Considered to be the one of the most fundamental required documents in the aviation industry, the aviation medical certification is the pilot's ticket before he could fly solo. This applies to all kinds of pilots out there - sports pilots, recreational pilots, private pilots, military pilots or even student pilots - where it serves as legal evidence that the pilot is physically fit for any given flight. Even flight instructors are, at some circumstances that involve in-flight operations, required this as well.
The medical certification can be obtained from a physician of any local aviation authority where several tests are performed to figure out if the person concerned is capable for any flight operation. Some aviation groups also allow medical practitioners with specialization in aviation medicine to issue such certification.
In the United States, there are three types of aviation medicals: 1st class, 2nd class, and 3rd class which correspond to different types of general pilots namely airline transport pilot, commercial pilot and private pilot. Expiration dates also differ among three, with the 3rd class medical certificate having the longest duration before it even expires. US medical certificates are obtained from their regional flight surgeon's office or from the Federal Aviation Administration (FAA) unlike European ones which are obtained from the Joint Aviation Authorities, an associated body of European Civil Aviation Conference (ECAC).
In the UK, the UK Civil Aviation Authority serves as the specialist aviation regulator. Medical examination operation standards can be either for professional pilot or for private pilot license, both of which still require a medical certificate (from aeromedical examiners) that will testify that they are fit for flying. The types of aviation medicals depend on what type of pilot's license - private pilot, national private pilot, light aircraft pilot, and balloons and airships licenses.
The medical certification involves thorough and meticulous series of tests than you ever thought, as it is made to examine if the pilot is physically and mentally fit for any flight activity. Known as "flight physicals" these series of tests aim to check the pilot's periodic medical examinations. The usual team of medical personnel involved in this aviation medical examination includes a flight surgeon, a civilian physician, and medical doctor. Some of the disqualifying conditions that prevent any pilot from flying include psychosis, bipolar disorder, heart attack tendencies, substance abuse, implanted cardiac devices, motion sickness, mental and behavioral problems and many more.
The aviation medical certification is a prerequisite, much like a flight ticket, for pilots before they can legally consider flying solo. If you are a student pilot (or planning to become a solo pilot, such as an instructor) it's best to ensure if you have possible medical conditions that would hinder you from flying. This should be as early as possible as the certification is only required once you're about to go into the practical training. That way, you would know first beforehand if you're really medically fit for flight operations even before you start your training or school.