The February spacewalk at the International Space Station marked the first ISS excursion that left the station temporarily unoccupied. But for Jim Wiehoff of Boeing, it was noteworthy for another reason: He found himself in a tough position.

When power to a panel in the ISS Zvezda Service Module was turned off in preparation for this spacewalk, the power to the Portable Computer System in the module also was cut. That marked a violation of a flight rule requiring two PCSs to monitor ISS systems. Upon hearing of this, Wiehoff, an Embedded Software Engineer for the ISS program in Houston, started thinking about what could happen if things went wrong on the ISS without the redundancy. That led Wiehoff to do what he felt was the right thing: express his concerns.

Wiehoff called his counterpart at the Mission Operations Directorate, the NASA wing responsible for operating the ISS. Wiehoff explained the flight-rule violation and declared his concern for proceeding with the spacewalk.

Wiehoff called his direct supervisor, who supported him. "I felt he was making the correct decision, and I told him that," said David Canfield, a senior manager in the Hardware Software Integration organization for the ISS program in Houston.

"I took it up the management chain to make sure they were all aware of the situation, and they were 100 percent behind him," Canfield added, noting that Wiehoff's integrity, honesty and experience make him "very much a leader."

Wiehoff then took the next step in raising his concerns: talking to those in the Mission Evaluation Room. Some people wondered if he was making too big a deal of the issue. Yet Wiehoff held firm.

The MER team elevated the risk to the top-level mission management team. They evaluated the risk and made the decision to proceed based upon all parties being made aware of the situation and the fact that all consoles and the crew could react with contingency plans if something were to go wrong. The spacewalk progressed normally, although it was cut short by a space suit malfunction. The astronauts were never in any danger.

Wiehoff's actions provoked discussions regarding processes for decision making and handling of flight rules. As a result of his actions, combined with the new environment after the Space Shuttle Columbia accident, some changes are being considered to improve the process for ensuring that inputs from all affected parties are considered. The flight rules for required equipment for a spacewalk also have been rewritten to clarify when it is appropriate to proceed.

Since then, Wiehoff said a number of people have commended him for doing the right thing.

"I feel really good about it," Wiehoff said about his actions that day.

"We had a good, positive outcome with the new procedures that might not have happened if I didn't speak up."

-Junu Kim