Rotax 583 powered KR2

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Rudix
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Re: Rotax 532 powered KR2

Postby Rudix » Wed Apr 16, 2014 2:51 pm

A few more flying KR photos....
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Henni
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Re: Rotax 532 powered KR2

Postby Henni » Wed Apr 16, 2014 3:05 pm

Hi Rudi,

Dankie vir die bemoediging. Ja, daar heers groot misverstand oor die KRs en meeste van hul net bangmaak stories. Daar sou nie so baie KRs regoor die wereld gebou en gevlieg word as daar enige waarheid aan daardie stories was nie. Wonder wat Ken Rand teen vandag intwerp het as hy nog steeds met ons was. Dis so jammer dat hy teen alles wat hy geleer was gekies het om oor daai slegte weer te probeer vlieg. Pleks dat hy maar eerder net omgedraai het.

Ek het eendag met my MXII in 'n aankomende storm gevlieg. Die wolke was maar net eers nog donker, geen ander simptome nie. Toe ek onder die wolke kom sit ek my enjin af en vlieg vir amper twintig minute sonder om hoogte te verloor. Dit was eers toe ek genoeg gehad het dat ek besef het ek kan glad nie meer hoogte verloor nie! Groot vlieg les geleer daardie dag. You get old and bold pilots. You do not get old bold pilots.

Groete my vriend,

Henni
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Rudix
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Re: Rotax 532 powered KR2

Postby Rudix » Wed Apr 16, 2014 3:16 pm

Henni wrote:Hi Rudi,

Dankie vir die bemoediging. Ja, daar heers groot misverstand oor die KRs en meeste van hul net bangmaak stories. Daar sou nie so baie KRs regoor die wereld gebou en gevlieg word as daar enige waarheid aan daardie stories was nie. Wonder wat Ken Rand teen vandag intwerp het as hy nog steeds met ons was. Dis so jammer dat hy teen alles wat hy geleer was gekies het om oor daai slegte weer te probeer vlieg. Pleks dat hy maar eerder net omgedraai het.

Ek het eendag met my MXII in 'n aankomende storm gevlieg. Die wolke was maar net eers nog donker, geen ander simptome nie. Toe ek onder die wolke kom sit ek my enjin af en vlieg vir amper twintig minute sonder om hoogte te verloor. Dit was eers toe ek genoeg gehad het dat ek besef het ek kan glad nie meer hoogte verloor nie! Groot vlieg les geleer daardie dag. You get old and bold pilots. You do not get old bold pilots.

Groete my vriend,

Henni
Hi Henni!

Ja, dit is so jammer Ken het 'n fout gemaak en duur daarvoor betaal :( Die weer waarin hy gevlieg het was ongelooflik, kan nie glo dat iemand so 'n besluit kon neem nie.

'n Storm is nie jou maat nie, en hy was hoog bo 'n baie kwaai een, oppad af na die engin gaan staan het sonder brandstof het die vliegtuig nog ys opgetel ook. Geen engin, ys en geen sig, dit kan net een manier eindig.

Ek het nog nie kommentaar gelewer oor jou idee vir meer plek nie, dit lyk goed en ek is seker dit sal daai probleem oplos!

Hoop jy is nou ontslae van die griep, lekker middag,
Groete,
Rudi
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Re: Rotax 532 powered KR2

Postby Henni » Wed Apr 16, 2014 4:38 pm

Hi Rudi,

Ja, as 'n mens hoer sit kan jy vorentoe skuif, sommer baie ook. As ons kan vorentoe skuif, hoef die enjin nie meer so ver uit te skuif nie. Cg probleme iets van die verlede. As 'n mens hoer sit, is jou arms en skouers bokant die romp. Baie makliker om die canopy breer te maak en dan net die romp breer te mock met foam en veselglas. 'n Mens kan oorboord gaan en 'n baie breer binneruim so skep.

Ek kan dit alles doen want my enjin is ligter. Plus due KR2 romp is juis breer vorentoe. Daar gaan nie 'n header tank wees nie, so niks in pad van bene nie. Die ander fotos wys duidelik dat 'n hoer canopy nog steeds genoeg lugvloei langs die kante verby laat vir die rudder om effektief te werk. Solank die cg op die regte plek is en die romp nie soos 'n plat baksteen muur bo lyk nie, sal dit nog steeds baie goed vlieg.

Ons gaan verseker nie 'n beknopte aerie he nie. Mens kan nog verder gaan en 'n bagasie ruim skep wat van onder aan die inner spars vasbout wat lyk soos die van 'n Cessna Caravan. Daar is baie maniere om die cg vas te spyker solank as wat die enjin die gewig kan optel.


In elk geval, "only speaking my mind". Hierdie is slegs idees om te oorweeg en ek het baie van hulle...

