By Justin Marchand
Contributing writer
(L–R) ENG Director of Operations Ryan Oppel, Chief Pilot Charles Roberts, President Steve Hofmann, Vice President Cat Wren, and Director of Ground Transportation Kalee Blythe on the ramp at HOU (Hobby, Houston TX).
Four-year-old ENG Aviation Group has grown rapidly as a Part 135 operator dedicated to serving life-saving organ transport.
Its fleet currently consists of a Cessna Citation CJ3, a CJ3+, and a 560XL, and plans call for additional aircraft to be added to its certificate.
The majority of its flights are in support of organ recovery missions, and any other availability is supplemented with traditional charter.
The company’s origins trace to ENG President Steve Hofmann’s entrepreneurial background and personal connection to organ donation, creating a mission-driven company rather than a typical charter operator.
He describes the 36-employee company headquartered at HOU (Hobby, Houston TX) as an organ transplant transportation company with a competence in aircraft management and charter. He purchased the certificate of a failing charter company during the Covid-19 pandemic and turned it into ENG’s bundled air and ground transport and logistics services.
“Prior to 2021, transplant centers had a finite radius that they could go out to recover an organ to perform a transplant,” Hofmann explains.
“In 2021, a couple of big policy changes happened so that now transplant centers didn’t have this constraint around geographic regions. This has been great for the transplant centers, and really great for recipients because there’s now a much bigger pool of organs that they can look for to make sure there’s a good match. However, it left a big question – how does a transplant center in Houston TX get organs to Buffalo NY with 2 hours’ notice? The need for reliable, real-time air transportation certainly skyrocketed.”
The answer was ENG Aviation. Company aircraft provide rapid response solutions for organ air transport, ensuring life-saving organs reach their destination safely, securely, and on time.
ENG stands for “Earned. Never Given.” It offers 24/7 access to a medical logistics team with Part 135 aircraft that can coordinate seamlessly with transplant coordinators, transplant centers, organ procurement organizations, and ground teams across the US. Its aircraft average 375–450 hours annually in support of these missions.
“I’ve always had a passion for entrepreneurship,” explains Hofmann. “I think that really just stems from a love of solving complex problems. We started by asking hospitals and transplant centers tough questions about what made them successful and what their pain points were.
ENG Aviation Pres Steve Hofmann built the proprietary fleet management platform Airpeggio, which runs ENG’s operations.
Transplant and donation hits close to home for me. My dad passed away when I was a teenager. He was an organ donor.
That was my first real-life exposure to the importance of donation and transplant. I saw an opportunity to improve people’s lives while solving a lot of problems and challenges.”
ENG VP Cat Wren joined the company in 2024, attracted by the company’s mission to support organ transplant logistics, which she describes as giving people a second chance at life – something she finds deeply motivating.
Her prior 14-year tenure at Business Jet DAL (Love, Dallas TX) gave her broad experience across customer service, marketing, and operations, with a focus on culture and people that she now applies at ENG.
Wren says there were more than 49,000 organ transplants nationally in 2025. “There were nearly 4300 in Texas alone in 2024,” she adds. “We are the essential piece to giving people a second chance at life, and the opportunity to do that every day is absolutely incredible.”
Evolving operations, fleet growth
ENG Aviation has evolved its fleet strategically to better meet the needs of transplant teams. Its focus has shifted from smaller jets to mid-size aircraft for comfort and mission efficiency. The company purchased its first aircraft in 2022. It was a Cessna Citation CJ4 that they chose for its balance of cost, range, and performance. It was especially suited to Texas-based operations, and was selected after considering pilot availability, maintenance network, operating economics, and cabin size.
Vice President Cat Wren spent 14 years in customer service, marketing, and operations roles prior to joining ENG.
However, customer feedback called for additional cabin room. “We’ve learned that the Citation 560 cabin size was a much better fit, particularly for longer-haul trips,” declares Hofmann.
“Not because the CJ4 or CJ3+ can’t perform the mission, but for the surgeons and their assistants, the perfusionists, and the coordinators who are going from case to case. Often, the only time they get to sleep is on the airplane. Having a little bit more room to spread out, rest, and recharge in between cases is important to them.”
Recently, ENG finished conformity on adding a Cessna Citation 560XL to its certificate. The company plans to swap out its remaining CJs for additional 560XL, with 2 of them already on board. “The 560XL offers more passenger space and more room for specialty equipment, but you still retain all of the benefits that Citations are known for,” explains ENG Aviation Director of Operations Ryan Oppel.
“The great short-field performance allows us to get closer to both donors and recipients. The operational costs are great and the ubiquity of those aircraft helps with finding pilots in the marketplace. It is a lot easier to find pilots with prior Citation experience than for something more specialized.”
