The BOLT-1B hypersonic test vehicle of the U.S. Air Force successfully completed a flight in Norway on September 2.
The BOLT-1B took off from the Andøya Space Sub-Orbital Launch Center in Norway, reaching a maximum altitude of 254 km, before descending into the sea about 185 km offshore as planned, as reported by Interesting Engineering on September 6. The vehicle accomplished all its test objectives, and the project team gathered a wealth of data for analysis in the coming months. The BOLT-1B flew over the Norwegian Sea at a speed of Mach 7.2 (7.2 times the speed of sound, approximately 8,890 km/h), providing critical data on the physical properties of airflow at hypersonic speeds.
The BOLT-1B hypersonic vehicle is tested to study the boundary layer transition phenomenon. (Photo: Johns Hopkins University).
The project is coordinated by the U.S. Air Force Office of Scientific Research and executed by the Johns Hopkins University Applied Physics Laboratory (APL), the Aerospace Systems Directorate of the U.S. Air Force Research Laboratory (AFRL/RQ), and the German Aerospace Center (DLR).
The project aims to investigate the boundary layer transition phenomenon (the airflow around the surface of the hypersonic vehicle), which increases drag and aerodynamic heating of hypersonic vehicles. The BOLT-1B is equipped with numerous instruments to conduct over 400 measurements, with installation locations determined through extensive research to better understand the physical properties of the boundary layer transition relative to the vehicle’s shape.
“The data we collected from the flight tests is crucial for improving the design methodologies of future hypersonic vehicles, helping to reduce model uncertainty and optimize their performance,” said Brad Wheaton, a scientist at APL and the principal investigator for the project.
| Hypersonic vehicles are those that travel faster than five times the speed of sound, or Mach 5. Airflow is always a key factor in the flight of these vehicles. According to Johns Hopkins University, accurately determining whether the air is moving in a laminar flow (smooth straight motion) or has transitioned to turbulent flow (swirling with a heat transfer capability eight times greater) is vital for identifying the materials needed when designing hypersonic rockets and aircraft. |
