Power Conditioning Keeps EFBs Cool

Lithium batteries power the portable electronic devices that make life more enjoyable and work more efficient. Just ask any pilot with an iPad Electronic Flight Bag (EFB). But these rechargeable power sources have a dark side. When they lose their cool, a  thermal runaway threatens everything around them. 

Given the battery’s size, how bad could the risk of fire, explosion, and toxic fumes be? Consider the following, and remember that regardless the source—external or internal—heat is heat. 

Power Conditioning Keeps EFBs Cool
FAA Fights Lithium Battery Fire
After analyzing the 92 battery incidents of all types that occurred during transport operations between 1991 and 2007, the DOT determined four likely causes. Only one, the second on the list, is a risk for EFB: in-use with improper charging and discharging.

Think of rush-hour commuters heading in opposite directions on the same path at the same time. Outbound power flows from the negative to positive terminal. With a voltage higher than the battery produces, the charge muscle’s its way in, positive to negative. How much power the EFB needs for the selected task complicates this conflict. 

There are two ways to mitigate this risk when bringing iPad EFBs into the cockpit: Go with the battery as the primary power and deal with the FAA limitations on use and power levels. Or connect ASIG’s fixed Power Conditioning Module (PCM) or portable Power Conditioning Unit (PCU) to the airplane’s 28-volt DC bus.

PCMPart of ASIG’s flyTab suite of EFB products, both units employ the same technology. In simple terms, they protect the airplane and EFB by constantly monitoring the in-use charge/discharge power requirements and providing clean, filtered power to an Apple 30-pin connector used with the iPad, iPhone, or iPod.

Beyond intelligent thermal management, the PCM/U weighs less than .5 pounds and employs passive (no fan) cooling. They include GFI circuit protection, over-current and over-voltage protection, and connection load sensing. Soft, backlighted LEDs (to protect night vision)  indicate “power available” and “system status.” 

Designed to military specs, the modules exceed the FAA’s Part 25 design and operating requirements for power supply systems for personal electronic devices. And they satisfy the FAA Order 8900.1 requirements in  Paragraphs 4-1644(E)(3) for secondary EFB power sources and 4-1648(A)(1) for EFB power source airworthiness requirements.

Both are designed and tested to meet RTCA/D0-160 specs for 28 VDC electrical transients operating at full load between –40C and 55C. They also proved themselves as neither victim nor source of EMI or RMI, rapid decompression left them unfazed.

Installing the PCM on N-registered aircraft requires an STC and a separate aircraft-specific installation kit, both of which ASIG can provide. The PCU does not require an STC for use with a Class I EFB. For complete details on the flyTab suite of EFB solutions, contact ASIG and learn how you can reap the iPad EFB rewards and mitigate the risks of its lithium power.

Read more http://asigllc.blogspot.com/2011/09/power-conditioning-keeps-efbs-cool.html


White Paper 1    Request Whitepaper


  • Software Developer's Kit
  • flyTab Mount Solutions
  • Power Conditioning Solutions
  • Data Connectivity Solutions
  • flyTab Patent Licensing Program

The flyTab Software Developers Kit (SDK) accelerates aircraft aware iOS applications development with tools, data and simulations intended to ease product development lifecycles.

Read More

iPad Electronic Flight Bag (EFB) solutions require durable mounting options that withstand the rigors of in-flight use. Mounting solutions also need to account for new form factors for future iPad models.

Read More

Implementing tablet-based Electronic Flight Bags (EFB) in the cockpit requires a power source that protects both the airframe and the electronic flight bag itself.

Read More

In the end every air carrier business case manager knows the key to ROI for any Electronic Flight Bag (EFB) program is rapid deployability, minimized implementation cost, and ease of access and distribution of data! Data provides the standard for any solid business case that benefits an organization.

Read More

ASIG is leading the way in researching and developing many new technologies related to NextGen flight including eEnablement, IoT/ M2M, tablet and app convergence in aviation, and advanced data analytics. Along the way, we’ve built an industry-leading patent portfolio, which is now available for you to leverage. With an easy to manage flyTab Patent License, your firm can access worldwide patent assets that may be critical to the success and acceleration of your business and products.

Read More

Proud member of