KR> KR1B motorglider criteria question
I can't argue with that...I was just wagging it because wiki says 34 lbs. Still, a very good looking selection for the purpose. I think I have figured why the faa has that criteria. I think they are combining surface loading and aspect ratio...both use wing surface...just a guess.of course...but it would be max gross in that case. https://sites.google.com/site/mykr2stretch/ https://sites.google.com/site/mykr2stretch/parts-for-sale
KR> KR1B motorglider criteria question
The KFM engine weighs more than 40#. That is the bare engine which won't run without the complete exhaust system installed.. Only put out 25hp for under 3 minutes and then dropped off to about 18hp in cruise at 5900 rpm. Ron On Mon, 7/11/16, jon kimmel via KRnet wrote: Subject: Re: KR> KR1B motorglider criteria question To: "KRnet" Cc: "jon kimmel" Date: Monday, July 11, 2016, 8:11 PM The goal with a self launched sailplane is glideslope and low stall speed...so high aspect ratio and low weight.? The engine we selected back in '82 was a kfm 107...25 hp at 40 lbs.? You could do a max gross of under 500 lbs with an engine like that. https://sites.google.com/site/mykr2stretch/ https://sites.google.com/site/mykr2stretch/parts-for-sale ___ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
KR> KR1B motorglider criteria question
The goal with a self launched sailplane is glideslope and low stall speed...so high aspect ratio and low weight. The engine we selected back in '82 was a kfm 107...25 hp at 40 lbs. You could do a max gross of under 500 lbs with an engine like that. https://sites.google.com/site/mykr2stretch/ https://sites.google.com/site/mykr2stretch/parts-for-sale
KR> KR1B motorglider criteria question
It will weigh 800 lbs if you put a Lycoming O-720 on it. John In a message dated 7/11/2016 3:48:08 P.M. Mountain Daylight Time, krnet at list.krnet.org writes: At 03:33 PM 7/11/2016, you wrote: >if gross weight of say, 800lbs, what would the span need to be? ++ I calculate 36 feet span but I can't imagine a kr1 motor glider having a gross weight of 800 pounds I doubt the spars will handle a 36 foot span. 36 X 36 = 1290 sq ft X .62 = 799.8 pounds Then again, I'm not an engineer. So , what is the span of a KR1 motor glider?? That will give the real numbers, not a guess. Larry Flesner ___ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
KR> KR1B motorglider criteria question
The KR-1B wingspan is 27', empty weight 484 pounds, and gross weight 800 pounds. According to the previously mentioned rules (assuming they are true), that means a max weight of 452 pounds, whether gross or empty, which is less than either of the advertised numbers. Mark Langford ML at N56ML.com http://www.n56ml.com
KR> KR1B motorglider criteria question
At 03:33 PM 7/11/2016, you wrote: >if gross weight of say, 800lbs, what would the span need to be? ++ I calculate 36 feet span but I can't imagine a kr1 motor glider having a gross weight of 800 pounds I doubt the spars will handle a 36 foot span. 36 X 36 = 1290 sq ft X .62 = 799.8 pounds Then again, I'm not an engineer. So , what is the span of a KR1 motor glider?? That will give the real numbers, not a guess. Larry Flesner
KR> KR1B motorglider criteria question
if gross weight of say, 800lbs, what would the span need to be? Sent from my T-Mobile 4G LTE Device
KR> KR1B motorglider criteria question
My assumption is that they are talking gross weight. We did a powered sailplane design as my senior design project in college...but I don't remember any details...long long time ago...found a great little 2 cylinder engine that weighed next to nothing. https://sites.google.com/site/mykr2stretch/ https://sites.google.com/site/mykr2stretch/parts-for-sale
KR> KR1B motorglider criteria question
At 08:30 AM 7/11/2016, you wrote: >At 07:59 AM 7/11/2016, you wrote: > >>"The maximum weight to wing span squared w/b squared ) does not exceed >>>3.0 kg/ma (0.62 lb./ft squared )" >>> >>>http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_21.17-2A.pdf >>+++ >After further thought, an easier way to figure; ( If my high school >math is correct) >Square the wing span and multiply by .62 = lb/sq ft +++ I'm ASSUMING we're talking empty weight. I didn't read the reg that close. Actual numbers to be determined by the builder. ( my disclaimer) Larry Flesner
KR> KR1B motorglider criteria question
At 07:59 AM 7/11/2016, you wrote: >"The maximum weight to wing span squared w/b squared ) does not exceed >>3.0 kg/ma (0.62 lb./ft squared )" >> >>http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_21.17-2A.pdf >+++ After further thought, an easier way to figure; ( If my high school math is correct) Square the wing span and multiply by .62 = lb/sq ft example: 27 ft. span = 729 sq ft X .62 = 451.98 lb sq ft ( max weight) Larry Flesner flesner at frontier.com
KR> KR1B motorglider criteria question
"The maximum weight to wing span squared w/b squared ) does not exceed >3.0 kg/ma (0.62 lb./ft squared )" > >http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_21.17-2A.pdf +++ Chris, I checked the web site and couldn't find info on the KR1-B wing span. Here is the way I read the formula: For sake of example let's say the wing span is 27 feet and the airplane weighs 450 pounds. 27 X 27 = 729 square feet. 450 pounds / 729 square feet = .617 lb/sq ft. That just meets the requirements.\ You would need the actual numbers to use as a building target , i.e, weight to wingspan. Larry Flesner
