Ground testing solutions based in Michigan

The programme company (GTS) shared it for testing

Composite materials for jet and helicopter engines

The design and manufacture of the capsule assembly.

Ground Test Solutions, Inc. (GTS), headquartered in Michigan

Manufacture of composite parts for test versions of aircraft engine pods

Motivators are used for pre-flight testing by manufacturers and after-sales testing by airlines.

Airplane engine nacelles-multi-component covers that house jet engines on airplanes-are typically made of composite materials. These are complex components that need to meet strict requirements such as temperature, fire resistance and noise damping.

However, before the engine is installed in the flight pod and placed on the aircraft, it must undergo a series of tests on the ground to ensure it can withstand the required temperature, altitude, bird strikes, and other conditions. Therefore, the test pod, similar to the flight pod but with slightly different requirements, is specifically designed to house the engine in a specially designed ground testing facility.

One of the few companies specializing in test pods is Ground Test Solutions (GTS), located in Grand Ledge, Michigan. GTS was founded 15 years ago by President Tom Hamel and Field Service Manager Mark Jeffreys. Both Hamel and Jeffreys previously worked at Pratt & Whitney, a company that produces aircraft engines and test engine pods.

GTS 26,000-square-foot facility employs about 40 people and produces bell mouth intakes, thrust reflectors, nozzles and plugs, sterns and complex pipes, all of which are composite-intensive products built for jet aircraft and helicopter test pods for pre-flight testing and aftermarket use.

According to Hamel, there are only three companies in the world that make aircraft test engine pods: GTS, Pratt & Whitney and Safran. 'Of course, GTS is the smallest so far,' he said. 'But we offer our customers the best value and the lowest cost.'

What are the differences between test pods and flight pods? GTS engineer Nick Dobson explained, 'Since it is only used for ground testing, the test pod does not need certain features, such as an external aerodynamic skin.'  'In other words, we built the test pod to match the weight and stiffness of a real flight pod, ensuring it meets the testing requirements.'

What kind of tests does the engine pod undergo? Dobson explained, 'Typically, customers place these devices in a soundproof test chamber to eliminate noise issues and undergo multiple testing cycles as specified by the Federal Aviation Administration (FAA).' These tests may include evaluating the pods overall durability and wear over time, its resistance to bird strikes, water sealing, high performance, and anti-icing capabilities. He added that the FAA sets specific testing requirements for engines before they enter service and retests them after several hours of flight to ensure they remain functional.

An example of a test chamber, with the white test pod in the middle.

Design test capsule

From design to manufacturing, it takes about a year to develop and produce each test pod. 'We design, we build the tools, we build,' Hamel said. 'Its all very vertically integrated.'

The design process begins with the design specifications provided by the engine manufacturer. Dobson explained, 'We receive the specific flow path shape, temperature, and pressure of the engine you are using.' GTS then uses Dassault Systemes SolidWorks to generate and analyze the CAD model of the pod, adjusting materials, lay-up plans, adhesives, and other factors based on the behavior simulated under temperature and pressure loads. Dobson added, 'We are indeed pushing the materials to their limits in terms of temperature and strength.'

The GTS then submits the design to the customer and makes adjustments as needed until the final design is finalized.

Complex tools and manufacturing

Next, the tool is designed and manufactured by itself, made of fiberglass or carbon fiber, or made from metal according to the needs of specific components.

The materials we use vary depending on the temperature requirements, Dobson noted. For a typical project, GTS occasionally uses fiberglass to construct the structure, although carbon fiber prepregs from Toray Industries are more commonly used. These prepregs are cut using a CNC cutting table at Gerber (Torrington, Connecticut, USA) and sandwiched with aluminum honeycombs in the lay-up. The structures are manually placed into custom-made open molds and then cured under vacuum bags in GTSs 24x20-foot oven. After curing, the parts are finished in a spray booth.

