There are two skins behind cockpit and one in front of it. Our next step is get the two rear skins on before continuing on to the cockpit interior. The skins are fairly thick as skins go, and require a significant amount of curvature especially near the tail. This creates a lot of stress on the clecos when attaching the skins for match drilling because the skins would prefer to stay flat. The process of attaching the skins will be very familiar to the reader at this point: Match drill, debur, dimple, and rivet.
Before I could get to all of that I had to install the J-stringers at the top of the bulkheads. Fortunately, I had already fabricated these when we were doing the stringers for the lower fuselage. So it was just a matter of sliding them in place.
Match drilling
Debur
Well you get the idea. Here's Carolina working the cleco pliers...
All of this excitement was too much for our puppy.
Now the skins are dimpled and ready to go back on for the last time. It was about this time that I heard that now all too familiar sound effect of a record scratching in my head. I realize that I hadn't installed the static ports. If I don't to the static ports now I will have to crawl in the the tail cone do it later when it will be much more difficult. Ordinarily I am predisposed to doing things the hard way, but this time I think I'll take the easier path.
Static ports? What are static ports? I sense the readers unease as it would now appear likely that I am about to launch off in to another lengthy and oh so tedious discussion of airplane systems and/or history. Relax dear reader, this one will be brief:
The static port on an airplane is used to measure the local barometric pressure. This air pressure is then used by various aircraft instruments such as the altimeter and vertical speed indicator. The location of the static port is the most significant aspect of its installation. It needs to be in an area of relatively undisturbed air in order to get accurate pressure readings. In the RV's case, the static port is located on the fuselage side in between the wing and horizontal stabilizer. OK, now I suppose you're thinking, I see what it does and where it's located, but what is it? Well, that is simple. It's just a tube stuck out in to the wind. Perpendicular to the wind, actually. So as not to induce ram air pressure. The RV employs two static ports, one on each side of the fuselage which are connected together. Having two ports allows the instruments to see the average of the two for a more accurate reading.
The static ports were located on the fuselage's side according to the plans, but I'm using SafeAir brand ports which have a wide base which requires the port to be moved about .25" forward to clear the F-708 bulkhead.
Here is the back of the static port showing the wide flange and the interfering bulkhead.
The inside surface of the skin and the SafeAir static port flange are roughed up and then cleaned while Carol heads to the kitchen to whip up a batch of our favorite. Yes, it's time to get out the Proseal again.
The static port is bonded to the inside of the fuselage skin.
This is the Tee where the two ports come together.
And this is the static port from the outside. Not much to look at, really.
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