Heavy maintenance by the numbers - United Hub

Heavy maintenance by the numbers

By The Hub team, March 09, 2016

Heavy maintenance, the task of keeping United's giant fleet safe, reliable and flight-ready is no easy feat. It takes the combined efforts of thousands of people across the globe, and though you may rarely see these dedicated employees at work, heavy maintenance is full of spectacular stats and facts.

One of over 700 United aircraft being maintained


Collectively, the 12,400 men and women of Technical Operations are responsible for the safe and reliable performance of our entire mainline fleet. These dedicated employees repair everything from interior components and mechanical parts to our ground service equipment. Tech Ops is remarkably diverse in the types of jobs, the backgrounds of the employees, the locations and the solutions.

And with any massive-sized operation facility, success is completely dependent on solid planning and ongoing project management. And that's where the Technical Operations planning group comes in. These professionals are dedicated to juggling the week's workload to keep up with or stay ahead of changes in the operation alongside others who are figuring out which aircraft need to be where for what work as much as five years down the road.


United runs maintenance operations all across the globe, from engine testing facilities and fleet upgrade centers to Emergency Maintenance services and Technical Operations. Tech Ops alone is made up of multiple divisions and departments, including Maintenance Operations, the largest by far. We have quite a number of facilities and many provide highly specialized solutions to maintain our fleet.

For example, the San Francisco Maintenance Center featured in the latest episode of Big Metal Bird covers 125 acres and has 2.9 million square feet of working space. This includes airframe hangars, component shops, and an engine/landing gear overhaul shop. On top of that, we have the only engine-testing cell in North America (outside of the manufacturer) that can accommodate the massive 20,000- pound, 112-inch PW4000 engines used on our Boeing 777 aircraft.

In addition to our San Francisco Maintenance Center, we have large operations for Line Maintenance at all 10 of our hub locations as well as in Cleveland and Orlando. Maintenance, repair and overhaul operations also take place in Houston. In addition to scheduled maintenance, many modifications are handled at our line stations such as the installation of new seats and Split Scimitar winglets.


Our fleet is comprised of over 700 aircraft, and services more than 5,000 flights with an average of 4.6 million miles per day. All together, we fly 16 different kinds of aircraft — from dedicated workhorses like the 737 to international-distance runners like the 747.

We also have one of the most modern and advanced fleets in the world, as frequent upgrades and new aircraft purchases have helped us stay ahead of the curve. Our newly ordered Airbus A350-1000s use new Rolls-Royce Trent XWB engines designed to increase efficiency and reduce noise. The upgraded 737 MAX uses advanced winglet technology to help reduce fuel costs, and incorporates improved ventilation to increase passenger comfort. And of course, we have the new 787 Dreamliner, which is built with 50% composite materials to create a lighter, more efficient aircraft and incorporates a highly advanced anti-turbulence device to provide a smoother ride through moderate turbulence.

It's amazing what can be done when you combine incredible technology and the right people. Managing the heavy maintenance of a fleet this size is a big endeavor, but thanks to our incredible employees, we're confident day in and day out that our planes will take to the skies safe and sound. Take a behind-the-scenes tour of our Heavy Maintenance operation on the latest episode of Big Metal Bird.

United cargo-only flights transport critical goods

By The Hub team

When the pandemic began, United Cargo knew it would be critical to utilize its fleet, network and industry-leading pharmaceutical handling processes to transport a COVID-19 vaccine when the time came.

Connecting vaccines to the world: United responds to mass distribution effort

December 22, 2020

On November 27, United Airlines became the first commercial airline to safely deliver the first batch of Pfizer and BioNTech's COVID-19 vaccine into the U.S. thanks to a coordinated effort between United's cargo, safety, technical operations, flight operations, regulatory and legal teams.

Now as the entire shipping and logistics industry bands together to widely distribute vaccines, United is leveraging all of its flights, including cargo-only and those carrying passengers, to transport millions of vaccines to destinations throughout our network, including Honolulu, Guam and Saipan – the first of any carrier to do so.

United Raises Miles for Dozens of Non-Profits that Rely on Travel

Airline and its customers use crowdsourcing platform - Miles on a Mission - to donate more than 11 million miles for charities like the Thurgood Marshall College Fund, College to Congress and Compass to Care
By United Newsroom, December 01, 2020

CHICAGO, Dec. 1, 2020 /PRNewswire/ -- United is inviting MileagePlus members to give back on Giving Tuesday and throughout the holiday season by donating miles to nearly 40 non-profits through United Airlines' crowdsourcing platform, Miles on a Mission. Non-profits like Thurgood Marshall College Fund, College to Congress and Compass to Care are attempting to raise a total of more than 11 million miles to be used for travel for life-saving health care, continued education, humanitarian aid and more. United will match the first 125,000 miles raised for each of these organizations to help ensure they meet their goals.

United Raises Miles for Dozens of Non-Profits that Rely on Travel

Why we fly

By The Hub team, November 27, 2020

In October 2019, we launched a first-of-its-kind airline miles donation platform, Miles on a Mission. In the inaugural year, MileagePlus members donated over 70 million miles, with United matching over 20 million miles, to 51 organizations. These miles have allowed for these organizations to do important, life-changing, life-saving work in the communities we serve around the globe.

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