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# Calculating takeoff speeds

By Murray Bourne, 18 Nov 2009

You are the pilot of a jet roaring down the runway approaching takeoff speed. Suddenly an emergency buzzer goes off, indicating a critical loss of oil pressure in one of the engines.

Do you keep accelerating, or do you try to stop the aircraft and stay on the ground?

Before a pilot begins the takeoff run, (s)he needs to know some important decision speeds. These include:

• VR - rotation speed, or the speed where the pilot pulls back on the control yoke and the front wheel leaves the ground
• V1 - takeoff decision speed, or the speed where the pilot is committed to go. It is safer to take off, rather than try to stop
• VRef - threshhold reference speed decision speed, or the speed crossing the runway threshhold, just before landing

Some of these are fixed for the aircraft type, while others depend on many variables, altitude, temperature, airplane configuration, weight, braking energy, and engine type. [See more on V Speeds.]

The following article is a "real-world math tutorial" from Kidwaresoftware.com:

Computing Airplane Takeoff Speeds (See the link towards the bottom - it's a zipped MS Word file. Update: The doc file is no longer available from that site.)

### 4 Comments on “Calculating takeoff speeds”

I'm interested in the takeoff speed tutorial, but unfortunately the Kidware site seems to have changed since your post. Do you know where I could get the word doc?

2. Murray says:

@Daniel: The ever-shifting Web...

I added a link to an Airbus document on aircraft takeoff speeds. Not a lesson like the original article, but may be of some use.

3. Philip Conrod says:

Hi,

If you are looking for the link for the following "Real World Math Tutorial" on our Kidware Software website it is now part of our Real World STEM Tutorial located under Chapter #11

Best Regards,
Philip

4. zac says:

@Philip: Thanks for the update. It's always a good idea to automatically redirect users to the updated page when making site changes.

For any readers who are interested in this, the resource now appears to be part of a (paid) software download.

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