When the smoke clears, the group sits back down and learns that six to eight passengers can go through the door in the time it takes one passenger to go through the tiny over-wing exit. Seconds count. In the simulator, anyone who hesitates gets a stern lecture. In real life, they're pushed out the door, down the slide by a flight attendant.
Clubb explains that the key to survival is getting into the proper brace position: Bend forward as far as possible, keep your head down. Place your feet flat on the floor and slide them back.
Your dominant hand goes on the back of your head. Protect that hand by placing the other hand over it. Do not interlock fingers. The goal is to ensure that the bones in the stronger hand aren't broken so you can eventually unbuckle the seatbelt.
Will members of the class ever use the training? Each day, 8.3 million people around the globe step aboard some 93,500 flights. They almost always land safely. In the past decade, there have only been 138 crashes worldwide that had fatalities, according to aviation consultancy Ascend.
Read MoreCabin crew ... in lingerie?
The majority of crashes occur during takeoffs and landings and there are often survivors.
"The likelihood is that you are never going to have to do it in a real life situation. But knowing now that you could do it, just gives you a bit more confidence," says participant Sarah Barnett, who frequently flies in her job marketing vacation destinations. (Classes can be booked here.)
The course also aims to give the fliers confidence in the people at the front of the plane.
"The two guys at the front of your airplane are probably the most highly regulated and checked professionals you'll find anywhere—certainly more than your doctor or your lawyer or your accountant," says British Airways pilot Martin Hockfield.
Hockfield tells the class that pilots come in twice a year for testing. In a simulator, they practice takeoffs with engine failures or landing after a loss of hydraulic pressure. It's like taking a driving test every six months - in a broken car.