NTS News Center

Latest News in Testing, Inspection and Certification

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

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!

How will MIL-DTL-901E affect your shock qualification?

Photo: Navy.com

For the past 30 years, MIL-S-901D has defined requirements for shock qualification of items installed on U.S. Navy Combatants. For the duration of this period, there have been rumors of a new and improved specification revision. That time has finally come.

MIL-DTL-901E, revision to MIL-S-901D of 1989 has been approved and released as of 20 June 2017. The new “detail specification” or DTL per DOD 4120.24M is an evolutionary document that includes changes from MIL-S-901D, Interim Change #2, the 2012 DSCR-2 initiative clarification letters and cost reduction strategies, and the Total Ownership Cost (TOC) reduction provided by the Deck Simulating Shock Machine (DSSM).

For most Navy shipboard shock practitioners, the most impactful change to the document is the addition of the Medium Weight Deck Simulating Shock Test.  This test is primarily performed on Class II, deck mounted equipment and utilizes the DSSM. The DSSM is typically used in lieu of performing a heavyweight shock test series.

The DSSM shock test machine at NTS Rustburg

In the early 2000s, we recognized that the current model for shock qualification of a vast majority of the proliferating Class II, Deck Mounted, COTS equipment was not sustainable from a costs and schedule perspective.

So, in collaboration with HII-NNS partners, NTS led the pioneering development of a more cost and schedule effective land-based approach to meet this new challenge. These efforts culminated in the fabrication of the DSSM Generation I machine that has been in use at NTS Rustburg, VA since 2004.

The success of the Generation I DSSM led to the development of a scaled-up Generation II machine that is specified in MIL-DTL-901E. All of the certification testing that was necessary prior to inclusion in the new MIL-DTL was conducted at NTS. We have been routinely conducting shock qualification testing on the DSSM as an Alternate Shock Test Vehicle since 2015.

The DSSM development is yet another example of NTS’ focus on customer driven innovation. If you have questions concerning the new MIL-DTL-901E detail specification and how it may affect your program or have a need for Medium Weight Deck Simulating Shock Tests contact our experts today!

Environmental Testing Coming to Colorado!

NTS is pleased to announce that our Longmont, Colorado facility is now offering environmental testing starting in September, 2016. In addition to our current world-class EMI capabilities we can now provide:

DynamicsNTS Longmont Ling 335 shaker

  • Electro Dynamic Shakers:
    Sine, Random, Classical Shock
  • Shock Testing:
    Aircraft, Transportation, Bump
  • Constant Acceleration, Crash Safety

Environmental/ClimaticChamber 59 w car

  • Thermal Cycling
  • Temperature/Humidity
  • Temperature Shock
  • Temperature/Altitude

Whether you need to qualify for MIL-STD 810, MIL-STD 167, MIL-STD 1540 or RTCA DO-160, we can answer any questions you might have. When you are ready, our team can provide a competitively priced testing proposal and scheduling to fit your needs.

Click here to learn more about the NTS Longmont expanded capabilities.

MIL-STD-461G Released

MIL-STD-461 Testing at NTS

The G revision of the MIL-STD-461 standard was released in December 2015 and is available here. NTS’s Jeffrey Viel’s wrote an article for InCompliance Magazine reviewing the proposed changes which was published back in August 2015. These changes have carried into the final released standard and are worth reviewing.

A few highlights of the MIL-STD-461G standard:

  • FFT receivers are now permitted for use
  • Interconnecting cable routing now specified for floor standing equipment
  • Test method CS106 has been removed
  • Test method CS114 system check updates
  • The addition of test method CS117, conducted susceptibility, lightning induced transients, cables and power leads
  • The addition of test method CS118, personnel borne electrostatic discharge
  • Test methods RE102 and RS103 technical updates

Contact NTS today to discuss your next MIL-STD-461 test program.

Extreme Cold Testing

Thermal Shock Chamber

Thermal Shock Chamber at NTS Tempe, AZ

Environmental testing has been a major component of NTS services since our founding in 1961. Military and commercial standards such as MIL-STD-810 and RTCA/DO-160 include sections for thermal shock, icing, freezing rain, and hail impact.

Thermal shock testing  lies at the most severe end of the spectrum of temperature tests performed by NTS. Thermal shock refers to a very high rate of temperature change and is generally conducted on aircraft components, military hardware and electronics designed to withstand harsh environments.

Because almost all products are subject to shipping, this test may be appropriate for any part that will have to withstand an abrupt temperature change in a short period of time, such as a transition from environmentally controlled storage to the varying environments encountered during transport.

Air-to-air thermal shock testing is the most common test performed at our laboratories. It is conducted by moving the test article from one extreme temperature to another on a mechanical conveyor or elevator, depending upon the orientation of the chambers. Fully enclosed thermal shock test chambers keep the equipment stationary while the chamber temperature cycles.