Groete my vriend,

Henni
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Re: Rotax 532 powered KR2

Postby Rudix » Wed Apr 16, 2014 5:22 pm

Henni wrote:Hi Rudi,

Ja, as 'n mens hoer sit kan jy vorentoe skuif, sommer baie ook. As ons kan vorentoe skuif, hoef die enjin nie meer so ver uit te skuif nie. Cg probleme iets van die verlede. As 'n mens hoer sit, is jou arms en skouers bokant die romp. Baie makliker om die canopy breer te maak en dan net die romp breer te mock met foam en veselglas. 'n Mens kan oorboord gaan en 'n baie breer binneruim so skep.

Ek kan dit alles doen want my enjin is ligter. Plus due KR2 romp is juis breer vorentoe. Daar gaan nie 'n header tank wees nie, so niks in pad van bene nie. Die ander fotos wys duidelik dat 'n hoer canopy nog steeds genoeg lugvloei langs die kante verby laat vir die rudder om effektief te werk. Solank die cg op die regte plek is en die romp nie soos 'n plat baksteen muur bo lyk nie, sal dit nog steeds baie goed vlieg.

Ons gaan verseker nie 'n beknopte aerie he nie. Mens kan nog verder gaan en 'n bagasie ruim skep wat van onder aan die inner spars vasbout wat lyk soos die van 'n Cessna Caravan. Daar is baie maniere om die cg vas te spyker solank as wat die enjin die gewig kan optel.


In elk geval, "only speaking my mind". Hierdie is slegs idees om te oorweeg en ek het baie van hulle...

Groete my vriend,

Henni
Hi Henni,

Dit klink sommer baie insteressant! Ek sal bietjie op ZU-AMV gaan kyk, op haar kan ek nog maklik veranderinge aanbring, miskien sal dit my inspireer om weer aan haar te werk :oops:
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Dit sal 'n baie spesiale KR2 maak!

Groete my vriend,
Rudi
"Never be afraid to try something new. Remember that a lone amateur built the Ark. A large group of professionals built the Titanic." ;)
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Re: Rotax 532 powered KR2

Postby Rudix » Wed Apr 16, 2014 5:42 pm

Here are the instrument panels of VYZ and CGR, I prefer "steam gauges" for the primary instruments, after 30+ years in IT I do NOT trust electronics :shock:
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ZS-VYZ
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ZU-CGR

Since these photos were taken I have made a few small changes including a new radio and transponder in VYZ
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Leaving Saldanha and flying along the west coast in ZU-CGR
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Parked at Vredendal

These planes have the speed and range that allows you to really explore the country!
"Never be afraid to try something new. Remember that a lone amateur built the Ark. A large group of professionals built the Titanic." ;)
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Re: Rotax 532 powered KR2

Postby Henni » Mon Apr 21, 2014 2:50 pm

Surprise!

The complete aircraft is built out of wood, masterbuilder style. Even the wings are covered with wood ala Pulsar! All wood was covered with cegonite like a radio controlled aircraft which is off course no good for modifications. So all of this this will have to go. Doubt if I'll cover her with fibreglass as it will only add weight. Maybe I'll reconsider for the wings...

Dash will have to go to make space for new seating arrangement. Notice how far forward the occupants position is moved. Very, very, very good for the cg! The cg of someone sitting in an aircraft is normally their navel. So in this case the weight of both the pilot and passenger will be just about at the back of the main spar. This is right in the centre of the allowable cg range. One cannot place the human bodies at a better position. The rest of the aircraft/engine will balance each other out perfectly. In any case, this is as far as my 6 foot long body can move forward whilst still having proper rudder control. I can off course modify the bottom of the firewall ala Jabiru and move the rudder pedals forward - still thinking about this.

The landing gear and mount is very, very strong and the attachment the best and strongest I've ever seen. Will post some pics later. However, it's heavy and will need to go. So she WILL be changed into a nose dragger which is very good indeed. I am thinking of mounting the main wheels spring arm to the forward wing attach fitting. That way I do not need to cut away too much of the existing emphenage.

See my arm position outside the fuselage? New canopy will allow for this, giving much, much more space inside! I'll cut away most of the forward turtle deck, making it even roomier. My left arm will rest on the window sill with the T throttle just ahead of my hand. The passengers right arm will rest in the same position outside of the current fuselage. The front of the canopy will be ala Swearinghan SX300 style and will look super modern. The rear of the canopy will be ala BX Cherry, blending from above into the current rear turtle deck. It will all look modern and pleasing when done as I hate ugly!

All in all I'm elated with my project and my idea. She's going to be everything I've promised.

Cheers all,

Henni
Attachments
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AndyCAP
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Re: Rotax 532 powered KR2

Postby AndyCAP » Mon Apr 21, 2014 8:53 pm

Hi Hennie. I just came across this thread an have enjoyed reading it. I can see your enthusiasm for the KR and passion for getting into the sky. Its awesome and the core of what grassroots aviation is about. I do feel compelled to give you some input as a fellow big boned pilot (I weigh 110kg:oops:. )

I have always dreamed of flying and have had the fortune of being able to get my PPL which unfortunately currently is not valid since I cannot really afford to fly regularly enough to stay safe in my opinion. In a quest to look for cheaper options than bliks I have considered and researched many different 3axis aircraft most of which tended to be in the slower than the KR

I have never really been fond of trikes ( which in my mind is the cheapest way of getting in the air in a powered aircraft - not considering powered paragliders or powered parachutes).

