This thread is a long time coming for me! Earlier in June 2018, I started planning my L3 project, and decided I wanted to build a large rocket. I decided to use the Madcow 8" DX3 as a starting point and modify it by adding nearly 40" in length, and using CNCed interlocking fin pockets and centering rings from Upscale CNC. After taking a step back, and adding up the costs of all of the components, plus a 98mm case and a M1939, I realized that this was going to be an expensive build, and also a large one that would not be easy for me to transport any time soon. So, I took a step back and looked at my options. On the grounds of economy, I already had a LOC 5.5" Sandhawk that I had just started to work on, and had just finished fiberglassing the airframes on. I immediately stopped all work on that project, and wrote a new proposal for an L3 attempt using the Sandhawk. This would benefit me in several ways. First, the total cost of the project would be about half of the DX3, once I bought a 75mm case and a motor. Second, I already had the kit, and third, the wife would be extremely happy I wasn't breaking the bank on one rocket! After submitting my proposal packet to a local L3CC member, I had a false start and a bunch of what I will call miscommunications between the two of us. One of the issues was that I had already started the build, which is a no go under NAR L3 rules. After it was pointed out to me by Steve Shannon that that was perfectly ok under TRA cert rules, I decided to switch up and do the cert under my TRA membership. After some more communications with my L3CC member, who is also a TAP, and asking Steve to be my second TAP, I have been given the green light to proceed. The Rocket: As mentioned, I am using the LOC 5.5" Sandhawk as the basis for the build. I decided to do away with the plastic nosecone, and picked up a Madcow fiberglass nosecone. I also will be using a SC Precision thrust plate with an Aeropack retainer. The basic components, still with the plastic nosecone Thrust plate and retainer As I mentioned above, I had previously fiberglassed the airframe. I used Soler Composites heavy sleeve for the fiberglass. Airframe section in work. Of course, I had to do the obligatory dry fit photo of the project after I fiberglassed the tubes... So, what's next? I need to start assembly of the motor mount and fin can. I will most likely be fabricating plywood fin pockets for fin mounting, and also need to decide if I want to bevel the fins or not. Then there is also the avionics bay that will need to be built. I have already decided to use my tried and true combination of a MissileWorks RRC3 and a StratologgerCF for my altimeters, as well as the MissileWorks RTx tracker. For recovery, I have a custom harness from Teddy at OneBadHawk on hand, and I plan on using Rocketman chutes for recovery. The cert flight is currently planned to use a M1550R, which should see an altitude of right around 8,000ft. One of the requests from my primary TAP is that I fly this on a 75mm L first, and I was already planning on such. So its first flight will be on a L1390G, hopefully at the Fire in the Sky launch on Memorial Day weekend.