More Sawdust

Work on 53T continues...We filled up the propane tank last night so we're back in business.  Tonight I finished cutting out and getting a rough fit on the big rib so now all the ribs that were removed from the right wing have new replacements.  They look good and the next step is to get them epoxied in place.

While I've been doing this rib work i've been eyeing the trailing edge behind the airbrake.  There is some twisting going on as a result of oversized return springs used on the airbrake.  This torqued the middle rib that runs through the airbrake area.  Of course we replaced the right hand rib.  The left hand rib in the airbrake area was also twisted. Guilt by association I suppose.  Anyway I figured if I could cut out the trailing edge in that section I could have a chance at getting the ribs sorta straight again and back in place.  So, now 3 feet of trailing edge on the right wing are missing.

Looks like it's time to make another order from Aircraft Spruce...

Cherokee II Pictures from the San Diego Air & Space Museum

I was just googling around and ran across these, which I've never seen before.  According to the pictures it was built by Duke Stallings, I'm not sure if it was ever completed. I don't recall seeing a canopy quite like that before.  Will have to do some research...Pictures start here: http://www.flickr.com/photos/sdasmarchives/4589752619/in/photostream/

Cutting Ribs

I haven't made many updates in the last few weeks because we haven't been getting much work done on 53T.  Some winter prep work around the house and in the garage has been my focus.  Specifically i've nearly finished the last bits of insulating that needed done on the walls of the garage.  We'll need to finish the last few pieces of sheetrock on the ceiling so I can finish insulating the season. 

I have had a few chances to cut out a few new ribs for the right wing.  I have two false ribs and the one big main rib remaining to be cut.  Then of course we'll need new skin and filler to get everything smoothed out.  I'm starting to contemplate replacing a section of the trailing edge to attempt to take care of some ribs that are warped.We'll see...

Update

Last week I did manage to get to the garage a few nights. Matt came over to help and he cleaned the balsa facing off the left airbrake and removed both airbrakes.  The hinges have some pretty decent corrosion on them.  I kept working on the ribs on the right wing.  New plywood arrived and the new rib shapes are traced out and ready to cut. I also received a package with a full set of ribs as well as metal fittings from Richard Beck. Thanks Richard!  I used the rib in that package to make a template for a new rib to replace the one true rib that I removed on the right wing.  So this week the goal is to make some sawdust and start putting parts back in the glider.

Yesterday we got 3Y out for the last day of scheduled operations at the club.  This was the first time I have flown 3Y at Sunflower since my first flight in it this spring in May, when Summer and I landed out.  Needless to say we have been on the road a lot with the glider this season. I added up the logbook and I think I had just over 50 hours in it this season. Not bad!  Lift yesterday was weak and broken up, we had two flights, first one about an hour and the second one right at half an hour. Here are the traces:

http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2154811

http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2154816

Leah and I received some sad news on Saturday.  Bud Brown, builder of 4653T, passed away on Friday.  Awful news as I was very hopeful to get to meet him one day and show him 53T once we're finished with it.  Here is Bud's obituary:  http://www.emmonsmaceysteffey.com/sitemaker/sites/Emmons1/obit.cgi?user=501088Brown

Destruction complete, I think

Tonight I worked a bit to remove the broken rib.  First, however, I was able to get a good look down the leading edge of the right wing thanks to the false ribs being removed.  there was a bunch of mouse nest leftovers outboard of the hole I cut so I spent some time with the shop vac cleaning the wing out.  Managed to remove everything I could see.  I also was able to get a good luck at the adjacent rib bays and determined that I didn't need to remove any more skin which is great!

The last thing I did tonight was remove the main rib that I broke while removing skin.  It didn't cause too much trouble.  For now at least this is the last phase of destruction in this section of the wing.  There is a chance I might end up re-working the trailing edge but that won't come until the rib repairs are complete.  Here is a photo:

Removal

Harry stopped by to inspect the damage last night.  He thought most of the ribs were probably OK and could be saved with some doublers.  I had already removed the blantantly broken false ribs as those will be pretty easy to replace with new.  Matt G came over to help and hit the not broken ribs with the sander to clean them up so we could see what we were dealing with.  Both false ribs that weren't broken showed some pretty major cracking into the plys that was more than just the surface, so it was a pretty easy decision to remove them.

The main rib next to the airbrake box is also broken so it will probably get removed and replaced. I've ordered some plywood to cut new ribs.  Here are some pictures of tonights destruction:

Opening Right Wing

 I started off tonight with the intention of squaring up the hole that I cut in 3T's right wing so that a new piece of plywood could be scarfed in to replace it.  While doing that I looked towards the tip inside the leading edge and noticed that the next false rib was blatantly broken.  So the hole went from this:

to this:

Not too bad I thought. However after looking at that rib, and noticing that the false rib next to it was also broken, I realized the easiest way to fix them would be just a complete replacement.  The break was on the top back near the spar, not to mention the leading edges of all the ribs are in questionable shape thanks to the mouse damage.  I also found some more mouse nest material in the new rib bay that I opened up and vacuumed some more out of the next bay towards the tip.  So, I decided to remove the skin in the newly opened bay back to the second spar on top so the false ribs can be replaced.

Next I started careful work with the chisel to square up the aft edge of the original cutout.  I noticed that one false rib was cracked which I wasn't particularly excited about.  Then I managed to damage the real rib which forms the tip-side border of the airbrake box.  That was it.  The rest of the skin was coming off so I had full access to all the ribs in this area.

And thats where I stopped for the night. 

Jacob was over earlier and we got the rudder cables finished and also he worked on sanding down the filler work we had done the other night. For the woodwork, next thing I suppose is to evaluate what to do with each rib in this area.  Most of them are going to need some form of repair or replacement.  Then I'll have to order some plywood and go to town.  All the ribs on the Cherokee II are sawn from 1/4" marine plywood.