As of June 30, 2024, we leased 30 aircraft, airport facilities, office space, and other property and equipment under non-cancelable operating and finance leases. The leases generally require us to pay all taxes, maintenance, insurance, and other operating expenses. Operating leased expense is recognized as a rental expense on a straight-line basis over the lease term, net of lessor rebates and other incentives. Finance lease is capitalized and depreciated over the useful life of the asset.

Aggregate rental expense under all aircraft, equipment and facility leases totaled approximately $4.5 million and $3.6 million for the three months ended June 30, 2024 and June 30, 2023, respectively, and $17.1 million and $14.3 million for the nine months ended June 30, 2024 and June 30, 2023, respectively.


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024		2023
Operating lease costs	$	810	$	1,283	$	3,233	$	7,259
Variable and short-term lease costs		2,581		998	$	5,543	$	3,121
Interest expense on finance lease liabilities		746		230	$	3,291		734
Amortization expense of finance lease assets		365		1,046		5,001		3,138
Total lease costs	$	4,502	$	3,557	$	17,068	$	14,252

As of June 30, 2024, our operating leases have a remaining weighted average lease term of 6.5 years and our operating lease liabilities were measured using a weighted average discount rate of 6.0%.

Historically, Mesa Airlines, as lessee, entered into the RASPRO Lease Facility, with RASPRO as lessor, for 15 of our CRJ-900 aircraft classified as operating leases. The obligations under the RASPRO Lease Facility are guaranteed by us, and basic rent is paid quarterly on each aircraft. During December 2022, the Company entered into an agreement with RASPRO Trust, reducing the buyout pricing on all 15 aircraft at lease termination by a total of $25 million. Under the terms of the new agreement, the Company reclassified these leases as finance leases.