Advent Aircraft Systems announced back in February of this year the FAA approval of its GPS/digital anti-skid braking system (known as Advent eABS™) for installation on Beechcraft King Air B300 series aircraft. Curious to know more about the system, we reached out to Advent who gave us an in-depth breakdown.
First and foremost, Advent let us know that eABS’s greatest value comes from the added safety and operational utility it brings to the aircraft through improved braking efficiency. This allows for improved runway performance, resulting in decreased landing distances and takeoff field lengths and offers a reliable, safe alternative to use of reverse thrust (Note: Part 135 and 91K operators cannot use the advantages of reverse thrust when calculating landing or takeoff field length distances).
In fact, with the Advent eABS installed, operators can “stand on the brakes” at touchdown without skidding, flat spotting or blowing a tire. Having eABS brings the true value of the King Air braking system into play for the pilot. This reduces the prop erosion and FOD damage to engines that can occur when regularly using reverse thrust or landing at contaminated runways and allows the quieter, smoother use of ground fine during landing, while focusing on directional control or making that short turn off. For pilots transitioning to the King Air from jets, these are especially attractive features.
Availability of anti-skid also reduces tire wear and keeps brakes in good condition through regular use, which reduces maintenance costs. This can prevent a planned out day from being derailed by a blown tire.
There are many safety systems on an airplane that are not needed – until they are needed. The eABS prevents the danger of wheel lock-up. This can occur when a pilot applies the brakes while touching down on the runway and the friction of the runway surface is less than that generated in the brake. All braking action and directional control is lost for that wheel. While most equate this to landing on a wet surface, this can even happen on a dry runway which is exemplified in NTSB Identification: LAX01LA169:
“The pilot made a normal landing under calm wind conditions. During rollout he applied the brakes, and the right main landing gear brake locked up. The right tire skidded for about 600 feet, whereupon the pilot lost directional control. The airplane veered off the runway, traversed a field, and collided with a fence pole”.
Advent noted to us that quantifying and projecting future events is difficult but one major accident where an airplane is damaged or destroyed, (with the possibility of loss of life), should justify the installation of eABS for many operators. Improving safety is always the best approach. Cars built these days have ABS as standard equipment. Advent asks “Why wouldn’t you have eABS on your multi-million dollar King Air?” Even though many King Air pilots may not routinely use brakes on the landing roll, there may well be the one landing when ABS will save the day.
The lightweight (24 pounds installed) system is fully compatible with the current King Air’s braking system. It’s the only patented system designed and certified for light turbine aircraft with un-boosted brakes. This would apply to most turboprop aircraft with a Maximum Takeoff Gross Weight of less than 20,000 lbs. and light jets. It’s certified for use with King Air avionics suites including Collins Pro Line (II, 21 or Fusion) GPS-4000S; Garmin 400W/500W series; Garmin G1000 with GIA-63W or any WAAS enabled GPS.
Advent’s also gave us their Pilot in Command (PIC) and Operational values of the eABS system:
⦁ Better directional control and reduced stopping distance based on flight tests gathered during company performance testing in collaboration with Beechcraft demonstrated a reduction in B300 landing distances and takeoff field lengths of approximately 5% and 10% respectively with the Advent eABS installed and without the use of reverse thrust in dry runway conditions. These reductions were most evident for high, hot and/or heavy conditions, allowing valuable new payload/range tradeoffs for the operator. Advent is seeking certification of a flight manual supplement to formalize these improvements, again in collaboration with Beechcraft.
⦁ Eliminates flat-spotted and blown tires during aggressive stopping on dry or contaminated runways. Extends tire life by eliminating hard skids.
⦁ During anti-skid operation, the brake pedal “pushes” back, annunciating its operation. This haptic feature will aid the pilot in knowing the braking limits of the airplane.
⦁ Provides a stopping alternative to reverse thrust the PIC can use with confidence when needed or desired. A contaminated runway, a single engine landing, a rejected takeoff due to an engine problem may be examples.
⦁ eABS will not operate in anti-skid mode when aircraft speed is below 15 knots. This facilitates maneuvering of the airplane during taxi.
⦁ Wheel speed must spin up to at least 85% of aircraft speed (about 50 to 100 milliseconds after touchdown) before brakes will operate, providing the PIC with touchdown protection
⦁ The non-invasive, easy to install system requires minimal down time, either as a stand-alone installation or during scheduled maintenance. For the King Air this is typically as few as 7-10 days.
⦁ A two year extended warranty covers the installation and parts providing increased customer service. The eABS components are also maintained “on condition” alleviating any scheduled maintenance.
The Advent ABS King Air dual wheel system consists of left and right brake control modules, left and right inboard and outboard wheel-speed transducers, two digital electronic control units and a combination ON/OFF discrete cockpit switch with ABS ARMED and ABS INOP annunciators. The current King Air brake reservoir, master cylinders and brake pedals, parking brake controls, wheels and brakes remain installed when the ABS equipment is added.
It is shipped as a complete kit that includes all required system components, installation hardware, installation drawings and certification approvals required for the Advent eABS to be installed on the King Air. Advent Aircraft Systems is providing on-site installation training and liaison engineering support for initial King Air installations. The installation is estimated to be completed within in 91 man hours not including interior R and R. The eABS is available at all Textron Service Centers and Advent Authorized Dealers (see www.aircraftsystems.aero for more information).
About Advent Aircraft Systems
Advent Aircraft Systems developed the patented eABS for a wide variety of light turbine aircraft applications, offering on time delivery, exceptional quality and operating to FAA approved PMA processes.
Advent Aircraft Systems, Inc. designs, engineers, analyzes, manufactures, tests, certifies and supports proprietary components and systems for aircraft and serves aircraft OEMs, major subcontractors, modification centers and aircraft owners and operators in the corporate, commercial, and government aviation markets worldwide. Customer support is offered through sound financial backing and continued investment in capabilities and improved operating efficiency. Advent Aircraft Systems is focused on cost competitiveness and reliable quality and delivery. The companies’ highest priority is responsiveness to customers, based on a comprehensive understanding of their requirements.
Advent eABS and eABS are trademarks of Advent Aircraft Systems, Inc.