Originally Posted by bigjohn
That's not tip stalling, that's directional instability. Large flat sided nose with a longer moment arm than the vertical tail surfaces. The large nose acts like a fin in front of the CG, pulling the nose of line and fighting the vertical tail.
Make the nose profile smaller or rounder or move the vertical tail farther back.
thanks i am proceding with the next model with a tractot engine which will push the cockpit/cabin back to have the vertical surfaces farther back.
the only problem though that OGE it shows no such instability. i tried in vain to upload the videos off my phone but no joy.
the rcpowers hydro does the something similar in the beginning of this video and at 2:44 but at the end where the swept portion of the wing is removed it displays no such tendency.
interestingly the single engined version which prob has a lighter wing loading does not drop the wing like the twin engine model.
i think being so close to the water causes the wing to stall due to the adverse press gradient.
the beriev 103 which was designed to take advantage of GE has slats which would most likely cure that problem. its wing is very close to the water as well.
i may be wrong but tip stall may be correct.