Flying with a tail wind ups ground speed
Question: I recently flew from Honolulu to Atlanta on a 757, and the tail wind was so strong, upward of 200 mph, that it took only 7 hours to make that distance. I used the flight tracker to see at one point we were traveling 705 mph. How fast can a passenger plane safely travel?
– Brent Butler, Indianapolis
Answer: There is not a limit on the ground speed an airplane can fly. The limitation is the airspeed or Mach (percentage of the speed of sound).
If an airplane is enjoying a strong tail wind, there is no additional stress on the airplane due to the increase in ground speed.
Q: This may be a dumb question, but how do you tell if you have a tail wind or head wind when at a high altitude in a big jet? Can you feel it in the controls, or is there an indicator or weather report?
– James, Colorado Springs, Colorado
A: Modern jets have wind readout on the navigation displays. The easy way is to check the ground speed versus the true airspeed.
If the ground speed is greater, then there is a tail wind. If it is lower, then there is a head wind. You do not feel any difference in control forces either way. Q: Can planes take off with a tail wind? If so, is there a maximum limit?
– Roger Rodrigues, Burr Ridge,
Illinois A: Yes, you can take off with a tail wind. However, careful calculation of the takeoff performance must be done. The maximum limit is usually 10 knots.
John Cox is a retired airline captain with US Airways and runs his own aviation safety consulting company, Safety Operating Systems.