April 17, 2012:
The U.S. Coast Guard has ordered two more HC-144 ("Ocean Sentry") MPA (Maritime Patrol Aircraft). The coast guard already has 15 of these aircraft, and plans to eventually have a fleet of 36. The first one entered service six years ago and carried out its first search and rescue mission four years ago. Last year HC-144s flew 10,250 hours on patrol missions. Some were over land, when there was a natural disaster that needed air recon quickly.
The Ocean Sentry is actually a militarized CN-235, which is a cheaper ($19 million each) alternative to the P-3 that the U.S. Navy uses for high seas recon. The CN-235 suits the coastal patrol needs of the coast guard.
The CN-235 is a civilian twin engine, 15 ton aircraft with a max payload of six tons. With about three tons of sensors and other equipment, a typical load for an MPA, the CN-235 can stay in the air for up to eleven hours per sortie. Most missions are about ten hours. Cruising speed is about 435 kilometers an hour. The CN-235 is equipped with a thermal imager and electronic monitoring equipment, in addition to the sea search radar.