l need to find out if there is a loan on a particular aircraft, and if so, the principal amount.

Thomas,
Like Kristen, l do not know either. l suggest that you check with your banker. There is probably some agency that acts as a clearing house for these debts.

Regards,
Dan

ever think of calling the leinholder. jeez. l like these easy ones.

Check the record of the aircraft from the registering authority. They have all the details on record. If the aircraft in under lien, they will have this in the register. Perhaps u may not be able to ascertain the actual amount of the loan, but u will have the right to know about it if u wish to purchase the aircraft. If u do sign a 'Memorandum of Understanding' (MoA) with the owners for purchase of the aircraft, u will then be eligible to know all the details. Further, in the MoA, u can state that u r buying the aircraft 'free from all loans, encumbrances, liens & any or all third party claims'.
This will ensure that at the time of deletion of the aircraft from the register & transfer to ur name, the regulatory authority will ensure adherence to ur MoA. In the meantime, u would have asked the sellers of any loans, & they should have been obliged to inform you.