GTS also provides maintenance services for its equipment. 'If the composite is damaged or worn, we go to sites around the world to repair it,' Dobson said.

Most of the time and skill required to manufacture these components stem from the complexity of redesigning the pod components for non-flight engines. Hamel stated, 'All parts —— composite materials, latches, hinges, metal interfaces —— must be designed to mimic the weight and center of gravity of a flight pod, even if these parts differ slightly in their ground test designs.'  'Of course, all these designs must withstand more load than typical flight conditions, as they are designed to push the limits of testing.'

Most of the structure of the test pod is made of carbon fiber prepreg and

The honeycomb core is built and placed by hand on an open mold

It is then vacuum cured in an oven.

For example, one of the main components tested in the pod is the trumpet-shaped air intake (as shown in the left figure). Unlike the typical intake on a flight pod, this design features a trumpet-shaped expansion to more effectively draw air into the pod without generating the pressure and forces that occur during actual flight. Dobson explained, 'Laying prepregs in a honeycomb structure is a very complex curvature. For this purpose, we used Hexcels Flexcore honeycomb, which is designed to conform to curves.' He added that for a typical trumpet shape, about 8 to 20 layers of Toray CMA carbon fiber prepreg can be used on each side, with aluminum honeycomb sandwiched in between.

'The result is a very light, robust structure that is used to introduce air into the engine to measure important parameters of engine performance,' Dobson said.

Another complex component is the thrust reverser, known as an alternative thrust reverser in this context, since it does not generate actual thrust during ground tests. It surrounds the engines side. For example, one of the main components of the test cabin is the trumpet-shaped intake duct (as shown in the left figure). Unlike the intake ducts on typical aircraft cabins, the trumpet-shaped intake duct is designed with a flared mouth to more effectively draw air into the cabin without generating the forces produced by actual flight. Dobson explained, 'Laying the pre-impregnated fabric and honeycomb is a very complex curvature. For this purpose, we used Hexcels Flexcore honeycomb, which can be designed to wrap around curves.' He added that for a typical trumpet shape, about 8 to 20 layers of Toray carbon fiber prepreg can be used on each side, with aluminum honeycomb sandwiched in between.

'The result is a very light, robust structure that is used to introduce air into the engine to measure important parameters of engine performance,' Dobson said.

Another complex component is the thrust reverser, known as an alternative thrust reverser in this context, because it does not generate actual thrust during ground tests. —— It surrounds the engines side. Dobson noted, 'These are the most intricate structures we have built,' as they must be divided into two halves that can be opened like a clamshell to install and remove the engine for testing. The two halves are connected by specially designed metal hinges at the top and bottom.

Designing components that can withstand the required temperatures is also a challenge, especially for parts like the alternative thrust reverser and fairing that directly enclose the engine. Dobson said, 'We use the highest temperature carbon fiber prepreg we can find and add thermal shields and blankets where it gets very hot.' The fairing assembly is also designed with specific grooves and forks, which need to be equipped with measuring devices during testing.

Dobson added, 'We have significantly enhanced the capabilities of composite materials in terms of their application and usage, which led to extensive collaboration with Toray, our primary prepreg supplier. They have been able to conduct material tests for us, proving that these applications have sufficient strength and temperature resistance.' He noted, 'These are the most complex structures we have manufactured,' as they must be divided into two halves, which can be opened like a clamshell to install and remove the engine for testing. The two halves are connected through a specially designed metal hinge system at the top and bottom.

For test pods, the intake duct usually has a horn-shaped curve,

This makes it difficult to lay. The picture shows the placement in a clean room

The pod being prepared for solidification (below) and the LEAP 1B after painting

Test capsule (above).

Looking ahead: LEAP

GTS is one of two suppliers of the LEAP 1A and 1B test system to CFM International (Cincinnati, Ohio) for single-aisle aircraft such as the Boeing 737 MAX and Airbus A320neo series.

