As the first quarter earnings season gets into full swing, notable aerospace and defense contractors like Textron Inc. TXT and Rockwell Collins Inc. COL have kick started with impressive beats.However, the bourses have a different story with more downs than ups for most of the major defense companies over the past five trading sessions. The S&P 500 Aerospace & Defense (Industry) index declined 0.11% last week.Earnings releases apart, the other important highlights include the approval of the U.S. government to a deal that would allow U.S. firms to sell advanced medium-range AIM-120D air-to-air missiles to Australia, a key ally in the Asia-Pacific region.(Read Defense Stock Roundup for Apr 19, 2016 here.)Recap of the Week’s Most Important Stories1. Defense contractors Lockheed Martin LMT, Northrop Grumman NOC, Raytheon Integrated Defense Systems Advanced Technology Programs RTN, EOIR Technologies, SI2 Technologies, S2 Corp., Sea Corp., Leidos LDOS, Rockwell Collins, Physical Optics Corp., and TiCom Geomanics have each been awarded a multiple award contract from the U.S. Navy. The maximum value of all the 12 contracts under this Electromagnetic Maneuver Warfare Command and Control program is $800 million and work is expected to be completed by Apr 24, 2021.2. On Monday (Apr 25), the U.S. government approved a deal that would allow U.S. firms to sell air-to-air missiles and support equipment to Australia, its key ally in the Asia-Pacific region. The Defense Security Cooperation Agency (“DSCA”) said in a statement after notifying Congress of the possible deal.The Australian government has requested up to 450 advanced medium-range AIM-120D air-to-air missiles from Raytheon. The AMRAAM missiles will arm the Royal Australian Air Force's F/A-18, E/A-18G and F-35 aircraft, the DSCA statement said.3. Diversified U.S. conglomerate Textron Inc. reported first-quarter 2016 numbers with both its top and bottom line beating estimates. Earnings and revenues also increased 19.6% and 4.2% from the year-ago quarter, respectively. This was primarily due to higher contribution from Textron Aviation, Textron Systems and Industrial. Bell segment revenues were essentially flat at $814 million with the year-ago level of $813 million.Textron maintained its 2016 earnings per share guidance in the range of $2.60 to $2.80 (read more: Textron Beats on Q1 Earnings & Revenues, Keeps View).4. Rockwell Collins Inc. also turned up with a positive earnings surprise in its financial results for second-quarter fiscal 2016 ended Mar 31, 2016. Reported earnings rose 6.6% year over year. However, revenues missed the consensus mark and dipped 2.2% year over year due to lower sales across Commercial Systems and Government Systems.Rockwell Collins reaffirmed its earnings guidance for fiscal 2016 in the range of $5.45−$5.65 per share on total revenues of $5.3−$5.4 billion (read more: Rockwell Collins Q2 Earnings Top, Keeps FY16 View).5. Orbital ATK Inc. OA has been awarded a modification contract, worth $121.4 million, from the U.S. Navy for the conversion of U.S. government-provided AGM-88B high-speed anti-radiation missiles into 145 full-rate production Lot 5 advanced anti-radiation guided missile all-up-rounds and 12 captive air training missiles for the Navy and the government of Italy.Work is expected to be completed in Sep 2018.PerformanceVolatility was rampant in last week’s trading sessions with most of the defense stocks facing losses. Rockwell Collins lost the most followed by Boeing BA.The past six-month picture is peppered with more gains than losses. Northrop Grumman gained the most while Boeing was the biggest loser.The following table shows the price movement of the major defense players over the past five trading days and during the last six months. Company Last Week Last 6 months LMT -0.09% 3.96% BA -1.45% -9.49% GD 0.07% -6.64% RTN -0.60% 8.55% NOC -0.43% 12.28% COL -4.76% 3.99% TXT 2.47% 0.54% LLL 0.52% 8.88% What’s Next in the Defense World?Lockheed Martin will release first-quarter earnings today.Boeing, Northrop Grumman, General Dynamics Corp. GD and L-3 Communications Holdings Inc. LLL will release their first quarter numbers on Apr 27.Raytheon will report first quarter results on Apr 28 and Spirit AeroSystems Holdings, Inc. SPR on Apr 29.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 NORTHROP GRUMMN (NOC): Free Stock Analysis Report BOEING CO (BA): Free Stock Analysis Report GENL DYNAMICS (GD): Free Stock Analysis Report LOCKHEED MARTIN (LMT): Free Stock Analysis Report ROCKWELL COLLIN (COL): Free Stock Analysis Report SPIRIT AEROSYS (SPR): Free Stock Analysis Report TEXTRON INC (TXT): Free Stock Analysis Report RAYTHEON CO (RTN): Free Stock Analysis Report L-3 COMM HLDGS (LLL): Free Stock Analysis Report LEIDOS HOLDINGS (LDOS): Free Stock Analysis Report ORBITAL ATK INC (OA): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research