NTS News Center

Latest News in Testing, Inspection and Certification

NTS News Center - Latest News in Testing, Inspection and Certification

Package Testing

Package testing is a way of simulating the conditions a package can be expected to encounter during transit. In today’s increasingly global supply chains, packages and products will often cross wide geographic distances to get to market, moving through multiple stakeholders using different modes of transportation. A product or component’s packaging must be designed to withstand these environments.

NTS offers package testing to ASTM® and ISTA® standards, among others. We can help you protect your investment, reduce product loss and minimize risk during shipping and transport.

Why Invest in Package Testing?

Package testing has several potential benefits for manufacturers, including:

  • Package testing in a controlled lab environment is more reliable than trial and error.
  • Regular testing helps you understand your distribution environment, so you can make changes that reduce your exposure to hazards.
  • Testing methods and protocol can be reviewed and revised at any time, allowing you to respond in an agile manner to changing products, packaging materials and distribution hazards.
  • The information gathered from testing leads to smarter package design, which in turn helps you transport products in a safer manner.

Ultimately, these benefits will save you money and reduce shipping bottlenecks caused by damaged products and packaging failures. Ongoing investment in testing will deliver strong returns over time, making your business more stable and sustainable.

Common Modes of Transportation

An understanding of the conditions your package will encounter during transit is essential to designing a package test program. A package may be transported by:

  • Road
  • Rail
  • Sea
  • Air

As well, it may move through different vehicles and vessels and change hands between organizations several times during transit. A large part of package testing involves anticipating the impact these transitions will have on your product.

Industry Package Testing Standards

The diversity of conditions and stakeholders involved in transporting a product to its destination requires unified testing standards. The following organizations have established package testing guidelines for use by organizations in a range of industries:

  • ISTA
  • ASTM
  • IEC 60068-2-55

Package Testing Methods

NTS’ package testing methods include:

  • Vibration
  • Loose cargo
  • Freefall drop
  • Shock
  • Incline impact
  • Horizontal impact
  • Compression
  • Temperature and humidity

We can perform package vibration testing, loose cargo testing, freefall drop testing, shock testing and temperature and humidity testing to ASTM or ISTA standards. Our engineers can also design a custom testing program according to your specifications. Either way, our team will work with you to assess your requirements and deliver customized service.

ISTA Package Testing

The International Safe Transit Association (ISTA) publishes guidelines for two types of package tests:

  • Performance tests, which assess the ability of a package to survive normal shipment conditions
  • Development tests, which measure the relative effectiveness of two or more package designs against each other

ISTA further groups these tests into seven different series, which vary according to the extent and depth of simulation involved, the weight of the product and several other factors:

  • ISTA 1 Series: Non-Simulation Integrity Performance Tests
  • ISTA 2 Series: Partial Simulation Performance Tests
  • ISTA 3 Series: General Simulation Performance Tests
  • ISTA 4 Series: Enhanced Simulation Performance Tests
  • ISTA 5 Series: Focused Simulation Guides
  • ISTA 6 Series: Member Performance Tests
  • ISTA 7 Series: Development Tests

Learn more about individual test series by contacting an NTS representative today.

HALT Product Design and Reliability Seminar

On November 10, 2017  join engineers and technicians from our NTS Chicago facility as they host an all-day, interactive seminar on HALT (Highly Accelerated Life Test) covering the basics, benefits and how it can help you determine your product’s reliability. Additionally, they will introduce other available tools designed to prevent early life-cycle product failure (e.g. HASS – Highly Accelerated Stress Screening) as well as share with you, answers to some of the most frequently asked questions on product reliability testing.

The seminar will run from 9:00 am to 3:00 pm at our Chicago, IL facility. Click here for more information and to register!

Expanding Capabilities in Rocket City

EMI testing Huntsville ALIt has been a busy time at our Huntsville, Alabama test facility! We’re added a number of new chambers, enabling us to expand our test offerings for our defense and aerospace industry clients.

We have added two EMI chambers to our EMI department, bringing us to a total of six MIL-STD-461 compliance EMI Chambers. Additionally, a third new chamber is on the horizon to replace one of our older, smaller chambers. All of our new chambers have a low sill height, which eases the installation process for larger equipment under test (EUT).

The Huntsville EMI facility now has the necessary amplifiers and antennas to allow MIL-STD-461 radiated susceptibility testing up to 40- GHz at 200 V/m. Additionally, new equipment has been added that enables us to perform the common mode test required by MIL-STD-461F/G CS114 in the frequency range of 4kHz to 1 MHz for items that are intended to be installed on ships or submarines.

To learn more about these and other testing at NTS Huntsville, contact us today!



Fuel Icing and Contamination Test Stand Goes Live in Santa Clarita

NTS understands the significant threat to aerospace fuel system components posed by ice and contamination, and that is why NTS Santa Clarita has just completed significant upgrades in its water in fuel, fuel icing and contaminated fuels testing capabilities.

