Just how safe are the skies for air travelers?

If you were packing a firearm or a hand grenade or boxcutters as you went through a TSA airport-security checkpoint, you might as well have relaxed: There was a 95 percent chance the TSA would have failed to discover the contraband. That’s right, the TSA’s success rate in detecting banned carry-on items was a paltry 5 percent.

Those were the results of a recent test of the TSA’s security-screening operation at Minneapolis-St. Paul airport, conducted by the TSA itself. According to Fox9 Minneapolis-St. Paul, agents posing as passengers were successful 17 out of 18 times in sneaking explosives, weapons, and drugs past security screeners.

The report notes that in April 2016, a similar test of the TSA’s Minneapolis security operation found that screeners failed to identify nine out of 12 banned items.

Of course, it’s unclear whether and to what extent those results can be extrapolated to other U.S. airports. But the TSA’s procedures at Minneapolis-St. Paul should be the same as its procedures at JFK, and LAX, and Atlanta, and Chicago, and so on. If the failure rate was 95 percent at Minneapolis, there’s no obvious reason to expect a significantly different result at other airports.

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Travelers endure the inconvenience, discomfort, and lost time in security screening lines on the assumption that their forbearance is in the service of a greater good: enhanced security. To find that the promised security is more illusory than real is troubling at best, infuriating at worst.

The traveling public has a right to know how the TSA is performing its principal task, that of keeping air transportation safe. No doubt the TSA is uncomfortable having its poor performance brought to the public’s attention. In fact, what’s needed is more transparency, not less. A first step might be to have the TSA’s success rate in identifying banned materials regularly monitored by an independent agency, and the results made public.

Until then, air travelers have every reason to wonder just how safe the skies really are.

Reader Reality Check

Disturbing, right?

After 20 years working in the travel industry, and almost that long writing about it, Tim Winship knows a thing or two about travel. Follow him on Twitter @twinship.

This article first appeared on SmarterTravel.com, where Tim is Editor-at-Large.