From a Simple Idea, a Standard of Safety

Safety in any industrial environment is always of the utmost concern. In aircraft maintenance, it is of special concern and is always taken seriously.

In the fall of 1990 at an aircraft maintenance facility, an open circuit breaker was accidentally closed during maintenance of a fuel system. Several hundred pounds of jet fuel were pumped into the airframe before the breaker could be deactivated, narrowly avoiding a potentially catastrophic accident.

After quick thinking and efficient implementation of safety protocols had prevented injuries or further damage to the aircraft, technicians from several departments were called into action for the critical recovery of the aircraft.

One of those technicians was Keith Blank. While spending many weeks on the cleanup and repairs he thought quite a bit about the safety of maintenance technicians and the protection of valuable aircraft.

Keith realized there were no secure solutions available and technicians used a variety of inadequate tools like rubber bands, cable ties or safety wire to identify and lock out open circuit breakers. In the case of cable ties, push-pull buttons were often damaged when the ties were cut off with wire clippers. Rubber bands could be accidentally compressed, closing the circuit, even if only for a moment and lengths of wire were cumbersome to unravel. In addition, many of these items ended up on the cockpit floor.

Even after leaving the aviation industry to pursue an engineering career, he couldn’t get the problem out of his head. Finally, in a graphics design class, he put his ideas to paper; a simple clip-on device that could be easily installed and easily removed without damage. A permanent, re-useable clip with the added advantage of leaving no expendable by-products in the aircraft.

Keith took his drawings to a small manufacturing firm in Charlotte, North Carolina. After some discussion, slight modifications and production considerations, a design emerged of a simple device consisting of two identical halves held together by a silicon O-ring that would be pinched onto an open circuit breaker button preventing accidental closure and activation.

The company helped in the development of an injection molding tool and was soon producing parts.

Keith took the parts home and sitting before the TV for hours he hand-assembled the two halves with their O-rings, one at a time, producing hundreds of tools which he named Skylox®.

While he knew he had a better solution, with limited funds, his marketing plan consisted of visiting aircraft maintenance facilities and personally demonstrating his idea to the technicians in the hangers.

The genius simplicity of Skylox® as a maintenance safety device was a no-brainer and soon his hard work began to pay off. One by one, maintenance shops began to adopt Skylox® as their standard circuit breaker lockout tool and Keith spent more and more time assembling Skylox® tools in his living room in the evenings. But the downside of such success, was that he soon became overwhelmed by the demand and could barely find the time to do all of the tedious assembly work.

Fate stepped in when Keith met Tom Kassab, an entrepreneur in Greenville, South Carolina who was opening a new business selling HMMWV parts to the military and H1 Hummer parts to civilian customers. But Tom was open minded about what he might be able to sell and after some discussion, Keith went to work for Kascar, LLC as a HMMWV mechanic with Tom agreeing to back the manufacture and marketing of the Skylox® tool.

With connections established through his previous business, Tom had a multi cavity tool made and contracted with an overseas firm to produce and assemble Skylox® by the tens of thousands. Soon Skylox® tools were coming in regularly and major aircraft operators and manufacturers such as FedEx, Delta Airlines and Boeing were buying Skylox® by the thousands.

In 2009 All manufacturing was shifted to a local injection molding company near Greenville where all Skylox® tools are now 100% manufactured and assembled in the USA.

Gradually, customers began to ask if there were more positive lockout devices or tagout options. The first product accessory was a sleeve, named Skyvault® that could be slipped over the Skylox® tool to prevent it from being pinched open without intentionally removing the sleeve.

The development of WARNING, DANGER and MAINTENANCE Skytags® and REMOVE BEFORE FLIGHT Streamers, and an easy to use Skyclip® soon followed. The complete combination of Skylox®, Skyvault® Skyclip® and Skytag® provides a positive lockout-tagout system that guarantees, outside of human intervention, that a breaker cannot be accidentally activated.

In 2009, Skylox® introduced the Skykit® tool accountability kit which allows the technician to assure that all parts of the tool are accounted for, helping to eliminate FOD.

Skylox® now comes in tool accountability kits in black or high visibility red cases in 12, 18, 30, 45, 70 and 225 tool sets. Skylox® themselves are available in 15 colors for color-coding circuits, specific aircraft, individual technicians or whatever may require color differentiation. Large size Skylox® are available in three standard colors to fit 50 amp or other large breakers and positive lockout kits are available with three digit combination padlocks for 100% positive lockout applications.

As of this writing, more than two and a half million Skylox® and Hundreds of thousands of Skyvault®, Skyclip®, Skytag® and Skykit® products have been sold worldwide.

In 2019 Skylox® began a program of donating tool accountability kits to aircraft maintenance schools nationwide to help promote safety standard practices among newly trained technicians. So far over 60 college, universities and trade schools have benefited from this program.

From a simple recognized need, came a simple idea that has blossomed into an ever evolving worldwide solution for aircraft ground maintenance safety.

Spurred by customer requests, the Skylox® team is constantly developing new products and new variations to add to the Skylox® line. Starting with our first twelve piece kit, customer requests have resulted in larger kits of up to 225 Skylox® tools. One customer request expanded the Skylox® color palette from the original orange and yellow to the current fifteen color offering.

The Skylox® team has also worked diligently with regulating agencies in the civilian and military communities to assure that all Skylox® products meet durability and safety requirements, including all requirements of aircraft/aerospace circuit breaker lockout/tagout procedures on electrical circuits, electrical panels in accordance with OSHA as well as AFOSH, NAVOSH and the FAA

Skylox® has been endorsed by NAVAIR and featured at the Joint Services Wiring Action Group (JSWAG) and Joint Services Fiber Optics Group (JFOWG) annual safety conference. Skylox® products are approved for use and as part of the Joint Service General Wiring Maintenance Manual, US Naval Air Systems Command Lockout/Tagout Procedure and has been featured in PS Magazine, volume 743.

Skylox®, LLC (CAGE code 5R8R0) can be reached through its parent company, Kascar, LLC at
or on line at

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