Congress has until the end of this week to fund the federal government or agree on a continuing resolution to keep the government funded. Absent either of those actions, the government will shut down starting Oct. 1.
A CR would be "bad," but a shutdown would be "horrible," said William A. LaPlante, undersecretary of defense for acquisition and sustainment.
LaPlante spoke at the Center for Strategic and International Studies' International Security Program.
"If the government shuts down, testing [of systems] will stop and acceptance by the government of equipment when it is finished and ready to be accepted [could] stop," he said.
For example, in 2013, during the government shutdown, factory workers were sent home. Production lines on things like munitions and the F-35 Lightning II stealth multirole combat aircraft stopped.
Next week, the Defense Department has some testing to do for an item it has earmarked for Ukraine, he said.
"Unless we can get some type of a waiver, it's not going to happen," he said.
Also, people are not going to be able to travel to work on acquisition and sustainment projects, "so, it's just extremely disruptive," he said.
"The message it sends to the government workforce is, we're sending people home, our engineers, our acquisition professionals, our sustainers our contracting officers, we're just sending them home and saying you're not essential," LaPlante said.
The other option is for Congress to pass a continuing resolution. CRs maintain the previously appropriated year's level of funding for federal programs for a specified period of time.
In the case of a CR, any increases in production are not going to happen without a special waiver, he said.
In past CRs, this negatively impacted production of Guided Multiple Launch Rocket Systems and Patriot surface-to-air missile systems, he said.
Both of those systems have been sent to Ukraine.
LaPlante noted that China, which is the department's pacing challenge, never has continuing resolutions or government shutdowns.