PML Co-Pilot 2.0 Question

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Well-Known Member
Feb 13, 2009
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This weekend at Red Glare was my first venture into dual-deployment, using a scratch built that incorporates PML's CPR system with a Co-Pilot altimeter. I had two successful flights on an AT J350W and J420R respectively.

The problem I'm having is reading the 'Last Peak Velocity' entry of the flight log. In both instances, I get 1 short beep, 1 long beep, 4 short beeps, 1 long beep, then the ending chirp. The velocities for the 2 motors should have been statistically different. I used the altimeter in 'basic' configuration with the main deployed at 500'. No default settings were modified. Other items in the flight log appear correct.

I would greatly appreciate if anyone who's used this altimeter could explain the results I'm getting, since they don't seem to match what the instructions say.

Are you saying the velocity reading was the same for both motors?
You only mention 1 reading.
I haven't had identical results for 2 different motors yet, in 16 flights.

I have many flights on mine and was getting wildly vary on the peak v. also .
Some of the results made no sense, such as a K flight where common sense would predict around .8 mach and the read out was 2.5 mach, after translating the ft/sec to mach, which is about 1160 feet per sec. [can't remember exact off hand]
A call to Jim Amos of Missleworks resulted in the following info:

This feature is just there for fun and is highly inaccurate. There was extra space available to write the program but not enough to do it justice. The way it samples the data during the flight is such that it is just a ballpark figure and sometimes not even that. To do justice to this feature on the altimeter would kick up the price point. And for a 75.00 altimeter it already does a ton of stuff. That's the gist of the matter anyhow.

I had the same concerns you did and he put them to rest.
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Thanks for the quick response.

The velocity readings for both flights were identical.

My main concern was the interleaving of short and long beeps. If I treat them equally, I read the response as 1141 fps. Not bad for a quantum tube rocket! :eek: I think the actual velocity was somewhere around 830 fps based on Rocksim and my actual altitude readings.

I guess I'll have to shell out the cash for a recording altimeter to satisfy my curiosity for data.