Day 7--The Engine that Baffles, wings, ailerons, and avionics!

Hi everyone, welcome back!

As we expected, today was a busy day.  We are a little behind schedule after the airshow and are pushing to make up time.  Today Tracy spent most of the day on the Engine baffling and attach points, and i worked mostly on the fuel lines running from the wings to the fuel boost pump, then out to the engines.  But we got a lot of other things done, too--the tailwheel finished (and taken off for later use), the flaps & ailerons mounted (but not attached to the control cables yet).  Perhaps the most exciting part of the day was the arrival of our avionics package!  Pictures to follow...

Finally, a finished tailwheel!  You can see the steering cables attached to springs, then the wheel.  Alas, as soon as it was finished, we took it off.  We won’t see it on the airplane again until October.

This is the fuel boost pump.  It goes between the rudder pedals.  We use the pump during takeoffs and critical climbs—basically high power, high-fuel-demand phases of flight.  It really shouldn’t be needed and is most often bypassed, but it adds a safety of flight factor.

Here is the boost pump up close.  Sometimes simpler is better—it is simply zip-tied to the airframe (heavy-duty zipties, of course!).  Here you can easily see the bypass (the silver pipe traveling left of the pump).

Once the boost pump was in, we had to connect the wing tanks to it.  Doing this requires solving a 3D jigsaw puzzle of pipe bends.  Here are the three pipes we hooked up, and all the pipe-bending tools.  The entire fuel line routing goes from the header tank (a 1qt tank that keeps fuel flowing smoothly during any aggressive maneuvering) to the floor, back to the fuselage sidewalls, around & under the seats, then up into the fuel selector valve.  Like a roller coaster.

Here is a shot of the pipes coming into and out of the fuel selector valve.  The single pipe that connects them is exactly 5 and 1/8 inches long…I know this because I cut the first one to 5 and 3/8 inches and we had to redo it.  We couldn’t fit any pipe-bending tools in the space there so I bent the piping by hand.  Good times.

Tracy spent most of the day working on the engine.  This was more difficult than expected due to parts of the baffling not quite fitting right.  Here she’s safety-wiring the air intake manifold.

And here it is.  She rocks!

Tracy said carving this baffling with a combination of saws, sanders and polishing wheels took her about an hour.

Here she is installing the baffling.  The baffling is a heat shield that keeps exterior lines from getting too hot in the engine compartment.  It is part of the cooling system and helps route outside air into the hottest parts of the engine (like most General Aviation Engines, ours is air-cooled).

Here is the baffling installed except for the forward plate.  One of the nice side benefits of the baffling is the nice clean look it gives the engine.

We got our avionics panel today!  It’s important for us to throw it right in the airplane, because a lot has to be hooked up to it.  Our avionics will outpace our other airplane by about 25 years of technology.  When they are hooked up I’ll post some more pictures of them.  Our panel is designed for cross-country travel under Instrument Flight Rules—basically, flying through weather as long as there’s no lightning or icing.

Here’s the back of the panel.  Oh my goodness.  What does that wire do again?...time for me to go back to school.  The clamps on the panel are where we left off today.  We are adjusting the panel to be 90deg perpendicular to the aircraft waterline.  This will help us align the gyroscopes in the avionics system later on.

Okay party people, that's it for today.  Thanks for following along and See you again tomorrow!
-zen

Day 6...the Sportsman has landed!

Hello all, & happy weekend!

Today was a great Saturday!  Although there were only 4 of us working today, we got some of the big exterior portions of the airplane finished--like the main gear and the wing fitting.  Our airplane looks like an airplane!  It was a hoot--as the airshow raged on right outside the hangar, we put wheels & brakes on, lifted wings, and worked some more on the tail section. 

Also today, our friend Casey "Rogue" Hughes stopped by to check out the build, as he was in the area.  It was pretty awesome to climb out from under the tail and see a familiar face!

Last, we were able to get over to the airshow at the end of the day, so I took a couple more pictures of that.  Tomorrow is a day off of building for us--we are going flying instead!  We are going to take our first hop in a tailwheel-configured Sportsman, to begin to learn how to fly it right.  Should be a good time--I'll post a few pictures of that, too.  Hope you're all having a great weekend!

Wheels on!  Unlike a car wheel with multiple nuts on the spoke, the airplane wheel is only held on with a single nut over the main gear axle.  Hence the cotter pin!

After the wheels were on, we put the brake calipers on them.  This safety wire job keeps the brake calipers bolts from backing out.

The Sportsman has landed!!!  No more jig...but no wings yet...wait for it...

