Copyright © Thomas Fetter
I have used the PerfectFlite StratoLogger in all my rockets since its introduction. Before that, I had used its predecessor, the HiAlt45K (which lacked the data logging capability). I started using the HiAlt45K because of its high current output, which allowed me to use a wrapped nichrome wire without a pyrogen as an initiator for the deployment charge. The combination worked very reliably, so that is what I standardized on for deployment.
The Stratologger has the same high current output as the HiAlt45K, and added altitude data logging capability which I now use to analyze every flight.
Both the HiAlt45K and StratoLogger are very easy to set up and use, which reduces the risk of making an error when prepping a rocket for flight.
This is the current model of the StratoLogger. I have flown two of these successfully in my most recent rocket, SpeedRunner 75.
This is the older model of the StratoLogger that I have flown many times with no failures.
Here is the basic configuration of the altimeter ebay that I use in dual-deployment rocket configurations where the drogue deploys reward, and the main deploys forward. These pictures are of the 3 inch diameter by 8 inch long ebay from SpeedRunner 75.
I like to make the ebay completely removable for easy access. The ebay is made from coupler diameter tubing that is held in place by bolts that go thourgh the rocket body and into t-nuts or pem-nuts that are attached to a mounting plate and glued to the inside of the ebay.
If there is room, as in this case, I always use two altimeters for redundancy.
I use floating battery connectors, rather than fixed battery holders with buildt in contacts. That way, if the battery moves a little under acceleration, it the connector goes with the battery, and the battery doesn't unplug itself. I also mount the batteries through a cutout in the mounting sled and hold them in place with two thin aluminum sheetmetal covers. Being "in" the sled, the batteries are very secure, but are still easy to remove. Also, in smaller diameter rockets, centering the battery makes good use of the small available space.
I use u-bolts as opposed to eye-bolts to reduce the chance that the bolt unscrews itself as the rocket twists during recovery. Small stainless steel u-bolts are available from McMaster-Carr.
Ebay configuration for a 38mm minimum diameter dual beployment rocket. The battery mounts in a cutout in the ebay sles, and the ebay tube serves to hold the battery in place.
PerfectFlite Data Capture Software
The PerfectFlite DataCap Software is used to program the StratoLoggger and to download and display the stored data.
Photos courtesy of PerfectFlite