Current Status and Controversy of Cannae Drive and EmDrive Propulsion Systems

As of my last update in August 2023, both Cannae Drive and EmDrive propulsion systems are considered controversial and largely unproven concepts in the field of propulsion technology. In this article, we will explore the concepts, current status, and ongoing research surrounding these technologies, examining the claims made by their proponents and the skepticism from the scientific community.

The Cannae Drive

Concept: The Cannae Drive, proposed by inventor Guido Fetta, claims to generate thrust without the need for propellant by using oscillating electromagnetic fields. The theory suggests that by manipulating the paths of charged particles, the drive can produce a net thrust.

Status: While there has been limited experimental validation, mainstream scientists remain skeptical about its feasibility. The lack of a clear mechanism that aligns with known physics, particularly the conservation of momentum, is a significant issue. The absence of a viable theoretical framework that explains the observed effects means that further experimental proof is needed.

The EmDrive

Concept: The EmDrive, or electromagnetic drive, is a proposed spacecraft propulsion system that supposedly generates thrust by bouncing microwaves within a closed conical chamber. The idea is that the microwave radiation, when directed in a specific way, can produce a net thrust.

Status: Initial tests, including those conducted by NASA's Eagleworks lab, reported small thrust measurements. These results, however, have met with significant skepticism from the scientific community. Many argue that the observed thrust could be attributed to experimental errors or other conventional explanations such as thermal effects.

General Consensus and Skepticism

Both technologies are often discussed in the context of advanced propulsion research but have not achieved the level of acceptance or reproducibility required for practical application. The general consensus is that further rigorous experimentation and validation are necessary to determine their true potential.

Tom Nickels' Analysis:

Tom Nickels, who has extensively analyzed the EmDrive, notes that it is not a hoax but rather a grandiose claim that suggests a lack of seriousness. The device has reported a thrust of 100 micro-Newtons, which is far too low to support a mission to Alpha Centauri. The EmDrive is believed to violate the conservation of momentum and the laws of physics as they are currently understood. If it worked, it would necessitate a fundamental reorganization of established physics, which requires an extraordinary level of proof.

Moreover, the EmDrive can be theoretically used to construct a working Perpetual Motion Machine, which is a significant reason for skepticism. As Tom Nickels explains:

The EmDrive as a Perpetual Motion Machine

An EmDrive of mass M is attached to one end of a rigid, massless beam of length R. The other end of the beam is attached to a frictionless axle. The moment of inertia of the beam and drive is I MR^2. Electrical power of Pi watts is supplied to the EmDrive through slip-rings. A dynamo is connected to the axle, and the output can be used to supply the EmDrive and surplus can be directed externally.

The EmDrive produces thrust T and, therefore, a torque RT. The torque produces an angular acceleration alpha RT/I. The angular velocity omega will increase linearly: omega alpha * time. It will be necessary to extract energy or apply some braking force to prevent the device from self-destruction.

As the system accelerates, the power output is Po omega * Torque omega * RT. At some point, Po exceeds Pi. The excess power can be sold to the power grid.

As a concrete example, set Pi to 50 W, R 5 m, and Thrust T 1 N. Then the break-even point is omega 10 rad/s. If the machine is allowed to accelerate to 20 rad/s, the power output will be 100 W. 50 W can be used to supply the EmDrive. The remaining 50 W is available for sale to the electric utility.

This is a very small demonstration unit. Larger units will generate megawatts of power, which can be sold to the electric utility, providing funds for the mission to Alpha Centauri.

A unit of this type, properly miniaturized, could be carried in the Alpha Centauri expedition vessel, supplying power to the propulsion EmDrives. The possibilities are truly awesome; however, these claims need to be rigorously tested and verified before they can be considered reliable.

For the most current developments beyond August 2023, I recommend checking the latest scientific publications or news articles in aerospace engineering.