Installing the Firewall

If you are following along for your own Bearhawk build, here are a few items I learned while installing the firewall.

Raised Threshold, Gull Wing Doors & Piano Hinges

I've never been a fan of the Bearhawk's swing out door that conflicts with the wing strut.  When the lower portion of the door swings out, it hits the strut.  The workaround has always been what some call a "mouse door" at the bottom of the swing out to allow more door travel.  Personally, I think it just looks bad...  And functionally, it's just something you always have to be mindful of.  Passengers will always want to put their weight on the swing out when climbing in.  Who needs it?  I'm going to eliminate the swing out door completely.

Here's an example of a Bearhawk with a "mouse door" on the bottom of the swing out door:

Misc. Build Items

(Update 9-25-18 - Scroll down to the cable swaging section for a revision)

Ben and I returned from Oshkosh AirVenture 2018 last weekend.  It was a great trip and we came home with tons of ideas for the Bearhawk build.  Got to spend time with Mike Silvernagle, Canadian Bearhawk Distributor https://bearhawkcanada.ca  Always enjoy hanging out with Mike and talking Bearhawks!

Below are a few miscellaneous items I've worked on over the past month:

Unexpected Fix for Both Trim Tabs

Well, I didn't expect this one...  The trim tabs are both built into the elevators from the factory.  Before covering the elevators, the trim tabs need to be cut out.  Simple enough.  After covering the elevators, I also covered the trim tabs separately.  But, when reattaching the trim tabs to their respective positions on the elevators, I discovered a fitment conflict.

So, I it's time to remove the covering and perform some surgery

Transition from trim actuator tube to the trim tab push rod

This is pretty straight forward but I was not able to find any examples on the Bearhawk builders forum or in the plans.  At the bottom of both horizontal stabilizers the trim tab push rod connects to the actuator tube that runs through the ribs of the H Stab.  I wanted to make a hole big enough for access for maintenance/inspection.  I was hoping for a cover with a slit that the tab on the actuator tube could poke through.  But the nut and bolt sit right on the fabric line so the hole is larger than I intended.  I suppose I could have extended the tab to avoid the conflict with the nut and bolt, but I can do that after the bird is flying.  The last pictures show what I am talking about.

Where the push rod and actuator tube connect is where opening will be

Balancing the Elevator

The elevator and ailerons are generally required to be balanced to improve stick feel, longitudinal stability and reduce the potential for control surface flutter while in flight.  The Bearhawk is no different.  The method I chose to use to balance my elevator differs slightly from the Bearhawk plans.  The plans show clamping plywood to the leading edges of the elevator then pouring molten lead into a form, as shown here...

Learning Fabric Covering using Stewart Systems

Over the past week I installed the cabin floors, rudder pedals/brake master cylinders and the control stick assembly.  I had a slight problem with the control stick assembly binding after attaching it to the floor tabs.  After several on-off installations, I removed a slight amount of material around the torque tube, lubed it up real good, and now it moves free and correct without any binding.  Very smooth!

I could and will do more on the fuselage soon, but what really has my interest is the fabric covering process and I am challenged to learn as much as I can about how to do it and what is the best system to use.  This will be my first time covering an airplane so I have been excited to "figure it out"!

How I built the Rotisserie

Several have asked how I built the rotisserie.  Here's a video:

The Rotisserie WORKS!

The kit arrived today!  Mike Nellis was the delivery driver and did a great job unpacking and helping me unload the trailer.  It's amazing how well packaged the kit is.  Almost impossible to get damaged while being shipped.

We put the fuselage in the garage and the wings went down the street to a storage unit.  When Mike left, I went back to the garage and mounted the fuselage on the rotisserie and it worked great!  Watch the video. 

Preparing for the delivery of the Bearhawk kit

Friday June 1, 2018

Today is the big day!  Delivery of the Bearhawk 4 Place kit will happen this afternoon.  Last evening I finished setting up the long skinny two car garage for its new occupant.  I also completed the fabrication of the fuselage rotisserie and feel pretty good that I built it right.  It will need some fine tuning and I will get exact measurements when the frame arrives to mount the tail section and firewall, but that shouldn’t take very long.  So once the fuselage is mounted to the rotisserie, the building begins!