[ULF-1] Fw: ULF-1 weights

From: Member 9
Date: 2008-03-05 16:24 UTC
Message: #0105

----- Original Message ----- 
From: Member 9 
To: [email] 
Sent: Wednesday, March 05, 2008 4:11 PM
Subject: ULF-1 weights

Dear all,

let me add a few sentences to Member 27 remarks on empty weight: working with SPRUCE, 
an empty weight of 55 kg (excluding rescue system) can be achieved.
One half wing weighs 13,5 kg, the horizontal tail weighs 3,7 kg.

European builders, mostly using northern PINE (grown in northern Europe), come up with an empty 
mass of 60 to 62 kg due to the higher weigth per volume of pine Member 60 compared with spruce.

The maximum design gross mass is 155 kg, which leaves a sufficient amount of useful load to the airplane.

To facilitate getting into your project, I can only repeat my advice:

You should start building the horizontal tail first, because it shows basically all difficulties which you might encounter later on wing and fuselage. You learn to handle the material Member 60 without risking too much. If you are in doubt with anything you do or with anything you use, make tests to gain confidence. Do not hesitate to throw away a wasted part. Only if you follow the information given in the plans and manuals with respect to dimensions and quality of Member 60, you can expect that you stay in the weight limit. Generosity leads to overweight and reduces therefore the useful load. On the other hand please note, that there are only positive tolerances  (see also testing/checking instructions). 

Enjoy your project!
Best wishes for the year we are already in, and many happy landings.

Member 9