RE: new Arf Boomerang 14lb thrust
Guys
Now for the bad news! To achieve the suggested CG of 150 mm back from the leading edge I will have to add 1 1/2 lbs of lead to the nose, this is not good! Alternatively by my calculation a 25 % CG would be 187.5mm back from the LE . The root chord is 450mm the tip 250mm giving an average of 350mm at mid span 25% 0f this is 87.5mm plus the difference between the mean chord and LE is 100mm giving 187.5mm.
This can be achieved with only12oz of lead giving a dry weight of 14lb 8oz with a full hopper tank.
Would any one like to confirm my CG calculation before the model is flown? I cetainly feel that 150mm is too conservative if my calcs. are correct.
To be fair to Allan he suggests moving the CG rearwards after initial flights without giving a specific figure.
John Agnew