Lars Pepermans

T-Minus Engineering

The Stratos III and IV missions of Delft Aerospace Rocket Engineering (DARE) are sounding rockets that aimed to reach altitudes between 60-100 km altitude. In order to recover the payload sections of the Stratos III and IV rockets, a two-stage recovery system was designed, containing a drogue parachute to stabilise and decelerate the vehicle. The d...

Retrieval systems are a vital part of sounding rocket missions. Even if the mission is completely successful, the failure in the retrieval subsystem can lead to the payload not being found back and thus a mission failure. This paper describes several retrieval strategies ranging from simple systems to highly complicated highly reliable systems. Sev...

The primary objective of the Supersonic Parachute Experiment Aboard REXUS (SPEAR) was to fly and collect in-flight data of a Hemisflo ribbon parachute at supersonic conditions. In November 2022, the SPEAR vehicle was successfully launched on top of the REXUS 28 sounding rocket from Esrange in Sweden. Shortly after the REXUS 28 apogee at 96 km, the...

Parachutes have been a key feature in space exploration and engineering. Not only have parachutes been used for Mars landings or other planetary exploration missions, but also on reusable launch vehicles. These include the Rocketlab Electron rocket and the first Falcon 9 launches. However, in Europe, there are significant knowledge gaps regarding p...

Parachute testing is available in numerous shapes and forms, with each method being suitable for different applications. This paper aims to provide an overview of the various testing methods and to discuss the advantages and disadvantages they bring. The paper first identifies the relevant parameters for parachute tests and matches these to the var...

The Large Envelope Advanced Parachute System (LEAPS) is developed as a means of recovering the flight data to prove that a student-built sounding rocket, Stratos IV, has reached space. Several design modifications are outlined in this work. The drogue parachute is deployed using a hot gas deployment system to save mass and volume and to increase re...

T-Minus Engineering currently offers two calibres of in-house developed solid rocket motors. The motors are classified as the 116 mm and the 215 mm motor, each with their own sub-types. These motors can be used for a variety of scientific research. This research includes atmospheric research, micro-gravity research, and free-flying research. This p...

Parachute testing has always been an integral part of the verification and validation of planetary landers and other missions requiring a parachute decelerator. It is desirable for these tests to be performed in conditions as close to the intended flight as possible. Amongst the various testing options, flight testing offers a significant advantage...

The paper discusses the lessons learnt during the SPEAR mission that takes part in the 12th cycle of the Rocket EXperiment for University Students (REXUS) sounding rocket programme. The mission originated after Delft Aerospace Rocket Engineering (DARE) designed a supersonic-capable drogue parachute and was unable to test it supersonically on the ex...

Various parachute-type decelerators can be considered in the design of a sounding rocket recovery system. During the development of various flagship missions of Delft Aerospace Rocket Engineering (DARE), the Parachute Research Group of DARE has developed several methods and criteria to select the right parachutes for a given mission. This paper pre...

Parachute testing is available in numerous shapes and forms, while each of them is suitable for different applications. This paper aims to provide an overview of the various testing methods and discuss the advantages and disadvantages they bring. The paper first identifies the relevant parameters for parachute tests and matches these to the various...

Delft Aerospace Rocket Engineering, DARE, is a society with the goal of reaching space with a student-built sounding rocket. The latest iteration, Stratos IV, is designed with this goal in mind. To prove Stratos IV reached space, the flight data needs to be safely retrieved. The Parachute Research Group (PRG) of DARE developed the Large Envelope Ad...

The Supersonic Parachute Experiment Aboard REXUS (SPEAR) is an experiment flown on the REXUS28 sounding rocket as part of the REXUS/BEXUS program. The REXUS cycle lasts 1.5 years, giving the mission a strict timeline. The SPEAR mission aims to test the behaviour of the in-house developed Hemisflo ribbon drogue parachute at supersonic conditions. To...

In order to increase the reliability of parachute systems, Delft Aerospace Rocket Engineering (DARE) required a test vehicle that could reach dynamic pressures comparable to a Stratos-type mission. This project became known as the DARE Parachute Investigation Project or PIP. The initial PIP launcher flies to an apogee of about 1000 meters where the...

The Large Envelope Advanced Parachute System (LEAPS) of Delft Aerospace Rocket Engineering is a flexible parachute recovery system developed for several flagship missions. These flagship missions have masses varying from 10 to 40 kg and apogees varying from 10 to 120 km. The flagship missions considered for LEAPS are: project Aether, Stratos III, a...

Reusable launch vehicles hold the promise of substantially reducing the cost of access to space. To date, many different approaches towards realising a reusable rocket exist or are proposed. This work focuses on the use of an optimisation method for conceptual design of non-winged reusable upper stages, thereby allowing it to take into account diff...

Besides recovering a rocket for just the flight data, one can opt to recover the entire rocket, including the tank and engine. This can be done for public relation reasons, but also with full rocket reusability in mind. This article describes three concepts using parachutes to recover a sounding rocket in its entirety. As a reference design, a Stra...

Stratos III is a rocketry project led by students from Delft University of Technology. The goal of this project is to reclaim the European student altitude record for a sounding rocket, which is currently set at 32.3 km. The flight data of this rocket has to be retrieved to definitively prove the altitude at apogee. As not all data is sent down and...

In the summer of 2016 a group of students from Delft Aerospace Rocket Engineering (DARE) started a project to reclaim the European altitude record for amateur rocketry currently set at 32.3 km by HyEnD. This project was named Stratos III as a follow-up on Stratos II+. To recover the flight data, video footage, payload and valuable hardware, the nos...