Apogee Recording Altimeter

I'm interested in buying a new altimeter and noticed thge Apogee unit records for up to 5 minutes. ANyone have used one out there ? Dave Ketchledge

RocketEngineer wrote:
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     No, but I have used the Alt15K/WD logging altimeter (no deployment)works great.
See also http://www.perfectflite.com /
Yes it's the same altimeter
BW

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Hi Dave, Apogee is just a reseller of the PerfectFlite 15K altimeter.
BTW, they work great

RocketEngineer wrote:
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Dave, I launched one in my LOC Weasel clone on H73, Saturday ... the altimeter read 3115'. my rocksim says 3135'. I'd say that's close enough! now I have a calibrated rocksim and I am going to for exactly a mile.

Is 5345' close enough to a mile? I can tell you how I did it very simply.
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nitram578 wrote:
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tell us!

Cliff Sojourner wrote:
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Why??

The best recording altimeters, judging from the data, are from Adept. The data are filtered well enough that one can derive velocity and acceleration from them - also thrust and Cd curves with a little extra work in vertical flights. That's a lot better than the data from other altimeters I've seen. Not actually familiar with the PerfectFlite.
Regards -Larry Curcio
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Larry Curcio wrote:
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if you really want velocity, accelleration, jerk, buy an altimeter with an accellerometer.
my PerfectFlites work great but they are barometric only.

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That was a little uncivil, don't you think?

I wrote:
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http://en.wikipedia.org/wiki/Jerk

Steve Humphrey wrote:
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I think someone owes me a new keyboard.
You learn something new everyday.
-Aaron

snipped-for-privacy@comcast.net says...
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'twas well done, indeed.
Bravo!

I wrote:
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oh my goodness!!! I sure didn't mean it like that! I was not being uncivil, the wikipedia entry for jerk is what I meant - 2nd derivative of velocity. it made sense when I typed it late at night.
very sorry nad I hope everyone gets a laugh out of this.

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Who's a 'nad' ??? ;-)
RDH8

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Yeah, first he calls someone a jerk, now this!
Who does he think he is? ;-)

I assume, by Jerk, you mean the third derivative of altitude :-)
Adept altimeter data are good enough to be double differentiated by Savitsky-Golay filters to give acceleration curves. They have the opposite problem that accelerometers have. They measure only in the vertical dimension To the extent that the trajectory is vertical, the acceleration is righteous.
Had thought I'd made a breakthrough with this double differentiation, but evidently the Adept software does it too.
BTW, I have traditionally been so far in the accelerometer camp that, as far as I know, Tommy dislikes me. We have no connection whatever.
-Larry (Deriving the jerk could be stretching it) C.
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