Sounds like Richard and I are on the same page. My 81 JM is also an original retractable light KR II. My instructions when I bought her 30 years ago was to fly the pattern at 80, over the fence at 60, touching down something below that. Works for me. Although I've tried three point landings, they don't feel good. I touch down on the mains somewhere around 50. Like Richard, 81 JM doesn't stall, she just sinks and mushes... I've always wondered about this.
On Mon, Jan 21, 2019, 6:51 PM Richard Seifert via KRnet < krnet@list.krnet.org wrote: > Hi Mark. > I have no first hand knowledge of a higher higher stall speed with the > newer airfoils and just repeted what was stated in one of the recent posts > on that subject. > I also just checked the info on my KR-2 plans which calls the stall at 42 > mph, and 52 mph for the KR-2S. I was never able to confirm either in ground > effect as i was too busy trying to end the float and keep it centered on > the runway. I did force stalls at altitude but felt they were not as > important as one that might unexpantly happen in slow flight. I tried slow > flight stalls and it simply went into an easly recoverable mush with an > airspeed of near zero! > I am sure stall speed is determined in a more scientific manner than mine > so i juust quote the plans value, and try to get it down below 70 over the > fence. > On the subject of retracts vs fixed gear, both have advantages and > dis-advantages. > I'm sure someone could come up with a list. I could list what i like and > don't like about retracts. > > On Mon, Jan 21, 2019, 4:02 PM Mark Langford via KRnet < > krnet@list.krnet.org > wrote: > > > Rich wrote: > > > > > The increased aircraft weight and the increased stall > > > speed / landing speed of the newer airfoils quickly overwhelms the KR > > > mechanical brakes leading to longer runway requirements. > > > > I'm not sure where you got the impression that the newer airfoils > > increase stall speed and landing speed. As I wrote yesterday, the most > > basic design point for the AS504x airfoils was that the stall speed > > remain the same as the RAF48. I don't know that we have any > > corroboration of that fact in real airplane form, apples to apples, > > except for Troy Petteway's plane. He flew with the RAF48 for quite a > > few hours, and then changed to the AS5046 after suffering wing damage in > > a forced highway landing. After talking to him immediately after his > > testing, my writeup from back then was "These improvements came with no > > penalty, as stall speed remained the same as before, with power off > > stall coming at 48 knots. The stall was gentle with no tendency to drop > > a wing." > > > > There's a lot more on this at http://www.krnet.org/as504x/ and the > > links from that page to other design information. > > > > It's worth noting that Troy's forced landing happened because he had no > > starter installed, and when the engine quit, he had no way to restart > > it. It happens. I mistook my mixture knob for the mixture knob and > > pulled the mixture out enough to stop the engine on climbout during > > crosswind (during my third flight), and the engine stopped immediately. > > Stuffing it back in and hitting the starter fired it right back up. > > > > Mark Langford > > m...@n56ml.com > > http://www.n56ml.com > > > > > > _______________________________________________ > > Search the KRnet Archives at > > https://www.mail-archive.com/krnet@list.krnet.org/. > > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to > change > > options. > > To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org > > > > On Jan 21, 2019 4:02 PM, "Mark Langford via KRnet" <krnet@list.krnet.org> > wrote: > > Rich wrote: > > > The increased aircraft weight and the increased stall > > speed / landing speed of the newer airfoils quickly overwhelms the KR > > mechanical brakes leading to longer runway requirements. > > I'm not sure where you got the impression that the newer airfoils > increase stall speed and landing speed. As I wrote yesterday, the most > basic design point for the AS504x airfoils was that the stall speed > remain the same as the RAF48. I don't know that we have any > corroboration of that fact in real airplane form, apples to apples, > except for Troy Petteway's plane. He flew with the RAF48 for quite a > few hours, and then changed to the AS5046 after suffering wing damage in > a forced highway landing. After talking to him immediately after his > testing, my writeup from back then was "These improvements came with no > penalty, as stall speed remained the same as before, with power off > stall coming at 48 knots. The stall was gentle with no tendency to drop > a wing." > > There's a lot more on this at http://www.krnet.org/as504x/ and the > links from that page to other design information. > > It's worth noting that Troy's forced landing happened because he had no > starter installed, and when the engine quit, he had no way to restart > it. It happens. I mistook my mixture knob for the mixture knob and > pulled the mixture out enough to stop the engine on climbout during > crosswind (during my third flight), and the engine stopped immediately. > Stuffing it back in and hitting the starter fired it right back up. > > Mark Langford > m...@n56ml.com > http://www.n56ml.com > > > _______________________________________________ > Search the KRnet Archives at > https://www.mail-archive.com/krnet@list.krnet.org/. > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options. > To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org > _______________________________________________ > Search the KRnet Archives at > https://www.mail-archive.com/krnet@list.krnet.org/. > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options. > To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org > _______________________________________________ Search the KRnet Archives at https://www.mail-archive.com/krnet@list.krnet.org/. Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options. To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org
