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

Day 3--Left Wing Finishing, Motor mount, & surprises!

Hello Everyone!
By the Two Weeks to Taxi timeline, we are now 25% of the way to our first taxi and about two weeks from the first flight of our airplane!!  After today, we are actually a couple of hours behind, but nothing we can't make up.  Today was again filled with new experiences (trend item!) as we finished the left wing and mounted the engine to the fuselage.  In addition, while we were working some things magically 'appeared' on the airplane...we had to scurry to find the folks who put them in so we could see how things are done.  Here's the wrap-up!

First, here's the progress on the left and right wings:

This morning we put the right wing up in the rivet room next to the nearly-riveted left wing.  Immediately after this photo Ryan put the upper skin surfaces on the right wing and prepped them for riveting.

This is an example of my sometimes not-so-Zen-like qualities...didn't put full pressure on the rivet head prior to depressing the trigger.  The rivet bucked in the back but obviously isn't flush in the front.  This hole had to get the bad rivet drilled out and a new one put in.  For the record, Tracy's current pneumatic rivet score is 100%...no errors.  I married up.

Left wing right before it came off the jig--skin rivets complete!  I didn't count them.  There are a lot.

This picture clearly shows the different between flush rivets (top) and universal head rivets (the nubby ones below).  In this case the flush rivets are for aerodynamics over the leading edge of the wing.  The black circles are rivet holes that were filled with clecos until the final riveting.

Once off the jig, the next step is to put the "cove skins" on the wing.  The "cove" is at the trailing edge of the wing and it's where the flap fits (inboard) and the aileron fits (outboard).  If you look at the curve of the metal, it looks like it seats the leading edge of another wing--which it does, sort of.  Our flaps and ailerons are each shaped like small wings of their own.  When retracted they fit into the coves with minimal clearance, helping the airflow over the wing.

One of the interesting things about securing the Cove skins: they're actually glued to the top wing skins, not riveted.  The glue is Loctite epoxy, which is nasty stuff (hence the gloves and respirator) but should seal the trailing edge from moisture.  Check out all the clamps--only 1/4" gap between them to ensure a tight seal.  The epoxy takes about 3 hours to dry...so we will remove the clamps tomorrow.

I missed a picture of the fuel tank going in, but hope to get it on the Right wing.  In this picture the fuel tank is already in with the fuel lines run, and Tracy has almost finished riveting in the wing root rib.  The cylinder in the middle of the tank is the electronic fuel gauge--you can see the grounding wire coming out of it.  The fuel from this tank (the primary tank) comes out of the lower-most, silver-dollar shaped hole.  It's gravity feed so the airplane doesn't depend on electronic systems to get fuel to the motor.  Genius.

On the contrary, fuel from the outer wing tank (the auxiliary tank) has to get from the outboard of the wing through fuel lines to the main tank.  It does this with an electric fuel pump (above), which Ryan put in today along with the fuel lines.

Today was also Engine mounting day!  There's a lot of small but time-consuming work to be done on the engine during the mounting process:

First, the engine mount!  This is one of the first things Tracy did this morning.  Note the four big holes on the front end--these are the mounting points.  Unlike a car, you don't mount an airplane engine from all the way 'round--only the one side.  Therefore, the mounting points are reinforced and the engine/prop balance has to be perfect.  Those tight tolerances are one of the driving factors for aircraft engine price.

I caught Matt studying the manual for our motor--good on 'im.  With most of the work we're doing, the techs have the steps memorized, so they don't reference a checklist during a step--only at the end of the step, to make sure they didn't miss anything.  In this case, Matt is being more deliberate because of the various motor types to go on the Sportsman.  He is 'de-pickling' the engine and getting it ready for Sportsman-specific applications.

One of the Sportsman-specific applications is this gold-colored heat shroud that Tracy put over the main fuel pump this morning.  In some aircraft the airflow inside the engine cowling might be enough to keep the fuel pump cool--apparently not so in the Sportsman.

Check out the detail in the safety wire.  Today we learned that when safety wiring, you have to check: direction of twist, number of twists per inch (varies by application) and bend direction.  Note that if anything pulls on the safety wire, it will pull in a clockwise direction--tightening the bolt.  Ben demo'd this safety wire and it took him a good 10 minutes to put it in.

Mom, you asked how to get an engine on an airplane--here's your answer!  The engine weighs around 400 pounds.  No way we're going to lift it without hoist power.

Here's a picture of the engine (gold) on the mount (grey) with the massive shock-absorbing bushings (black) on both sides of the mount.  The bushings look almost the same but are not.  The right one is a "compression bushing" which is designed to dampen the compression forces as the motor pulls on the bolt head/washer.  The bushing between the mount and motor is a "tension bushing" which handles different vibrations as the motor tries to pull away from the mount.  On the bottom of the mount, the order of the bushings is reversed (because the order of the motor's push-pull effect is reversed).

This is my exact view to the lower-left engine bolt.  The working space in here is pretty tight.  It took Matt & me about 45 minutes to get all 4 cotter pins into the 4 bolts with the correct bend & cut length on the pins.  That's longer than it took to mount the engine. 

Finally, here are some of the random additions we either worked on or had to just keep up with today!

I caught Bryce putting a radio antenna into the tail.

Here's the radio antenna from the top of the tail, right before Bryce caps it.  Since our fuselage is carbon fiber, all of our antennas have to be external.  If they were internal or contacted the carbon fiber, the signals would get distorted since carbon fiber conducts electricity.  In this case, the exterior antenna (coat-hanger-lookin' thingie) goes through the rectangular cutout through non-conductive fiberglass glue to the antenna.  the antenna cable runs down the rudder and forward through the fuselage to the avionics panel.

Another thing Tracy worked on today is the control yoke.  Our aircraft has center sticks, not a traditional yoke--but the sticks are connected mechanically by this bar, which is still called a control yoke.  So if one stick moves--they both move.

Three pulleys: Left Flap, Right Flap, and aileron (remember the aileron crossover cable from yesterday?  That's why there's only one, i think.  I'll make sure tomorrow).  One thing is certain--these are right between and directly under the front seats (between the two control sticks).

The springs on the rudder cables (up by the firewall) are centering springs--to pull the rudder (or the tailwheel in taxi operations) back to neutral after a rudder push.

This is our future rear seating/cargo area.  The entire fuselage from the first bulkhead all the way to the tail will be empty to keep the plane within center-of-gravity tolerances.

Whew!  That's a lot.  Y'all gotta let me know when this gets boring. 
On another note--the Arlington fly-in and airshow is this Friday.  In this part of the country there are a lot of vintage and unique aircraft--we saw some of them flying in today.  We should get a small break on Friday and I'll try to post some photos of the happenings around the airfield here!

See you tomorrow! -zen