Boeing Company ( BA ) shares slipped Thursday after fresh uncertainty emerged around one of its most closely watched commercial deals, even as the aerospace giant secured another U.S. military contract.

On Wednesday, the U.S. Air Force awarded Boeing ( BA ) a contract exceeding $173 million to supply eight additional MH-139A Grey Wolf helicopters, along with training and sustainment services.

The aircraft, built to guard intercontinental ballistic missile fields, offer higher speed, range, and payload capacity to bolster national security missions, program director Azeem Khan said.

Also Read: It's Boeing Vs Northrop As Pentagon Reportedly Okays Next U.S. Navy Fighter Jet After Delays

Why Is Boeing Stock Falling?

Turkish Airlines Chair Ahmet Bolat warned that the carrier could abandon its provisional agreement to buy 150 Boeing 737 MAX jets if talks with engine supplier CFM International fail to yield favorable terms, reports Reuters.

CFM, a joint venture between GE Aerospace and Safran SA ( SAFRF ) , is currently the sole engine provider for Boeing's ( BA ) narrow-body lineup.

Bolat said the airline would pivot to Airbus SE ( EADSF ) instead if negotiations remain stalled, citing cost disputes as the main hurdle.

The potential shift comes less than two weeks after Turkish President Recep Tayyip Erdoğan met U.S. President Donald Trump, when the tentative Boeing ( BA ) order was first announced, Reuters adds.

The deal forms part of Turkish Airlines' plan to grow its fleet to roughly 800 aircraft by 2033, following a separate order for more than 200 Airbus jets in 2023.

Bolat's remarks shed light on ongoing tensions in the aviation engine market, where rising maintenance delays and spare-parts shortages have fueled clashes between airlines and suppliers.

Turkish Airlines, already grappling with delays linked to Pratt & Whitney engines in its Airbus fleet, has pressed for more competitive pricing as global demand strains capacity.

According to Benzinga Pro, BA stock has gained over 46% in the past year. Investors can gain exposure to the stock via iShares U.S. Aerospace & Defense ETF ( ITA ) .

Price Action: Boeing ( BA ) shares were down 3.34% at $217.79 at the time of publication on Thursday, according to Benzinga Pro data.

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