View all text of Subjgrp 185 [§ 27.951 - § 27.977]
§ 27.969 - Fuel tank expansion space.
Each fuel tank or each group of fuel tanks with interconnected vent systems must have an expansion space of not less than 2 percent of the tank capacity. It must be impossible to fill the fuel tank expansion space inadvertently with the rotorcraft in the normal ground attitude.