Sunday, August 8, 2010

The Work Begins In Earnest!

8/8/2010 - (Decided to add dates whenever I type) Up until now, I have done a little bit in removing the fabric of some of the various surfaces and removing paint from the fuselage, trying to work out processes etc.
I have decided to begin with the horizontal stabilizer as it has no internal working parts that will need any work. This also leaves me to concentrate on learning to properly apply the fabric covering without worrying about anything else.
Washing out the tail
The tail is large - 25 feet tip to tip and 42 inches front to back (without the elevators attached). It is so big I had thoughts of building a small fuselage and bolting it to the stabilizer and making a single seat aircraft, using the AN-2 tail as the wing. Just a passing thought.
After tearing off all the old fabric, I had a big mess on the ground. The Russians use cotton fabric, which only has about a 5 year life span. They have plenty of labor available, so recovering the plane every 5 years is not that big of a deal. I plan on using heavy weight poly-fiber material that could last 30 years or more. This job should only be done once in a persons lifetime. If the plane is still flying after I am gone, and my son has it and wants to recover the plane, good luck to him.
Unlike many other fabric covered aircraft, there is no rib stitching required to hold on the fabric. Along the top of each rib is a channel (refer picture) which houses a thin strip of soft aluminum. This holds the fabric in place. Easier and less time consuming to install, with the only problem is ordering the strips from Poland.
The cap strip and cross bracing
No stiching, but till lots of ribs to deal with
After peeling off the old fabric, I find that on the most part, the structure is in very good condition. All of the aluminum is alodized, with no corrosion evident. There are some steel cross bracing that has a little surface rust, but after a light rub with some 400 grit sandpaper, that comes away pretty quickly, leaving a smooth a shiny surface. My neighbor is an A&P with IA and thinks they will be fine. Just spray them with a corrosion shield and they should be ready to go for years of service.
The only other thing that needs doing is to clean off the glue on the leading edge and hinge areas. The only thing I have found so far is M.E.K. Nasty stuff! I have to wear a respirator and big gloves. Still, it melts the glue right away and then it is pretty easily wiped off with shop towels.

9/22/10 - Now that I am enrolled in an A & P course, I am learning much more about corrosion, (the killer of airplanes) what makes it occur, and how to avoid, or at least slow it down to acceptable levels. The benefit is that I am being taught how to be a licensed aircraft mechanic. The cost is very high in time, and will slow down the work. Oh, and by the way, the picture of me washing the stab shows lots of dirt in the yard behind me. Since then, with the help of all the kids, we finally got in grass, the sprinklers work and everything looks much better (but took a lot of time and energy). It has only been about three weeks, and the grass is growing so fast that I have had to mow it twice already. Hopefully it will start to get cold here soon, and slow the grass down a bit. I would rather work on the plane than mow grass!
I now realize that a more thorough inspection is required and as I am doing that I am still happy with what I am finding. Nothing so far to overly concern me. I now understand much more how different chemicals will react with the various metals, some in very nasty ways. I checked out the products I have used so far, and thankfully, all have been safe. At least I now know what to look for in chemicals. Even the wrong sandpaper can lead to corrosion problems later on. Who knew? And, 'Scrubbing Bubbles' is definitely NOT the right product for any type of metal surface, let alone an aluminum airplane.
Well, most of the glue and dirt is gone - at least on the side I can see - and I mixed up my first batch of epoxy filler to smooth out a few small dents and joints. It is great stuff and sets up really hard, but is easily sandable to smooth it out. Lets see what sort of a job I can manage to get a smooth surface. Onward and upward.

