PHANTOM DRIVE SYSTEM 60% less fuel

[CAJIN]

The system utilizes a high torque low rpm diesel cummins engine set at a constant 1800 rpm under load with a fuel consumption rate of 3.1 gals per hour

It is capable of 5,000 rpm (plus) at the prop with the noise level under 40 dbl. 15 x 15 prop
10 gal hydraulic oil rez with heat exchanger keeps the heat under 180
12volt dc shift controller delivers both direction and speed functions
better

No drive shaft , no gears , no transmission , no smoke less weight,

[gonzo]

No drive shaft? What turns the propeller?
New diesels are fairly smokeless. Running at a constant RPM with variable loads doesn't change that. It is the same operating conditions as any generator.
Less weight? Hydraulics are notoriously heavy and inefficient. Post some real data.
No transmission? What transmits the power?

[CAJIN]

The EPA has just announced that UPS trucks have a simular drive system which has a 75% reduction in fuel consumption with better acceleration.

Many changes in the hydraulic industry in the past few years have resulted in better system design , less weight , increased out put , and the oil is bio degradable.
The prop is mounted directly to a variable displacment torque motor (no drive shaft , no U joints , no alignment problems) and the pump controls both direction and flow (no transmission) You might want to read up on this system, with in increased cost of fuel we all need to change our thinking .

[marshmat]

There are losses inherent in every transmission system imaginable. There is no possible way that replacing a gearbox with a hydraulic pump and motor will cause a 60-75% reduction in fuel use.
This topic has come up in other threads too. Hydraulics are inherently inefficient when compared to just about any other mode of torque transmittal. The notable exception is the car's torque convertor, which is quite inefficient in its natural state, but in today's cars can lock itself together to form a rigid coupling. The reason hydraulic pumps etc exist is their versatility- high torque/force rotary and linear actuators can be made to any specifications in any size for a wide range of applications. They are not used because of efficiency, but because of versatility.
I suspect the UPS truck system you mention is a variation of a pressure reservoir device develped a few years ago with the EPA's involvement. This device used a hydraulic motor/pump to force hydraulic fluid into an air-filled pressure tank while braking, storing the truck's kinetic energy as air pressure in the tank. When the accelerator was pressed, the pump/motor reversed direction and used that pressure to get the vehicle going again. The idea is similar to the regenerative brake of a Prius or Insight hybrid car.
Cajin- Please post links to some evidence of these devices.

[buckknekkid]

Hyundai

[gonzo]

Are you saying the motor is outside the hull, underwater directly bolted to the propeller? It would have a huge drag. If it is in the inside, then what connects it to the propeller? This is one of those "inventions" full of unproven claims. Post some real data.