Airline stocks took flight Monday, as some encouraging comments from Dr. Anthony Fauci regarding the omicron variant's severity helped calm investor fears regarding potential future travel restrictions. The U.S. Global Jets ETF /zigman2/quotes/207744796/composite JETS -2.43% jumped 7.2% in midday trading, toward its biggest one-day gain in 13 months, with 43 of 50 equity components gaining ground. The ETF has now gained 11.3% since closing at a 13-month low on Dec. 1. Among the best performing and most-active U.S.-listed components, shares of United Airlines Holdings Inc. /zigman2/quotes/205037281/composite UAL -2.87% climbed 11.1% in midday trading, was the S&P 500's /zigman2/quotes/210599714/realtime SPX -1.89% second-biggest gainer and was on track for the best day since Nov. 9, 2020. Among other more-active U.S. air carriers, shares of American Airlines Group Inc. /zigman2/quotes/209207041/composite AAL -2.74% rallied 10.2%, Delta Air Lines Inc. /zigman2/quotes/200327741/composite DAL -2.52% ran up 8.6%, Southwest Airlines Co. /zigman2/quotes/201071949/composite LUV -2.19% rose 5.3% and JetBlue Airways Corp. /zigman2/quotes/207639051/composite JBLU -3.77% jumped 7.6%. The stocks' gains come amid a broad market rally, with the S&P 500 up 1.2%.