Clear Ice
Joined: May 2000
Posts: 3,204
Likes: 2
From: Seattle
How much "Clear Ice" (per the subject line)? NONE!!!
The only "ice" allowed is the FROST caused by supercooled fuel in the wing tanks condensing and freezing moisture on the lower surface. That's US rules, though; CAA/JAA/others may have different rules...
The only "ice" allowed is the FROST caused by supercooled fuel in the wing tanks condensing and freezing moisture on the lower surface. That's US rules, though; CAA/JAA/others may have different rules...
Joined: Jun 2002
Posts: 3
Likes: 5
From: Wor Yerm
I think that unless your aircraft or company manuals specifically state a value, the answer is none! It's up to them to supply a value. Ours allows a trace, not exceeding 3mm, on the underside of the wings in the area of the fuel tanks.
Joined: May 2000
Posts: 3,204
Likes: 2
From: Seattle
FAR 121.629(b):
(b) No person may take off an aircraft when frost, ice, or snow is adhering
to the wings, control surfaces, propellers, engine inlets, or other critical
surfaces of the aircraft or when the takeoff would not be in compliance with
paragraph (c) of this section. Takeoffs with frost under the wing in the area
of the fuel tanks may be authorized by the Administrator.
As Piltdown said, authorization as in the last sentence would be in your FHB, FOM, or similar document. Note that the document would have to be one approved by the FAA, not just a company policy document.
(b) No person may take off an aircraft when frost, ice, or snow is adhering
to the wings, control surfaces, propellers, engine inlets, or other critical
surfaces of the aircraft or when the takeoff would not be in compliance with
paragraph (c) of this section. Takeoffs with frost under the wing in the area
of the fuel tanks may be authorized by the Administrator.
As Piltdown said, authorization as in the last sentence would be in your FHB, FOM, or similar document. Note that the document would have to be one approved by the FAA, not just a company policy document.
