How structural are the baggage bulkheads?
 

Most of us, I suppose, are tired of unscrewing and re-screwing all those stupid screws on the two piece baggage bulkhead at condition inspection time -- especially if you're old and stiff and the hangar is hot in the middle of the summer. One "solution" is a one piece honeycomb bulkhead that would be stiff enough that only a few screws would be required to hold it in place.

The question, though, is how structural is the existing bulkhead? No surprise, Van's says that it is structural, end of discussion, but my eyeball engineering doesn't get it. Seems to me that with the horizontal creases in the aluminum, those bulkheads wouldn't carry any vertical loads. Similarly, it would seem that those bulkheads would only carry lateral tension loads, not compression loads. And there is the T shaped structure immediately behind the bulkhead...

Yes, we all have opinions on this, but do any structural engineers have observations on the topic? Please, no pontifications on what to do and what not to do.

A primary function of bulkheads like those is to carry shear that develops when the fuselage is twisted. Thus they are structurally important for torsional stiffness.

The standard Van's Aircraft position is that the baggage bulkhead panel is structural on all models and should be installed, with all fasteners, for flight.

So I talked to a knowledgeable friend not on VAF...

He relates an RV that flew, poorly, with the baggage bulkhead removed. And an RV-8 that had obvious torsional inadequacy with a forward fuselage bulkhead removed.

I don't understand either of these phenomena, but I'm looking forward (sort of) to many more sessions of screwing and unscrewing...

One thing that helps access is that the right side control stick is easily removable.

Think about it this way: how flimsy would a beer can be if you cut the end out of it.

The question I have, Scott - is the corrugated version critical? For those that want to install air conditioning, it would be great to have a flat sheet there so that you dont have as much air be pulled through the tailcone.

Since the baggage area cover fastens onto a bulkhead which is essentially a circular C channel, I don't understand how this point is relevant. The bulkhead already has a bunch of metal to help it maintain its shape.

What effect would having a baggage tube opening (like some other aircraft) have on the panel?

The tube would be for things like pillows and sleeping bags that are light but voluminous..........

EZ
 

1-Cordless screw driver
2- change your Annual CI to March or April when weather is cooler and flying limited.

It seems like a one piece honeycomb bulkhead would provide adequate torsional stiffness, similar to the designed panel with horizontal stiffener bends, but those loads are carried through the circular fuselage bulkheads via all those screws. It you want to replace the light weight bent bulkhead panel, you still need all those screws to carry that load that is fractionately shared by each screw. Maybe that’s why they are #8 vs #6. Just my guess - I’m no Steve Smith.