FlyingNanook From United States of America, joined Jan 2004, 830 posts, RR: 10 Posted (11 years 4 months 3 days 20 hours ago) and read 4435 times:
Yesterday, I flew out of SFO on my way home to FAI on AS. It was raining while we were boarding the plane (MD-80). I was watching the action on the ramp, when one ramper pulled a ladder up to the wing. He climbed up the ladder and probed the wing with a long wooden stick with a rubber tip. I thought he might be checking for ice, but it was well above freezing.
JetMechMD80 From United States of America, joined Jul 2004, 380 posts, RR: 6
Reply 3, posted (11 years 4 months 3 days 20 hours ago) and read 4301 times:
Sounds like he was checking for ice. I doesn't have to be anywhere near freezing on the ground to have ice on the wings, especially on an aircraft that just flew in. And the MD-80 is notorious for a phenomena called "super cooling" of the wings. You didn't say if he was on top of the wing, or under it. If he was on top, he had to be checking for ice. The sumps, and the fuel sticks are on the bottom.
OPNLguy From , joined Dec 1969, posts, RR:
Reply 4, posted (11 years 4 months 3 days 20 hours ago) and read 4283 times:
After the SAS MD80 crash off-airport in Sweden a few years back, MCD installed these little plastic "tufts" on the top of the wing. From what I recall reading, it you can move the tuft with a stick/pole, you're good to go, if not, it's because there's ice on the wing and you need to take care of it before departure...
Anyone current on the MD80 family, feel free to chime in; the above is just what I recall reading...
Citjet From United States of America, joined Nov 2004, 97 posts, RR: 0
Reply 7, posted (11 years 4 months 3 days 19 hours ago) and read 4225 times:
Ive had to do the inspection that is being described. The process of doing the inspection for ice on the wing is just that. You use a long stick with a rubber tip. The reason for moving the stick around on top of the wing is to see if the ruff section of the upper wing (its like a non-slip surface) is actually smooth or ruff. If it is ruff, the flight is good to go. If the patch is smooth, then that means ice exists. The most important reason for doing this is to prevent any ice from coming loose during take-off and fouling one or both of the engines during climb out. Ice can form on any surface of an aircrafts wing when the tanks contain super cooled fuel. That ice will still form when it is 70 degrees outside. Trust me. Ive made snow balls from the frost that forms on the bottom of the wing before.
Ive worked for the airlines for seven years and now Buisness Aviation for six. Any questions, Id be happy to entertain. I certainly dont know everything though.
L-188 From United States of America, joined Jul 1999, 30404 posts, RR: 57
Reply 11, posted (11 years 4 months 2 days 23 hours ago) and read 3446 times:
I thought he might be checking for ice, but it was well above freezing.
You guessed the right answer.
Even though it was above freezing it doesn't mean the fuel in the wing is, particularly if the aircraft has been on a prior flight. These cold fuel can chill the surfaces of the wing, drawing moisture out of the air causing condensation and then frost to form. This frost formation has been blamed for at least one MD-80 loss, when it broke off and FOD'ed the engines.
When I was working for AS in 94, they had a policy that if an MD-80 sat on the ground fewer then a certain period of time (I forget how many hours) it had to be de-iced....regardless of the time of the year.
OBAMA-WORST PRESIDENT EVER....Even SKOORB would be better.
FlyingNanook From United States of America, joined Jan 2004, 830 posts, RR: 10
Reply 12, posted (11 years 4 months 2 days 22 hours ago) and read 3381 times:
Thanks all, I was just curious because I have never seen this done before, even though I live in Alaska. The plane was on the ground for about 30 minutes, but there was no de-icing, so that policy probably no longer exists.
Wbmech From , joined Dec 1969, posts, RR:
Reply 13, posted (11 years 4 months 2 days 21 hours ago) and read 3312 times:
De-icing was not needed. That is why the check is performed. You are supposed to feel a difference between the rough no-slip paint and smooth paint on the wing to determine if there is ice buildup in the wing. If it is all smooth or all rough, that means that there is ice buildup and the wings need de-icing. There is an AD out to perform these checks before each flight. It is linked in one of many posts in A-net.