Are the windows in the “top side” a “side”?

Huckster79

Huckster79

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Huckster79
i have a Cessna 140, the skylights are nasty... they let light in but you can’t really see clearly out of them... my question is on owner allowed maintenance side windows are on there, so is the topside a “side”? Or is side left and right vertically surfaces of fuselage only? So do I need an a&p to do it or supervise?
 
I just read through an owners manual for a 140 and the only mention of owner maintenance on windows was cleaning them. Can you be a little more specific as to your reference?

Replacement of skylight windows is almost certainly not owner maintenance. But if you have a good relationship with your A&P, there should be no reasone you wouldn’t be capable of doing the work and getting them to sign it off.
 
Huckster79 said:
my question is on owner allowed maintenance side windows are on there, so is the topside a “side”?
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"Side windows" typically refer to sliding/vent type windows that are installed with screws. While some skylights might be installed with screws they are usually considered part of the "structure" which falls under the "work does not interfere with the structure" portion of the 43 prevent mx (13). So it doesn't really fit under prevent mx especially if they are riveted in.

But before going through a replacement, have you tried any of the current plexiglass rejuvienators yet? They've made some great advances on the chemical side and I've seen a number of windows that cleaned up to the point where replacement was not neccessary.
 
bflynn said:
I just read through an owners manual for a 140 and the only mention of owner maintenance on windows was cleaning them. Can you be a little more specific as to your reference?

Replacement of skylight windows is almost certainly not owner maintenance. But if you have a good relationship with your A&P, there should be no reasone you wouldn’t be capable of doing the work and getting them to sign it off.
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The reference was from far 43 owner allowed maintenance says side windows... was hoping that basically meant: not the windshield... but yea if I gotta work with my a&p on it I’m sure that won’t be an issue... even if I do the removal and he does the install or whatnot as from what I can tell the install is the quicker step...
 
Bell206 said:
"Side windows" typically refer to sliding/vent type windows that are installed with screws. While some skylights might be installed with screws they are usually considered part of the "structure" which falls under the "work does not interfere with the structure" portion of the 43 prevent mx (13). So it doesn't really fit under prevent mx especially if they are riveted in.

But before going through a replacement, have you tried any of the current plexiglass rejuvienators yet? They've made some great advances on the chemical side and I've seen a number of windows that cleaned up to the point where replacement was not neccessary.
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They are screwed in- but I’m thinking that’s not technically correct... I did try WipeNew headlight restore on it-looks like crap... no worse than before but no better... the oxidation remover was 1500 and 2000 grit I believe and just added to the cloudiness, the wipe new liquid just makes them look wet... so they went from cloudy n full to cloudy and shiny...
 
Huckster79 said:
They are screwed in- but I’m thinking that’s not technically correct...
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If by that you mean the skylights should have been riveted in, it is perfectly acceptable to replace rivets with screws in some instances.
Huckster79 said:
I did try WipeNew headlight restore on it-looks like crap.
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My bad, I meant the aviation specific products like Scratch Off or the higher end products. There is one headlight lens product by 3M that has worked for me. However, if yours are real bad you'll likely have to use a restore system like Micro Mesh or equivalent. But since this is not a windshield I don't know if you get a better bang by buying the top products like Clear Fix which list over $200 for the complete system or replace the window. Aircraft Spruce deals in some of them--search under "windshield restore" or something close.
 
I have often wet sanded and then machine polished acrylic/plexiglas/polycarbonate if scratched or crazed. I consider it "cleaning" ...
 
Bell206 said:
If by that you mean the skylights should have been riveted in, it is perfectly acceptable to replace rivets with screws in some instances.

My bad, I meant the aviation specific products like Scratch Off or the higher end products. There is one headlight lens product by 3M that has worked for me. However, if yours are real bad you'll likely have to use a restore system like Micro Mesh or equivalent. But since this is not a windshield I don't know if you get a better bang by buying the top products like Clear Fix which list over $200 for the complete system or replace the window. Aircraft Spruce deals in some of them--search under "windshield restore" or something close.
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Yea at that price I'm better off buying new sky lights, they are $50 each or so, and if I can do most of the grunt work and have my A&P finish it up and sign it off it won't be a gamble if they come out clear...
 
Kenny Phillips said:
I have often wet sanded and then machine polished acrylic/plexiglas/polycarbonate if scratched or crazed. I consider it "cleaning" ...
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With what series of sandpaper grits? Machine polish?? on thin little window like that is a buffing wheel on the drill sufficient or would I need a true buffer? I burned my harbor frieght marine one up buffing the boat a few years ago... What did you use for the polish with the machine?
 
Huckster79 said:
They are screwed in- but I’m thinking that’s not technically correct... I did try WipeNew headlight restore on it-looks like crap... no worse than before but no better... the oxidation remover was 1500 and 2000 grit I believe and just added to the cloudiness, the wipe new liquid just makes them look wet... so they went from cloudy n full to cloudy and shiny...
Click to expand...
I once polished the cloudy plastic navlight covers on a Turbo Commander with Teflon polish, inside and out. It made them look brand new—for a while.
 
Huckster79 said:
With what series of sandpaper grits? Machine polish?? on thin little window like that is a buffing wheel on the drill sufficient or would I need a true buffer? I burned my harbor frieght marine one up buffing the boat a few years ago... What did you use for the polish with the machine?
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If it's really nasty I'll start with 400 wet-or-dry, then 600/800/1000, auto rubbing compound, auto polishing compound. Little buffing wheel on drill, or even by hand. Slow and steady, minimal material lost.
 
Kenny Phillips said:
If it's really nasty I'll start with 400 wet-or-dry, then 600/800/1000, auto rubbing compound, auto polishing compound. Little buffing wheel on drill, or even by hand. Slow and steady, minimal material lost.
Click to expand...

I may try that, as most of that I have laying around. I'm not going to spend big money the kits being if it doen'st work and two new ones cost a whole 0.1 AMU besides the little bit of install I may have to pay for the sign off I would be upside down trying to save em... But being those are things already sitting in the garage, I'll grab em and take em to the hanger and give it a shot... I'm thinking the wet sanding will chew through whatever nasty chemical coating that wipe new crap left on em...
 
is your Cessna 140 car3 certified ? might give some leeway in how you approach this project.
 
Huckster79 said:
I may try that, as most of that I have laying around. I'm not going to spend big money the kits being if it doen'st work and two new ones cost a whole 0.1 AMU besides the little bit of install I may have to pay for the sign off I would be upside down trying to save em... But being those are things already sitting in the garage, I'll grab em and take em to the hanger and give it a shot... I'm thinking the wet sanding will chew through whatever nasty chemical coating that wipe new crap left on em...
Click to expand...

I just wet sanded out some serious nicks and pockmarks (wing cover hook got loose) in my windshield with the Micromesh system and it worked great. But you can get similar results just with wet dry sandpaper. Just keep everything wet and use lots of water to clear off what's been sanded out. Super light pressure and let the sandpaper grit do the work. If you can get a 1500 or 2000 grit before the rubbing compounds, it is really quite clear.

Totally worth giving it a shot.
 
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