Final answer:
The FAA Form 337, known as the Major Repair and Alteration form, is used to document the installation of a cabin-installed long range fuel tank in U.S registered aircraft. This form is critical for maintaining records of major alterations that affect an aircraft's airworthiness and for informing the FAA of such changes.
Step-by-step explanation:
The FAA Form 337, also known as the Major Repair and Alteration form, is used to record the installation of a cabin-installed long range fuel tank in a U.S registered aircraft. This form is submitted to the Federal Aviation Administration to keep track of any major changes or repairs to the aircraft's structure, powerplant, systems, or components that may affect its airworthiness and operational characteristics.
When installing additional equipment like a long-range fuel tank, which significantly alters the aircraft's weight, balance, structural integrity, or performance, the responsible maintenance technician or engineer must complete the FAA Form 337. Following the installation, the signed form is then kept with the aircraft's permanent maintenance records and a copy is submitted to the FAA.