See inside the Brazilian C-390 Millennium that Boeing once wanted to buy but now doesn't have an answer to

Packed with Embraer executives and media, Embraer's C-390 plane flew for about an hour around the English countryside.

The jet was one of many military aircraft displayed at the airshow, sitting alongside larger players like the Boeing P-8 Poseidon and the Airbus A400M.

Both Boeing and Airbus have strong military portfolios but lack a medium-sized airlifter, and Embraer hopes its tactical C-390 can snag business from the world's biggest competitors.

Embraer largely built the C-390 as a replacement option for the world's C-130 Hercules fleet, and Embraer is actively eyeing the US defense market.

Embraer already builds its light attack turboprop, the A-29 Super Tucano, in Jacksonville, Florida. The company showcased the A-29 and its C-390 at its nearby Embraer Executive Jets' headquarters in Melbourne, Florida, in March.

Embraer Defense & Security CEO Bosco da Costa Jr. said in a press release that the A-29 was built "just hours away in Jacksonville, Florida," suggesting the C-390 could also be manufactured in the US — a common requirement for foreign aircraft operated by the US military.

The C-390 outperforms the latest C-130J Hercules plane in speed and payload. Equipped with two IAE V2500-E5 turbofan engines, it measures just over 115 feet long, 38 feet tall, and has a wing span of 115 feet. The C-130 has a longer wingspan and slightly shorter length than the C-390 but is the same height.

Its cargo hold length is about 60 feet, and the maximum payload can handle 26 metric tons (about 57,000 pounds) — with space to accommodate light vehicles, heavy vehicles, and helicopters. That's more than the C-130J's 20 metric tons (about 44,000 pounds).

At full capacity, the C-390 can reach speeds of about 614 miles per hour and has a range of 1,080 nautical miles. By comparison, the turboprop C-130 travels at slower speeds, but newer variants have a longer range than the C-390.

The C-390 has served the Brazilian Air Force since 2019, but rising global tensions have increased the demand for military airlifters.

Embraer recently inked a joint deal with NATO countries Austria and the Netherlands for nine C-390s. The C-390 has also been delivered to Portugal and Hungary — the latter receiving its first on Thursday. The Czech Republic and South Korea have also announced orders for the C-390s in December to replace the C-130s.

Still, only a few dozen orders for the C-390 have been placed worldwide compared to Lockheed's 2,700 C-130 deliveries since the launch of the Hercules program in the 1950s.

"This aircraft is the best choice in the market, offering an unbeatable combination of high performance, advanced technology, and low life cycle costs," Costa said at the airshow in July.

Embraer said its highly flexible C-390 could perform some dozen different missions in one platform — supporting everything from medical evacuations and air cargo drop to weather reconnaissance and aerial refueling.

Converting the jet for all missions takes three hours or less, according to Embraer.

According to Embraer, its C-390 can provide high and low-altitude aerial resupply to remote areas thanks to a calculation system built into the plane that uses an algorithm to determine optimal drop points while giving the pilot an option to manually or automatically release cargo.

Further, up to 64 fully equipped paratroopers can deploy from the back of the C-390 for aerial assault operations. The C-130J can accommodate up to 92 paratroopers.

Pilots and a loadmaster operate the C-390, which can carry up to 80 soldiers in seats lined against both walls of the jet. It's also available for humanitarian aid, disaster relief, and stability operations.

"In a world where climate changes, conflicts, and disasters pose an increasing threat, being able to deliver fast and effective assistance determines success in saving lives, providing shelter, and restoring services," Embraer said on its website.

For example, in March, the C-390 transported 18 tons of donations, like non-perishable food, water, and cleaning supplies, to flood-affected families in Rio Grande do Sul, in the south of Brazil.

The C-390 can accommodate up to 74 stretchers, eight other people, such as medical attendants, and any necessary life-supporting equipment.

Four observation windows, special night vision, and a removable fuel tank that extends the plane's range make it ideal for day or night search and rescue operations.

The C-130 can accommodate about the same number of stretchers, also known as litters.

Embraer's transport plane becomes the KC-390 ranker when in aerial refueling mode. It can refuel planes, helicopters, and other C-390s.

In September 2022, the planemaker signed a deal with American defense company L3 Harris to create a boom-equipped "Agile Tanker" KC-390 to refuel the US Air Force fleet, especially in "contested logistics environments."

The Hercules can also refuel most jets and helicopters midair in its specific KC-130J tanker configuration.

Embraer's C-390 is equipped with a "roll-on/roll-off aerial firefighting system" capable of delivering up to 3,000 gallons of retardant. The manufacturer said its C-390 firefighting capabilities meet US standards for performance and coverage.

In June, Air Data News reported that the aircraft carried out its first firefighting mission by dropping 12,600 gallons of water onto fires in the Pantanal wetlands in Brazil.

According to the US Forest Service, the competing Hercules can be configured with portable fire retardant delivery systems for aerial firefighting. The C-130H variant fighting California fires as of August can carry 4,000 gallons of retardant, the state said in a press release.

The C-390's fly-by-wire system reduces the workload for the flight crew and improves their control of the plane, especially at low altitudes where it is refueling, firefighting, or performing search-and-rescue.

Further, the jet boasts an advanced suite of self-protection systems, including ballistic protection, laser and missile approach warning systems, stall protection, tactical radar, and threat detection systems. Embraer says the C-390 was built with "survivability in mind."

Embraer told BI at the airshow that a primary reason to add the full-sized, private bathroom was because of the growing number of women serving in global militaries. The C-130 has a toilet system, but users have only curtains for privacy.

The C-390 also has heated floors, temperature control, and reduced vibration and noise for passenger comfort.

The US Air Force operates the giant C-17 military plane, which has a 164,900-pound payload and four Pratt & Whitney F117-PW-100 jet engines. It can perform various missions, such as transport, airdrops, and humanitarian flights.

Its high speeds are comparable to those of the C-390, and Embraer is seemingly trying to muscle out the turboprop C-130 with a jet-powered airlifter that's smaller than the C-17.