Status Report

NASA Presolicitation Notice: Station-Shuttle Power Transfer System (SSPTS)

By SpaceRef Editor
October 26, 2003
Filed under , , ,

General Information

  • Document Type: Presolicitation Notice
  • Solicitation Number: NNJ-BG1-C06-4-001P
  • Posted Date: Oct 23, 2003
  • Original Response Date: Dec 22, 2003
  • Original Archive Date: Oct 23, 2004
  • Current Archive Date:
  • Classification Code: A — Research & Development

Contracting Office Address

NASA/Lyndon B. Johnson Space Center, Houston Texas, 77058-3696, Mail Code: BG


NASA/JSC has a requirement for the Station-Shuttle Power Transfer System (SSPTS). The SSPTS project will provide the capability to transfer International Space Station (ISS) power to the Space Shuttle Orbiter while the Shuttle Orbiter is docked to the ISS in order to extend the mission duration.

The scope of this effort includes system integration of the power transfer function between ISS and SSP: development, qualification, manufacturing, test and installation of a power conversion Line Replacement Unit (LRU) on all three shuttle Orbiters; associated Shuttle Orbiter modifications, and associated ISS modifications required to support this functionality. The SSPTS Project extends Orbiter-ISS docked time by transferring ISS 120VDC power to Orbiter, where it is converted to Orbiter-standard 28VDC. The SSPTS Project deliverables consist of kits installed on both ISS and Shuttle Orbiter vehicles such as Extravehicular Activity (EVA) installed wiring harnesses on ISS, wiring modifications and associated control functionality on all three Orbiters, and new 120V to 28V Orbiter Power Converter Unit LRU design. NASA/JSC intends to purchase the items from Boeing Space and Communications Group.

The SSPTS requires intimate knowledge of both ISS and Shuttle Electrical Power Systems to assure the proposed power transfer design is safe and protects against fault propagation into either power system. Boeing is the Technical systems manager for both the Space Shuttle power system (through the SFOC contract) and the ISS power system (through the ISS Vehicle sustaining contract), and as such has unique knowledge of not only the infividual power systems, but of the integrated system needs. Additionally, Boeing has developed prototype power conversion systems meeting the integrated system needs using internal R&D funding. This project also requires tight integration with the Auxiliary Power Conversion Unit (APCU), previously built and integrated to the Shuttle systems by the Boeing Company. Additionally, the short delivery requirement for this system eliminates other potential sources due to the extensive learning curve required to become familiar with Shuttle and Station power system requirements and safety protections.

The combination of factors puts the Boeing Company in position as the only responsible source for this integrated system. The Government does not intend to acquire a commercial item using FAR Part 12. See Note 26. See note 22. Interested organizations may submit their capabilities and qualifications to perform the effort in writing to the identified point of contact not later than 4:30 p.m. local time on November 15, 2003.

Such capabilities/qualifications will be evaluated solely for the purpose of determining whether or not to conduct this procurement on a competitive basis. A determination by the Government not to compete this proposed effort on a full and open competition basis, based upon responses to this notice, is solely within the discretion of the government.

All responsible sources may submit an offer which shall be considered by the agency. An Ombudsman has been appointed. See NASA Specific Note “B”. Any referenced notes may be viewed at the following URLs linked below.

Original Point of Contact

Thomas N. Neeley, Contracting Officer, Phone (281) 244-7644, Fax (281) 244-8041, Email – Laura G. Pepper, Contracting Officer, Phone (281) 244-7261, Fax (281) 244-7563, Email

Email your questions to Thomas N. Neeley at

SpaceRef staff editor.