A TALE OF TWO SECTIONS...
Posted: 06 Jul 2019, 20:38
In all the years I have been towed up by Greenley tugs, I have never seen one stall out and spin... Conversely, the 75% electric Greenley that Motley & I have built has a stall behaviour that's hairier than a Bigfoot's armpit. (Any stall under 150' and it's goodnight Vienna) You might opt for the most obvious reason: the bigger Greenley pilots know what they are doing!
It got so bad in the end that Smallpiece and I made Motley do all the towing, although I believe he's out of therapy now. Our version, although the construction methods have changed, is to all intents and purposes, the same as the original, with the same symmetrical section.
Last week I designed and built a new wing, using the tried & tested glider section HQ35, thickened to 17% to match the original design. (No washout of course) The reason? the section's tried & tested low speed behaviour.
Yesterday we tested the new wing and the results couldn't have been better. Now the model needs written permission before it will stall, and recovery is immediate. I have fitted full length flapperons, which are mixed to come up together as a landing aid, as per glider experience.
I mention this for anyone who might be designing a similar tug or sports model and would like a reasonable guarantee of good low speed behaviour.
It got so bad in the end that Smallpiece and I made Motley do all the towing, although I believe he's out of therapy now. Our version, although the construction methods have changed, is to all intents and purposes, the same as the original, with the same symmetrical section.
Last week I designed and built a new wing, using the tried & tested glider section HQ35, thickened to 17% to match the original design. (No washout of course) The reason? the section's tried & tested low speed behaviour.
Yesterday we tested the new wing and the results couldn't have been better. Now the model needs written permission before it will stall, and recovery is immediate. I have fitted full length flapperons, which are mixed to come up together as a landing aid, as per glider experience.
I mention this for anyone who might be designing a similar tug or sports model and would like a reasonable guarantee of good low speed behaviour.