Freezing rain? Teeth-chattering temperatures? Limited visibility? Coast Guard aircrews are still ready to fly.
“The weather here is worse than the two tours I did in Alaska … icy and bitter cold,” said Petty Officer 2nd Class Andrew “Sully” Sullivan, an aviation electronic technician (AET) who transferred to Air Station Cape Cod from Sitka, Alaska.
When the forecast calls for visible moisture, the risk of flying gets more challenging for the pilots and crew. Visible moisture can limit the pilots’ ability to fly as high as required in order to use the aircraft’s instruments.
According to Dewechter, the difficulty with flying in Cape Cod is that these conditions often occur at all altitudes. Air Station Cape Cod is a landlocked unit and none of the runways protrude to a body of water where there would be fewer obstacles in the flight path.
“To safely fly, we need to have a 300-400 foot ceiling and at least a one-mile visibility,” said Dewechter.
According to Lt. Ben Wolhaupter, another Jayhawk pilot at Air Station Cape Cod, a flight ceiling is when the sky is covered by at least 80 percent cloud coverage and is measured by the height of the layer of clouds above the surface of the earth or airport.
“For example, if one looks outside on a foggy day, the ground to the line of fog is called the ceiling,” said Wolhaupter.
According to Dewechter, Cape Cod’s cold weather often requires precise visual navigation under very low ceilings and low visibility to safely navigate from the airfield to the scene of a search and rescue case.
Depending on the weather, pilots can either rise above the moisture in the air or fly under it due to joint policies and procedures the Coast Guard has with the Federal Aviation Administration in order to fly in severe weather during search and rescue cases from that would normally ground commercial aircraft.
The Jayhawk is also the only search and rescue helicopter in the Coast Guard’s fleet able to deal with the icy weather from Maine to Northern New Jersey because it is equipped with both engine anti-ice and blade de-icing systems. AETs are responsible for making sure the systems are working properly before a flight.
Both anti-ice systems are spread out throughout the outside of the helicopter and around parts of the rotor blades, windshield and engines.
Sullivan said the anti-ice detector for the engines is mounted on the right engine and automatically provides information to the anti-icing system. The blade de-icing system is in the rotor head and tail rotor and it activates only if enough ice has accumulated.
Reed said wires flow down the rotor blades and a hot electronic pulse is sent out when there is ice buildup, melting it and keeping the blades in working order while in flight.
When the system is activated, the electronic pulse hits two blades at a time so as not to offset the helicopter’s weight.
“If all four blades are done at the same time, it could knock the helicopter out of the sky,” said Sullivan.
A Jayhawk helicopter crew is generally made up of two pilots, a flight mechanic and an aviation survival technician. The flight mechanic is an aviation maintenance technician or AET who is qualified on all the components of the helicopter necessary to keep it flying.
During a normal flight the side door remains closed, but during operations it is open so the flight mechanic can operate the hoist. In order to keep warm and battle the winds of the rotor blades, the flight mechanic wears multiple layers of clothing.
“We know we are going to be cold and wet,” said Reed, “Between the rotor blades pushing heavy winds down on us to the sea spray being kicked up because of the winds from the blades, it is inevitable.”
Flight mechanics can wear up to three layers of under garments and then their aircrew dry coverall. This suit has a rubber neck and wrist seals, keeping the aviator warm and the water out. It doesn’t replace having the helicopter’s heater running though.
“We are willing to sweat to make sure our aircrew stays warm,” said Dewechter.
The pilots do not have to worry about the cold weather coming in from the open door during operations; they are protected in the cockpit. However, in addition to flying in the frigid conditions, pilots have to make sure there is enough fuel to return home when the anti-ice system or heat is flowing through the aircraft.
“Under standard flying conditions the heat and anti-ice system cannot run at the same time,” said Dewechter.
The pilots and crew must consider weight and fuel consumption. The weight of individuals in the helicopter consumes a set number of fuel gallons. Running the heaters for the crew and survivors consumes additional fuel as well.
According to Dewechter, difficult decisions must be made to balance the need for the anti-ice system and the additional fuel burn of the auxiliary power unit on the helicopter to warm survivors pulled from the water.
But that’s not the only challenge where fuel is concerned.
“When icing conditions are present certain locations are no longer available for landing and close attention must be paid to fuel management and weather conditions in order to make sure we can land safely following a rescue,” said Dewechter.
When the aircrew is returning from an off-shore search and rescue case and freezing rain is pounding down on the helicopter, the crew knows the anti-icing systems will keep the ice to a minimum for a safe return home. The Coast Guard aircrews are trained and know what to do and how to perform their missions in the ever changing and always challenging New England weather.
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