To that end, GTS is building after-sale test pods for sale to customers such as the FEDERAL Aviation Administration and airlines to test flight engines after use.

Dobson explained, 'These structures are highly complex, made from composite materials and metals.' Each cabins main horn opening, fairing, stern, and alternative thrust reverser are constructed using a layer of Toray 2510 carbon fiber 12K plain weave prepreg and a Flexcore honeycomb core, manufactured in a carbon fiber composite mold to match the thermal expansion coefficient.

Dobson added: 'LEAP is exciting for us

Its an ambitious project. Were going to build 30 to 40 capsules over the next 10 years.' ------End------

Cabin and thruster manufacturers focus on optimization

Traditional manual lamination focuses on automation and sealing

Closed form future applications.

Boeings large wing pod has a hinged panel that can be shot

Open the jet engine for inspection. Pay attention to the front air intake hood and lip edge.

The pod panels are being made using Invar concave dies. Laser projection helps with the lamination.

A Goodrich breakdown diagram shows the various components that make up the cabin.

A close-up of the Goodrich acoustic panel shows the core stack

Punches that contribute to the attenuation of noise energy.

The streamlined shape of the aircraft pod, which surrounds the jet engine, conceals its potential complexity. While providing an aerodynamic shell to minimize drag, the pod also features de-icing capabilities, noise reduction, and a reverse engine thrust braking mechanism. Composite material engine pods were first conceived and manufactured in the mid-1970s, with the aim of reducing weight, improving engine fuel efficiency, and, most importantly, reducing engine noise to comply with increasingly stringent airport noise regulations. Today, most commercial aircraft, especially those with long-range capabilities, are equipped with composite material engine pods.

The pod and thrust reverser market is a significant business: Nigel Barker, the R&D director of Goodrich (formerly Rohr Corporation, located in Chula Vista, California), stated that the total market size, including commercial transport, business jets, and general aviation aircraft, is approximately $2.8 billion annually. According to Janes Information Group, Boeing and Airbus aircraft currently require about 1,000 engine pods each year. Major manufacturers include Goodrich Aviation Structures; Boeing (Wichita, Kansas); NORDAM Group (Tulsa, Oklahoma); GKNAS (formerly GKN Westland Aerospace, St. Louis, Missouri, and Whitehaven, UK); Vought Aerospace (Dallas, Texas); Middle River Aircraft Systems (MRAS, Baltimore, Maryland, USA), a division of General Electric; and Hurel Hispano, a new division of Snecma Group (including the former commercial jet engine nacelle manufacturer Hurel Dubois). Hurel Hispano manufactures pod structures for Airbus (Meudon-la-Forêt Cedex, France). Many small companies produce spare parts and replacement components under the supervision of the Federal Aviation Administration. (FAA) Model Certificate.

Here, CW delves into the construction of these complex structures and talks to three top pod manufacturers about manufacturing strategies beyond traditional laminates.

Overview of the capsule

In brief, the nacelle is similar to the hood of a car. It is cylindrical and serves as the aerodynamically smooth outer cover of the jet engine. The nacelle surrounds and encases the front part of the engine —— or the wider intake, while being narrower at the rear. As background, the jet engine draws air through the intake. Part of this air is compressed and burned in the combustion chamber, then expelled as a high-speed exhaust jet. A large volume of air bypasses the combustion process and is pushed backward by high-speed internal fans (such as fans) through bypass ducts. This bypassed air mixes with the hot core exhaust, achieving total thrust with less fuel consumption and reduced noise.

The first third of the pod, known as the intake, is a smooth opening that guides air to the engines fan and compressor blades. While the intake is primarily made of composite materials, the leading edge, known as the lip skin, is typically metal to prevent damage from debris kicked up during ground operations or landing. The intake usually includes an integrated de-icing system, heated by the engines hot air to prevent icing. The middle third is the fan shroud, a cylindrical sleeve that covers the fan, compressor, and the combustion chamber of the engine. This fairing typically has two, three, or more hinged panels that can be raised for engine inspection and maintenance. Small inspection doors are cut into the fairing to facilitate visual checks on critical engine components.

