Chapter 23 – Course Deviation

Ok, folks . . . time for a chat. No pics.

After a lot of thought, research and assessing what we would call in military planning as COAs, or courses of actions, today I came to the hard realization that I need to install the lower engine cowling.

The reason why I had decided not to go with my original plan to install the lower engine cowling when the bird was flipped upside down was in part what the plans stated, what other builders had done, and what conventional wisdom pointed to . . . and that was that the cowling should be installed with the engine mounted in place.  Makes total sense.

But at this juncture I find myself in the “what comes first?” or proverbial chicken-vs-egg argument.

I don’t feel right in proceeding with the glassing of the lower aft fuselage/Hell Hole with an unquantified variable out there: the bottom cowling interface.  To go back and have to do rework of the lower aft fuselage once the plane is back upright, defeats the true purpose of doing it now while the fuselage is inverted.

If I am to define my problem, the two antagonists are 1) the lower aft fuselage needing to be reworked once the plane is upright and the bottom cowl gets installed, or 2) the bottom cowling isn’t aligned perfectly with the engine, specifically the flywheel and prop spinner flow guide.

Antagonist #1 could end up being a royal PITA to have to deal with later, once the fuselage is back upright, and could very well actually be a big frustration in getting the bottom cowling mounted.

Antagonist #2 seems the least sinister of the two.  If I align the bottom cowling centered on the fuselage centerline, then how far off do I really expect my engine to be one way or the other?  Not much at all.  And I do have the ability, although not desirable, to trim away or rework the bottom cowl once the plane is flipped back upright.  Even at that point the bottom cowl install would be virtually completed, as well as the bottom aft fuselage/Hell Hole, bottom fuselage-to-bottom cowling interface, and the RAM air scoop install… all dialed in to each other with good tolerances.

Thus, at this point I see no other option than to focus my immediate efforts on getting the lower engine cowling installed as I also press forward with the final configuration of the aft bottom fuselage/Hell Hole completion.

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