Property, Plant, and Equipment, net

6 Months Ended

Mar. 31, 2023

Property, Plant and Equipment [Abstract]

The components of property, plant, and equipment, net consisted of the following:


(in thousands)	March 31, 2023		September 30, 2022
Land	$	—	$	995
Building	—		8,805
Equipment	47,284		42,330
Furniture and fixtures	1,571		1,394
Computer hardware and software	3,379		3,378
Leasehold improvements	7,772		7,180
Construction in progress	5,264		9,886
Property, plant, and equipment, gross	$	65,270	$	73,968
Accumulated depreciation	(38,945)		(36,101)
Property, plant, and equipment, net	$	26,325	$	37,867

Depreciation expense totaled $1.6 million and $3.0 million during the three and six months ended March 31, 2023, respectively and $1.0 million and $2.0 million during the three and six months ended March 31, 2022, respectively. During the six months ended March 31, 2023, the Company consummated the sale of the real property interests in the Tinley Park Facility to 8400 W 185TH STREET INVESTORS, LLC, resulting in net proceeds of approximately $10.3 million and a gain on sale of assets of

$1.2 million. During the three and six months ended March 31, 2022, we sold certain equipment and incurred a gain on sale of assets of $0.8 million and $0.6 million, respectively.

During the quarter ended September 30, 2022, there was a triggering event of negative cash flows and operating losses at the FOG asset group level within the Inertial Navigation product line of the A&D segment that indicated the carrying amounts of our long-lived assets may not be recoverable. In accordance with ASC 360, with regard to our long-lived assets, we performed an undiscounted cash flow analysis and concluded that the carrying value of the asset group was not recoverable. Accordingly, we then performed an analysis to estimate the fair value of the other long-lived assets and recognized an impairment charge within operating expenses of $3.0 million against the FOG property, plant, and equipment by the amount by which the carrying value of the asset group's other long-lived assets exceeded their estimated fair value for the fiscal year ended September 30, 2022. Key assumptions utilized in the determination of fair value include expected future cash flows and working capital requirements. While we believe the expectations and assumptions about the future are reasonable, they are inherently uncertain.

Geographical Concentrations

Long-lived assets consist of land, building, property, plant, and equipment. As of March 31, 2023 and September 30, 2022, 94.7% and 95.4%, respectively, of our long-lived assets were located in the United States.