Our novel, stand-alone, water in fuel/fuel icing test stand is equipped to perform testing in accordance with SAE ARP 1401 and MIL-F-8615D on aerospace fuel system components sub-systems and systems, along with our neighboring test stand designed to run contaminated fuel testing in accordance with MIL-F-8615D and SAE ARP-8615.

Our enhanced capabilities allow us to support aerospace fuel system component and/or system testing (including aerial refueling components and systems) with flow capabilities up to 500 gpm at 200 psig.  NTS’ design allows for the ability to perform both recirculated and single pass testing.

Fuel Icing / Water in Fuel Testing

Simply stated, water buildup within aircraft fuel systems becomes ice during changes in altitude, and changes in fuel demand can knock loose this ice, creating significant hazards to fuel system and engine components.  NTS replicates these conditions by injecting a known amount of water into the fuel, then cools the mixture to the required temperatures and flows through the test article.  The mission profile (e.g. Idle, Takeoff, Cruise, Descent, and Landing) is then performed at three temperatures, each representing a different physical state of ice with its own associated failure mode and samples are taken throughout the system to verify the water content meets specified requirements.

Contaminated Fuel Testing

Whether at a commercial airport or the most remote military airfield, contaminants can find their way into a fuel farm and into a plane’s fuel system.  These contaminants have the potential to cause parts to fail over time, whether through wearing out O-rings and seals, or jamming moving parts.  NTS’ test system is designed to test fuel system components’ resistance to failure due to these contaminants by injecting a defined amount and mixture of contaminants into the fuel stream or reservoir and sending this mixture through the test article.  The mission profile is then performed and leakage testing conducted to determine the performance outcome.

These state of the art capabilities, and our partnered approach to testing, uniquely positions NTS to provide you with the testing solutions you need to go to market with confidence. To learn more about the testing capabilities at NTS Santa Clarita, contact us today!

What the FOD? Foreign Object Debris Testing at NTS

“As defined in AC 150/5210-24, Foreign Object Debris (FOD) Management, FOD is any object, live or not, located in an inappropriate location in the airport environment that has the capacity to injure airport or air carrier personnel and damage aircraft.” via https://www.faa.gov/airports/airport_safety/fod/

FOD can be a tool left behind, a piece of debris from a plane that recently departed, or a flock of geese. The presence of FOD is a significant concern for the safety of air travel. Airports, Airlines and manufacturers all play a part in the avoidance and minimization of FOD.

Testing systems and materials to determine their ability to withstand FOD is a key part of the development of safe airplanes. NTS conducts FOD testing at a number of our laboratories, including Tinton Falls, NJ.

The video below shows a 0.75 inch steel ball traveling at 187 mph hitting a 0.085 thick aluminum plate. The takeoff speed of the Airbus A340 and the Boeing 747 is 180 mph. The result is the 0.26 inch deep dent in the plate. The 747 outer skin, made out of aluminum alloy, is just 5 millimeters (0.2 inches) thick. Installed between it and the internal panels are soundproof and heat-resistant insulation materials. The wall is 19 centimeters (7.5 inches) thick.

Lightning Strikes!

Any electronic component is potentially susceptible to lightning damage. As sophisticated navigation and communication systems come to play a larger role in maintaining safe flight operations, lightning testing is an increasingly important part of quality control for both military contractors and avionics equipment manufacturers. Accurately replicating the effect a lightning strike will have on a device is the only way to measure its durability.

Increasing Vibration Capabilities in Boxborough, MA

The already extensive dynamics testing capabilities at our Boxborough, MA location are about to get even better!

We are eagerly awaiting the arrival of our new Unholtz Dickie T2000 – 3 – PB. This new shaker has a 3 inch stroke and a rating of 25,000 force pounds for sine vibration, 23,000 force pounds for random vibration, and 67,000 force pounds for shock. It has a F2000 Field Power Supply and Heat Exchanger with 2 bays, and series/parallel stators for high SRS shock.

This will be the eighth T2000 for NTS across the US, our other T2000 shakers are in Fullerton and Los Angeles, CA, Chicago and Rockford, IL, Camden, AR and in Plano, TX (above on installation day in 2016).

Contact us today to get your vibration testing scheduled! The schedule will fill up fast! Request a quote here, or contact the Boxborough team today!

Essentials of Random Vibration and Shock Testing Training in Massachusetts

NTS ED T-2000 Vibration Test TableJoin us in Boxborough, MA as we host the Equipment Reliability Institute for their “Essentials of Random Vibration and Shock” testing course.

Learn the essentials of random vibration and shock testing with hands-on demonstrations!

Who is this course for?

This course is a must for technicians, engineers, managers, or anyone in need of practical knowledge about mechanical vibration and mechanical shock test, measurement, analysis, designing for dynamics and/or control.

To learn more about this course, click here!

To learn more about NTS Boxborough and their extensive vibration test capabilities, click here!

