It's never a good time to do PR for the airline industry. Customers are fed up with escalating fees, while many airline employees seem to lack empathy both at the counter and in the cabin.

You would think the CEO of United Continental, Oscar Munoz, would recognize the public perception of his industry and he would have had a better plan in place than an "algorithm" to resolve overbooking issues that resulted in a passenger being dragged off of a United flight involuntarily. But that wasn't his biggest mistake in handling this crisis.

United and Munoz actually made three crucial mistakes that every executive should remember when dealing with disgruntled customers.

Strike one: United's CEO used tone-deaf language in referring to the incident.

In a video of the event that has spread around the internet like wildfire, the passenger is screaming as he's being removed forcibly from his seat and dragged down the aisle. That passenger had every reason to be upset. He paid for a flight and expected a service in return. This exchange for services shouldn't have ever been up for debate but somehow, Munoz found a way to bring it into question. His first statement used language to refer to the customer, whose face was bloodied in the process, and the three others who were bumped off the plane, like they were some kind of commodity:

"This is an upsetting event to all of us here at United. I apologize for having to re-accommodate these customers."

People make fun of "corporate speak" like synergy and circle back all the time but particularly in a crisis, words like "re-accommodate" have no place. They just come off as tone deaf and insensitive. This was arguably United and Munoz's biggest mistake. If other CEOs take away one lesson from this horrible incident, that should be it.

Strike two: Munoz should never have criticized the passenger.

Beyond his word choice, Munoz made a huge mistake in criticizing the passenger, saying he was "disruptive and belligerent." That may have been true but that's irrelevant. When the angry mob on the internet is sympathizing with that passenger and demonizing your company, the last thing you do is criticize that passenger. That just dug the hole for Munoz — and United — deeper.

Strike three: United could have prevented this from happening in the first place.

Every disgruntled customer can be "bribed." If an entire plane of customers refused to surrender their seats, then it was obvious United Airlines wasn't offering enough compensation for this inconvenience. The United crew should have been able to offer customers more to give up their seats — a first-class upgrade, or maybe a $1,500 voucher for a future flight.

It should be clear to United now that anything would have been worth the cost of preventing this crisis. They need to tweak their policies quickly and train employees to know how to civilly defuse an overbooked situation before it escalates into an epic disaster like this.

Before social media or phone cameras, few people would have seen or heard this passenger's cries as he was dragged off a United Airlines flight. I'm sure companies got away with this sort of behavior all the time. But, times have changed and one viral internet video can last forever on the internet, dent your stock and your reputation — maybe even permanently.

United and other companies should learn from this and train employees to always be on, always be on their best behavior — they are stewards of the company. They should assume that cameras are always rolling and behave accordingly.

United shares were down more than 4 percent on Tuesday as the incident and the company's handling of it rippled into the stock price.

I think the United board needs to think long and hard about this situation and how it reflects on Munoz's leadership. It may be time to demote him to coach — or remove him from the plane altogether.

Commentary by Mark Macias, head of Macias PR, a global public-relations firm, that has run media and branding campaigns for politicians, tech start-ups, financial firms, nonprofits and companies. He's also author of the book, "Beat the Press: Your Guide to Managing the Media." Follow him on Twitter @markmacias.

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