Common Ground: Advances in Powered Support Equipment

Fuel efficiency. Conservation of resources. Ease of maintenance. Reduction of emissions. These terms are regularly cited by the major carriers as areas of concern and continual improvement. Accordingly, they are most often applied to aircraft—specifically airframe power plants. With today’s jet engines nearly 300 times as efficient as earlier models, emphasis is increasingly being shifted toward the ground support arena.

Having spent 25 years as aerospace ground equipment (AGE) mechanic, supervisor and eventual superintendent, I can attest to the many impressive strides toward the goal of efficient, safe operation. With that in mind, I wanted to point out some key areas in which powered ground support equipment (PGSE) has kept pace.

Wide-ranging advances in fuel efficiency, noise abatement, safety and cost control have come to pass, making the operation and maintenance of generator sets, heating, ventilating and cooling (HVAC) units, pushback vehicles and maintenance stands much more effective and less hazardous than ever before. Emissions have been reduced as well, resulting in cleaner air surrounding airports. Often, these advances spring from cooperative efforts between the manufacturers and airline PGSE support staff.

Take the example of Southwest Airlines’ FMC tractor fleet, pulled from a recent edition of SWA Takeoff. Southwest was attempting to convert some of its gas and diesel powered equipment to electric operation in an ongoing effort to reduce pollution. Acting on their own initiative, an enterprising team of Southwest ground support mechanics in Phoenix began experimenting with diesel-to-electric conversions. After some initial success, Southwest approached its primary supplier of pushback tractors, FMC Technologies in Florida, with a proposal: Southwest mechanics and FMC engineers could work together to convert a diesel-powered chassis to electric power at the Phoenix Sky Harbor International Airport facility.

“Next thing I know, Southwest Airlines is in Dallas and Houston putting into service electric-powered pushback tractors built by FMC Technologies that look and operate just like their diesel-powered counter parts,” recalls Larry Laney, director of ground support for Southwest Airlines. “When Southwest started this project we had three objectives:

1) Standardization of equipment: We wanted the units to have common parts for easy maintenance and for the units to feel the same as their diesel counterparts.
2) Control our costs: We felt we should be able to purchase an electric-powered tractor for the same price as a diesel-powered tractor minus the battery pack.
3) Performance: The electric-powered units had to perform as well as our diesel-powered units at the gate. This team of Southwest employees and FMC engineers has met or exceeded our goals by thinking outside of the box,” Laney says.

Southwest Airlines’ voluntary GSE conversion commitment was in jeopardy following the financial catastrophe afflicting the airlines, including Southwest, as a result of the Sept. 11 attacks. Southwest Airlines reports, however, that not only has it continued with its voluntary commitment, but it also has accomplished the conversion a year earlier than the commitment provided. By the end of 2004, Southwest Airlines had acquired the following new electric-powered equipment for operations at Dallas Love Field:

  • 25 electric-powered pushback tractors

  • 48 electric-powered beltloaders

  • 46 electric-powered bag tractors

  • 3 cargo tugs with new clean air technology

  • 3 electric-powered lavatory trucks, containing the equipment to service the aircraft

  • 50 state-of-the-art fast-charging systems to charge all electric-powered equipment

The total cost to Southwest Airlines of converting all GSE at both Dallas Love Field and Houston Hobby Airport is more than $7.5 million.

While PGSE vehicles constitute a large portion of ground-based emissions, aircraft ground operation factors in as well. A prime source of pollution and noise, aircraft auxiliary power units, or APUs, have traditionally been run for extended periods of time.

According to a 2003-2004 British Airways study on airport air quality, “APUs on aircraft are often necessary to provide a source of on board electrical, pneumatic and hydraulic power for the aircraft, and a source of air for the aircraft’s air conditioning systems. Although small by comparison with an aircraft’s main engines, APUs may be required to operate for a significantly longer time on the ground, and therefore cannot be ignored.

“By opting for fixed electrical ground power (FEGP) and pre-conditioned air (PCA) whenever it is available, the emissions from ground power units (GPUs), mobile ground generators and APUs, can be minimized and emissions reduced as a result.”

Along those lines, one area that has taken a quantum leap forward is ground power generation. Rapidly fading into obscurity are the days of fuel-guzzling gas turbine generator sets, with the majority being replaced by more fuel-efficient diesel models or fully electric solid-state power converters. Use of aluminum versus steel in cabinet and frame construction has reduced towed weight significantly, resulting in ease of handling and additional fuel savings from tow vehicles.

The advent of computer technology has reduced diagnostic and maintenance costs as well. Many units on the market today encompass fully-integrated diagnostic software packages, event storing features and error reporting tools. In addition, modern weather-proof enclosures not only provide protection from the elements, they reduce sound-level DB attenuation as well.

With many of the above listed advances incorporated into heating, ventilating and cooling systems (HVAC) as well, environmental control has become a benchmark for industry progress. Utilizing facility hard-mounting or truck/trailer mounted units, modern HVAC systems boast a wide variety of power plants and propulsion methods. Newer and more environmentally friendly refrigerants such as R-134a and R-410a aim at reducing hydrocarbon emissions, and in this area, GSE leads commercial facilities by an enormous margin. Fully automated temperature controls and advanced protection and control features have resulted in “walk away” systems supporting unattended operation.

Of course, none of these advances would be possible without an equally well-equipped support staff. Any system is only as good as the technicians who support it, and those technicians increasingly depend on a diverse array of training solutions.

Disciplines unheard of a decade ago, from on-board computer maintenance to in-office database administration, have become integral components in the ground support professional’s tool kit. Environmental protection and hazardous waste (HAZMAT) containment and disposal have tremendous liability and potential for error, and require training programs that address those issues in a solid and conscientious manner.

Progressive education in both the military and civil aviation sectors has proven crucial to optimizing productivity and maximizing the lifespan of the new technology, and this promises to be a burgeoning area, consuming a growing portion of the ground support budget for the foreseeable future. As in all maintenance endeavors, quality PGSE support requires the dedicated planning and organization of those skilled professionals entrusted to the care of the equipment. Based on the progress I have seen in the last 25 years, that equipment remains in qualified, capable hands.