SpaceX's winning streak went up in a ball of fire and a puff of smoke in September. Image source: U.S. 45th Space Wing.

Americans love to cheer for an underdog. So let me preface today's column with a hearty three cheers for SpaceX -- the first company to land an orbital rocket back on Earth on its own tailpipe, the first to land a rocket intact at sea, and -- potentially, one day -- the company that will put mankind on Mars. The fact that one small private company, backed by one visionary (and his money), has managed to accomplish so much in such a short period of time (SpaceX is less than 15 years old), and against such entrenched competition from the world's aerospace giants, seems nothing less than extraordinary.

But now, let's get real -- and take a really hard look at SpaceX's safety record.

Spaceflights for cheap...

SpaceX has shaken up the space industry, and not just here in America, where its $62 million rocket rides are cutting off Boeing (BA -1.91%) and Lockheed Martin (LMT 0.22%) at the knees (their United Launch Alliance joint venture charges twice that). Over in Europe, Airbus (EADSY 1.22%) subsidiary Arianespace says that SpaceX is really the only space company they're worried about. In Russia, Roscosmos is flabbergasted at the Walmart-like everyday low prices that SpaceX advertises.

What's even more amazing is that for a while there, SpaceX was doing a pretty good job of beating its competitors at their own game. Up until June 2015, SpaceX had strung together 20 straight successful space launch missions in a row before one of its rockets blew up. And even after stumbling when its CRS-7 mission exploded midflight, SpaceX quickly regained its footing, returning to flight in December last year and sticking its first landing on Earth in the process.

Nine successful launches later, though, SpaceX suffered yet another failure. On Sept. 1, a Falcon 9 rocket preparing to send an Israeli telecommunications satellite into orbit exploded on its pad during pre-flight testing. Ever since, SpaceX has been sending out plaintive tweets asking space fans to send "audio, photos or videos of our anomaly" in hopes they will prove "useful for investigation" of the as-yet unsolved mystery.

And SpaceX's winning streak has reverted to zero.

"Cheap" at a price

Now compare that to the records at ULA and Ariane, SpaceX's two chief rivals in space launch. Last week, ULA successfully launched the NASA OSIRIS-REx mission aboard one of its Lockheed-built Atlas V rockets. Its mission: to extract mineral samples from an asteroid and return them to Earth for study.

OSIRIS-REx was ULA's 111th straight successful launch, counting missions sent up by both Atlas V and Boeing-built Delta IV launch vehicles. Since ULA was formed in December 2006, it has yet to suffer a single mishap on any of its big rockets -- a near-10-year streak of unbroken success.

Airbus' record at Ariane is nearly as stellar, and in some respects even better than ULA's. The company's previous launch vehicle, the Ariane 4, racked up 74 straight successes before its retirement in February 2003. Its current vehicle, the Ariane 5, has flown without a single incident since its inauguration in 2003. Ariane 5's record of 73 straight successes stands within a whisker of beating Ariane 4's record -- and Ariane 5's history of 13 straight years of flight without incident has already outpaced that of ULA (admittedly, mostly because ULA hasn't yet existed for 13 years).

Cheapest... and least reliable?

If SpaceX keeps blowing up its rockets at the rate of one per year, it's going to be awfully hard for the company to catch up to the rocket launch leaders. But that's more of a marketing problem for SpaceX. Here's where it morphs into a business problem:

Currently, SpaceX is the cheapest launch provider in the West. At a base launch cost of $62 million for a Falcon 9, SpaceX launches rockets at a price per ton roughly half that of its nearest competition. And that big price disparity has given SpaceX an enormous advantage in bidding for launch contracts.

In just three years, however, Boeing and Lockheed plan to field a new and improved launch vehicle called the Vulcan, which could shrink SpaceX's price advantage considerably from 2019 on out. One year later, Airbus and Ariane will introduce their new and improved rocket called the Ariane 6, which could drop their launch cost to within just 11% of SpaceX's for very large payloads by 2020.

At that point, space launch customers will face an interesting dilemma: Do they pinch pennies and save 11% by launching with SpaceX, despite its checkered history of rocket reliability? Do they opt for Ariane's long record of reliable launches, and pay a bit more? Or do they pay even more for ULA's even longer record of safe launches? (And what happens when we move away from robotic spaceflights, and start stuffing humans into the capsules again)?

Time will tell. Meanwhile, if SpaceX wants to keep winning customers and stealing market share from its rivals, it's time to start building a record of reliability of its own. With any luck, by the time 2019 and 2020 roll around, its customers won't think to ask this question -- and SpaceX can get back to doing what it does best: Competing on price.