Lightning Protection of Wind Turbines

lightning protection for wind turbinesOver the past decade, we’ve all watched the world’s energy markets shift towards cleaner, alternative sources. Technological advancements in renewable industries like wind, solar, and tidal, have enabled us to make these potential solutions a reality. As research and development continue to improve efficiency, and drive down cost, these solutions will become more and more prevalent.

We still face considerable obstacles. Wind turbines, in particular, take on one of the largest hurdles; weather. Their fixed location poses unique challenges for turbine and blade manufacturers, which are expected to increase the longevity and reliability of their products without compromising effectiveness, or substantially raising costs. Lightning strikes can cause significant damage to turbines. This damage is extremely expensive to repair, and can shut a turbine down completely.

Severe storms are generally comprised of one or more cumulonimbus clouds, which can be several kilometers in height. As these clouds develop, warm air rises towards the top of the cloud. As the air rises, it becomes cooler. At the dew point, excess water vapor condenses into water droplets and forms the cloud.

When the air has risen high enough, the temperature can drop to -40 degrees Celsius –  water vapor within the cloud will freeze. As ice crystals and hailstones form, and become heavier, they fall through the cloud. When additional water droplets freeze onto the hailstone, small splinters of ice chip off, many of which are positively charged (electrically). Together, these can deposit a net negative charge. Vertical winds carry these smaller splinters upwards into the cloud, while the hailstone falls until it reaches warmer air.

This process causes pockets of electrical charge to form within the cloud, which creates strong electric fields. These electric fields allow charge from the surface of the earth to be “pulled” upwards. in an effort to become charge neutral (typically through tall objects and structures). As these charges get closer together, the electric field in the air further intensifies until it reaches levels of ~30,000V/cm.

When the field intensity reaches these levels, air begins to break down, allowing charge (in the form of current) to flow through the air. Sharp objects significantly intensify the electric field, forming corona (also called St. Elmo’s Fire). Charge from the lightning cloud begins propagating towards the earth. At some point, charge from objects on the ground begins flowing upwards. When these two flows meet, a conductive channel is formed, and lightning occurs.

During a lightning strike, currents of up to (and even greater than) 200,000A travel between the cloud and the object where the lightning channel formed. Wind turbine blades have a sharp, aerodynamic profile – this not only allows them operate efficiently; it also makes them extremely susceptible to lightning strikes. Without suitable conduction paths to safely carry such high current, this transfer of energy can devastate a wind turbine blade.damaged wind turbine blade

Most wind turbine manufacturers strive to make blades and turbines that are more reliable, and can withstand natural phenomena such as lightning. These designs attempt to provide “preferred” current paths for the lightning current; conductive meshes over the exterior of the blades, lightning receptors (preferred lightning attachment locations), and large down conductors, help carry high currents safely to ground.

All of these precautions require highly-detailed planning that includes proper grounding of conductors, shielding of signal wires, wire routing, providing parallel current paths, etc. Despite the complexity of these designs, the benefits are significant; the effects of lightning are not entirely negated, but damage can be significantly reduced – instead of a total blade replacement, getting the turbine up and running again becomes a maintenance and repair exercise.

lightning damage repair progressionThe repair may be straightforward, but it’s still physically demanding. Most modern wind turbine blades are several dozen meters in length. The turbine tower itself can extend 50-100 meters above the ground. Maintenance workers must climb the tower, or be carried up to the blade via a crane. The repair generally involves removing the exterior coating, prepping the damaged area for repair, repairing the laminate, and reapplying the exterior coating.

The physics of nature make lightning almost unavoidable. Therefore, manufacturers must build an effective lightning protection design into the blade.

Most modern design approaches leverage a combination of numerical simulation and testing. Utilizing numerical simulation, electromagnetic models for wind turbine blades can be developed to analyze distributions between structural carbon, and surface protection layers. These models allow the determination of what is electromagnetically important, such as voltages or currents induced throughout the blade, including CFRP pultrusions, heater elements, surface protection layers, and down conductors. They capture critical design details such as material thicknesses, conductor routing, and receptor locations. Further evaluation exposes conductive materials and associated performance risks, such as arcing between blade elements, excessive current in structures, and induced transients into control systems.

After modeling is complete, one or several candidate protection designs is proposed, intending to conduct lightning current with lowest potential for damage or repair. In order for the model data to be considered high fidelity, it needs to be validated by replicating exactly the measurements taken during laboratory tests, and comparing them to the analytical data to determine correlation. This is typically done with high voltage strikes, high current physical damage testing and induced transient tests.

Lightning will always affect wind turbines. It’s complicated, and requires a well thought out design to reduce the severity of damage. If a good protection design is implemented, lightning damage can be reduced to a standard maintenance/repair operation, rather than a total loss.

Justin McKennon is a Senior Engineer and Manager of Simulation and Modeling at the NTS Pittsfield, MA location that specializes in lightning testing and protection services. Justin has a Bachelor’s and Master’s degree in Electrical Engineering from the University of Massachusetts, Dartmouth. He specializes in simulating and modeling the electromagnetic effects of lightning on wind turbine blades, electrical components, aircraft, and other structures.