Air Flow-By Cooling Technology From Mercury Systems Achieves TRL-8

Mercury SystemsMercury Systems has announced that systems using ANSI/VITA 48.7 Air Flow-By™ standard cooling technology have passed flight tests in multiple manned and unmanned airborne platforms, some in their final mission configuration, thereby achieving technology readiness level 8 (TRL-8). Mercury holds a patent on one implementation approach of that standard, and has revised the licensing fees under the patent to be zero cost.

The open standard Air Flow-By cooling technology (ANSI/VITA 48.7/48.1) encloses both sides of an existing module to create a sealed FRU with level-2 maintenance (L2M) convenience while providing the most efficient cooling solution in a standard 1-inch pitch. Compared to conduction cooling, it reduces module weight by more than 20 percent and reduces the temperature of a server processor by approximately 5 degrees C, resulting in an MTBF five times higher. Compared to air flow-through cooling, Air Flow-By technology cools both sides of the board while maintaining the standard 1-inch pitch, and provides a sealed environment for protection from EMI, ESD, and airborne contaminants. And now Air Flow-By technology has a cost advantage too, with zero-cost licensing of the associated patent. Mercury offers engineering services to help customers with their own implementations of Air Flow-By cooling to ensure program success.

Mercury Systems had developed Air Flow-By cooling technology as an improvement to its finely managed air cooling, the original air flow-through (AFT) technology it developed back in 2003. Air Flow-By cooling technology is the most efficient solutions on the market to achieve a sealed environment that tolerates cooling with air that may contain contaminants. Unlike today's AFT technology that merely adds an airflow heat exchanger to the primary side surface of a printed wiring board (PWB), Air Flow-By solutions cool both sides of the PWB by encapsulating the PWB in a heat exchanger shell such that air flows across both sides of the module for maximum cooling efficiency. The heat exchanger shell creates a sealed environment that protects against airborne contaminants, electromagnetic interference (EMI), electrostatic discharge (ESD), and provides an extra layer of physical security. Even with the increased protection and cooling capacity, Air Flow-By solutions maintain the standard 1.0-inch pitch to avoid a 33% reduction in board count found in AFT implementations that may require the module width to grow to 1.5-inch pitch. Now, Air Flow-by technology also has a cost advantage with its zero-cost licensing.

Air Flow-By technology has proven to be more effective at cooling mission electronics than competing technology such as air-flow through. With the achievement of TRL-8, they want to remove any barriers to the adoption of Air Flow-By technology by all industry participants and to do so have reduced the license fees to zero cost.

Air Flow-By cooling also compares extremely favorably to conduction cooling, which is the legacy rugged cooling technology. For example, on power-hungry processor modules, Air Flow-By cooling enables both increased processor frequency and mean time between failures (MTBF) while decreasing overall weight.

Typical improvements seen include:

  • 25% reduction in processor temperature for dual Intel® Xeon® processors
  • 33% increase in processor frequency at that reduced temperature
  • 5 times increase in MTBF
  • 25% reduction in weight of the processor module


Mercury's US patent 9,389,653 B2 for Air Flow-By Cooling Technology and Air Flow-By Circuit Board Modules has always been available to be licensed to all VITA members under standard Fair, Reasonable, and Non-Discriminatory (FRAND) licensing terms as part of the normal VITA standards process. Today's announcement reduces the patent licensing fees to zero cost under Mercury's patent licensing terms that allow licensees to use claims under this patent that may be essential to create an implementation compliant with the ANSI/VITA 48.7 standard, and it extends those terms beyond VITA members to all industry participants. Licensees just need to sign Mercury's patent license agreement to use the claims under this patent. Click here to learn more.