The third and most complex part of the pod, with the largest load, is the thrust reverser. As its name implies, the thrust reverser redirects the flow of exhaust from the jet engine and/or bypass air from back to front in order to decelerate during landing or refusal to take off.

There are generally two types of thrust reversers: 1) the can or target reverser, which opens like a clamshell to block the engine core exhaust and bypass air, redirecting it forward; or 2) the cascade type reverser, where a large panel (transchols) slides back to expose an open grid or cascade, through which only bypass air is redirected. The Barker is a typical example of a thrust reverser found on business and commercial aircraft with fuselage-mounted engines, such as the McDonnell Douglas MD-80, while the cascade type is commonly found in wing-mounted engine pods, such as those on the Boeing 737,747,757,767, and 777.

Kevin Jackson, the technical sales manager of NORDAM Groups NORDAM Pod/Thrust Reverser System Division, stated that there are several reasons for choosing composite materials for the pod, with weight being the most significant factor. Jackson explained, 'Most business jets have a rear-mounted engine, positioned as far from the center of gravity as possible. By making the engine pod and thrust reverser lighter, it not only reduces the weight at the engine position but also decreases the overall weight of the aircraft, as you dont need to add as much weight to the nose to balance the aircraft.'

The pod, especially the thrust reverser, must be robust enough to withstand the air loads during flight and braking. However, Jackson noted, 'If we make it rigid enough to resist deflection, it is usually strong enough to handle these loads.' Buck from Goodrich emphasized that eccentric loads are even more critical. He explained, 'If an engine loses a fan blade, the unbalanced fan can generate a force at the intake that exceeds anything seen in flight.'  'You also need to consider impact loads, such as when a pipe in the engine ruptures, which can cause impact loads, as well as acoustic vibration fatigue and the air load that prevents takeoff. The pod design involves balancing various performance requirements.'

Temperature resistance is another key design factor, especially for the thrust reverser. Mike Borgman of Boeings Stress Engineering Group at the Wichita Strut, Cabin, and Composite Materials Responsibility Center noted that cooler bypass air often isolates the pod and thrust reverser panels from the hot core exhaust flow, making high-temperature (177°C/350°F) curing epoxy resin a suitable choice, provided that the parts near the engine are insulated. 'However, even with our insulation, we are approaching the usage threshold of epoxy resin. We aim to eliminate the weight and cost associated with insulation. A composite resin system capable of operating at temperatures higher than BMI (bismaleimide) is needed. Polyimides and high-temperature oligomers have potential, but their material costs and processing difficulties currently limit their use. We are always looking for materials that can operate at even higher temperatures.' John Welch, a deputy technical researcher at Wichita University, added, 'Research institutions like NASA are continuing to advance material systems.'

The pressure to reduce aircraft noise is increasing, leading manufacturers to incorporate sound attenuation features into the cabin and thrust reverser structures. While some panels and smaller maintenance doors are solid laminates, most components are structural core sandwich panels designed to absorb sound energy while maintaining sufficient strength to transfer loads between the engine and the aircraft. Thousands of holes, typically 1 millimeter (0.04 inches) in diameter, are drilled into the inner skin of the panels that come into contact with the engine airflow. These perforations help attenuate the noise of the jet engine by damping the energy response, guiding sound into the honeycomb core rather than a rigid surface that simply deflects it. Most suppliers add perforated inner membranes or porous layers to the honeycomb core, effectively doubling the number of cells to achieve greater noise suppression and a wider attenuation frequency range. Various proprietary methods are used to sterilize the core, such as immersing it in resin or sandwiching the material between two or more honeycomb layers.

