Type II De-Ice N/A ?

[your_dreamguy]

Can someone explain why Type II de-icing fluid is not approved by some carriers? I heard Type II is corrosive...as one possible explanation.

 

[hyflyt560]

Back in 99 when I was going through Dash-8 type, an instructor stated that type II was not authorized on the Dash because of it's shearing properties. In other words, the type II would not shear at an appropriate speed in relation to Vr. Also, I believe de-ice/anti-ice products have to be reviewed yearly or biennielly...maybe someone can elaborate, and also help me with my spelling.

 

[cjdriver]

• Type I fluids are used for deicing or anti-icing, but provide very limited anti-icing protection.
• Type II fluids are designed to remain on the wings of an aircraft during ground operations, thereby providing anti-icing protection. This fluid should be used on aircraft with rotation speeds (Vr) above 100 knots, unless otherwise specified by the aircraft manufacturer.
• Type III fluids are designed for aircraft that have a shorter time to rotation and this should make it acceptable for some aircraft that have a Vr of less than 100 knots unless otherwise specified by the aircraft manufacturer.
• Type IV anti-icing fluids meet the same fluid specifications as the Type II fluids and have a significantly longer HOT.