Emergency plane evacuations
Before I retired, I tested the materials that went into construction projects. This was done to very specific standards — concrete was placed in a standard sample cylinder by a standard method, and then it was broken using a standard machine. This standard did not look like the actual structure being built — but because it was standardized, it accurately reflected the properties of the materials being used.
Which brings me to U.S. Sen. Tammy Duckworth’s op-ed in the Dec. 30 Tribune (“FAA should use real-life conditions for evacuation rules”). Her opinion piece says the Federal Aviation Administration did not use “real-life conditions” while running simulations for emergency evacuations of aircraft.
Simulations and testing have to be done to repeatable standards. To test different seating arrangements, the passenger consist has to be the same across all the test runs. This does not have to be real life — If a group of able-bodied people can escape an aircraft in under 90 seconds, then a larger, mixed ability group should be able to escape in, say, six minutes.
Say you wanted to run tests using a more representative group. How many over 60 people would you select? How many babies? How many wheelchair users? Where would you seat them? (It has to be consistent.) Random groups would give random results, and the test would be useless.
I wonder if Duckworth talked with the engineers running these tests, to ask how solid the data they got was. If anyone knows how to improve aircraft egress methods, it would be them — and cabin attendants.
Also, the FAA always looks at real-time emergency evacuations to see what does occur under real-time conditions. It turns out that about a third of passengers try to take their carry-ons off with them despite instruction not to, and half are using their phones to video the event.
Duckworth appears to be trying to appeal to her constituents who think they know more than trained engineers, but she should let engineers do what they know how to do. — C.H. “Chas” Hague, Des Plaines