John,

the yield  strength (Sigma) depends on the alloy. For 6082-T6 alloy Sigma=250MPa while for 6060-T6 alloy it is only 150MPa.

The 10” light poles
With the masts’ max diameter, D=10” (254mm) and the wall thickness is 0.312” (7.925mm) , and with the 6082-T6 alloy, the bending (yield) strength,

Mb=9300kpm.

That is, if I got my sums right.

If the mast is a 6060-T6 alloy, at 150MPa, the strength should drop to
MB=5600kpm

Now, if we roughly calculate the knock-down righting moment of your vessel, and guess the righting arm to be 1/5 of the beam, the righting moment should be

MR= Disp x Beam /5 = 23600kg x 4.32m /5 =20390kpm

In other words, the righting moment appears to be twice the bending strength of one mast (if 6082-T6 is used).

Samson’s mast
For comparison, if I compare with the ferro yacht Samson in Stavanger, at the same displacement, its solid pine main mast is 350mm diameter, which should give a max bending moment of

MB= 19000kpm,

even with a conservative strength factor Sigma =44.8MPa

To me it appears that your aluminium light poles are on the light side, but this is actually outside my area of experience, so I hesitate to draw a hard and fast conclusion.

Cheers, Arne

PS: By spreading the sail load on two masts, and taking a bit care, it may still work. The question is if the masts are stiff enough to avoid whipping around in a seaway. I don’t have a clue about that.