Rebuilding the 2-33 - Part 2

Today, Bryan and Caitlyn Reigal, Kevin and I stripped the fabric from number 3.  Dave Welles stopped by to help and Ed Funk got us started but was feeling poorly and had to head home.

As the time lapse video above will attest, it didn't take long to get the bulk of the fabric off of the fuselage.  A utility knife and a little peeling took care of it easily.  Underneath was mostly the metal frame, but in some spots the fabric, or the impression of the fabric remained on the metal framework and we did what we could to scrape it down.  Other remnants included old and crumbly bits of tape that wrapped the frame and were underneath the fabric.

We also removed the fabric from the rear control surfaces - the horizontal stabilizer and the elevator (the stabilizer is fixed, the elevator is the moving part) and the rudder.

Between our last visit to the shop, Dave Welles and Shaw Siglin had removed all of the controls - the rudder pedals, cables, control sticks, spoiler actuators and so forth.  They also removed the fiberglass nose from the frame.  

At this point, the fuselage looks pretty bare and is ready for K&L soaring to come take a look at it and let us know how much the glass bead blasting and restoration of the frame will cost.  I haven't noticed much obvious rust or pitting on the frame, so I'm hoping that its years in the hangar have helped to extend #3's life quite a bit.

Next steps for us are to inventory the interior parts and decide what kind of repair, rework, or replacement needs to be done.

More pictures in my Soaring directory: https://picasaweb.google.com/tberry0916/Soaring

Rushing to takeoff

I saw the following quote in Flying magazine and it spurred some thoughts:

"Do not let yourself be forced into doing anything before you are ready." 

— Wilbur Wright

Another good quote: "Aviation, to an even greater
extent than the sea, is terribly unforgiving."
- anonymous

Happens to our pilots before takeoff in three ways - 

1.  The pilot doesn't get into the aircraft soon enough.  We usually go over this one at the safety meetings.  I've found over time that if I'm not strapping in when the glider in front of me is taking off, I don't feel that I have comfortably gotten my head in the game.  It only takes one twisted seatbelt strap to cost you a couple of minutes and before you know it the tow plane is taxiing up and you haven't even started the pre-takeoff checklist.

2.  Corollary to number 1, above - people don't realize that with two tow planes, you need to already be strapped in with the checklist complete BEFORE the plane in front of you takes off.

3.  Commercial pilots - strapping a passenger in, giving them the briefing, and then strapping yourself in and doing the checklist takes longer than you think.  Even with one tow plane, if you greet the passenger before the glider in front of you takes off, you are in a race to be ready when it comes back.  It's simply unavoidable that you will delay the tow plane in some instances -especially if they haven't brought the next passenger down already.  This happen often when you have two or even three commercial pilots flying - the cash position doesn't always know to keep the queue full even if the log person is on top of it.  It is helpful to have a ground crew strap in the passenger -very helpful, but even so, you can still end up with the tow plane waiting through no fault of your own.

Thus, at some point, you will almost *always* end up with the tow plane waiting on you while you strap in.  This is when you forget to lock the canopy or don't remember to check the passenger's weight and let them sit in the front.  I've read enough Aftermath articles in Flying to realize that getting rushed unnecessarily is a BAD idea.  The solution?  In this case, you control the tempo.  Take as much time as you need, and as little time as you can and tell the towplane to shut down if necessary.  Unless Heinz Jr. is flying.  Then don't make him wait for anything.  Kidding.  I'll make him wait too, if it means not missing an item on the checklist.

Obviously, we should do the things we need to do so we don't put ourselves in a rushed takeoff situation.  But my ADM says that if it *does* happen, be conscious that it is occurring and take the necessary time to do things right and prevent the issue the NEXT time you takeoff.  According to a chart I found on the O-540 engine, a Pawnee consumes about 10 gallons per hour or .16 gallons per minute.  If you take an extra 3 minutes, that's a 1/2 gallon or $3.25.  Not chump change, but probably worth the cost of ensuring something bad doesn't happen in flight.  Just make sure it doesn't happen again. 

Rebuilding a Schweizer 2-33 - Part 1

Number 3 is wheeled out to the line to provide faithful
service in training new pilots.

The board of directors voted to refurbish one of the three Schweizer 2-33's that the club owns recently.  Number 3 has needed some attention this summer as it developed a rip in the fuselage fabric and as you might imagine, after almost 40 years of flying it could use an overhaul.

The bulk of the work concentrates on the fuselage and today we spent a number of hours removing the rudder, horizontal stabilizer, interior, wheel, and skid from the aircraft.

Thanks to the National Soaring Museum for letting us use their restoration shop to do the work!