Oppel is rated in fixed- and rotary-wing aircraft. He joined ENG in April 2025 after 19 years flying air ambulance. Most notably, he spent the preceding 13 years with CareFlite in the Dallas–Fort Worth area, where he served as a pilot, assistant chief, and director of training, working closely with major transplant centers, such as Baylor UT Southwestern and Dallas Methodist. He says a top priority is building a mature flight operations team that fosters a culture of safety and trust with a goal of exceeding Part 135 industry standards.
“I like the 560 for different reasons,” ENG Chief Pilot Charles Roberts explains. “Obviously, the 525 has a much smaller cabin.
Director of Operations Ryan Oppel says the company plans to double the size of the fleet by Q3 2026 and expand into additional states with high transplant demand.
It’s a much more nimble airplane, it flies better on the hands, and it has smoother and lighter controls.
But with the XL, you can’t beat the cabin. It’s really a workhorse. You can load up with six people and still go 1200 to 1500 nm. It offers a great range for our mission profiles.
From Dallas the 560XL can be loaded up with about 4 people and hit any part of the US during normal wind conditions. It’s a really good aircraft.”
Roberts started flying with the American Airlines Cadet Academy in 2018, and then began teaching at the school. While flight instructing on the Cirrus SR22 at an ADS (Addison TX)-based Cirrus Platinum Training Center, he met Hofmann and was his flight instructor for his instrument rating. “He sent me his whole business plan,” Roberts recalls.
“This was in 2022. And I realized he was serious. I was flying jets under the American Airlines umbrella. It just didn’t feel like flying any more, because everyone does all the work for you. You kind of just sit in the seat and show up. So I went to a Cirrus Platinum Training Center. I flew Learjet 75s and 45s for executive charter for a little over a year while helping ENG get the certificate off the ground.”
ENG is standardizing its 560XL aircraft with the Garmin G5000. “The CJs that we currently fly have the G3000 in them. They help with fast turns, allowing us to leave the box loaded before passengers get on board so we can depart much faster,” Roberts adds.
“One of the things with the XL on older models is that they have the old Universal, which doesn’t save anything. When you go to start the engines, you have to turn it off and nothing is saved. And then it takes an additional 10 minutes to get the cockpit ready for taxi. With the G5000 or with the G3000 that we have, it saves everything. So we start engines, taxi, and just go. Everything’s completely ready when passengers board the aircraft. It’s wonderful.”
Chief Pilot Charles Roberts says most transplant flights occur within a 500- to 600-mile radius, and describes the Citation Excel as a workhorse for the mission.
The flight operations department is a small, tightly integrated team focused on consistent, 24/7 customer support through standardized training and coordinated roles.
It consists of core members, such as flight operations analysts, charter sales executives, and flight coordinators on rotation covering 24/7 shifts.
“One of the biggest things with being in a purpose driven 24/7 kind of environment like this is the high level of adaptability and the ability to pivot,” Flight Ops Analyst Bobbi Thiesse says. “At a moment’s notice we get 90 minutes to plan a flight. And it’s not just on our end – it’s on the transplant coordinator’s end and others. Just being able to pivot with other people and do that is always challenging, but it’s a fun challenge.”
ENG started as a software company. The first thing Hofmann did as part of the business plan was to build automation software for a myriad of mundane or undifferentiated activities that aviation companies do.
Hofmann’s goal was “to leverage the human capital and intelligence of all these people in the organization for a much higher level of services, and to put those people’s talents, skills, expertise, and brain power to use in a much more strategic way than doing repetitive things.” The software created, Airpeggio, is a proprietary fleet-management platform that synchronizes ENG’s entire operations and will be made available for other operators as well.
The company stresses the importance of strategic partnerships with several FBOs including Jet Aviation and Galaxy. Currently, all major maintenance is performed by a hand-selected group of MROs, including Elliott, Textron, and Yingling. ENG’s maintenance department performs routine service on the fleet. Part of the company’s growth plan calls for the implementation of expanded in-house capabilities.
Pilot ranks
The flight department is experiencing rapid growth. Oppel says the current pilot count stands at 10, with 2 more captains now being hired and trained. There are plans to add more pilots for the 2 new aircraft. ENG expects to have a team of 18 pilots by early 2026.
Pilot hiring prioritizes candidates with around 2500 total hours, including 800–1000 turbine multi-engine hours. The pilot schedule typically follows an 8-on, 6-off rotation with a 2-hour call-out requirement, allowing pilots to stay home nightly.
This schedule supports strong family dynamics and pilot retention, differentiating from traditional airline commuter lifestyles. “Our operations, with us servicing the organ procurement and the hospitals, mimics a lot more of an EMS model,” Oppel explains.
Director of Ground Transportation Kalee Blythe guides ENG’s ground crew to move organs and surgical crews safely.
“The problem is our flights are a lot longer in duration than your typical EMS patient transport. Those are typically two to four hours, whereas an organ procurement is 10 to 12 hours. And so when you get into conversations of duty time, I can’t schedule my pilots here with a 7:00 am start every day because that 14-hour duty day runs out after the first 4–5 hours of a typical trip.”