It's a wing!!  Done, inside & out, and ready to be put on the plane.  In the lower right of the picture you can see one of our fuel caps, which are flush to help the aerodynamics.  They were tough to put in--required Tracy to perfectly thread a gasket covered with gasket seal and not get any in the tank.

I unfortunately didn't get too many photos of the wings going up...you know, working.  Here Ryan and Ted are working on the left wing front pin, which was giving us a little trouble.  Each wing is held to the top of the roll cage with two large-diameter pins:

This is the forward pin in the right wing.  The light green is the wing spar coming in through the fuselage.

Same pin viewed from the back. 

This is the rear pin on the left wing.  Notice the pin is on a swivel assembly.  This is what enables our wings to fold back against the fuselage for storage if we need to.  Folding the wings will take about 10-15 minutes after the airplane is finished.

Tracy is putting the lower spar bolts in.  The tab on the middle bolt is for the folding wing option--it holds a rod which provides support for the wing during the fold.

Oh yeah--we hung the rudder today, too!

Between the vertical fin and the rudder you can make out the top hinge...

Here it is up close (not tightened yet).  Man, was that tough to get in there.

Halfway there--and our airplane looks like an airplane!!  Er, like a 4-wheel airplane.  Gotta get that tailwheel off for a short while.

Today was the last day of the airshow, so we had a lot of fun working.  This is a video i took on one of our breaks...just the random happenings outside the hangar!

Spotted at the airshow--I'm sure this is what my mom thought of when I told her we wanted to build an airplane.

The airshow was also a fly-in--airplanes & tents all over the place!  Gave us something to look forward to in the near future!

Okay, day 7 is on Monday.  I'll post a few pictures of our flying tomorrow.  Enjoy the rest of the weekend!  -zen

Day 5--Arlington Airshow, rudder & main gear install

Hello Everyone & Happy Friday!

First, some non-airplane building business--congratulations to the Bold Tigers for getting to resume flying ops!!  It's about time...wish i were flying with you guys but them's the breaks.  And, we've got a pretty good thing going on here...
...today was the Arlington Airshow, so I've included some pictures.  Our airplane work was light today to accommodate the show,  but we did get the rudder up on the tail and got the main gear legs fit.  Here we go...

Here's the rudder up on the tail section.  Matt and I are adjusting the stops to make sure the rudder deflection is even and to the right amount (25deg plus or minus 1deg).

In order to adjust the stops, we did some metalwork on a steel bracket attached to the bottom of the rudder.  As the rudder turns, the bracket swivels and hits the bulkhead--that's what governs the rudder travel.

Also on the tail, we drilled the holes that will eventually hold the tailwheel steering cables.  The oblong holes through the fuselage were fun to drill and required a pre-made jig to line up the placement correctly.  The hose that holds and protects the cable is held on with a fiberglass layup that we mixed up and sculpted.

This is the inside of the tailcone now.  The wire is temporary while the fiberglass dries--tomorrow or Monday we will insert the tailwheel steering cables there.

Our main gear is in now!  Note the big gap between the aerodynamic fairing on the gear leg and the fuselage.  That's on purpose--we will use these same legs when we are tailwheel-configured.  when the main gear moves forward in the tailwheel configuration, it will sit on a different part of the fuselage and be flush.

This is the view of the gear strut sitting inside the roll cage and secured.  The main gear is made of high-carbon steel and required a special drill bit to drill the hole.  We took our time--the clearance tolerance for the bolt is around 1/1000th of an inch, so the hole has to be perfect on this one.

Airshow day!  This picture isn't airshow-specific, but I thought it was funny.  The front plane is a Sportsman that is complete and flying, and will be painted and flown to OshKosh this summer.  The back plane is a DC-3 (also C-47).  We are told it was Ronald Reagan's transport when he was campaigning for Governor of California.  It has not flown or moved positions since 1995...so we see it every day here.

Kitplane owners band together & go places together.  These airplanes all flew in to the Glasair BBQ for various hellos.  In front is a Van's RV-10 belonging to Advanced Flight Systems, the company that makes our instrument panel.  I told the owner: "Nice RV-10!"  He said: "thanks...but my wife wants a Sportsman!"  The yellow bird is an RV-4A.  In back is a Piper Cub painted Army green.

We didn't make it over to the airshow side of the ramp, but still got a fine display.  You can see all the tents and booths across the runway.  Performing behind a Sportsman is a Yak-52.

Another airshow shot.  Good weather for it!

 

Our work area turned into a party at around 5 o'clock.  A lot of Glastar & Sportsman builders came in to say hello...some from as far as Canada.  It was funny to see so many people looking at our 4-day-old airplane just to see what the latest innovations are and how our build is going.  We are about to become part of a great little community.

