747hogg From , joined Dec 1969, posts, RR: Posted (6 years 7 months 3 weeks 5 days 2 hours ago) and read 2739 times:
I have always wondered about the streaks and lines of the grey and black stuff on the wings of big jets, even after coming out of one hell of a rain storm, they are still there. Is this lubracation being blown onto the wings from the gear and motor sections of the flaps? I have flown some jets that were totally clean, but most look really dirty from the pax point of view. How hard is that stuff to get off?
Charlienorth From United States of America, joined Jun 2006, 1077 posts, RR: 5 Reply 1, posted (6 years 7 months 3 weeks 5 days 2 hours ago) and read 2733 times:
After an aircraft exits a check where "grease cards"(work orders)were accomplished the excess grease comes out of the serviced areas,whether flight controls or landing gear,it gets quite difficult to clean off,in non technical terms the best way to describe it is "gooey"
HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58 Reply 2, posted (6 years 7 months 3 weeks 4 days 8 hours ago) and read 2634 times:
Lubrication is carried out thru Fittings & Applied by hand.During mvmt of the Surface lubricated,excess Grease is thrown around.This is cleaned at Layover checks.
regds
MEL
RedFlyer From United States of America, joined Feb 2005, 4181 posts, RR: 30 Reply 3, posted (6 years 7 months 3 weeks 3 days 12 hours ago) and read 2556 times:
Quoting Charlienorth (Reply 1): After an aircraft exits a check where "grease cards"(work orders)were accomplished the excess grease comes out of the serviced areas,whether flight controls or landing gear,it gets quite difficult to clean off,in non technical terms the best way to describe it is "gooey"
Quoting HAWK21M (Reply 2): Lubrication is carried out thru Fittings & Applied by hand.During mvmt of the Surface lubricated,excess Grease is thrown around.This is cleaned at Layover checks.
regds
MEL
Just out of curiosity: if it's only lubricant (grease, gooey, etc.), why is it only on the wings and never on other surfaces? I would imagine that other moving parts also get the lubricants but you never see the streaks anywhere else except on the wings.
See this pic of a WN aircraft on the tarmac. Only the wings have the streaks. I suspect its actually hydraulic fluid.
Greasespot From Canada, joined Apr 2004, 3050 posts, RR: 22 Reply 4, posted (6 years 7 months 3 weeks 3 days 11 hours ago) and read 2552 times:
The grey and black streaks is leaking skydrol. It is actually in the paint now and that is why it does not wash away.
If you look where the streaks are you will find a flap/slat/ or spoiler actuator in most cases.
gs
Sometimes all you can do is look them in the eye and ask " how much did your mom drink when she was pregnant with you?"
Buzz From United States of America, joined Nov 1999, 697 posts, RR: 24 Reply 5, posted (6 years 7 months 3 weeks 3 days 9 hours ago) and read 2534 times:
Hi 747Hogg, Buzz here. About 20 years ago we had a crew of aircraft polishers who would work the 727 while we did a B check on that airplane.
They could get most of the mess (skydrol, oil grime) with stoddard solvent (PSD60, Varsol) on a mop. After the solvent scrub had dried, they would apply wax to the airplane.
Charlienorth From United States of America, joined Jun 2006, 1077 posts, RR: 5 Reply 7, posted (6 years 7 months 3 weeks 3 days 1 hour ago) and read 2489 times:
Kaddyuk From Wallis and Futuna, joined Nov 2001, 4125 posts, RR: 28 Reply 8, posted (6 years 7 months 3 weeks 3 days 1 hour ago) and read 2486 times:
Quoting Charlienorth (Reply 7): ,it does seep through panels and you ere often reminded of the good time of winter when you open these panels,the odor of maple syrup..
It does dry to them and look like peeling paint... Although not a stain, if you dont know what you're looking at, it can look like a skydrol leak...
Some of the dirt streaks you see on aircraft are exactly that, dirt. Such as from rivet heads (a good indication of corrosion). From panels (the B747 Pylons come to mind) of black rubber sealant between them. Leaking fuel tanks, skydrol stains etc etc...
Also, the reason dirt doesnt get blown away is due to the viscosity of the air and the boundary layer, Grease will wipe away easily, the dirt can be removed with a foaming cleaner (Such as Amberclens).
