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Sporally
2009-Jun-27, 10:05 AM
I just watches this Apollo 11 launch video with data and couldn't make them make any sence.

http://www.youtube.com/watch?v=F0Yd-GxJ_QM&feature=related

We have velocity and altitude. First problem is that around 2 minutes into the video the velocity is 2,000m/s but its altitude is only increasing by around 1,000m/s - i figured this has to do with the actual altitude and the downrange data. However, if you're listening to the commentary giving you data information in miles you'll see at times that he is actually saying things that just doesn't fit with the data on the screen. Is this because it is homemade data?

For instance, he says its velocity is 2,000 feet/s at around velocity = 500m/s. Can anyone tell me what is wrong here?

mugaliens
2009-Jun-27, 10:53 AM
Sounds like a case of the video editors splicing the audio into visually appealing clips, rather than temporally correct clips.

Mike_c130
2009-Jun-27, 12:24 PM
As to your first remark, the reason that the altitude is not increasing as fast as velocity would seem to indicate is that the rocket is not travelling straight up, or even close to it. The vehicle is travelling about twice as far horizontally as it is vertically. If you note the narration, near the end of the video they state the altitude and distance downrange. Distance is about twice the altitude.

As for the second, either the data displayed below is inaccurate (it was added later, I believe), the narrator is reading off a script that doesn't match to the correct info, or the audio is not accurately synched up to the video after the fact.

Mike

Sporally
2009-Jun-29, 06:59 PM
Yes, then it was the thing about downrange as expected.

Second question - it doesn't exactly look like something added with new homemade programs after YouTube was invented, but rather something from around the 70s. However, back then i guess there weren't many amateurs editing videos like this, but mostly professionals. I guess this is an exception.

Jens
2009-Jun-30, 02:47 AM
Second question - it doesn't exactly look like something added with new homemade programs after YouTube was invented, but rather something from around the 70s. However, back then i guess there weren't many amateurs editing videos like this, but mostly professionals. I guess this is an exception.

IIRC, lots of people had super-8 cameras back in the 1970s. Obviously not as many video cameras around as now, but still there were people who took amateur films.

Jeff Root
2009-Jun-30, 03:15 AM
It looks to me like something made recently on a PC. I see nothing to
indicate otherwise. Because I'm on dial-up, I only watched the first
half minute, but the time in the simulation values at the lower left are
behind the audio by a second or two from the start. That might be a
consequence of the huge reduction in the number of frames from the
original to the YouTube version.

-- Jeff, in Minneapolis

Sporally
2009-Jul-05, 09:08 PM
Two seconds, is that really everything.. Would say more though..