Brief overview of recent history and current CUSF projects

CUSF started in 2006 and typically has about 30 students. We used to fly a lot of High Altitude Balloons (HABs), now it's mainly rockets, although we do the occasional one for sponsors. The society has flown 3 major high powered rockets in the past, all part of the Martlet Series. Martlet 1 (M1) was a two stage solid rocket flown in Scotland, Martlet 2 was a solid rocket that flew in Mojave in 2015 - unfortunately a carbon fibre fin delaminated quite far into the flight so it didn't go as high as it should have. Martlet 3 which is the most relevant one so far flew in Nevada in 2017. Martlet 3 was really well built and was a two stage boosted dart rocket, but unfortunately the only off-the-shelf part they bought - the motor had a fault from the manufacture and blew itself up after 3km. Martlet 3 was meant to break the UK record. It did have really good avionics though, which survived a mid-flight explosion so there are possible plans to rebuild a similar system for Martlet 4(M4). Because the motor of M3 broke, the society decided to build completely in-house motors, and hence Pulsar was started.

Pulsar is the largest amateur engine ever fired in the UK, it's a 5kN hybrid rocket using nitrous oxide as its oxidiser and a HDPE fuel grain, with a burn time of about 20s. The Pulsar (and M3) projects were led by three people called Matt Escott, Matt Coates and Jack Brewster, with Joe Hunt (current president) also helping out. Those three guys spun-out a startup from CUSF after building Pulsar which builds small satellite orbital launch vehicles called Protolaunch. Pulsar had a test-stand built for it as well as a ton of plumbing which we are hoping to reuse for our liquid engine White Giant.

Martlet 4 (M4) is the rocket that Pulsar is meant to power. It's about 80% built, and was meant to launch 2 years ago but COVID prevented this, so we're going to finish it this summer and heave it ready to launch when we can. The main things not done for Martlet 4 are the manufacture of the fins (which have been designed) and the avionics. Martlet 4 is meant to go 20km (current UK record is 11km)

So, that brings us on to our current projects. So we ran some simulations last year and realised we could reach the well above the Karman Line to about 150km using a two stage rocket if the first stage was liquid and the second stage was solid. So, we're doing it and the rocket is called Griffin (changed from Martlet 5). The first stage is called Panthera and the second is called Aquila, although if you hear the name Condor then they mean the second stage (it was called this for ages so it's a habit sorry).

This year we are focusing on building the liquid engine and also building Aquila and testing it's hypersonic recovery system. The liquid engine is 10kN and uses Nitrous Oxide and IPA as the oxidiser and fuel. The main 10kN engine is called White Giant but first we are going to build a testing combustion chamber called White Dwarf which is 2kN and will allow us to get ignition and plumbing right.  A ton of work is being done for White Giant right now in sub-teams which are cooling, injectors, tank and test-stand.

- Kailen Patel - 11/4/2021- lightly edited 16/4/2021