|Sikorsky S-70C(M) Thunderhawk||Specifications||Service History||Images||Fleet Information|
Information on this page is kindly provided by Jason Tu.
The ROCN S-70C(M)-1 and S-70C(M)-2 helicopters (also referred to as Lot 1 and Lot 2, respectively) are configured with a single four-blade main rotor, a 20-degree canted tail rotor, a fully controllable stabilator, conventional fixed landing gear, emergency flotation, a rescue hoist, and weapons pylons for carrying and launching external stores. The S-70C(M)-1 is powered by two CT7-2D-1 turbine engines, while the S-70C(M)-2 is powered by two T700-GE-401C. In addition, both S-70C(M) models are equipped with a T-62-T40-2 auxiliary power unit to provide pneumatic power for starting the engines, operating the environmental control system, and electrical power for ground functional check and blade fold.
The flight control systems are hydraulically power-boosted mechanical control system.
Two hydraulic modules driven by transmission power the flight control system, and one
hydraulic module driven by electric motor provides emergency backup power to either
module and provides maintenance necessary on ground.
Another hydraulic module driven by transmission actuates sonar system and rescue hoist.
The automatic flight control system assists the pilot in maneuvering and heading the helicopter.
It is composed of the stability augmentation system, stabilator system, and digital automatic
flight control system that provide dynamic stability and maintain desired altitude, speed, and heading.
The AN/APS-143(V)3 search radar system is used to detect and track surface and air targets over a wide range of sea surface up to a range of 200 nautical miles and can be used for weather detection. The AN/AQS-18(V)3 sonar provides detecting, tracking, and classifying of underwater targets. It can be operated as either a dipping passive/active sonar or an acoustic processor for real-time display of data from passive/active sonobouy sensors, and also provides underwater voice communications and bathythermographic recordings. Other onboard systems include the AN/ASN-150 tactical navigation system, AN/ALR-606(V)-2 ESM gear, and one or two ARR-84 99-channel sonobuoy receivers.
There are three external stores/suspended bomb racks located at the helicopter left and right
external stores stations.
External stores may consist of torpedoes or auxiliary fuel tanks.
The Mk46 torpedo can be suspended from all bomb racks while
120-gallon droppable auxiliary fuel tanks may be suspended from the two inboard bomb racks only.
Although the primary mission the S-70C(M) is anti-submarine warfare, it can be easily converted for alternative missions of vertical replenishment, medical evacuation, and search and rescue. Aircrew consists of pilot, copilot, acoustic sensor operator, tactical sensor operator, and plane captain if necessary. It is designed to operate at sea aboard aircraft carriers, frigates, destroyers or cruisers with installation of RAST system. Also, the foldable main rotor blade, tail pylon, stabilator and extended weapon pylon are designed to fit narrow space on ships.
When the S-2T were transferred from ROCAF to ROCN in 1999, the Fleet Helicopter Group was redesignated the 2nd Aviation Group. The 701st HSL remained with this Group.
The 702nd HSL was commsioned on March 1, 2000, also under the auspice of the 2nd Aviation Group, in anticipation of the newly ordered S-70C(M)-2. Deliveries of S-70C(M)-2 began in April 2000. From March 1, 2001 to June 20, 2001, the 702nd HSL underwent operational training. It was declared operational on July 9, 2001.
During the first quarter of 2004, the S-70C operated by both the Air Force and Navy surpassed the 100,000 flight hour milestone. But unfortunately two S-70C(M) have been lost in accidents: