Kevlar is also not a good idea because it has very low compressive
properties, which is exactly the sort of loading you'll get in an arch over
the cockpit in a Europa bouncing on its head.
Carbon, although more brittle, is much better in this respect. Witness the
Formula 1 crashes, where the tub in which the driver sits is all carbon. If
you can afford it use the High Elongation types of fibre such as Toray T700
or even the intermediate modulus fibres with highb elongaions such as T800,
rather than the standard carbon fibres such as T300 types.
Ideally, though, land the aircraft the right-side up.
David
-----Original Message-----
From: owner-europa@aztec.houxou.com
Subject: Re: Inverted Drop Test
Nic wrote:
>
> Has the XS been tested for some kind of rollover protection standard?
Ah.... yes (in several crashes) - and found wanting: In the examples I have
seen, the
cockpit area remains pretty intact (even in severe crashes) but the arch aft
of the
windscreen collapses.
> Have there been any upgrading in the fleet?
>
> It seems like a nice Kevlar rope inlay over the windscreen arch, supported
> aft by the roof board.
> Perhaps another arch aft at the spar up to the roof board.
We plan to deal with it by laying in some tows of carbon uni approx from
seat front
outer corner to seat front outer corner over the whole arch, then bonding a
5mm thick
filler to the forward face of the door flange (tapered to nothing below
where the door
flange goes horizontal) followed by more carbon - so the end result is a zZ
box (if you
see what I mean)
Don't think that a kevlar rope inlay will do anything - you need uni fibres
running
laterally to deal with the loads...
M
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