For very large items that cannot be moved by an in-chamber elevator, NTS can provide fixtures and the right setup to meet applicable test specification requirements while assuring the safety of the test item. In one such case, NTS engineers in Boxborough, MA were faced with the challenge of performing icing testing a on a tall telescoping antenna while it was under operation. A custom 23’ x 7’ 7” chamber with temperature controls was built to accommodate this extreme test.

Other examples of specialty thermal shock testing include a liquid-to-liquid system in which a basket is utilized to mechanically transfer a test article from one vat to another for a higher transfer rate of greater thermal energy. NTS also performs cryogenic testing for launch vehicles, satellites, and related hardware. Two large capacity LN2 pits are available for testing that requires either simple atmospheric or highly pressurized sub-freezing temperature shock.

Give us a call today at 800-649-5289 to discuss your extreme environmental testing!

EMI / EMC Requirements Slideshare Available for Download

On September 17th, NTS conducted a one-hour webinar titled “EMI/EMC Requirements for Navy Shipboard and Submarine Applications in accordance with MIL-STD-461F”. Led by NTS Director of Technology, EMI / EMC, Jeff Viel, the webinar covered the EMI/EMC verification requirements for Navy Shipboard equipment. Common design techniques used to ensure electromagnetic compliance to the control requirements of MIL-STD-461F were discussed.

To download a copy of the slides presented, please click here. For technical help with your current programs, please contact us today at 800.270.2516 or submit a quotation request.

Testing to MIL-STD-810, Method 505? Look no further than NTS Tempe.

Solar1Solar radiation can be very damaging to materials and equipment stored and used outdoors. MIL-STD810, Method 505 is designed to evaluate materials as they are exposed to the radiation and heating effects of direct exposure to sunlight. NTS has developed and is now operating state of the art facilities in Tempe, Arizona for this testing.

Examples of these test materials include:

  • Glazing and transparent armor
  • Carbon fiber, Kevlar and other armor
  • Plastics and elastomers
  • Electrical and electronic components
  • Portable communication equipment
  • UAV and control equipment
  • Alternative power equipment
  • Any material used in outdoor applications

Solar7Proprietary radiation sources provide the spectral content and irradiance to the exacting tolerances required by the standard. In addition to the radiation requirements, the standard also requires that temperature and wind speed also be controlled to tight tolerances.

NTS test cells are purpose built to provide the correct environment to replicate the conditions seen in the field as required by the MIL Standard. NTS radiation sources are engineered to provide the correct spectral content, which includes UVA, UVB, visible, and infrared wavelengths.

Procedure 1 testing (Heating Effects)

  • Used to investigate response temperatures when material is exposed in realistically hot climates, and is expected to perform without degradation during and after exposure
  • Used to generate maximum response temperature of the test item, for use in Procedure 2 solar testing
  • It is preferable to use the solar radiation test rather than a temperature-only test because the effects of differential heating caused by solar radiation on material are unknown

Procedure 2 testing (Actinic Effects)

  • Used to investigate the effects on materiel of long exposure to sunshine
  • An accelerated designed to reduce the time to reproduce the cumulative effects of long periods of exposure
  • Chambers designed to provide enough cooling air to prevent the test item from exceeding peak temperatures that would be attained under natural conditions

Solar3NTS operates several test cells dedicated to solar radiation testing with internal volumes of 1000 cubic feet, which allow economical testing of larger test articles. Multiple radiation sources are available to provide the required heat and radiation in a configuration that allows the test subjects to be irradiated from any angle. Uniformity of the radiation across the test article is controlled within specification limits.

Current capabilities include:

  • Procedure 1 system – 4′ x 6′ irradiated area
  • Procedure 2 system – 4′ x 6′ irradiated area with air cooled Mercury-doped Metal Halide lamps
  • Procedure 2 system – 6′ x 6′ irradiated area with air cooled Mercury-doped Metal Halide lamps

Solar2NTS engineers have designed a user interface system based on LABVIEW software that provides full control of all required parameters for testing. This proprietary software monitors spectral content, irradiance, airspeed, test article and chamber temperature and other selectable parameters and displays the data in real-time. All parameters are plotted to graphical for-mat for review and inclusion in the test report. The system auto-mates the setup and calibration, resulting in better accuracy and lower cost to the customer. All instrumentation is calibrated by an accredited laboratory, and is traceable to NIST. Full equipment lists with calibration traceability are provided with the subsequent test report.

Advantages of the NTS Solar Radiation test system include our ability to handle larger test articles and orientation of those test articles as required. We also offer real-time monitoring/recording of irradiance and spectral content as well as automated data processing and reporting.

For more information on how we can help with your solar testing needs please contact the experts at the Tempe lab directly, 480.966.5517 or visit our webpage for a list of additional services and accreditations.