Julian537

My Feedback: (9)

does someone have doppler software to measure speed?

Can someone measure the speed of this plane.

http://www.youtube.com/watch?v=ZVs4NEtYnM4

I am interested to know how fast they are going.


Great video btw!

Mike Connor

My Feedback: (5)

I only checked one of the better runs at the 2 minute mark and got 170 mph.
You can download the software at http://www.sprut.de/electronic/soft/scope.htm

Julian537

My Feedback: (9)

Thanks Mike
170 is not to bad!

TXKflier

I figure it's closer to 190 mph..

I measured the speed using Creative Wave Studio after setting my Creative Surround Mixer to the "What U Hear" record mode. Once I had recorded the sound in Wave Studio, I selected the area I wanted to measure and zoomed in until I could see the pulses. For this plane, I could see them best at the 1:2 setting. For other planes, it'll depend on the rpm of the engine. To make the measurement, I click and hold on the pulse closest to the right side of the screen, drag the mouse to the left until I get to the pulse nearest the left side on the screen, and then let go. There's a box in the lower right corner of Wave Studio that tells you the length of time that you just highlighted. I counted the pulses starting with the second one and ending with the last one. I divided the number of pulses by the amount of time which gave me the frequency. On the approach side, I measured 28 pulses in 0.043 seconds and for the departure, I measured 17 pulses in 0.043 seconds. The corresponding frequencies are 651 Hz and 395 Hz. According to the spreadsheet published by Harry Lagman, that gives an actual engine rpm of 29,500 and a ground speed of 189 mph.

I've attached a screen capture of measuring the frequency in Wave Studio.

Lynn

Mike Connor

My Feedback: (5)

It just goes to show you that the more effort you put into it the faster you go.
Here is a capture of my WaveOScope screen. It was one of the easier files to read.
I thought I picked one of the faster runs but maybe not.

Troy-RCU

My Feedback: (1)

Yah, it's certainly closer to 190mph. That's an F3D pylon ship and they are usually in the 190's on course.