New Hopper2 Missile Reveals Future of Missiles

Stoke Space conducted a successful 15-second vertical take-off test of its reusable Hopper VTVL missile, capable of returning and landing after performing the functions of the second stage of a launch vehicle. This test, known as the Hopper2 test, took place at the training ground in Moshes Lake, Washington on September 17, 2023.

Over the past decades, there has been a significant shift in the concept of orbital missiles. Previously considered disposable, they have now evolved into advanced reusable systems. This advancement not only reduces the cost of launches but also expands their capabilities.

The Hopper2 prototype reached a height of 9 meters (30 feet) within 15 seconds during the test. Although seemingly modest, the goal was to demonstrate several advanced systems for future second stage missiles.

One of these systems is the missile engine, which utilizes hydrogen and oxygen. Images published by Stoke Space reveal an airplane-like design for the engine, featuring a conical cross-section. During take-off, the change in atmospheric pressure allows for automatic adjustment of the bell’s cross section to increase efficiency. Additionally, individual engine thrust adjustments can be made to control the rocket’s position in space—an advantage of the engine ring.

The test also included the first trial of a regenerative cooled heat shield, essential for a rocket’s return to the atmosphere from orbit and subsequent landing. Traditionally, heat shields have utilized ceramic tiles or an ablation phenolic plastic shield. In regenerative cooling, fuel from the rocket circulates behind the shield, providing heat removal before it is supplied to the engines.

Once operational, Stoke Space claims that the rocket will be 100% reusable, with a restart period of 24 hours.

/Reports, release notes, official announcements.