With the first-quarter 2016 earnings season getting underway, Atlanta-based Delta Air Lines Inc. DAL reported its financial numbers on Apr 14. The company’s results were quite a mixed bag, with earnings beating estimates and revenues missing the same. The below-par revenue performance was largely a result of the strengthening of the U.S. dollar, with foreign currency movements having an impact to the tune of $125 million. The terror assault in Brussels last month also dealt a blow. Meanwhile, a few developments grabbed headlines in the non-earnings front as well. Hawaiian Airlines, the wholly owned subsidiary of Hawaiian Holdings HA, managed to defend its top spot among U.S. carriers in terms of punctuality for the month of February. Moreover, the encouraging first-quarter 2016 operating margin guidance issued by low-cost carrier Spirit Airlines SAVE and a positive development on the labor front from United Continental Holdings UAL were other bullish updates. Read the last Airline Stock Roundup for Apr 13, 2016. Recap of the Past Week’s Most Important Stories 1. Delta’s first-quarter earnings (excluding special items) of $1.32 per share beat the Zacks Consensus Estimate by $0.03. Earnings also more than doubled, thanks to low fuel costs. Operating revenues came in at $9,251 million, marginally short of the Zacks Consensus Estimate of $9,285 million. Revenues declined 1.5% from the year-ago figure (read more Delta Air Lines Beats on Q1 Earnings, Revenues Slip). 2. The Air Travel Consumer Report unveiled by the U.S. Department of Transportation for Feb 2016 revealed that Hawaiian Airlines retained its top position with 91.9% of its flights touching down on time during the month. According to the report, 83.6% of flights operated by U.S. carriers (considered in the report) were on schedule in Feb 2016, reflecting an improvement from 81.3% recorded in Jan 2016 (read more Hawaiian Airlines Retains Most Punctual Airline Tag in US). 3. Shares of Spirit Airlines were positively impacted by the improved operating margin guidance issued by the company for the first quarter of 2016 (detailed results will be revealed on Apr 26).The company now expects operating margin at approximately 21.5%, which reflects an improvement from the previous view of 19% to 20.5%. The company attributed the improved guidance to better-than-expected revenues that was driven by strong ticket revenues per passenger. Adjusted cost per available seat mile, excluding fuel, is projected to decline approximately 2 % (the previous guidance had estimated a decline of 2.5% to 3.5%). The company expects fuel cost per gallon at $1.22 for the quarter (previous guidance: $1.25). The carrier expects its total revenue per available seat mile (TRASM) to decline approximately 14% on a year-over-year basis. The company also stated that its TRASM projection was better than expected, thanks to prudent revenue management. On a separate note, Spirit Airlines introduced non-stop flights to 14 new destinations and resumed service on 22 routes to facilitate summer travel. 4. Members of International Association of Machinists & Aerospace Workers or IAM, representing 30,000 workers (airport operations employees, contact center agents, storekeepers, maintenance instructors, central load planners, fleet technical instructors and related employees, and security officers) of United Continental Holdings, ratified a contract with the carrier, which guarantees them higher pay and improved working conditions. The deal will run through 2021. The tentative deal was inked earlier this year. Moreover, according to a Bloomberg report, the carrier is well on track to ink a deal with activist investors. Meanwhile, the company is facing opposition from some of its shareholders. Hedge funds PAR Capital Management, Inc. and Altimeter Capital Management, L.P, who collectively have a 7.1% stake in the company, are apparently dissatisfied with the company’s performance and have expressed their lack of faith in the current leadership and plan to nominate six candidates to the company’s board. Performance The following table shows the price movement of the major airline players over the past week and during the last 6 months: Company Past Week Last 6 months HA 4.03% 60.82% UAL 5.83% 4.13% GOL 11.11% -15.51% DAL -0.53% -6.54% JBLU 8.57% -13.39% AAL 5.16% -7.70% SAVE 14.61% 20.47% LUV 4.58% 13.90% VA 0.34% 61.00% ALK 2.52% 7.36% The table above shows that most airline stocks traded in the green over the past week with shares of Spirit Airlines appreciating the most (14.61%) on the back of its bullish guidance. Also, the NYSE ARCA Airline index rallied 4.25% over the past week to $96.42%. Over the past six months, majority of the airline stocks moved up with the NYSE ARCA Airline index gaining 3.97%%. Shares of Virgin America VA appreciated the most (61.00%) during the period. What's Next in the Airline Space? The coming week will be all about earnings in the airline space. Sector heavyweights like American Airlines Group AAL and Southwest Airlines LUV will reveal their first-quarter numbers over the next few days. While we expect the companies’ earnings to benefit from low fuel costs, the top line is likely to suffer on currency woes. Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report SOUTHWEST AIR (LUV): Free Stock Analysis Report DELTA AIR LINES (DAL): Free Stock Analysis Report HAWAIIAN HLDGS (HA): Free Stock Analysis Report UNITED CONT HLD (UAL): Free Stock Analysis Report SPIRIT AIRLINES (SAVE): Free Stock Analysis Report AMER AIRLINES (AAL): Free Stock Analysis Report VIRGIN AMERICA (VA): Free Stock Analysis Report To read this article on Zacks.com click here.