Overview of Chapter 21 - strakes and fuel tanks

The strakes and fuel tanks! So excited for this chapter! It's the "last" major structural chapter so after this one, I'll be able to focus on the finishing stages (engine, avionics, filling, priming, etc.)

The strakes are the "armpits" of the plane. Per plans, the strakes provide torsional stiffness and strength for the center-section spar, crew accessible stowage, two 25.5 gallon selectable fuel tanks with sumps, and also provide aerodynamic lift.

In this chapter, I will jig and build the strakes out of glass and type H45 foam, plumb vent lines, install fuel sumps (to provide fuel in unusual attitudes including sideslips, nose-down parking, and steep descents), and plumb fuel lines forward to a valve near the bottom instrument panel and back to the pumps and gascolator.

EPOXY NOTE: not all epoxies are fuel resistant! I will be using EZ-poxy 87 for ALL surfaces that will come in contact with fuel. Although I built my center-section spar with Aeropoxy (which is not fuel resistant), I will be covering the forward face of the spar with 1-ply BID using EZ-poxy to protect it. Kitplanes magazine did a fantastic job documenting a test to see which epoxy was most fuel resistant - click here to read the article.

The strakes are built with a few ribs and bulkheads. The rib templates are found on the full-size drawings (A14) and the bulkhead dimensions are found on pg 21-1.

 Without the bottom or top skins...


1. Passenger elbowroom mod

There's no debating that the Long-EZ is a small airplane, especially for the passenger - where leg room and shoulder/elbowroom is extremely scarce. New builders extend the passenger stowage access cutout farther aft (extending the BAB bulkhead with it), allowing the passenger to stick his/her elbows inside the stowage space - giving them the much more desired elbowroom they deserve! I'll explain this mod in more detail in future posts.

2. Jig table

Step 2 (on pg 21-3) has us build a jig table to install the bottom skin, ribs and bulkheads. While reading and prepping for this step, I couldn't see how one could properly align the ribs and bulkheads using this method. So I decided to glass the ribs and bulkheads on my workbench first, and then install them using a simple platform by shimming them precisely into place. Again, I'll explain my method in more detail in future posts.

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