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ASV
21st Jul 2002, 12:21
HELLO THERE , I'M LOOKING FOR ANY INFORMATION & PHOTO FOR A HELICOPTER WITH ICE IN IT , PLEASE I NEED IT A.S.A.P.... MANY THANK'S:rolleyes:

ASV
21st Jul 2002, 12:49
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Labpilot
21st Jul 2002, 13:30
Here's a link to Rotorwash International's gallery

http://www.rotorwashinternational.com/gallery/Civilian-Helicopters

A little ice on a Super Puma.

ASV
21st Jul 2002, 19:29
Refresh :confused:

Flap 5
25th Jul 2002, 14:04
Flying Characteristics (Sikorsky S61N):

Collective comes up under your armpit. Nose comes up. Speed drops off. Helicopter goes down. Nasty smell in cockpit.

The last is a biological rather than mechanical symptom. Fortunately over the North Sea the temperature is always above zero just over the sea (or so I am told) and the ice shook itself free.

sycamore
25th Jul 2002, 19:27
There are so many variables with regard to icing on helo`s that you have to be extremely careful if you enter an icing environment. Rotor icing- depends a lot on the blade section.rotor speed ,and power setting ,but in general,ice will form from about 10-70%span,kinetic heating will stop it forming outboard;the ice formation will/may accrete back to the max. thickness area,and is 10% thicker than the blade thickness,and can project forwards by the same amount in an inverted U shape.It will also stick on blade tape.It may/may not shed .If it does it will be uneven,will increase vibn,may go down intakes/tail rotors etc.The major danger ,however, is that you will get a major Tq. increase for a constant colltve.setting.IF the tq. rises/falls periodically you may be OK,if it doesn`t and you lose an engine you now have a load of ice/lots of Drag,and you will not be able to keep RRPM.The only way of keeping RRPM is to roll into a spiral descent,and stick with it all the way down,keeping a bit of "g"on which may help to shed some ice!....Then there is the ice on the stabiliser,not de-iced,which may cause pitch oscillations.ice over cooling ducts,etc..it in no way compares with icing in a fixed wing a/c and this is only in stratiform type cloud.It also relates to Seaking/Wessex/Wasp type a/c.To say nothing about engine intake icing,and compressor damage.Never fly into rain-ice conditions with a cold a/c as the ice will form in a smooth formation on the blades with a slow Tq build-up,but you cannot shed the ice as it is forming on the rear section of the blades.Any one who flies a modern helo with deicing/anti-icing kit may disagree,but I would suggest you may be Russian and fly a big Mil.:p

ASV
26th Jul 2002, 04:26
:)

Thomas coupling
28th Jul 2002, 23:18
depends what flavour it is and whether there is icing on the top AND sides (my favourite):D

400 Hertz
29th Jul 2002, 07:26
Water, below freezing point (0 degrees C) can still remain in a liquid form until it hits an object. This object creates a shock which allows the water to solidify. Hence ice on blades and fuselage = out of balance and extra weight.

A lot of investigation into the formation of ice has taken place. The result is that modern aircraft have ice sensors which uses optical technology to measure the impacted ice build up on a bar and indicate to the pilot the liquid water content based on timed readings.

Heated rotor blades are used on some aircraft, these use masses of electrical power and are not normally that reliable due to the harse enivironment.