U.S. aerospace and defense major RTX reported a rise in quarterly profit on Tuesday, as demand for its aircraft parts and repair services benefited from airlines flying older, maintenance-intensive planes to cope with a jet shortage.

RTX shares were up 4% in pre-market trading in New York.  

Supply chain snags and the resulting lack of certain components are hampering production of new commercial jets, forcing airlines to keep their aged fleets in service to meet booming demand for travel.

Taking the shine off RTX's strong quarter, however, the company's 2025 adjusted sales forecast of between $83 billion and $84 billion fell just short of analysts' average estimates of $84.47 billion, according to data compiled by LSEG. 

Troubles at one of RTX's main customers, Boeing, cloud the group's outlook.

"There's a ramp that has taken place in one of our airframers. And so we've calibrated that into our outlook." Chief Financial Officer Neil Mitchill told Reuters in an interview. "Of course, if that turns out to be done at a faster pace, we're prepared to support that level of higher output."

Though U.S. President Donald Trump's incoming administration is likely to increase defense spending, investors are concerned about potential budget cuts under the newly formed Department of Government Efficiency (DOGE) headed by billionaire Elon Musk. 

However, some analysts have downplayed such concerns, arguing Trump's recent comments on acquiring Greenland and taking over the Panama Canal should support the case for increased defense spending. 

RTX's Pratt and Whitney unit, which produces engines for Airbus' A320neo jets and competes with CFM International, reported a sales rise of 18% on a profit of $504 million for the fourth quarter. 

The unit is currently navigating an issue with its Geared Turbofan (GTF) engines and is conducting an inspection drive for potentially flawed components, leading to the grounding of hundreds of planes in recent months. CFO Mitchill told Reuters the company has finalized compensation negotiations with 33 of just over 40 customers in the impacted fleet of jets. Finalizing negotiations means RTX lowers its risk and puts the issue behind them.

Revenue at the company's aerospace and avionics arm Collins Aerospace rose 6% in the reported quarter. 

Raytheon, RTX's defense unit, reported a 36% rise in operating profit due to robust demand for its Patriot defense system used on the battlefields in Ukraine to counter missile threats from Russia. 

By the end of 2025 "we'll have achieved nearly the high end of our $36 to $37 billion commitment that we made to investors following the merger of UTC and Raytheon," Mitchill said.

A prolonged Russia-Ukraine war and ongoing conflicts in the Middle East have led countries to bolster their defense spending, stoking higher demand for arms and weaponry.

Mitchill said that the Ukraine war had resulted in about $10 billion in new orders, out of which 15% has been delivered and the rest will underpin revenues in the coming years.

The Arlington, Virginia-based company reported a 9% rise in quarterly total revenue to $21.62 billion.

It reported a net income of $1.48 billion, or $1.10 per share, compared with $1.43 billion, or $1.05 a share, a year earlier.