The fuselage is the main focus

The wings are stored in the restoration shop as well

The wings are in pretty good shape because we are fortunate enough to be able to store our aircraft in a hangar for the majority of the time.  So, when the time comes we'll give them some TLC to clean them up, wash them off, wax them and so forth, but there's really no need to paint them.

That's not to say they don't have a number of  'hangar rash' spots that come from years of club members moving them in and out of a crowded hangar.  But since many 2-33's are stored outdoors, their aluminum wings often require repaint from sun and rain exposure.  We are very lucky that isn't the case for us.

My son Kevin and I are assigned to the interior strip and removal.  Although I've spent my share of hours inside a 2-33, I didn't realize how much stuff there is inside the cockpit!

Many of the parts and innards of a 2-33

The picture at left is the parts rack of stuff we've taken off of the aircraft.  The control surfaces (rudder, elevator, horizontal stabilizer) are on top while the second shelf contains most of the stuff Kevin and I stripped out of the front and rear cockpit.

Sidewalls, floorboards, seatbelts, seat pans and seatbacks, control stick boots, and trim all came out to expose the innards of the 2-33.  It was really quite cool to finally get to see the inner workings of the glider and appreciate the simplicity that makes the 2-33 so reliable even 40 years on.

Before we began taking number 3 apart

I took a couple of pictures at the start so we could remember how and where everything goes when it is time to put it all back.  At left, looking from the rear cockpit to the front is the complete package.

By the time we finished in the afternoon, the interior was down to the bare bones.  The only thing left were the rudder pedals and control sticks.

Stamped on the back of an interior sidewall piece was
Run #21handwritten.  I turns out to be our own Corky
Gill's Schweizer inspection number.

Same view (looking forward) after stripping the interior

Did we find anything interesting inside after all this time?  We did, stamped on the sidewall of one of the trim pieces.  I was looking at it and noticed the handwritten "Run #21" among the various manufacturing stamps.  I read it out loud and  then heard, "Hey, that's me!"

Corky Gill, one of our senior club members worked at Schweizer until the early 90's and his inspection number was #21.  I showed him the handwriting and he confirmed that it was his!

Corky Gill's (in the red hat) inspector number rides inside #3.
Dave Welles, at right, was a test pilot at Schweizer.

What's next for number 3?  Well, after we strip the fabric, it will be off to K&L soaring for a fuselage inspection and reconditioning to ensure we don't have corrosion in the tubular framing.

At the nose, looking aft.

Following that, we'll have #3 re-covered and put it back together again.  We'll ensure any slop is taken out of the controls, replace any instruments that need help, and clean and paint the interior.  For all intents and purposes, the fuselage will be brand new.  And since the wings are in good shape, number 3 will be given new life to train our pilots at Harris Hill next summer.

Kevin and I really enjoyed stripping the interior and seeing how the 2-33 works.  It's nice to have a project to keep us busy over the winter season and I'm looking forward to flying in number 3 next year!

More pictures of the restoration are here.

RASP - Improving our Soaring Forecast

Output of a typical RASP run.
Source: Valley Soaring.net

"Do you know what RASP is?"  It was a question from one of our best sailplane racing pilots.

I told him I didn't really know what it was.  It turns out to be a soaring prediction model called Regional Atmospheric Soaring Prediction, or RASP.   The RASP model turns out what are called blipmaps which are maps of soaring conditions that indicate all kinds of parameters of interest to soaring pilots.

These maps are already available online at www.drjack.com, but the grid areas are large and the terrain isn't considered as precisely as it could be.  Dr. Jack Glendening is an atmospheric scientist and the author of RASP.  He allows gliding clubs to use his code at no charge, but also with community-only support.

I took a look at RASP, which is a collection of Unix programs that are controlled from an overall RASP script.  It is a terminal only program - there is no GUI, and all output during the runs is written console-style to logs that you pore through to determine the source of your errors.  Parameters are in different directories and not always obvious.  The documentation for the program is fairly robust, but suffice it to say that troubleshooting a complex software package that you have never seen before is quite a challenge.

So far, I've managed to get RASP right up to the edge where it actually run the atmospheric forecasting program.  In effect, the program so far downloads the results of model runs from the National Weather Service, then preps them for a local run of WRF, the Weather Research and Forecasting model.  That's where the hard number crunching happens, then the results are output in a format you can put them on a website with graphical charts showing the results.

I've come quite a way to make just a little progress and I'm currently stumped at one error.  The forum for RASP is understandably small and Dr. Jack doesn't actively support RASP, so if I can't figure it out, I'm sunk.  I've got one or two ideas right now, but right now I'll give myself about a 70% chance of success.