The MH-53J's mission is to perform low-level, long-range, undetected penetration into denied areas, day or night, in adverse weather, for infiltration, exfiltration and resupply of special operations forces. The MH-53J Pave Low III heavy-lift helicopter is the largest and most powerful helicopter in the Air Force inventory, and the most technologically advanced helicopter in the world. Its terrain-following, terrain-avoidance radar and forward-looking infrared sensor, along with a projected map display, enable the crew to follow terrain contours and avoid obstacles, making low-level penetration possible. The helicopter is equipped with armor plating, and a combination of three 7.62mm miniguns or .50 caliber machine guns. It can transport 38 troops or 14 litters and has an external cargo hook with a 20,000-pound capacity. The MH-53J has twin turbo-shaft engines; self-lubricating, all-metal main and tail rotors; and a large horizontal stabilizer on the tail rotor pylon's right side.