We have significant long-term lease and debt financing obligations, and we may incur additional obligations as we expand our aircraft fleet and operations. As of December 31, 2023, all of our aircraft are wholly or majority-owned by third parties and leased to us.
On October 5, 2022, we entered into a Pre-Delivery Payment Agreement ("PDP Agreement") with a Shearwater Global Capital entity for the financing of PDP Agreement payments on four Gulfstream G280s under four separate purchase agreements executed in March 2022 ("G280 Purchase Agreements"). The PDP Agreement is secured by all of our rights in the G280 Purchase Agreements, all of the reserves under the PDP Agreement, each of the Aircraft, and all present or future additions, attachments, or accessories thereto and replacements thereof, all engines and avionics, all tools, manuals, service records, software, and similar information and materials related to each G280, all payments, amounts, refunds, rebates, and all other amounts of any kind whatsoever relating to any or all of the Purchase Agreements and/or any or all of the aircraft, and the products, proceeds, rents, and profits therefrom or thereof. The PDP Agreement provides for a Twelve and Half Percent (12.5%) interest rate on all PDP Agreement promissory notes ("PDP Notes") issued by the lender for payments made under the PDP Agreement, for an aggregate principal balance of up to $40.5 million. As of December 31, 2023, there is a balance of $28.5 million in PDP Notes, with $2.0 million in letters of credit with Chase Bank that are secured with $2.1 million in restricted cash (interest-bearing). Additionally, the Company issued a promissory note to Dennis Liotta in the original principal amount of $1.0 million with a maturity date of March 31, 2024, and an interest rate of Ten Percent (10%).
The ability to timely pay our existing or future contractual obligations, including our long-term lease obligations and required payments under the PDP Notes, will depend on the results of our operations, cash flow, liquidity, and ability to secure additional financing, which will in turn depend on, among other things, the success of our current business strategy, U.S. and global economic and political conditions, the availability and cost of financing, and other factors that may be beyond our control. If our liquidity is materially diminished, our cash flow available to fund our working capital requirements, debt service obligations, capital expenditures, and strategic initiatives may be materially and adversely affected, or we may not be able to realize the benefits of, or otherwise maintain, certain relationships with our business partners. We cannot be assured that our operations will generate sufficient cash flow to make any required payments, or that we will be able to obtain financing to make expenditures in pursuit of our strategic initiatives. The amount of our contractual obligations and timing of required payments could have a material adverse effect on our business, results of operations, and financial condition.