VNE and Speed Limitations at Altitude


Nov 21, 2007
Hello, all! I'm new here and would like to learn about physics of flight to help clear up a
debate between friends.

Our discussion revolves mostly around flight limitations at certain altitudes, and the physical
limitations of aircraft.

We're using either of the following airplanes in our analysis: DC10, 707, 757, 767

My questions are:

1. What is the maximum landing speed of either plane in Knots, or MPH?

2. What is the maximum approach speed of either plane in Knots, or MPH?

3. VNE - Velocity do not exceed. What is a typical VNE at 1000 feet altitude, and
how much (if any) can you exceend VNE without stressing the structure of the aircraft?

4. Effects of atmospheric pressure and altitude on speed. Is an airplane able to fly
as fast at sea level as it can at 35,000 feet? If not, how much slower can we expect
to fly at sea level?

I wont give my opinions, however I will say that I believe:

1. Max landing speed for either of those planes is approximately 150-200 knots

2. Max approach speed for either of those planes is apporximately 150-200 knots

3. VNE may be exceeded , however not recommended. VNE could never be doubled safely
at any altitude.

4. No, an aircraft cannot fly as fast as sea level because of aero drag due to atmospheric
pressure. For every 1000 ft. of decent, subtract about 5 MPH?

Thanks for your time!