when you put a duct around it.”

Despite realizing significant fuel savings, the GE36 fell victim to a dramatic drop in fuel prices in the late 1980s. While it never was put to use commercially, the technologies that engine pioneered helped chart the course of aviation for the next 30 years. Its carbon-fiber composite fan blades helped give birth to GE Aerospace’s higher-bypass jet engines, such as the GE90, the GEnx, and the GE9X. These, in turn, helped plane-makers build efficient, twin-engine long-haul jets like the Boeing 777, 787 Dreamliner, and 777X.

When the GE90 entered service in 1995, it became the first certified commercial jet engine to use lightweight carbon-fiber composite fan blades, which reduced weight and greatly increased fuel efficiency. Since then, GE jet engines have logged more than 200 million flight hours using composite fan blades. (Fast fact: The GE90-115B went on to set a Guinness World Record in 2002 by producing 127,900 pounds of thrust, making it the world’s most powerful commercial aircraft engine. It was only eclipsed in 2019, when the GE9X achieved 134,300 pounds on the test stand.)

But building a bigger and lighter fan isn’t the only way to make an engine more efficient. “Every time you make the fan a little bit bigger, you also add a little bit more drag” due to the bigger casing around the fan, Hegeman notes.

In addition to the open-fan design and carbon-fiber composite fan blades, the CFM RISE team is focused on improving the core of the engine, the section that holds the compressor, combustor, turbine, and other components that convert the fuel’s energy into efficient rotary motion. To do this, they’re using a groundbreaking material that has been tested inside both the CFM LEAP and GE9X engines: ceramic matrix composites. The CMC parts that GE Aerospace has developed over the past decade are one-third the weight of steel but can withstand temperatures as high as 2,400 degrees Fahrenheit, which is beyond the melting point of many advanced metallic superalloys.

When the CFM LEAP went into service in 2016, it marked the first use of CMCs and 3D-printed additive parts in the hot section of a commercial aircraft engine. These parts, which are lighter, stronger, and more heat-resistant and damage-tolerant than traditionally manufactured metal parts, helped make the LEAP 15% more fuel-efficient than its predecessors.

Taking a lead from LEAP, the engineers working on the RISE program are studying how to make a more compact engine core. Through another multimillion-dollar partnership with NASA, announced in late 2021, GE Aerospace has been awarded contracts to test and mature new jet engine core designs, including compressor, combustor, and high-pressure turbine technologies to improve thermal efficiency.

Last year, GE Aerospace teamed up with NASA again to test a megawatt-class, multi-kilovolt hybrid electric propulsion system in simulated high-altitude conditions (up to 45,000 feet) for the first time. GE Aerospace has spent more than a decade developing the hybrid electric system, building on its expertise in electric motors, generators, and power converters. The company will continue testing its hybrid electric system as part of NASA’s $260 million Electrified Powertrain Flight Demonstration (EPFD) project, with the aim of performing ground and flight tests by the mid-2020s. The CFM RISE program plans to incorporate this hybrid electric capability to optimize engine efficiency and lower CO2 emissions in its open-fan concept.

It’s important to remember what’s driving all of this marvelous engineering know-how: climate change. Single-aisle planes could make up 70% of the world’s rapidly growing commercial aviation fleet in the near future. And aviation currently accounts for roughly 2% of global CO2 emissions.

That explains the urgency as well as the excitement behind the CFM RISE program. “We are convinced that with climate change the cost of carbon emissions is going to make sure that the cost of fuel, whether it’s carbon-based, synthetic, biomass, or completely alternative fuels like hydrogen, is going to increase over time,” Hegeman says. “So, investing in fuel efficiencies is not only the right thing to do for the planet and for following generations, it’s also going to be much more of an economic differentiator for the operators compared to what it was in the past.”


Curt Lewis