The September 11 attacks have served as a lasting reminder of the importance of the U.S. aerospace and defense industries, from aviation safety and security to military readiness and national defense.

As we commemorate the 25^th anniversary of 9/11, investors may also take note of the strong operating momentum across the aerospace and defense sector.

ATI Inc. (ATI Quick QuoteATI - Free Report) ), Ducommun (DCO Quick QuoteDCO - Free Report) ), Innovative Aerosystems (IA Quick QuoteIA - Free Report) ), formerly Innovative Solutions & Support, and Loar Holdings (LOAR Quick QuoteLOAR - Free Report) ) are particularly intriguing, with all four stocks currently sporting a Zacks Rank #1 (Strong Buy) amid favorable earnings estimate revisions.

ATI Inc. – ATI

Stock Price: $198

Headquartered in Dallas, Texas, ATI produces highly engineered specialty materials, alloys, forgings, and components used extensively in commercial jet engines, airframes, and defense applications.

Business is booming, with Q2 sales rising more than 10% year over year to $1.26 billion as aerospace and defense revenue increased 13%. Adjusted EBITDA jumped 37%, while ATI's backlog reached a record $4.4 billion, up 18% YoY. Management also raised its 2026 adjusted EPS guidance to $4.90-$5.18 (+50% YoY growth), providing a strong catalyst for higher analyst estimates.

Ducommun – DCO

Stock Price: $172

Based in Costa Mesa, California, Ducommun supplies complex electronic and structural systems and components for commercial aircraft, military platforms, space programs, and other advanced applications.

Ducommun delivered record Q2 revenue of roughly $224.5 million, up 11% YoY, while adjusted quarterly EPS of $1.18 crushed estimates by more than 25% and soared 34% from $0.88 per share a year ago.

Gross margin reached a record 28%, adjusted EBITDA climbed 21%, and remaining performance obligations (RPO) hit an all-time high of $1.2 billion.

Innovative Aerosystems – IA

Stock Price: $19

Headquartered in Exton, Pennsylvania, Innovative Aerosystems—formerly Innovative Solutions & Support—develops advanced avionics for commercial, business, and military aircraft, including flight displays, navigation systems, autothrottles, and flight-control technologies.

Innovative Aerosystems most recently reported fiscal Q3 sales of $26.7 million, which increased nearly 11%, while gross margin surged to 51.7% from 35.6%. Furthermore, Q3 adjusted EPS more than doubled to $0.33, and nine-month free cash flow jumped 155% to $12.3 million. The company also finished the quarter with a record $83 million backlog.

Loar Holdings – LOAR

Stock Price: $66

Headquartered in White Plains, New York, Loar designs and manufactures niche, mission-critical aerospace and defense components used across commercial aircraft, business jets, and military platforms.

Loar posted another record quarter in Q2, with sales surging 39% to $171.6 million and adjusted EBITDA jumping 47% to $69.4 million. Adjusted EBITDA margin topped 40%, while adjusted EPS rose 23% YoY to $0.38. Management subsequently raised its 2026 adjusted EPS outlook to $1.32-$1.36 (+26% YoY growth).

Bottom Line

While 9/11 remains first and foremost a day of remembrance, it also underscores the enduring importance of aviation security, aerospace technology, and national defense.

From ATI's massive backlog to Ducommun's rising margins, Innovative Aerosystems' expanding profitability and Loar's rapid growth, these four Zacks Rank #1 (Strong Buy) stocks are backed by operating momentum that has translated into increasingly bullish earnings estimates.