In February 2020, we refinanced two secured term loans that were originally due later in 2020, with two new term loans. One term loan is for 126 months in the amount of $82.0 million at a fixed interest rate of 3.27% with a final payment of $12.5 million due in July 2030 (the “First 2020 Term Loan”). The other term loan is for 130 months in the amount of $82.0 million at a fixed interest rate of 3.28% with a final payment of $12.5 million due in November 2030 (the “Second 2020 Term Loan”). The First and Second 2020 Term Loans are each secured by a mortgage against a 777-200LRF aircraft and subject to usual and customary fees, covenants and events of default, with principal and interest payable quarterly.

In April 2020, we borrowed $14.6 million at a fixed interest rate of 1.15% under an unsecured five-year term loan due in April 2025 for GEnx engine performance upgrade kits and overhauls (the “Third 2020 Term Loan”). The Third 2020 Term Loan is subject to customary fees, covenants and events of default, with principal and interest payable quarterly.

See Note 3 for a discussion of the Promissory Note we issued to the U.S. Treasury during the three months ended June 30, 2020.

In May 2017, we issued $289.0 million aggregate principal amount of 1.875% convertible senior notes that mature on June 1, 2024 (the “2017 Convertible Notes”) in an underwritten public offering. In June 2015, we issued $224.5 million aggregate principal amount of 2.25% convertible senior notes that mature on June 1, 2022 (the “2015 Convertible Notes”) in an underwritten public offering. The 2017 Convertible Notes and the 2015 Convertible Notes (collectively, the “Convertible Notes”) are senior unsecured obligations and accrue interest payable semiannually on June 1 and December 1 of each year. The Convertible Notes are due on their respective maturity dates, unless earlier converted or repurchased pursuant to their respective terms.

	2017 Convertible Notes			2015 Convertible Notes
Remaining life in months		47			23
Liability component:
Gross proceeds	$	289,000		$	224,500
Less: debt discount, net of amortization		(42,795	)		(16,934	)
Less: debt issuance cost, net of amortization		(3,318	)		(1,569	)
Net carrying amount	$	242,887		$	205,997

Equity component ⁽¹⁾	$	70,140		$	52,903

The following table presents the amount of interest expense recognized related to the Convertible Notes:

	For the Three Months Ended				For the Six Months Ended
	June 30, 2020		June 30, 2019		June 30, 2020		June 30, 2019
Contractual interest coupon	$	2,618	$	2,618	$	5,235	$	5,235
Amortization of debt discount		4,457		4,186		8,845		8,308
Amortization of debt issuance costs		391		375		777		747
Total interest expense recognized	$	7,466	$	7,179	$	14,857	$	14,290

We have a $200.0 million secured revolving credit facility that matures in December 2022 (the “Revolver”). As of June 30, 2020, there was $175.0 million outstanding and we had $16.2 million of unused availability, based on the collateral borrowing base. In July 2020, our unused availability, based on the collateral borrowing base, increased to $25.0 million. [In August 2020, we repaid $175.0 million and had $200.0 million of unused availability.]