Larry H
> On Apr 11, 2019, at 10:33 PM, Jeff Scott via KRnet <krnet@list.krnet.org>
> wrote:
>
> Mike's answer here is the first to really hint at the solution for speed.
> Horsepower is great for climb, but if you want to go fast, work on drag
> reduction. If you want to go even faster, work on weight reduction. When I
> first finished my KR, I was pretty disappointed in the performance. I
> couldn't even keep up with a Cherokee 235, and had to struggle to outrun a
> Cherokee 180. I've put a lot study, time, and effort into drag reduction on
> my KR. Today, my KR is 80# heavier and roughly 40 mph faster than it was
> when I first flew it 22 years ago, and I find that I can usually outrun the
> Mooneys and SR-20 Cirrus guys. A 40 mph improvement is not an insignificant
> number. Additionally, reduced drag also requires less HP for level flight
> resulting in more excess HP, which equals better climb performance.
>
> Drag reduction takes work. What I found over the years is that every little
> bit helps. Keep at it and pretty soon all those little things that make you
> 2 or 3 mph start adding up and you suddenly find your plane is will exceed
> your expectations.
>
> With every round of drag reduction I have done on my plane, I come away with
> more ideas for how to continue to improve it. I have more ideas in mind now.
> I'm just not sure I still have the ambition to execute them.
>
> Longer wings won't necessarily make the plane fly slower. Flat plate drag
> will go up marginally, but the induced drag of the airfoil may drop off
> significantly. In fact, the longer wing may significantly increase the
> cruise speed depending on the altitude and load. However, when you start
> lengthening the wings, now you need to re-evaluate the wing structure for the
> additional leverage caused by the longer wing.
>
> The KR you guys are remembering from Red Oak was a KR-360, which had a 180 HP
> IO-360 mounted to the nose. But the only real resemblance that plane had to
> a KR is that it also had a wooden airframe and spars. The fabrication was
> creative and the workmanship was really nice. But we haven't heard from him
> since.
>
> I can only think of one KR that had an O-320 mounted up front. It was
> destroyed on it's second flight with the larger engine, even though the pilot
> was an experienced builder and KR Pilot. I know the problem was not CG
> related as his O-320 weighed in exactly the same as the O-235 he was
> replacing.
>
> I can't opin whether the structural capabilities have reached the end of it's
> capabilities or not, or that an O-320 won't be a fine engine on a KR as I
> don't have the engineering background to do the calculations. But do keep in
> mind the intended VNE of the plane, which can be easily exceeded with an
> O-200 or Corvair, and how much weight we are putting on these airframes that
> were originally designed to fly with VWs. At some point in time, we will
> start to push the margins of safety if we haven't already done so. 22 years
> ago when I showed up at the KR Gathering with my new Continental powered,
> "stretched" KR, the old guard was convinced that my plane already exceeded
> what the plane was intended to be, and were pretty unanimous in that they
> didn't like it. My how things have changed in the last 22 years. And are
> likely to continue to change in the future.
>
> -Jeff Scott
> Cherokee Village, AR
>
>
>> Sent: Thursday, April 11, 2019 at 8:45 PM
>> From: "Mike Sylvester via KRnet" <krnet@list.krnet.org>
>> To: "Craig Williams" <cr...@kr2seafury.com>, KRnet <krnet@list.krnet.org>
>> Cc: "Mike Sylvester" <shagste...@hotmail.com>
>> Subject: Re: KR> Roger Baalmans plane
>>
>> I put the wheel pants back on N236MS and found some clear sky a few days
>> ago. WOT at 3000 level she pulls up to 175 mph indicated. That's with a
>> fresh O-200 with a Sterba 60x68. Your results may vary.
>>
>> Mike Sylvester
>> kr2s builder
>> Birmingham,AL.
>>
>> Cell no.205-966-3854
>>
>> ________________________________
>> From: KRnet <krnet-boun...@list.krnet.org> on behalf of Craig Williams via
>> KRnet <krnet@list.krnet.org>
>> Sent: Thursday, April 11, 2019 8:20 PM
>> To: KRnet
>> Cc: Craig Williams; Chris Matheny
>> Subject: Re: KR> Roger Baalmans plane
>>
>> I can give you an opinion from a guy who has been looking for the best of
>> the best options and what I am seeing with N886MJ.
>>
>> First, Larry is right. In my opinion this design has been pushed to its
>> limit. At this point most everything has been tried and the best options
>> are being used. If you build light and go as big as safely possible on the
>> engine (which I believe is ~125hp), you can achieve a 1300MGW and 150mph
>> cruise airplane(in a Tailwheel (TW) configuration). As soon as you try to
>> increase the MGW with more wing area your gonna slow the airplane because of
>> weight and drag and then your gonna need that 150hp to go 150. I have
>> actually changed engines on my build 4 times. First a Corvair, then an
>> O-200, then and O-235 and now I am back to a Corvair. Luckily I pretty much
>> broke even on all those engines. I am now headed twords the 120hp Corvair
>> with my TW build. My current 2S is a trigear and I am close to hitting that
>> brick wall with the 100hp Corvair in it. My top IAS is 150 at 1200lbs GW.
>> I have a few more mods to complete but I suspect I wont see much more speed.
>> Maybe 10 more if I am really, really lucky. I settled on the KR many, many
>> years ago because I wanted a 150mph cruise. It's looking now like I might
>> just get there with the 120hp and the TW configuration on my build plane.
>> Here is a video from a test I did a few days ago after I put the wheel
>> fairings on. Best I saw was 145 IAS @ WOT and about 134 in cruise so I am a
>> bit disappointed as I don't see this airplane getting to 150 cruise without
>> me and the plane each loosing 100 lbs.
>>
>> https://youtu.be/759DgW50A7U
>>
>> Craig
>> N886MJ
>> N232WJ under construction.
>>
>>
>> and the o-235 engine in it. Anything you would do different or
>>> change? I'll be starting a build this summer an want to do a 26' wing with
>>> the longer fuselage and wider tail and use a 150hp engine I'm developing
>>> now. Thinking 1300 max load. I'm curious of the performance you're getting
>>> with the 125hp engine??? Thanks
>>
>
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