The recent stock market crash caused many blue-chip stocks to plunge in value. Rolls-Royce (LSE: RR) and IAG (LSE: IAG) shares were among the worst-performing companies.Investor sentiment towards these businesses has soured in 2020 due to their exposure to the airline sector. The coronavirus pandemic effectively shut down the airline industry in March. It could also be many years before it recovers, according to analysts. 5G is here – and shares of this ‘sleeping giant’ could be a great way for you to potentially profit!According to one leading industry firm, the 5G boom could create a global industry worth US$12.3 TRILLION out of thin air…And if you click here we’ll show you something that could be key to unlocking 5G’s full potential…This suggests the Rolls-Royce and IAG shares could be set for several years of turbulence. However, both equities are currently trading at some of their lowest levels in recent history. This implies now may be a good time for long-term investors to buy into one of these world-beating operations. Engine problems IAG and Rolls-Royce both look attractive from a price perspective. Shares in the two companies are trading at multi-year lows, suggesting they may offer a margin of safety at current levels. But Rolls-Royce might struggle to return to growth in the medium term. While the company is one of the largest jet engine manufacturers in the world, it’s been struggling for years.The group’s woes started back in 2017 when problems were discovered in its flagship Trent 1000 engines, which power Boeing’s 787 Dreamliner. These issues forced airlines to ground their planes and Rolls had to fix the problem.Management believes the total cost of fixing the issue will be £2.4bn by 2023. As well as these severe issues, Rolls has also had to grapple with high costs and a lack of cash flow from the rollout of new engines. Typically, the group sells engines at cost and then makes money on the lifetime service contract. The pandemic came at a particularly bad time for the group. It was just starting to become cash flow positive, and management was forecasting substantial cash profits in the years ahead.These predictions are now defunct. It remains to be seen how long it’ll take the group to recover. As such, it could be many years before the Rolls-Royce share price returns to 2019 levels. IAG sharesIAG shares may be the better buy. Before the pandemic, the airline was already hugely profitable. To cope with the downturn, the firm aggressively cut costs and raised additional funding. These actions should help the group return to profit quickly when demand for air travel begins to pick up. Indeed, unlike Rolls, which is expected to remain loss-making, the City currently thinks IAG will return to the black in 2021. And if passenger activity returns to 2018/19 levels, investors buying IAG shares today could see substantial total returns.In these years the organisation made an average net profit of £2.1bn. By comparison, the group’s current market capitalisation is £4.1bn.These numbers indicate the stock is trading at less than two times normalised income, compared to the long-term average of five. To put it another way, IAG shares may have the potential to increase 250% if activity returns to 2018/19 levels. Therefore, IAG may be the better buy for discount-hunting investors today. I’m sure you’ll agree that’s quite the statement from Motley Fool Co-Founder Tom Gardner.But since our US analyst team first recommended shares in this unique tech stock back in 2016, the value has soared.What’s more, we firmly believe there’s still plenty of upside in its future. In fact, even throughout the current coronavirus crisis, its performance has been beating Wall St expectations.And right now, we’re giving you a chance to discover exactly what has got our analysts all fired up about this niche industry phenomenon, in our FREE special report, A Top US Share From The Motley Fool. Image source: Getty Images Stock market crash: should I buy Rolls-Royce or IAG shares? See all posts by Rupert Hargreaves Enter Your Email Address Click here to claim your copy now — and we’ll tell you the name of this Top US Share… free of charge! I would like to receive emails from you about product information and offers from The Fool and its business partners. Each of these emails will provide a link to unsubscribe from future emails. More information about how The Fool collects, stores, and handles personal data is available in its Privacy Statement. 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Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.