Whoever said "laughter is the best medicine" never had Gonorrhea
Fr8Mech From United States of America, joined Sep 2005, 4260 posts, RR: 12 Reply 9, posted (6 years 7 months 3 weeks 3 days 1 hour ago) and read 2481 times:
Quoting Greasespot (Reply 4): If you look where the streaks are you will find a flap/slat/ or spoiler actuator in most cases
Which is also where many of the grease fittings are.
As you may have guessed from the posts, the stains can be a mixture of products. Grease is the most common. The dirt that adheres to the grease really makes it show up, though the color of the grease, (brown, black or green) shows up nicely against a wing and/or control surface.
Hydraulic leaks also cause streaking. All actuators give up some minuscule amount of fluid during actuation. This fluid may get caught in the airstream and dirty things up somewhat.
Greasespot From Canada, joined Apr 2004, 3050 posts, RR: 22 Reply 10, posted (6 years 7 months 3 weeks 3 days ago) and read 2471 times:
Quoting Fr8Mech (Reply 9): Which is also where many of the grease fittings are.
Yes that is true. But It does not take long to recognize the difference between a grease trail and a skydrol trail. The black long streaks tend to be skydrol as no matter how much scrubbing you cannot make it go away. The skydrol softens the paint and gets embedded. However a grease trail you can wash off.
I will bet a lick of the wing on that B737 that the long black streak on the port wing near the tip is skydrol.
GS
Sometimes all you can do is look them in the eye and ask " how much did your mom drink when she was pregnant with you?"
Lemurs From United States of America, joined Mar 2005, 1439 posts, RR: 4 Reply 11, posted (6 years 7 months 3 weeks 3 days ago) and read 2467 times:
Quoting Greasespot (Reply 10): I will bet a lick of the wing on that B737 that the long black streak on the port wing near the tip is skydrol.
One of my long-standing rules in life, that I never have had the chance to use before now, is: "Never make a bet about grease stains with a man who name suggests intimacy with grease." Thank you for letting me use the rule to it's fullest potential.
There are 10 kinds of people in the world; those who understand binary, and those that don't.
Nonfirm From United States of America, joined Sep 2005, 434 posts, RR: 0 Reply 12, posted (6 years 7 months 3 weeks 2 days 22 hours ago) and read 2452 times:
Quoting RedFlyer (Reply 3): Just out of curiosity: if it's only lubricant (grease, gooey, etc.), why is it only on the wings and never on other surfaces? I would imagine that other moving parts also get the lubricants but you never see the streaks anywhere else except on the wings.
See this pic of a WN aircraft on the tarmac. Only the wings have the streaks. I suspect its actually hydraulic fluid.
There is also streaks around the belly of the a/c and sometimes you can get grease spot on the aft lower fuselage from excess grease that has come off the from the wing and gear lubes as well.
BOE773 From , joined Dec 1969, posts, RR: Reply 13, posted (6 years 7 months 3 weeks 2 days 20 hours ago) and read 2426 times:
A dirty aircraft is an eyesore and very difficult to clean especially if the paint has oxodized since the grease/skydrol 'soaks' into the paint. During walk-around I find it interesting to see how the airflow acts over surfaces by the dirty tail-off patterns from the grime especially under the fuselage belly behind the wheel wells. Grime streaks do tell a story.
Starlionblue From Hong Kong, joined Feb 2004, 15871 posts, RR: 66 Reply 16, posted (6 years 7 months 3 weeks 2 days 18 hours ago) and read 2401 times:
Quoting Lemurs (Reply 11): Quoting Greasespot (Reply 10):
I will bet a lick of the wing on that B737 that the long black streak on the port wing near the tip is skydrol.
One of my long-standing rules in life, that I never have had the chance to use before now, is: "Never make a bet about grease stains with a man who name suggests intimacy with grease." Thank you for letting me use the rule to it's fullest potential.
Nice try but as I learned a long time a go, Greasespot is actually Ms. Spot.
"There are no stupid questions, but there are a lot of inquisitive idiots." - from Citadel by John Ringo
BOE773 From , joined Dec 1969, posts, RR: Reply 17, posted (6 years 7 months 3 weeks 2 days 17 hours ago) and read 2394 times:
Quoting Greasespot (Reply 15): Nah a bleeding actuators is normal..There is actually a MM limit as to how fast it drips as to when it needs to be pulled..
GS
What's the In-Service DPM for a 737 slat actuator, GS ?