The pod is a complex assembly of multiple curved panels of varying thicknesses, which are assembled to enclose the engine. Manufacturers typically hand lay these panels in both the female and male molds. For example, the Boeing 777s cascade thrust reverser consists of a smooth outer sleeve (ultimately painted), which can be a sandwich panel or a reinforced solid laminate; an internal acoustic liner sandwich panel; and smaller inner wall components that match the engine combustion chamber. The gap between the inner wall and the outer/acoustic panels forms a bypass air passage. All parts are equipped with a combination of composite and metal joints that can be connected to the engine. Additionally, these panels support hydraulic hoses, electrical, and air lines related to engine functions. A metal mesh is typically included in the outer laminate for lightning protection. The engine is bolted to the suspension structure or pillar, which is part of the aircrafts fuselage, with the cabin panel shaped to fit the suspension.

    Design and manufacturing efficiency simplifies manual lamination

Boeing is both a buyer and a manufacturer of pods. While many parts of its commercial aircraft, including some cabin components, are subcontracted to Tier 1 suppliers, Boeings Wichita division is responsible for manufacturing and assembling pod components for the 747,757, and 767 aircraft, as well as thrust reversers for the NG737 (Next Generation) and 777 models. The company adheres to established pod manufacturing methods, using standard qualified materials, while introducing innovative advancements.

Doug Scott, the director of 737 and 777 thrust reversers at Wichita Group, stated that the company manufactures components for thrust reversers suitable for all three major jet engine suppliers: —— General Electric, Pratt & Whitney, and Rolls-Royce. 'We have a long history in metal, but we are seeing a decline in composite materials, which compete on a cost basis with metals. We implement lean manufacturing and work closely with suppliers to reduce costs and shorten lead times.'

Welch stated that the design of the composite cabin components is aimed at rapid manufacturing, achieving the minimum number of parts through integration while minimizing part complexity. The current transfer hub assembly integrates a significant number of parts that were previously designed as separate components. Welch noted, 'Our NG737 and 777 transfer hub design has reduced the number of parts by 66%, the weight by 25%, and assembly time by 22%.' The hand-stacking process has been streamlined as much as possible. A dedicated material cutting and matching area is equipped with several automatic cutting tables, which can prepare part kits as needed. These kits are then packaged and delivered to technicians, who lay the materials into concave and convex metal Invar molds. Scott mentioned that the materials come from 'a typical supplier,' and his materials are qualified for most Boeing aircraft projects. The laser projection system from Laser Projection Technologies, Inc. (London, New Hampshire, USA), enables effective layering.

Boeing Wichita produces its own tools for the production of pod components internally. Bogman stated, 'We are currently trending towards using Invar tools.'  'Compared to carbon fiber composite tools, they offer a lifecycle advantage and provide a more uniform curing temperature distribution across the parts surface area. We have found that this is crucial for maintaining consistent part quality when curing large components in large hot press tanks.'

Scott noted that one of his companys manufacturing innovations is to use a dedicated tool for each part throughout the entire manufacturing process —— from manufacturing to curing and final processing, the parts remain in a single tool until completion. Scott explained, 'We can control the changes in the parts through this process.'  'By removing the parts from the layered tool and placing them in different milling fixtures, we can induce changes.'

Boeings pod panels incorporate a noise suppression patent innovation developed by the Wichita Group over a long period. The team uses a proprietary method to create acoustic perforations on the inner layer of the panels. According to Welch, 'We mold holes in the skin facing the sandwich during the curing process, making them stronger than other methods like drilling, thus offering a weight advantage.' Various core materials, including aluminum, fiberglass, and asphalt-based carbon fiber, are used. Boeings acoustic diaphragm is inserted using a proprietary process that involves laser drilling to create holes, effectively doubling the number of chambers.

Bogman points out that the company has expertise in producing very thick sandwich structures for thrust reversers, which provide nesting space for the 'block door' when not deployed. (The windscreen is an inner plate that blocks bypass air and directs it through the blade grid.)

