How to get air speed, which sensor to use? I want to measure the airspeed on a flying vehicle and get the data with arduino. Note that, there will not be any control mechanism on the flying object, it will be flying mechanicaly/passively, I mean no flight controller or something like that will be present. 

However, I could not understand whether there is a sensor to measure the airspeed directly or is airspeed something you analyze by using other datas(temperature, pressure etc.)

I saw there are sensors which are sold as "airspeed sensor" however it is not so common that I cannot find examples in which the incoming data is shown.

Anybody ever experienced with this issue may lighten me.

Thanks in advance.
Typically you want to use Pitot tube sensor