That WN actuator piston has stroked too many times across it's 'O' ring
Lemurs From United States of America, joined Mar 2005, 1439 posts, RR: 4 Reply 18, posted (6 years 7 months 3 weeks 2 days 17 hours ago) and read 2394 times:
Okay, I know you have no reason to believe me, but I swear as I was typing that out, I thought to myself: "Watch...Greasespot is going to be a woman." I even went back and changed it, and then changed it back figuring the odds were low, and that playing the pronoun game would ruin the oomph of the joke. I never assume gender on the Internet, and whenever I do, in either direction, I am wrong. (This comes from having a typically female name as a guy...I am on the wrong end of gender assumptions WAY too often.) I need to stick with my instincts here, and listen when my brain tells me I am going to regret something.
(Notice how nowhere in my mental evaluation did "Click on the name and find out" get considered...I am not always running at 100% here folks.)
My apoligies, Ms. Greasespot!
There are 10 kinds of people in the world; those who understand binary, and those that don't.
BAe146QT From United Kingdom, joined Sep 2006, 996 posts, RR: 0 Reply 19, posted (6 years 7 months 3 weeks 2 days 13 hours ago) and read 2367 times:
Modern political correctness practices are obviously well-ingrained with me, since the most obvious alternative phrasing I can think of is;
"Never make a bet about grease stains with a person whose name suggests intimacy with grease."
Incidentally, I like it. I'm going to add it to the list:
Never eat at a place called "Ma's".
Never play poker with a man called "Doc".
Never buy version 1.0 of anything.
Never sleep with someone who has more troubles than you do.
Kaddyuk From Wallis and Futuna, joined Nov 2001, 4125 posts, RR: 28 Reply 24, posted (6 years 7 months 3 weeks 1 day 21 hours ago) and read 2249 times:
Quoting HAWK21M (Reply 22): The drops are counted as they drop & not after they hit the surface
Leaks come in buckets... not drips...
Whoever said "laughter is the best medicine" never had Gonorrhea
25 Nonfirm: Here are some leak limits for the 737-400. PART---- NORMAL---- MAX Tube Connections---- None---- None Static Seals---- 1 per 10 min---- 10 drops per m
27 Greasespot: Good someone else posted it. We only have the MM on tape format here and I hate using them. GS
28 BOE773: Can't be that tough to teach an oler dawg new tricks, Greasespot, eh?
29 HAWK21M: If it leaked buckets its AOG We have luckily upgraded to CD Roms holding data in PDF format & MBF access. regds MEL
30 JetMech: The dirty brown streak left by tea and coffee poured down the galley drains and the tenacious ability of this waste to adhere in a sticky mess to the
31 MD11Engineer: Just taste it! Deicing fluid tastes sweet, like sugar water, skydrol burns on the tongue. Many airlines today consider washing aircraft, especially w
32 JetMech: Quoting MD11Engineer (Reply 31): Remeber the dirt behind the outflow valves when they still permitted smoking on board? Or how the insulation and the
33 MD11Engineer: I remember having had to dismantle and clean PSU's which were removed during a D-check together with another apprentice during my apprenticeship days
34 HAWK21M: What was their Justification for that. Yeah the Nicotine stains on the vents were prominent. regds MEL
35 JetMech: I don't know if the airline in question actually permitted smoking, but that didn't stop the Captain from lighting up. I think that the country this
36 Lemurs: That's what makes antifreeze the suicide poison of choice for people in the know who want to make sure it gets done right. You can mix it into a cock
38 Greasespot: Thanks Yeah If i never taste Skydrol again that will not be a bad thing........I guess i could just rub it in my eye in the future... I was fortunate
39 HAWK21M: How about Freighters is smoking permitted on them.Out here its not. regds MEL
40 BAe146QT: And that's the same reason why any glycol product should be locked away from children and should never be decanted into a container other than that w
42 HAWK21M: Anyone aware of any Officially permitted smoking in any Carriers. regds MEL
43 MD11Engineer: Actually we don't use diethylglycol anymore because of enviromental reasons. Most deicing fluids afaik use propylglycol, which is much less poisonous
44 BAe146QT: Thanks Jan - I didn't realise that it wasn't the same. It's just occurred to me that deicing must be quite an expensive task. Doubt the airlines pay a
45 HAWK21M: Amazing out here DeIcing is almost non Existing. regds MEL
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