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Dr. Kim Mulvihill ReportingThe Navy's Blue Angels were in San Francisco recently for fleet week and they had an extra passenger; KSL’s Doctor Kim Mulvihill was selected to fly with the precision pilots.
Following, Dr. Kim Reports why not everyone is fit to fly at nearly twice the speed of sound.
It was an incredible opportunity, a chance of a lifetime. To help get ready for the flight I talked with Doctor Jim McGreevy from the University of Utah. He flies every week and agreed to give me the inside scoop.
Doctor Jim McGreevy is a flight surgeon with the reserve squadron at hill air force base.
Dr. Jim McGreevy, Flight Surgeon: “My job with the Air Force is to get to know the air crew and to monitor their health.”
He flies every week in an F-16. He says it's the air force version of the F-18's flown by the blue angels.
Dr. Jim McGreevy, Flight Surgeon: "If someone has a cold they can't fly. If they've had dental work they shouldn't fly. The environment is so harsh and unforgiving."
If you have gas trapped in a tooth and go up in altitude and lose pressure in the cabin it could cause such pain as to make it difficult for someone to land the airplane."
The F-18's can reach speeds of just under mach 2, almost twice the speed of sound. The sense of speed and gravitational force is most noticeable when you're making a turn.
Dr. Jim McGreevy, Flight Surgeon: "All the forces go from your head straight down to the seat of your pants, and you feel like you're being pushed into the seat and that's the hard G force that you'll have to get used to. And the reason you have to get used to it is it tends to drain the blood out of your brain."
First you lose your vision, then sensation, and eventually you lose consciousness. To off-set those gravitational forces all fighter air crews are taught a straining maneuver.
Dr. Jim McGreevy, Flight Surgeon: “Before you start the turn you take a big gulp of air and close your glottis and just squeeze as hard as you can for three seconds, and then relax and open your mouth and let the air blow in and then squeeze another three seconds. And that squeezing actually forces the blood back up into your head."
Restrictions on flying have changed over the years. In the past you couldn't fly with a joint replacement, but today there are several pilots who have had hip replacement surgery. Pilots are grounded during pregnancy, but some medical conditions like a heart attack will keep a pilot on the ground permanently.