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What is slowest speed a commercial jet can travel?

  1. May 14, 2013 #1
    At Stewart airport in Newburgh New York a small commercial commuter jet leaves and lands in Philadelphia, Pa one hour later. The total distance is about 150 miles. Can small commercial jets travel at an average speed of only 150 miles/hour?
  2. jcsd
  3. May 14, 2013 #2


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    It can travel at zero mph if it takes off and lands at the same airport. ;)

    In general, swept wing jets can fly as slow as 150 mph, but usually that is with flaps out, in a landing configuration. The aircraft is not expected to operate that way other than for takeoff or landing. Cruise is usually about 3x faster, but that also depends on altitude. Speed while climbing is less, usually about 250-300mph.
  4. May 14, 2013 #3


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    Do you mean takes off at t=0 and touches down one hour later? Or do you mean departs and arrives?

    If you are looking at departure and arrival times there may be half an hour of pushback, queuing and then taxiing to the runway for takeoff and then taxiing to the gate on arrival.
  5. May 14, 2013 #4
    To elaborate on what has already been stated:

    The slowest speed an aircraft can safely travel is (just above) its stall speed. For most smaller commercial jets the stall speed with flaps up is going to be around 150-160 KAIS and with flaps down around 120 KAIS.

    The cruising speed of the aircraft is typically going to be calculated to optimize fuel performance at a given altitude and for smaller commercial aircraft that is going to be in the 400-450 KAIS range for a 30,000+ft cruise. If the trip is only 150 miles you might only go into the 20,000ft range.

    As has already been pointed out, if you are going of listed departure/arrival times then that one hour is broken up like this: 12 minutes between leaving gate and takeoff, 15 minutes of climb, 5 minutes of cruise, 20 minutes of descent to landing, and 8 minutes to taxi to the gate at arrival.

    So in a 1 hour "flight" only 5 minutes was spent at the cruise speed and only 40 minutes was spent in the air. And that is a little generous, from my experience the airlines budget 30 minutes of listed flight time for time spent on the ground.
    Last edited: May 14, 2013
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