Bogman explained, 'We create a folded pocket by stacking thicker cores (over 3 inches) on thinner cores (about 1 inch) separated by an intermediate lamination board.'  'Then, we laminate the thick cores onto the lamination board to form the pocket.' To address the original honeycomb edge issues, Bogman mentioned that edge sealing material is added during the manufacturing process, eliminating the need for edge trimming after the final panel processing. He noted that a 76 mm (3 inches) thick honeycomb can form a contour with a radius curve up to 1.1 meters (44 inches).

The maintenance of the pod is a significant concern, especially for aircraft with engines mounted under the wings, which are prone to damage. The circular fan shroud and thrust reverser panels are manufactured in segments (half, one-third, or even one-quarter of the total circumference), allowing for easy removal of damaged sections. However, Bogman noted that this approach comes with more seams, potentially causing aerodynamic disruptions. To minimize air resistance, the substructures supporting the pod and the structural joints are designed with minimal tolerances. Scott mentioned that the company is collaborating with the National Institute of Aeronautics Research (NIAR) at Wichita State University to continuously refine maintenance techniques. In addition to collaborating with NIAR, FAA, and other entities on maintenance research, Boeing has developed maintenance toolkits for fleet customers, which, with the support of Boeing personnel, can complete on-site repairs within days. The Boeing Wichita plant, certified by the Federal Aviation Administration (FAA), averages 200 pod components repaired annually.

Scott stated, 'The diameter of the 777 pod is roughly the same as that of the 737 fuselage.'  'We have found manual lamination to be an effective solution, but as we move towards the 787, we are exploring automated methods.' The company is also researching new resins and additive materials to enhance high-temperature performance, such as adding phosphoramidite to polyimide in extreme high-temperature conditions.

The legacy of capsule design

Goodrich entered the pod and thrust reverser market by acquiring Rohr, a company that produced the first commercial composite material pods. Goodrich provides complete pods for Airbus A300, A310, A320, and A340, as well as Boeing 717. The company also manufactures cabin parts for Boeing 747 and 767, and produces air intakes and fan shrouds for the 737NG. Recently, Goodrich was selected to provide engine pods for Japans new military cargo aircraft, the C-X. Buck stated, 'For long-range aircraft, the design is being pushed towards composite materials to gain weight and other advantages, such as resistance to de-icing fluid corrosion.'

Like other suppliers, Goodrich uses standard engineering design tools, including Dassault Systems (Woodlands, Calif.) CATIA, NASTRAN and PATRAN for structural analysis, as well as in-house developed laminate design codes.

Buck stated that the companys acoustic panel, branded as DynaRohr, is manufactured using a unique manufacturing process. Goodrich employed a dissolution technique known as NPT (New Perf Technology) to create perforations in the carbon fiber/epoxy skin of the pod and thrust reverser interlayer plates. This method involves placing perforated plates on selected honeycomb materials, such as aluminum, glass fiber, aramid, or titanium. The holes are created using a proprietary blasting medium propelled by compressed air. To create the diaphragm within the core, Buck mentioned that a very fine area-weighted woven mesh is bonded into the core blanket, forming a double cavity within each core unit. He emphasized, 'Our DynaRohr acoustic panel has been proven through testing and modeling to suppress a wider range of sound frequencies compared to other designs.'

Bucks team has been exploring new materials and manufacturing methods. While most manufacturing processes involve manual layering in steel tools, the companies under investigation have explored fiber winding to enhance efficiency. Today, Goodrich is experimenting with liquid forming techniques, such as resin film infusion (RFI) and resin transfer molding (RTM), to reduce costs. These techniques are based on successful prototype parts built for NASAs reusable space launch vehicles. Buck mentioned that a proprietary method for sealing the honeycomb core to prevent resin from entering has been refined, making the core suitable for RTM processes. 'Introducing a new manufacturing method into existing projects is challenging. We are currently producing small maintenance doors and other small parts to gain recognition.'

