Doppler Light Lab
I was on a 767 airliner yesterday and noticed that there was a split-second between the time I pressed the switch for the overhead lamp and the time the lamp actually came on. What is this period of time called and what happens during it?
———- from David Coursey ofSan Mateo, CA
You experienced what scientists call Doppler Light Lag, which happens on all the bigger airplanes. To compute the amount of Doppler Light Lag, take the seating capacity of the airline you’re on, multiply by the speed at which it’s cruising, usually 500 miles per hour, and then divide by the cost of your ticket, in dollars. If you’re using a frequent flier ticket, take the number of miles used to purchase that ticket and divide by forty. You’ll see that the more expensive your ticket, the smaller the lag time between pressing the switch and the light turning on. If your ticket cost over a thousand dollars and the airplane is taxiing, the Doppler Lag will be so short it’s unnoticeable. I know it’s not much of a perk, but then all the romance and sense of luxury went out of flying years ago.
You experienced what scientists call Doppler Light Lag, which happens on all the bigger airplanes. To compute the amount of Doppler Light Lag, take the seating capacity of the airline you’re on, multiply by the speed at which it’s cruising, usually 500 miles per hour, and then divide by the cost of your ticket, in dollars. If you’re using a frequent flier ticket, take the number of miles used to purchase that ticket and divide by forty. You’ll see that the more expensive your ticket, the smaller the lag time between pressing the switch and the light turning on. If your ticket cost over a thousand dollars and the airplane is taxiing, the Doppler Lag will be so short it’s unnoticeable. I know it’s not much of a perk, but then all the romance and sense of luxury went out of flying years ago.