Thanks Mike! That's a hack of nice idea to deal with the sensitive CG issues for experimental & light aircraft such as ours, and I was actually thinking of adapting the same kind of "adjustable CG" design tricks along the same direction.....
Well, there is obviously neither bombproof mechanism to guarantee 100% reliability to move the flexible weight at the right spot & right timing, nor devices that will remind you every time prior to take off without incurring big cost increase with complex electronic warning system to be added. May be there is a better way to stretch out the CG envelope just a bit more without modifying the fuselage or increase the HP of the powerplant, perhaps? Another rudimentary solution might be just to install one or two two-gallon water tank to be placed where to make the CG just a bit tail heavy, and the pilot could easily pull open the valve to dump the water quickly as needed. A 2nd weight-balancing water bottle could be installed in the front to make quick CG adjustment through dumping or pumping water back & forth.... This could help stretching up the CG tolerance practically and cheaply, right?! Stay and fly safely! Dr. Hsu On Thu, May 13, 2021, 7:01 AM Mike T <mctagli...@gmail.com> wrote: > I saw one KR-2 design where the owner built the plane with a small weight > in the tail cone, designed to be easily moved forward as needed. As long as > you had a bombproof method of attaching it (and an idiot-proof way to > remind you where it was), this could be very useful. > > Mike Taglieri > > On Thu, May 13, 2021, 12:40 AM Dr. Feng Hsu <fenghs...@gmail.com> wrote: > >> Thanks Mike for your invaluable input on the CG issues when two people are >> in the KR2 cockpit for training.... I believe it is much easier to resolve >> the tail-heavy CG issue rather than dealing with the inherently narrow CG >> envelope issue from the standard KR2 design, correct? I am wondering if >> there is any quick & easy solution to check on CG balance or adequacy >> after >> people & stuffs and fuel are loaded prior to heading to the runways?! >> >> Safety is always #1 priority! >> >> Dr. Hsu >> >> >> On Mon, May 10, 2021, 4:05 AM MS <propbala...@att.net> wrote: >> >> > I very much agree with the idea of not stuffing two people in a KR for >> > training purposes. My previous standard KR was WAY out of CG with just >> two >> > normal-sized people in it and my KR wasn't badly built - an engineer >> with >> > McDonnell Douglas built it - built three of them in fact - and had the >> > added weight of the Maloof prop out front but was still very tail heavy >> > with two people. Most early KR's tended to go tail heavy with two >> people. >> > Trying to develop familiarity with a plane that has such a tendency >> toward >> > aft CG doesn't sound like a good idea. Not to mention, two people each >> > with heads canted toward the center because the canopy had such poor >> > headroom made for an unpleasant ride for both pilot and passenger, quite >> > aside from trying to do any flight familiarization. >> > >> > With the many improvements that have been made to the standard design - >> > wider cockpits, longer fuselages, problems the original design had with >> two >> > up have been eliminated of course but still . . . with two people and >> > marginal horsepower seems asking for trouble. It's never been a >> two-place >> > plane . . . really. It's a very cool one person plane. Long runway to >> > eliminate concern of running off the end, either with an abort or with a >> > long landing, plus no controller distracting things . . . if a person >> has >> > any skill at all at flying, the KR is not quirky or difficult. 90% of >> > newbie problems are simply from trying to touch down while the plane >> still >> > wants to fly. That ends up with bent nosewheel struts and broken props >> . . >> > . happens all the time, not just with KR's. Speed control is so >> important >> > and finding that comfortable spot with a new plane is always a bit >> > nervewracking. It takes a lot of self-discipline those first few >> flights >> > while getting a feel for where the approach speed should be. This isn't >> > just with KR's. I think everyone, flying a new plane for the first >> time, >> > has a hard time keeping their approach speed down. >> > >> > Slow flight with a few stalls is a great thing to do on that first >> > flight. Neither of my KR's did anything in the stall except mush. >> It's a >> > gentle wing (if built correctly and nothing is out of whack) with no bad >> > habits. Generations of KR builders/flyers have gone through this and >> > gained the benefit of true stick and rudder skills with this forgiving >> > airplane. There's no need to treat the KR like it requires some special >> > training. It's about as honest an airplane as any of us will ever fly. >> > Just slow down before the wheels. If you have to wait for it to slow >> down, >> > just wait. That's exactly the reason to use an extra long runway while >> in >> > the familiarization phase. >> > >> > Putting two people in a KR for training purposes seems a recipe for an >> > unpleasant experience . . . although, come to think of it. >> familiarization >> > flying with Jim Morehead was not uncomfortable at all . . . so I'm all >> > wet. Depends on the plane I guess. Jim's tri-gear plane was just as >> > comfortable with the two of us in it as a Piper Cherokee 140. >> > I sure had some unpleasant experiences with my first (standard design) >> KR >> > when I had another person in the cockpit though. With such an aft CG, >> if >> > one doesn't die first, one learns to become a pretty good pilot. >> > >> > MikeKSEE >> > ________________________________ >> > -Please see LIST RULES and KRnet info at http://www.krnet.org/info.html >> > -Change list delivery options at >> > https://list.krnet.org/list/krnet.list.krnet.org/ Affinity List Info >> Board >> > -Search recent KRnet Archives at >> > https://list.krnet.org/empathy/list/krnet.list.krnet.org/ >> > -Search < >> https://list.krnet.org/empathy/list/krnet.list.krnet.org/-Search> >> > John Boyea's decades of archive at >> > https://www.mail-archive.com/krnet@list.krnet.org/ >> ________________________________ >> -Please see LIST RULES and KRnet info at http://www.krnet.org/info.html >> -Change list delivery options at >> https://list.krnet.org/list/krnet.list.krnet.org/ Affinity List Info >> Board >> -Search recent KRnet Archives at >> https://list.krnet.org/empathy/list/krnet.list.krnet.org/ >> -Search >> <https://list.krnet.org/empathy/list/krnet.list.krnet.org/-Search> John >> Bouyea's decades of archive at >> https://www.mail-archive.com/krnet@list.krnet.org/ >> > ________________________________ -Please see LIST RULES and KRnet info at http://www.krnet.org/info.html -Change list delivery options at https://list.krnet.org/list/krnet.list.krnet.org/ Affinity List Info Board -Search recent KRnet Archives at https://list.krnet.org/empathy/list/krnet.list.krnet.org/ -Search John Bouyea's decades of archive at https://www.mail-archive.com/krnet@list.krnet.org/
