- Hi everybody,
i read about addded fuel tanks for cricri. I would prefer to install
further fuel tanks to the wing tips. The volume of the original Wing
tips is approximate 3,5 litre per side. At this solution you do not
change the centre of gravity with full or empty tip tanks - most
important for such a small aircraft. You don't increase the masses of
those aircraft parts, which does'nt contribute to the lift. The bending
moment of the wing spar at the wing root is smaller.
If you decide to install a bigger fuel tank in to the fuselage, the
bending moment at the wing spar will increase. The fatigue life is
I decided to design my wing tips as optional fuel tanks. Because of
wing geometry the tips are higher than the bootum of the main fuel tank.
So the gravitation will lead the fuel to the main tank. You just need to
make a little hole through the ribs for a fuel tube. I'm not sure about
the dynamic behavior. I just know, that a added mass at the end of the
wing reduce the own frequency. If the weight of wing tip tanks ist to
height wing flutter could be possible. I will ask a specialist.