Alcoa significantly changed its near term aerospace outlook. Image source: Getty Images Alcoa Inc's (NYSE: AA) status as the bellwether of the industrial sector remains undiminished. As such, the company's second quarter earnings presentation contained a host of useful information for investors anticipating the current earnings season. Let's take a closer look at what Alcoa's management said. Alcoa's end market outlook The best way to look at matters is to compare the latest end market growth outlook with outlooks given in previous quarters. Given the deterioration in the overall growth outlook of most economists in 2016, Alcoa's report makes pretty good reading. The bolded figures in the table show where Alcoa has made changes to its outlook. Alcoa Business Segment guidance At Q4 2015 At Q1 2016 At Q2 2016 Aerospace 8% to 9% 6% to 8% 0% to 1% Automotive 1% to 4% 1% to 4% 1% to 4% Heavy Duty Truck and Trailer (3%) to 1% (4%) to 0% (4%) to (1%) Packaging 1% to 3% 1% to 3% 1% to 3% Building & Construction 4% to 6% 4% to 6% 4% to 6% Industrial Gas Turbine 2% to 4% 2% to 4% 2% to 4% Data source: Alcoa Inc presentations. Packaging (all regional outlooks remain the same) is a relatively stable industry -- so no surprises at the maintenance of outlook. However, the rest of Alcoa's end markets tend to be quite cyclical. The consistency of the industrial gas turbine outlook will please General Electric Company (NYSE: GE) investors, particularly as Alcoa CEO Klaus Kleinfeld specifically referenced the strength in the heavy duty gas turbine market -- where General Electric's new H-class turbine is dominating new sales. Building & construction and trucking There have been question marks on global building & construction markets (particularly in the US and China) but Kleinfeld kept global guidance the same with only some minor adjustments to North America (guidance for 4% to 5% growth from 4% to 6% previously) and China still set to grow 3% to 5% -- that's good news for elevator (Otis) and climate control sales at United Technologies's (NYSE: UTX). The heavy duty truck & trailer outlook continues to comprise a sharply falling North American market (forecast to be down 28% to 26%) while the EU and China are set for modest growth. Automotive The outlook for the automotive sector in 2016 has been hotly debated, with U.S. vehicle sales having peaked in 2015, and uncertainties over underlying demand in China after the initial impact of the tax incentives on small vehicles starts to fade. No matter, Alcoa's global outlook has been consistent throughout 2016, with a slight strengthening in the EU and China balanced by a slight weakening in the outlook for North America. All about aerospace It's time to point out the elephant in the room. As you can see above the aerospace outlook was significantly reduced, but don't panic. According to Kleinfeld it isn't due to any fundamental weakness in the industry, rather a set of transitory issues which are likely to push growth into 2017 -- Kleinfeld expects at least 10% growth next year in aerospace. Some of the Issues he mentioned include: A host of new aircraft models is creating a "careful ramp-up" in production as new technologies are introduced Orders for legacy aircraft are lower due to customers ordering/considering new models Delays in engine deliveries on some planes, notably the Airbus A320neo Bifurcation in market as engine components are seeing good growth (new technologies) while airframe components will see demand "filled basically through destocking" The first two issues are known to the market, but based on how Alcoa's forecasts have changed it's possible that there could be some near term disappointment in the coming earnings season from some aerospace suppliers -- whether the market will take the longer term, positive, view is another question. The engine issues largely relate to United Technologies (Pratt & Whitney) new geared turbofan engine. Pratt & Whitney's management arguing that the problems have been fixed -- Alcoa's Kleinfeld didn't specifically refer to the geared turbofan, but he also said technical engine problems "are solved." However, it's not clear how these delays may impact airlines willingness to choose Pratt & Whitney's geared turbofan engine over CFM International's (a joint venture between General Electric Company and Safran) Finally, the bifurcation between engine components (good) and airframe components (bad) suggests a mixed near-term aerospace outlook for major players like Honeywell, United Technologies, and General Electric Company who supply a range of products on planes. However, a major airframe component (fasteners) like KLC Inc may report disappointing results. Looking ahead Under the circumstances Alcoa's outlook is pretty positive for the industrial economy. However, don't be surprised if the coming earnings season produces some surprising guidance from aerospace companies. Provided you agree these issues are transitory in nature, any near term earnings disappoints could create some decent buying opportunities in the sector. A secret billion-dollar stock opportunity The world's biggest tech company forgot to show you something, but a few Wall Street analysts and the Fool didn't miss a beat: There's a small company that's powering their brand-new gadgets and the coming revolution in technology. And we think its stock price has nearly unlimited room to run for early in-the-know investors! To be one of them, just click here.Lee Samaha has no position in any stocks mentioned. The Motley Fool owns shares of General Electric. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.