That's it for today!  Tomorrow will be a slow work-day (only 2 Glasair employees and us) but we hope to have the wings up and maybe the landing gear ready to go anyway!  I'll still post our efforts to keep you updated.  Have a great weekend! -zen

Day 4--our 2-in-1 airplane, slick wings, & a battery

Hello everyone!

Today was a big day for the wings--the right wing is finished and ready for aileron and flap installment, and the left wing is right behind it with only about 3 hours of work left to go.

In addition, today we saw the nosewheel and tailwheel go on the aircraft.  That's right...we have a nosewheel and a tailwheel--say what?  Well, the Sportsman is a configurable airplane.  If built for it in the factory (which we are doing), the airplane can be easily converted from a tricycle-gear airplane to a taildragger in a couple of hours.  Configured as a tricycle gear, the airplane is statistically safer to land, maneuver on the ground, and train with in general.  As a taildragger, it is better for soft & short fields.  Our plan is to fly it initially as a tricycle gear to get accustomed--but the finished product will be a taildragger.

Right now it looks pretty funny, though--it's got a nosewheel, and a tailwheel--but no main gear at all yet.  We'll be there soon!!

Today I'm changing it up...we've spent so much time riveting the past couple of days I thought I'd share a little--here's a 20-second video of T"racy" the riveter in action on the left wing skins:

We left off yesterday with a wing having clamps all over it.  This is the finished product of the cove--at the very corner there you can see the 'doubler'--a thin metal strip in the glued-together sandwich.  Adding the extra layer of metal increases the strength where the cove skin meets the top skin.

Today I got to do the interior wing work on the left wing that Tracy did yesterday on the right wing.  This is a pneumatic pull-riveter in action waaaay down the aux fuel tank hollow.

This is the last time i hope to see the fuel tanks outside the wing...but if maintenance is required, they are removable.  It will take some rivet-drilling and time.  The primary tank is up close.  You can see the fuel lines (metal piping) in between the main and aux tanks.

Once the fuel tanks are in, then the lines go in.  This is one of two vent lines going into the primary tank.  The red cap in the upper right is where the fuel line (metal pipe) is about to go.  Putting these in required getting a forearm through the 4" inspection holes in the wing...tight.

These are the two vent lines coming out of the wing.  The vent system is simple but ingenious.  One line simply connects the aux and main tanks; this equalizes the pressure in the two wing tanks at all times.  The other line goes from the primary tank out the metal piping protruding from the bottom of the wing.  This keeps all venting to a single exit point (instead of one vent per tank).  The wing will eventually have a carbon fiber cap on it which will give the wing a clean aerodynamic finish, and also house our Navigation lights, Strobe lights, and Landing lights.  It will cover the vent tubing.  The electric wire for the lights is coiled up on the right of the picture by the leading edge.

We also finished the trim tab work on the horizontal stabilizer today:

This is the fist pic of our horizontal stabilizer.  Bryce is working on the trim tab. Matt is in the background working on our tailwheel.

Bryce ran the elevator trim motor with a 9-volt battery to test the travel limits.  we adjusted it to tech order travel with the jam nuts on the pushrod.

Last, here are a couple of shots of our weird gear configuration!

Here's the nose gear hanging on the airplane for the first time.  It is not steerable--you have to use differential braking to steer on the ground.

Tracy took this shot of me using a torque wrench to set all the bolts on the nose gear to the correct torque.  There are torque-specific bolts all over the plane.  Not enough torque and the bolt could back out.  Too much and it could shear the bolt.

Here is the tailwheel on the airplane.  Unfortunately, we didn't get to do any of the work on this.  Putting a tailwheel on the Sportsman requires some fairly detailed fiberglass work to beef up the tailcone structure (which is all carbon fiber).  The interior of the tailcone gets fiberglass layering on top of the carbon fiber, which adds strength and better flexibility.  Eventually there will be aluminum shims under the leaf springs you see here, helping the tailwheel conform to the fuselage shape and keep impact loads off the tail.

This is looking from above into the tailcone.  You can see the fiberglass layup at the bottom of the pic (tail end of plane).  At the top of the pic (bulkhead E), there's a massive nutplate with 8 bolts in it, all fiberglassed into the structure.

Here's a closeup of the nutplate.  Getting this to the exact right shape to be structurally significant is a challenge...I think that's why we haven't done it yet!

Okay, that's all 'til tomorrow.  It's possible that we might get the main landing gear in tomorrow--but it is Airshow day at Arlington so we'll see.  Happy Friday everyone!  -zen