F-15 Silent Eagle demonstrator. Photo: Boeing. 

At the end of September, South Korea decided not to buy Boeing's (BA 1.51%) F-15 "Silent Eagle" and instead decided to seek a fighter with stealth capabilities. Then, at the beginning of October, Japan Airlines, or JAL, placed an order with rival European Aeronautical Defense and Space's (EADSY -4.02%) Airbus for the A350 instead of Boeing's 777X. Richard Aboulafia, industry analyst with the Teal Group, said this win "does more than damage Boeing's market standing; it damages the terms they'll get when they talk to Japan about an industrial role." 

Both of these losses are significant blows to Boeing. So, should investors be worried?

Favored to win, but loses
South Korea's decision is a shock to Boeing, as the F-15 was the only fighter that came in within budget -- only bids under budget can be considered, according to South Korean law. What's more, now experts believe Boeing has little chance of winning the next round of bidding because the F-15 offers only "passive stealth," which South Korean lawmakers and former military officials say is inadequate. This move is great news for Lockheed Martin's (LMT 1.23%) F-35, which is now favored to win, but it's a major loss to Boeing, as the defense contract is worth $7.7 billion. 

Boeing 777 fleet reaches 1 million flights under extended operations rules. Photo: Boeing.

In addition, when Boeing lost the JAL contract to Airbus -- estimated to be worth $9.5 billion (although discounts are likely) -- it not only lost its near wide-body monopoly in Japan, but it also jeopardized its manufacturing arrangements with Kawasaki, Mitsubishi, and Fuji. The Japanese government supplies subsidies to these manufacturers, which helps them win supply contracts with Boeing. That, in turn, helps Boeing by reducing upfront costs. However, Boeing's partnership with these companies came with the understanding that Japanese airlines would continue to buy Boeing's planes. That's no longer the case. As Aboulafia said, "This [Airbus] order will undercut the business case for the Japanese heavies. That's the real damage." 

Perhaps most concerning about this loss is, as the Seattle Times reported, that the 777x should have won the contract but lost because of management. The "787 and 777X should have won Boeing unquestioned dominance of all the key customers," Aboulafia said. "The problem is the management of Boeing. They have been incredibly passive about getting this program launched." 

Is it time to worry?
Of the two losses, the most concerning is the commercial loss. Boeing gets most of its revenue from commercial airline sales, and the loss of a key customer is never good news. That being said, I don't think it's time for investors to panic. According to its second-quarter report, Boeing's backlog remains incredibly strong, with nearly 4,800 commercial airplanes, valued at $339 billion. Plus, it delivered 306 commercial planes during the six months ending June 30, which is up from 287 from the same time last year.  

Moreover, total backlog as of June 30 came to $410 billion, which is up from $391 billion on March 31. Consequently, while Boeing's losses aren't great, and investors would do well to keep an eye on Boeing's management, I don't think it's time to bail on the company. However, going forward, if Boeing continues to lose key customers to Airbus (or any other manufacturer for that matter), it might be time to ask why, and re-evaluate your holdings.