Boeing and Leonardo’s joint bid for the US Air Force’s UH-1N Huey helicopter recapitalisation did not take off last week after a system aboard the AW139 failed.

Though an impending thunderstorm had threatened to cancel the 25 February media flight, reporters were waiting on the ground next to the helicopter after one of its modular avionics units malfunctioned. The two MAUs aboard the AW139 communicate with each other but also run independent responsibilities such as monitoring the aircraft’s engines. Before the media flight, one MAU gave the pilot a “miscompare,” says Andrew Gappy, director of US Navy programmes at Leonardo.

“I’m not sure what the miscompare was, it was enough to set off a warning light that we were getting a miscompare,” he says. “Part of what you didn’t get to see was that 90% of the avionics are right under the nose, so they were able to pretty quickly open up the nose, do some troubleshooting and say it’s one of the carts inside the MAU that’s failed.”

The pilot could have flown the helicopter, but Boeing decided against the risk. Boeing and Leonardo could have fixed the aircraft on the spot, if they had the part, Gappy says.

“It’s not even very difficult to replace, it’s just not one that’s very common that you would carry it with you,” he says. “It’s not a failure you see very often.”

Despite its aborted media flight, Boeing maintains it could deliver the militarised MH-139 straight off its AW139 production line in Philadelphia, Pennsylvania. Almost 900 AW139s operate around the world and 250 have been assembled and delivered from Philadelphia. Boeing also emphasised its “made in America” tagline, although the company is pairing with an Italian partner.

Boeing will serve as the prime contractor providing the parts, military modifications and logistics support for the AW139. Leonardo will support spares, technology hubs and interim contract support on the flight line, says Rick Lemaster, director of sales and marketing for vertical lift at Boeing.

The team is providing a roomier helicopter for the USAF’s Huey mission, with transmissions contained in the top deck to allow a cleaner cabin space and elevated rotor. The lowest tip of the MH-139’s tail rotor is more than 2.13m (7ft) above the ground, providing safer movement around the aircraft for operators, Gappy says.

While the air force has delayed its final request for proposal for the Huey replacement, Boeing and Leonardo predict their basic MH-139 will meet all of the service’s requirements. The Huey accomplishes a distinguished visitor airlift mission and protects the nuclear intercontinental ballistic missile bases in Wyoming, Montana and North Dakota. Although the VIP mission dominates much of the Huey fleet, Boeing sees the ICBM missile field mission as the RFP’s prime motivator.