Why Howmet Aerospace Inc. (HWM) Stock Fell 7.5% on Aug 31, 2026
The clearest new catalyst: Musk's SpaceX in-house turbine-blade announcement (primary).
Why did HWM stock fall?
Howmet Aerospace fell 7.51% to $244.95 on Monday, August 31, 2026 — its worst single session since April 2025 — after Elon Musk said on Saturday, August 29 that SpaceX would manufacture its own natural-gas turbine blades and vanes in-house, raising fears SpaceX could bypass specialized suppliers like Howmet. A trailing P/E above 57x heading into the session and a modestly risk-off market amplified the decline.
- Musk's SpaceX in-house turbine-blade announcement (primary): On Saturday, August 29, Elon Musk said SpaceX intends to produce its own natural-gas turbine blades and vanes in-house (to address power constraints for AI infrastructure). Howmet is a leading maker of engineered turbine components, so the comment raised concern that SpaceX could bypass specialized external suppliers, threatening a future growth avenue in Howmet's gas-turbine component business. This was the primary driver of Monday's drop.
- Stretched valuation: Heading into the session Howmet traded at a rich trailing P/E above 57x, leaving the stock vulnerable to multiple compression and profit-taking when a negative headline hit.
- Modestly risk-off tape (secondary): The broad market was modestly lower (S&P 500 -0.33%, Nasdaq -0.12%), with rising energy prices and some risk-off sentiment in cyclicals adding pressure. This was a secondary amplifier, not the main cause.
How the story developed
- August 29, 2026 (Saturday)Musk says SpaceX will produce its own natural-gas turbine blades and vanes in-house.
- August 31, 2026HWM falls 7.51% to $244.95 — its worst session since April 2025 — as investors price the risk that SpaceX bypasses suppliers like Howmet.
What it could mean for HWM investors
The constructive case
- The sell-off is based on a potential future sourcing shift, not any deterioration in Howmet's current aerospace and turbine-component business.
- Howmet's core franchise in engineered components for jet engines and airframes is unaffected by the SpaceX comments.
The cautious case & what could invalidate it
- If large customers follow SpaceX toward in-house turbine-component production, a future growth avenue for Howmet could narrow.
- A trailing P/E above 57x leaves little margin for error and invites sharp multiple compression on bad headlines.
- The move rests partly on a single executive's comments, so sentiment can swing quickly in either direction.
Initial detection
BestStocks first flagged HWM intraday on Aug 31, 2026; this analysis was finalized after the close using the confirmed −7.5% session move and additional catalyst research.
Show the initial intraday note
Howmet Aerospace Inc. (HWM) fell 7.51% from a prior close of $264.85 to $244.95 on Monday, August 31, 2026 — its worst single-session drop since April 2025 — after Elon Musk said on Saturday, August 29 that SpaceX would produce its own natural-gas turbine blades and vanes in-house. That raised fears SpaceX could bypass specialized suppliers like Howmet, a leading maker of engineered turbine components, threatening a future growth avenue. A rich valuation (a trailing P/E above 57x heading into the drop) and a modestly risk-off tape amplified the selling.
What to watch next: The key question is how much of Howmet's growth story actually depends on the customers Musk's comments implicate — watch for any company response, order/backlog color on gas-turbine components, and analyst reaction. Because the move layered a specific headline onto a stretched valuation, follow-through hinges on whether the SpaceX threat proves material or is priced as sentiment.
Frequently asked questions
Why did Howmet Aerospace Inc. (HWM) stock fall on Aug 31, 2026?
Howmet Aerospace fell 7.51% to $244.95 on Monday, August 31, 2026 — its worst single session since April 2025 — after Elon Musk said on Saturday, August 29 that SpaceX would manufacture its own natural-gas turbine blades and vanes in-house, raising fears SpaceX could bypass specialized suppliers like Howmet. A trailing P/E above 57x heading into the session and a modestly risk-off market amplified the decline.
How much did HWM stock fall on Aug 31, 2026?
HWM fell 7.5% during the Aug 31, 2026 trading session.
What were the main drivers behind HWM's move?
Musk's SpaceX in-house turbine-blade announcement (primary); Stretched valuation; Modestly risk-off tape (secondary).