Mooneymite Posted April 12, 2014 Report Posted April 12, 2014 When I first got the plane, I looked frequently. However, now that I've had the plane for years, keep the plane in the hangar, and haven't found corrosion in other places, I check "periodically". To me, it's kind of like SB 208B (called for annually)....how often is "often enough" depends a lot on the environnment and the general condition of your aircraft. 1 Quote
scottfromiowa Posted April 12, 2014 Author Report Posted April 12, 2014 Can someone tell me what line of the Mooney 100 hour maintenance checklist addresses removal of the the rear seat and visual inspection of the spar? Thanks, Scott Quote
Marauder Posted April 12, 2014 Report Posted April 12, 2014 Scott - I think this section talks about internal inspection for corrosion. I haven't checked the manual for the details. Quote
Marauder Posted April 12, 2014 Report Posted April 12, 2014 Just pulled up the referenced service manual. Section 8 speaks about corrosion detection and treatment. Here is reference to the rear seat Quote
FloridaMan Posted April 12, 2014 Report Posted April 12, 2014 Can someone explain the procedure for removing the rear seat? After seeing that thread about the "C" model, I'm going to go check on my airplane. 1 Quote
scottfromiowa Posted April 12, 2014 Author Report Posted April 12, 2014 Marauder, thanks for your post. I am trying to learn...that said I am not interpreting the information to mean you should be pulling the rear seat and inspecting the spar with an annual inspection/100 hour inspection. I too would like play by play to remove rear seat cushion to "see" the goods underneath for myself. The one area I have NOT seen on my plane that has been hangered all its life...or so I was told (It was one owner). I have had corrosion X applied to wings and tailcone every other year for last ten years. My tailcone is "messy" with Corrosion X and weeps it for a about six months after application...I have inspected the tubing as has my A&P with interior removal/windows change/re-do of insulation... Quote
Marauder Posted April 12, 2014 Report Posted April 12, 2014 I think like any manual there is a certain expectation that the professional (A&P) use judgement on where and how to look for corrosion. Section 8 is packed with a bunch of comments about inspecting for it throughout the plane. The spot under the rear seats is a low area and something as simple as a spilled drink will migrate under the seat. Just like SB208, I think there is enough evidence with the fleet that it should be checked. All I do know is that I will be asking my IA to verify the condition at the annual. I have pulled the rear seat a few times to look for loose screws from upgrades. Not sure if the annual inspection is doing the same thing. 1 Quote
scottfromiowa Posted April 12, 2014 Author Report Posted April 12, 2014 Step by step process on rear seat removal appreciated... 1 Quote
scottfromiowa Posted April 12, 2014 Author Report Posted April 12, 2014 Extra credit for photos... 1 Quote
Marauder Posted April 12, 2014 Report Posted April 12, 2014 Can someone explain the procedure for removing the rear seat? After seeing that thread about the "C" model, I'm going to go check on my airplane. I'm seat pulling tomorrow and will write up what I did if someone doesn't respond sooner. I seem to remember a couple of cotter pins but it has been a few years since I pulled it. 1 Quote
scottfromiowa Posted April 12, 2014 Author Report Posted April 12, 2014 I appreciate the honesty on the poll....I would love to see some photos of your spar with seat removed... Quote
scottfromiowa Posted April 12, 2014 Author Report Posted April 12, 2014 I'm seat pulling tomorrow and will write up what I did if someone doesn't respond sooner. I seem to remember a couple of cotter pins but it has been a few years since I pulled it. Wish I was close by. I would enjoy apprenticing on this. 1 Quote
DaveL Posted April 12, 2014 Report Posted April 12, 2014 I can take photos later, but removing the seat is a very easy 5 minute job. The bottom cushion (C model) has a flap across the front that simply hooks behind a series of clips. Using fingers one just unhooks the rod, and then the seat bottom pulls out. The seat back has four bolts - again very easy to see and get to. Once that's out one needs to peel the aluminum tape off a series of inspection covers and remove some small phillips screws from each. The rear spar is easily seen through those panels. I think it might take 45 minutes at best to do the inspection including removing the seat and panels. 1 Quote
scottfromiowa Posted April 13, 2014 Author Report Posted April 13, 2014 Can corrosion protection be sprayed from belly below to access this area? Quote
