Aerodynamics-Based Missile Interceptor







Runway-Based Routine Heavy Lift Access to Space







Space Power Grid Approach to Space Solar Power




Edu Kitchen: Thermoelectric Power Generation System


















































Learning To Innovate Across Disciplines:

Advanced Concept Exploration and Development


Aerodynamics-Based Missile Interceptor


The "Mutually Assured Destruction" (MAD) balance that existed during the Cold War years, has been upset. While there are more nuclear powers than existed in the Cold War years, the threat today is more from entities whose approach to rationality cannot be assumed. In other words, the assurance of retaliatory destruction cannot be assumed to be a sufficient deterrent to launching a surprise attack.

Ground-launched rocket-propelled weapons cannot offer a suitably reliable defense. They are also limited to a single launch each, and that launch has to occur instantly upon warning that ballistic missiles may be headed in the general direction of our nation. Thus the advantage is with an attacker: a number of multiple-warhead weapons can overwhelm any defense. This would offer a temptation to a suicidal entity. To counter this, our approach is to develop a defense system based on aerodynamics. It would consist of several aerial platforms (large aircraft) that would loiter efficiently at the edge of the troposphere, able to head towards the threat at transonic speed at the first warning. Supersonic UCAVs would be launched from these large platforms, and climb to high altitude and Mach 4, still able to abort, return and be recovered on runways for re-use. If the attack is real, the UCAVs will launch hypersonic missiles to do the intercept. In this scenario, enough force can be quickly brought to bear on the attacker, shifting the balance heavily in favor of the defender. Thus even a suicidal entity can see that an attack would have a very low, if not zero, probability of reaching any target, while the retaliation will be swift and assure annihiliation of the attacker and all its assets.

Can such a system be developed? Will the designs "close" at least from the aerodynamics point of view? After doing the conceptual design which brings in a number of different disciplines and issues, student teams then focused on the subsonic, transonic, supersonic and hypersonic aerodynamics of the different components to develop drag estimates at the needed lift values to perform the mission.

This was a class project in the AE3021 High Speed Aerodynamics course at GT in Fall 2011. Examples of work from a few teams of 2 students each, are presented by kind permission of the authors:


Runway-Based Routine Heavy Lift Access to Space


For Space Solar Power to have any hope of becoming a serious contender to replace terrestrial fossil electric generation, some 4000 Gigawatts of generation capacity must be installed in orbit. Even at the (unachieved today) specific power of 1 kWe per kg installed in orbit, this will take 4 million tons delivered to orbit at minimum. At 100,000 kg per launch, this will take 40,000 launches, or 1000 launches per year for 40 years. The launch cost must come down to around $400 per kilogram for SSP to be able to compete with other options for power generation. Only a routine, runway-based, reusable architecture that can be operated with minimal personnel, has any hope of achieving such low costs - but for the winner, there is a huge long-term market!

The studies presented are from the Integrative Project in AE3021 High Speed Aerodynamics in Spring 2013, as well the final examination in AE8803, High Speed Aerodynamics, also in Spring 2013. Presented by kind permission of the authors.