Monday, August 2, 2010

In Utah



Unloading in Nephi
A couple of big birds in the hanger
For a little while we had the use of a large hanger in Nephi, but after a few months the owners wanted to double the rent, then double it again (which would make it $2000 per month), so we were forced to find a new home for the plane as we couldn't afford that much money. This hanger was so big that we could fit both Tom's and our plane into the hanger.
Tom had to travel down from Salt Lake City, which was close to one hundred miles each way, so although it was a great facility, it was hard for him to get there. He then decided to take his plane back up to SLC. Then when we had to move out of the hanger Tom moved his back up to his workshop where he ran his business from. Not ideal but a lot closer. I think shortly after that he sold it and moved on to a different project, but not too sure about that.
Heading out from Nephi
It was nice having that space, and being able to work out of the weather, but with no rich uncles to support our pricey habit, we had to move the plane again. This time we would do it ourselves, without the semi trailer and cranes. The destination was Spanish Fork, and I remembered that the previous owner had lifted the tailwheel into the back of a pickup and just towed the plane down the road in Seattle, from the dockyards to the airport. So that is the way it would make the 40 mile trip up to Spanish Fork. As the main gear is 12 feet wide, we were able to get a wide load permit and haul it down the freeway. What a sight. Cars passing slowed down and cell phones became cameras for an unbelievable picture. The truck/plane combination tracked well on the road, and we arrived back in the Springville - Spanish Fork area without any problems. Our destination was a block building that was basically disused, but large enough to keep all the parts out of the weather. We were able to barely get in the door - with about 1/2 inch to spare - after letting some of the air out of the tires.
Squeezing in the door
A few months later, I  decided to move the plane down to the SF airport, so I could start work on it. The building it was in had no power or lights, and no way to do any work. First I moved it to the backyard of my house for a while, then down to the airport. At the airport it would have to again be stored in the open, but at least I could get some work done. Parked at the end of a row of hangers, it became a landmark for the helicopter school pilots to line up with as the came in to land.
After most of the winter there, we built a house in Santaquin and moved it to the backyard of our new house. There were only one or two houses in the entire subdivision, but the HOA did not like have the plane there at all, so after several threatening letters over a few months, I finally found a small private airstrip over the hill from my house where the fuselage could sit in peace until time to work on it. The wings are in a storage unit and at the house and now it is time to get to work in earnest.

Sunday, August 1, 2010

The Tear Down.

Some of the control surfaces

As none of us had ever worked on an AN-2 before, we just started at one end and kept pulling parts off until we had something we could transport. We started with the tail and moved forward to the propeller blades. Luckily, the cabin is huge and all of the ailerons, flaps, elevators, fin and rudder fit inside the plane
The AN-2 is big, bulky and solid, yet very simple. It is easy to see why it is so successful as a backwoods aircraft. Apart from its carrying capacity (approx 5000lbs payload), short takeoff and landing capacity (200ft takeoff fully loaded) and rough field performance, it can withstand a beating yet be serviced easily. I was told a story of a pilot that flew one on skis performing an air ambulance mission in the middle of the Russian winter. The remote village where he had to pick up an injured farmer did not have an airstrip, so he landed on the frozen river. Before they could take-off again, a storm closed in. Yet the patient needed to get to the hospital as quick as possible. So the pilot taxied the aircraft 80 km (50 miles) down the frozen river until he was out of the storm and able to take off. That would require a great plane and big brass ones on the part of the pilot.
Sarah taking a break
For 4 days Sarah, Tom and I pulled the 2 aircraft apart, piece by piece. As we discovered something new, we would relate it to Tom and vice versa. Fairings came off quickly, then the rudder, fin, elevators, horizontal stabilizer.
Then we started on the wings.As these were much larger and heavier, it took us a while to work out how to do these. First, all the flying wires needed to be undone. These hold the wings in the right position and as we started to loosen them, the wing started to droop. So we had to prop up the set of wings from under the bottom wing in line with the struts. Then once the wires were removed, we could undo all the attachment points of the bottom wing. Then we had to bring in the crane on Toms truck to hold up the top wing, while we removed the bottom wing and strut. Then once the top wing was undone from the plane, we could lower it using the crane and a forklift. Keep in mind that this wing weighs over 600 lbs and the wingtip is about 14 feet off the ground. Slow and steady was the order of the day.
Taking off a blade
After all 4 sets of wings were removed from the 2 planes, the propellers came next. Each blade is about 6 foot long and weighs about 100 lbs, and is attached by a very large thread on the hub end. I built a tool out of a couple of 2x4's bolted together to wrench the blades out of the hub. Tough job. But persistence won in the end. I hope there is an easier way to get these back in.
Now all that was left was to lift the plane and take off the gear, load it onto a truck and strap everything else down, then drive home. Easier said than done.
Without everything else attached, the fuselage still weighed close to 6000lbs. It was all Toms' little crane could handle, so at least we didn't need a larger crane. With it off the ground, it was now possible to remove the gear and then lower it onto a flatbed. The fuselage is 41 feet long, so we were able to get away with a 40ft drop deck trailer. Some guy came by who had moved one before said that there was no way that we could get it all on to one trailer, but we did it.
On the truck
With the fuselage on, we stood the wings upright and strapped them onto the fuselage. Having holes in the fabric, and being able to add more when we needed them sure made it easy. Lots of old tires protected the leading edges,  and straps and rope all over the place. But it all held together for the 900+ mile trip home. No damage!



Strapping down the wings
The truck driver told us that this was the most interesting load he had ever carried, if that can be judged by the looks and comments he received on the way.We wanted to travel with the truck, but he was stopping half way for the night, and we had to hurry home to organize a crane at Nephi airport to take the plane off the trailer as Tom had to go back to work and wouldn't be in Nephi for a few days. The whole deal was a lot of hard work, yet great fun and a very steep learning curve. In fact we did so well that we got asked to pull another one apart and send it by boat up to Juno, Alaska.

