14 CFR § 205.7 - Cancellation, withdrawal, modification, expiration, or replacement of insurance coverage.
(a) Each policy of aircraft accident liability insurance and plan for self insurance shall specify that it shall remain in force, and may not be replaced, canceled, withdrawn, or in any way modified to reduce the minimum standards set forth in this part, or to change the extent of coverage, by the insurer or the carrier, nor expire by its own terms, in regard to coverage for the carrier in its common carrier operations in air transportation, until 10 days after written notice by the insurer (in the event of replacement, by the retiring insurer), or by the insurer's representative, or by the carrier, describing the change, to the Department at the addresses specified in § 205.4(c), which 10-day notice period shall start to run from the date such notice is actually received at the Department. For purposes of this part, a policy will not be considered to have expired if the same insurer renews its coverage without reduction in the extent of coverage or amounts of coverage, and without a break in coverage, whether or not a new policy is issued, and notice to the Department is not required in that event. If the coverage being changed is by type or class of aircraft or by specific aircraft, endorsements adding or deleting specific aircraft or types or classes of aircraft, for which prior notice would be required by this paragraph, shall be filed in accordance with § 205.4(b), and prior notice of the change need not be given under this paragraph.
(b) The requirements of this section shall not apply if the policy contains a lesser time period for cancellation in a war risk exclusion. If the war risk exclusion is activated by the insurer, the insurer or its representative shall immediately notify the Department.