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Message-ID: <007101c5580d$0efe4090$e21decdc@george>
From: "George Lendich" <lendich@optusnet.com.au>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
References: <list-942518@logan.com>
Subject: Re: [FlyRotary] Re: Aluminum side housings
Date: Sat, 14 May 2005 08:42:35 +1000
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> George Lendich wrote:
>
> >>We were discussing aluminum side and intermediate housings a couple of
> >>weeks ago.  A figure of somewhere around 15lbs per housing in weight
> >>savings was thrown out.  The exact figure isn't as important the fact
> >>that several Delta builders have had to stack approximately that much
> >>weight in the tail to get the proper W&B.
> >>
> >Ernest,
> >Surface treatments are problematic- no real cost effective treatment as
yet.
> >Composite( aluminium and steel) housings don't save that much weight, I
> >forget the exact figures but will save about 30 lbs, at best. A hell of a
> >lot of work ( and cost) to get that 30 lbs.
> >
> >
> >
>
> I tend to agree with you, George, but you have to balance the work
> required to remove 30lbs from the engine against the work required to
> remove 30lbs from my slim figure*.  I won't even consider aluminum sides
> until I do a (semi) final weight and balance.  If it comes down to
> aluminum housings or more junk-n-da-trunk, the debate will be wide open
> again.
>
> (The humor will be apparent when you get to the email where Ed tells me
> that I'm a little stout for his RV 8*)

Ernest,
Don't get me wrong I'm actually working on aluminium housings as we speak -
however the truth of the exercise is fully evident when costs and weights
are real, rather than anticipated. Machining anything is a hugely expensive
part of any development and there's a lot of machining in end housings.

Hey I'm on the diet too, but firewall forward weight is my main concern, for
C of G requirements.
George ( down under)