In terms of materials, the company has explored the use of high-temperature polyimide resin in the inner plates of thrust reversers and the engine core shroud. These components include honeycomb sandwich acoustic structures, hollow cap-shaped reinforcements, and solid laminates. The temperature in areas near the engine core and the exhaust port of the jet engine can reach 315°C/600°F. Traditionally, these parts are made from aluminum plates or carbon epoxy resin and protected with thermal blankets. Buck noted that when flight tests exceeded 5000 hours, carbon/polyimide components developed severe micro-cracks.  However, we are continuing to search for composite materials that can withstand such operating temperatures.

Buck stated that Goodrich is a member of the Commercial Aircraft Composite Repair Council (CACRC), and all its products come with a maintenance program. He explained, 'We have a comprehensive product support network, including airline representatives and structural repair manuals, to facilitate the necessary maintenance. Of course, we can perform more customized repairs at our facilities in the United States, Europe, and Asia.' Buck reported that CACRCs airline operator members are advocating for the use of a single maintenance material and simplified procedures, and they are making progress toward this goal.

   Business jet market

On the other hand, NORDAM is the leading manufacturer of engine nacelles and thrust reversers for commercial and small jet aircraft, as well as a major maintenance facility. Its clients include Cessna, Dassault, Gulfstream, and Bombardier. The company produces a variety of nacelle components, including all-metal, metal/composite, and all-composite versions.

NORDAM uses open Invar steel tools for its parts, utilizing 177°C/350°F cured carbon/epoxy resin prepregs supplied by Cytec (acquired by Solvay) and Hexcel (in Dublin, California). Invar steel tools are preferred due to their higher productivity and the large number of parts produced annually. Jackson reports that the company uses automatic cutting and matching workstations from Gerber Technology (in Torrington, Connecticut) to prepare the placement material kits. VISTAGY (in Waltham, Massachusetts) s FiberSIM laminate design software is integrated with the companys CATIA design program and the laser projection system from Virtek Laser Systems (in Waterloo, Ontario, Canada), facilitating stacking within the mold.

All composite cabin and thrust reverser components are cured in the companys two large production hot press tanks. After curing, acoustic panels are drilled into the inner skin of the acoustic panel using custom fixtures to create holes aligned with the honeycomb core, which helps to suppress noise. Jackson noted that the company currently does not add a diaphragm to the core.

NORDAM is set to launch a new thrust reverser product made from carbon fiber/BMI prepreg and glass fiber honeycomb core. 'Our epoxy resin can withstand temperatures of approximately 138°C/280°F in both hot and wet conditions,' Jackson explained. 'With BMI, we can achieve even higher performance.' Although the BMI prepreg is significantly more expensive, it saves 400 pounds per aircraft compared to the metal components it replaces, which translates into overall cost savings for the aircraft in the long run.

NORDAM stands out in the industry due to its active engine and thrust reverser testing facility, which can measure engine thrust levels up to 24,000 pounds and test installed pods and thrust reverser components. Jackson noted, 'Since we are based in the United States, we have not imposed noise restrictions on our facilities to date.' The test tower can measure the pressure, temperature, strain, and vibration of pod components, ensuring that they meet the static noise levels required by the Federal Aviation Administration (FAA).

The company has also been certified by the FAA to perform repairs and maintenance at its Tulsa headquarters as well as in the UK, Singapore and South Wales. NORDAM is also in contact with NIARs repair and material certification program and is currently using NIARs test laboratory to identify composites.

By optimizing manual lamination, pod manufacturers are producing high-performance parts designed for a variety of performance requirements, but automation and advanced high-temperature materials may be the option. ------End------

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Original text 1.《  Designing and manufacturing turbine test nacelles 》 2024.2.16

         2. 《 Nacelle manufacturers optimize hand layup and consider closed molding methods》   2023.3.9

                                         Yang Chaofan May 11,2025