API Engineering LLC 
Design and System Engineering Services 

Undersea Programs

Project Title




SMTD Torpedo Propulsion

Firm Fixed Price Consulting and Design & Development

Martin Marietta Naval Systems and Argo-Tech Corporation

Adaptation of 12.75 inch diameter Otto fueled MK46 piston engine propulsion system to 6.25 inch diameter torpedo countermeasure.

  • systems engineering and detail design and development services
  • in-water demonstration vehicle met all propulsion demo objectives
  • vehicle level conceptual design and propulsion systems engineering  
  • detail design of the hull primary structure,
  • technical management of a high performance fin actuator
  • engineering development testing
  • successful design and development of the first ever deployable control fin for  tube launched undersea application  
  • highest bending moment hull joint ever done.

MMD Countermeasure Propulsion and Control

Time and Materials


Bendix Oceanics

Proposal support for a submarine tube launched mobile acoustic countermeasure using battery electric propulsion.

  • vehicle level and propulsion systems engineering and proposal prep
  • systems engineering included vehicle hydrodynamics for drag, powering, 6 DOF vehicle dynamics modeling, autopilot design, tube launcher interface management, propulsion battery/motor trades.
  • Navy cancelled program before an award decision

MK50 Torpedo Second Source

Time and Materials




Proposal support for second source production of the MK50 Torpedo, a lithium and sulphur hexafluoride heat source, Rankine cycle turbine propulsion system.

  • full range of proposal support for a large scope 6 month proposal  
  • led to selection of the TRW/Westinghouse team as the second source supplier for the MK50 torpedo.
  • Services included consulting in top level strategy and approaches  
  • conducted training to the TRW staff in MK50 propulsion technology
  • provided technology assessment and advice

Closed Cycle Stored Heat Engine

API and Ettem Internal Development

(Ongoing program)

US Navy (pending)

Internal development of an undersea propulsion system based on stored heat energy and closed Brayton cycle technology.

  • Design/development of a prototype heat storage system
  • Fabrication of engineering model closed Brayton cycle engine
  • implementation of high performance regenerator technology

LELFAS/UUV Wick Stirling Power System Heater Head

Firm Fixed Price


AlliedSignal for ARL Penn State

Long duration Stirling cycle power system using lithium and sulphur hexafluoride heat system.

  • Design/fab of heater head (pistons, cylinders, flow passages, & structure)
  • structural & thermal analyses of high temperature (1800F) liquid metal environment

Other undersea projects have included the following.

            An Advanced Heavyweight SCEPS propulsion system study - TRW
A Hydrogen Oxygen Combustor design - AlliedSignal