Abstract: The invention relates to oil and gas production and can be used for lifting liquid from wells by gas energy. The inventive flying valve comprises a tubular body, a detachable element in the form of a body of rotation and stoppers limiting the penetration of said element into the body. The detachable element or the tubular body or both of them are made of an oil-resistant material. The inventive method consists in periodically dropping said flying valve under the liquid level in the well to a lower bumper sub and in subsequently lifting the flying valve together with a liquid column which is disposed thereabove. The body and the detachable element are dropped separately, i.e. the detachable element of the flying valve is dropped before the body or vice versa.