SIOUX CITY -- With necessary testing of the USS Sioux City delayed, the ship's commissioning has been pushed back to this fall.

No date has been set, but the event still will take place at the U.S. Naval Academy in Annapolis, Maryland.

The rescheduling was the result of weather, mechanical issues and the aggressive milestones the Navy sets for bringing new ships into service, retired Navy Real Adm. Frank Thorp said.

"As they upgrade, they continue to find challenges. It takes longer than expected. The Navy, when it comes to bringing a ship to life, is overoptimistic," said Thorp, chairman of the USS Sioux City Commissioning Committee. Thorp announced the new commissioning schedule while in Sioux City to boost fundraising for the commissioning events.

Thorp said sea trials near a Wisconsin shipyard on Lake Michigan planned for last fall were not done before the lake froze over. Those trials now are tentatively scheduled to begin in May, following the lake's anticipated thaw in April. Mechanical problems identified during trials will then be repaired before Navy personnel take the ship to sea for acceptance trials. Once those trials are completed and the Navy accepts the ship, it will sail through the Great Lakes to Norfolk, Virginia, for final preparations before arriving at Annapolis for commissioning.

The delays are necessary to make sure the USS Sioux City, which was christened and launched at the shipyard in January 2016, is ready for service at the time it's commissioned, Thorp said.

"In the end, the Navy will not commission this ship until it's ready to fight and win," he said.

In the meantime, Thorp continues to work with local Commissioning Committee members to meet the $800,000 fundraising goal for the ship's commissioning festivities. Thorp said that more than $250,000 has been raised, most of it from sources in and near Sioux City. Eldon Roth, co-founder of Dakota Dunes-based Beef Products. Inc., contributed $100,000 of that amount.

Other major sources of donations will come from the Annapolis area and from defense contractors, Thorp said, but the commitment -- financial and emotional -- the city and its residents have shown to the ship is unlike any other relationship between a ship and its namesake city that he has seen in 28 years in the Navy.

Future crew members who have visited Sioux City have reported feeling like rock stars because of the many offers people have made to buy them coffee or dinner and the appreciative ovations they've received during public appearances, Thorp said.

"I have been absolutely overwhelmed by the appreciation and the desire for that relationship from the city," Thorp said. "The engagement has been phenomenal."

The USS Sioux City is the 11th in the class of littoral combat ships, which are designed to operate in shallower water close to shorelines. The ship will have a 98-person crew and be used for maritime security throughout the world.

Once commissioned, the USS Sioux City will sail to its home base in Mayport, Florida, before it's deployed. Thorp said the ship's future crew is currently training in Mayport and has yet to move onto the ship.