Oppel says his goal is to establish a culture and make ENG a place that pilots want to call home for the long term. “I realize a lot of 135 operations are just a stepping stone for pilots who are building hours to eventually get to the airlines,” Oppel adds. At the end of the day, a small 135 is never going to be able to compete with the salary and benefits of legacy operators. What we offer is lifestyle, less time away from home, better work/life balance, more of a purpose to the mission. We’re here for a purpose that serves a greater good.”
“The biggest challenge truly is a constant state of readiness so the aircraft needs to be able to depart within 2 hours from a phone call,” says Roberts.
“The constant readiness that we require from dispatch, maintenance, and our pilots and keeping everyone’s schedule the most up to date so we can actually have a 2-hour call-out for the hospitals that we serve – that’s by far the hardest part. We do a lot of flights to Hammond LA, Houston TX, Kansas City MO, and San Antonio TX, as well as west Texas and other regional flights, but we also get the occasional request to go as far as Seattle, Boston, or Miami. Originating out of Dallas, those 4-hr-plus legs make for long, challenging days, but being centrally based gives us the advantage to reach pretty much every corner of the country in a reasonable time.”
For training, ENG uses CAE Dallas for the 560XL with the Universal. “But our last Universal is getting phased out and replaced with a G5000, which is very cool for our 560XL pilots as it represents an investment in safety and capability,” Roberts adds. “Moving forward, we’ll be able to utilize Flight Safety in Wichita, as they have the only XL sim in the world fitted with the Garmin panel.” ENG’s 525 pilots use FlightSafety Tampa FL.
ENG Aviation also invests heavily in specialized training and high hiring standards to meet the complex, time-critical demands of organ transplant transport. “We spend an enormous time training our pilots and our dispatchers on all matters pertaining to transplant, so that they know the difference between a DCD donor and a DBD donor,” Hofmann explains.
“And so they know the difference between the various perfusion devices. Whether that’s a kidney pump and maybe on a TransMedics device or Paragonix or a cooler or whatever the different equipment that our teams need. We train them on the different cross clamp times for the various organs so that they understand if it’s a lung case, for example, and they’ve got a little more time than say a heart case. A lot of it is just education, communication, training, and a constant feedback loop with the hospitals to make sure that we’re doing really well and we’re able to address the things that we could do better.”
The transport logistics are not just performed by aircraft. Director of Ground Transportation Kalee Blythe oversees a team of emergency vehicle drivers who operate ENG-liveried Chevy Suburbans and are available 24/7 to meet aircraft to assist in moving surgical crews and equipment, or to move crews from hospital to hospital. Just like the aviation portion of the company, she says they are always standing by ready to support the ultimate mission.
“My role is to guide our ground crew to safely move organs, and surgical crews, whether in conjunction with our aviation team, or on our own,” she says. “In this industry, almost every organ will need to be moved via a ground vehicle. We are currently in Dallas and Houston, with 9 drivers, and we have plans to expand very quickly into the markets that most need our services.”
Earned. Never Given.
The company aims to expand beyond its current two bases in Dallas and Houston to multiple regional hubs to better serve organ transplant sectors nationwide. “We are a young company and, with new changes in organ procurement regulations, this allows us to look at a real opportunity to broaden our service offering by adding assets geographically,” Oppel says.
“You’ve got some hospitals that will only fly in a multi-engine turbine aircraft. You’ve got some hospitals, whether they’re in the mid-Atlantic or the Northeast region, who aren’t traversing 1200 miles, meaning that long-haul need isn’t there. So, as we start to grow, our fleet will encompass varying types of aircraft to solve or serve that particular need based on where we’re located.”
ENG plans to expand beyond its current Texas-based footprint and open multiple regional hubs to better serve organ transplant sectors nationwide.
ENG’s growth plan calls for doubling the size of the fleet by Q3 2026 and expanding into additional states with high transplant demand. Expansion involves not just aircraft but also ground vehicles per new location to ensure seamless surgeon transport, reinforcing ENG’s commitment to mission reliability.
On the managed side of the house, ENG is looking to add a number of aircraft. “I love that I get to be part of educating aircraft owners on our business model,” Wren adds.
“We have really introduced a cost offset that owners can count on. Other operators will say, ‘We can charter your aircraft X amount of hours.’ But what is the first thing to go when there’s an economic dip or a countrywide pandemic? It’s luxury goods. People don’t stop needing organs. Our business offers a solid foundation, with revenue coming in to bring down their operating costs, that owners can really count on.”
With a purpose-driven mission within a rapidly expanding industry, look for ENG Aviation to continue blending its passion for aviation, entrepreneurship, and technology to make moves in the organ transplant sector.
Justin Marchand is an aviation journalist who has specialized in writing about technology, corporate flight departments, and pioneering helicopter operators for the past 25 years.