DaveL Posted April 13, 2014 Report Posted April 13, 2014 Can corrosion protection be sprayed from belly below to access this area? Yep, but it's much more work to remove the belly panels than it is to remove the seat in my estimation. Quote
N201MKTurbo Posted April 13, 2014 Report Posted April 13, 2014 I'm glad I live in Arizona. Nothing corrodes. That's why the Air Force and the airlines park their unused planes here. Well also because our ground is so hard that a 747 or B52 wont sink when parked on the dirt. 2 Quote
Mooneymite Posted April 13, 2014 Report Posted April 13, 2014 I'm glad I live in Arizona. Nothing corrodes. That's why the Air Force and the airlines park their unused planes here. Well also because our ground is so hard that a 747 or B52 wont sink when parked on the dirt. So, true. However, not all planes are "born and bred" in Arizona. Pity the poor guy who buys a dry, Arizona aircraft only to discover it spent the first 15 years of it's life in a sea-side resort and has intergranular corrosion in all the wrong places. 1 Quote
FloridaMan Posted April 13, 2014 Report Posted April 13, 2014 I had a piece of carpet in the front of my rear seat that had four screws that I had to remove. The rod is easiest to remove/add when you're sitting on the rear seat. Then I had cover panels to holes that I had to dip my iphone into to take photos. Photos to come. After seeing that thread about the C model, I ran to the airport and immediately figured out how to get under the seat. Quote
Andy95W Posted April 13, 2014 Report Posted April 13, 2014 But wait, there's more. There is another thread going "Just found out my C is junk" that is more specifically about the stub spar assembly. This smaller spar is located to the rear of the back seat/forward edge of the baggage compartment and further outboard becomes the rear mount for the main landing gear pivot points. These are notorious for accumulating moisture and then corrosion, so much so that in the 70's Mooney started painting them with good corrosion resisting paint. For all pre-201's, I'll bet that most have at least some corrosion that is on the verge of full-blown intergranular corrosion of the extruded angle aluminum. This is extremely difficult to inspect for and requires some contorting with an inspection mirror, or removal of the baggage floor. I inspect this stub spar every annual and go nuts with the Corrosion X on it. BTW, I have rarely found significant corrosion on the main spar, but it is scary how often I have seen corrosion to one degree or another on the stub spar of airplanes I've inspected. Quote
N601RX Posted April 13, 2014 Report Posted April 13, 2014 With a once piece belly it isn't necessary to remove the seat bottoms. With the belly removed you can easily see the back side of the spar from the under side. There is also a small triangular area behind the very end of the rear spar that is very difficult to see. The nearest access panel is almost 3 ft away and you have to look through a hole in the rib to see into this area. I found a rat nest in that area that had been missed for many years, luckily there was no corrosion. Quote
carusoam Posted April 14, 2014 Report Posted April 14, 2014 The seat flap and the rug are an interesting combination on the C. This is where I found the beginnings of corrosion in mine It is also the place where messes are made and collect. Was that a soda spill? It is also the spot where dirt and wear take a heavy toll. Coatings get 'sanded' away. It is also a place that is infrequently visited by the pilot. He never sits there while flying... I never held the flap down (missing aluminum piece), and the rug was not secured in back. They got pulled up for a monthly or quarterly cleaning of some type. Annual was the time for viewing the other sides of all spars. Stored outside, it got fogged with corrosionX on a schedule. Best regards, -a- Quote
Sabremech Posted April 14, 2014 Report Posted April 14, 2014 I look at mine probably every other year. I'm not adding any Corrosion X as I plan on painting my airplane in the next year or so and it's still being pulled out through skin joints in the wings and fuselage. I'm concerned of the trouble I'm going to have getting a good clean surface for primer and paint. David Quote
carusoam Posted April 15, 2014 Report Posted April 15, 2014 David, Is it escaping through your rivets as well? Can make them look like they are smoking... Best regards, Quote
Lood Posted April 15, 2014 Report Posted April 15, 2014 Never done it myself, but my AME remove all seats and floor mats, etc, every year during the annual. Not sure whether it's requirement, but good to know that they pull out everything and look everywhere. Quote
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