All packed up and ready to go!
Check out the slide show for a lot more pictures of the entire adventure!

Aquisition.

Side view looking in to the huge interior
Sarah (my daughter) and I chose the plane we wanted  It had been built in 1985, and had less than 2000 hours on the airframe and only a couple hundred hours on the engine. The fuselage was in fair shape, although all the glass would have to be replaced. The fabric surfaces were all rotten and the plane would need a total recover job. The engine was (and still is) a total unknown, after sitting in the humidity of Seattle for 10 years without any protection. The interior was totally unlined and had 12 military style metal fold down seats attached to the sides. Static lines run fore and aft, and it has jump lights in the rear of the cabin, so at some point it was used as a jump plane .
We discovered later that our plane had been in service with Aeroflot and another air service as we stripped the paint off the fuselage. In Russia, it seemed that if the plane needed a new paint job, they just kept building it up layer on layer over the old one. We found at least 2 sets of markings under that blue and white paint scheme. Most of the paint was pretty chalky, and we wanted a military scheme, so the existing paint would have to come off.
Another buyer from SLC was there at the same time and he had an oil service business and had brought his truck with him that had a small crane on the back We decided to help each other pull the planes apart and load them on trucks for the journey. The 3 of us took 4 days to do both planes. While we mostly worked on our own planes, any time we needed extra hands, we all worked on that plane.
One of the flaps on the lower wing was binding a little, so we cut off some of the fabric to have a look. The push-rod had a slight bend in it, and was binding on the hole in the rib it passed through. I showed the Russian guy we were buying the plane from, and asked him how easy it would be to get a new pushrod. He said all we had to do was get a hammer and make the hole in the rib bigger so it would not bind any more. We decided that we would order a replacement push-rod from Poland instead.
The plane is built like a tank. Some of the fittings look like they could be from a bridge rather than an aircraft. Very solid. I guess WWII designs were on the most part overbuilt to provide combat survivable strength and this was designed and first built just after WWII.
We had the opportunity to fly in the demonstrator on a day trip to the Arlington Fly-In. I flew right seat on the way back. You know you are flying a BIG airplane when the pilot flying not only hands control off to you, but then gets up and walks out of the cockpit (without crouching). 
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Discovery.

In 2006 a buddy told me about some AN-2's that were available. He had not seen them but was flying to Seattle on business and would check them out while he was there. He had heard that the fabric was a little rough, but his intention was to do some duct tape repairs and fly one home. Did I want to join him in this project?
The flyable demonstrator
When he want there and saw the shape they were in, he realized that his duct tape plan was not going to work. The plane would have to be dismantled and trucked home and then go through a full rebuild.
I had only seen an AN-2 once years before, and all I could remember was that they were pretty ugly. So after checking out a few pages on the internet, I thought it might be 'fun' to give this project a go.
I loaded some tools and my daughter in the car in June 2006 and headed up to Seattle for my first look. As we pulled into the little airfield where they were stored, both our mouths dropped as we saw the monsters parked next to some little toy (by comparison) airplanes: Cessna's, Piper's and such.
Yes, the one in the above picture looked pretty good, in fact, it was in flying condition. Unfortunately, all the others were not in the same shape, and the 'good' one was not for sale at the time. 10  AN-2's had been brought over from Russia but only one had been reassembled and flown as the demonstrator. The others had been hung together, but nothing tightened. Then they had sat in the open Seattle weather for 10 years. A few had been sold but the others were slowly rotting. The airport management were threatening to bulldoze the remaining planes if they were not removed quickly.
For those of you who don't know much about AN-2's, they were designed in 1947 and built first in Russia, then in Poland - by PZL - right up until the year 2000. Over 20,000 were built, with the main difference in all models being the radios. Powered by the 1000hp Russian version of the P&W 1830, basically the same engine as in a DC-3, the AN-2 is a  bi-plane with 60' wingspan, with leading edge slats on the top wing and full flaps on both wings. It can take off and land in such a small distance it should really be classed as a helicopter.
An interesting note from the pilot's handbook gives some idea of how solid this plane is built and, despite it's size, how much lift is generated by the huge wings. It reads: "If the engine quits in instrument conditions (blind flying when you can't see the ground) or at night, the pilot should pull the control column full aft (it wont stall) and keep the wings level. The leading-edge slats will snap out at about 40 mph (64 km/h), and when the airplane slows to a forward speed of about 25 mph [40 km/h], the airplane will sink at about a parachute descent rate until the aircraft hits the ground."