What I have come to realise is that everything in aviation is a compromise. If you want something thats fast and capable of travelling significant distances, its probably not going to have short/rough field capability unless its quite expensive like the grassair sportsman. Flying is all about power to weight and wing loading. The higher the load the higher the wingloading and the faster you need to fly to stay airborne which in turn requires more power.

Getting back to your research on the KR 2's capability, I think one of the key things you need to ask of any person from whom you are getting feedback regarding Flying 2 up in a KR (or any plane which is operated within marginal parameters for that matter) is at what Density Altitude (DA) they are flying. Also what the weight of them and their pax is as well as the empty weight of the aircraft and how much fuel they had on board. In other words at what AUW they were operating for a given DA. It is critical that you make sure that the aircraft will be able to handle what you require so make sure the data you are looking at is enough to make sure you are comparing apples with apples

You need to define your mission to see what you need from a plane. In my case I wanted to be able to take another pax of around my weight (thus 220kg payload) and ideally full fuel. As an example both the cheetah and the bantam have a max usable weight of around 285kg which would give about 65kg to spare for fuel, oil and luggage. Not much as you can see since this will only allow for about 70liters of fuel (no baggage).

So. I suggest you do a similar calc and work back from the MAUW for the KR this will tell you what the empty weight of the plane has to be to fore-fill your requirements. You will soon see that weight is your biggest enemy and restriction. So you will have to look carefully at every modification you make that potentially adds weight. Thus carefully look at the impact adding flaps will have - it may not be as positive as you think! The wingloading is going to be the biggest determining factor of the airspeed required to stay aloft. The heavier you are the higher the required airspeed.

Lastly do not fall into the trap of underestimating the effect of flying up at the Reef. Having done 95% of my flying from FAGC i have learnt the huge effect DA has on a aircraft's performance. One particular event stands out in my mind. i took a guy up one afternoon at about 14h00 in a C172. I knew it was hot, but i figured since we were only 2 up and only had half tanks we should be ok. Besides, he was a skinny chap so i guess he only weighed about 75kg so our combined weight was only about 185kg. I had previously flown the plane with 3 up and full tanks with no problem..... But that was early one winters morning. I will never forget that takeoff when i barely managed to get 50fpm climb after leaving ground effect. I remember telling myself to fly the airspeed and selecting one field after the other for a potential forced landing sites during the initial climbout after takeoff. I only reached circuit height once I crossed the N14 Krugersdorp highway. I learnt a lot that day. DA is something always to respect and be aware of - all the more so at the reef.

The KR is an awesome little machine and I love the concept. The reason it is fast is that its quite small and aerodynamically slick, but mostly due to a higher wingloading and the type of airfoil used. But the price you pay is that its less forgiving at lower speeds an has relatively high stall speed

I think its good you are looking at an alternate seating position. Just be aware that you will need at least 50 - 80cm clearance for your headset and to allow for some vertical movement (turbulance). Also consider that your forward canopy / windshield shape and bracing must be such that you cant hit your head in a forced landing situation.
Raising the canopy can have a big effect on the directional stability and effectiveness of the fin & rudder, so you may need to increase its height to ensure it gets sufficient airflow. Keep in mind the KR is very short coupled so has not got a lot of directional and pitch stability in reserve.

Just some background on me to put my comments in context:
I have no flying experience on KR2
i have only 105hrs TT the bulk of which is on C172 and other bliks, with a few hours on cheetah912 and DA20
I am a mech. Eng and have extensive experience in designing, building and flying RC model aircraft from which i have learnt a bit about aerodynamics
I weigh 110 kg and am 2 m tall have had to come to terms that I was not really built to fit in aircraft and that in most cases my weight is about 1.5x the design weight that was used for the design of most light aircraft.

Please make sure you understand the capabilities and limitations of the KR and be realistic of what it will be able to offer you. Good luck with your project and stay safe!
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Re: Rotax 532 powered KR2

Postby Henni » Tue Apr 22, 2014 6:20 am

Hi AndyCAP,

Thank you so much for your informative mail mate. Highly appreciated.

Yes, I've already looked at all of these factors. Most KR2's weigh over 630 lbs empty. Some even as high as 750 lbs. The plans call for a empty weight of 480 lbs and a gross weight of 900 lbs using 60 HP only. Many KR2's have been flown at over 1200 lbs using a VW engine.

So, my scenario: I plan for her to weigh no more than 500 lbs empty, maybe even less. I also weigh in at 110 and my wife around 80 as we are both tall. I have 64 HP up front, albeit light. I think we'll be okay two up. If not, I'll change the Rotax with a 80 HP Jabiru later when I can afford.

As for the flaps, my only intention for them is during landings to slow her down even more. However, notice that the MCR uses properly designed flaps to haul 4 fully grown occupants into the air using only 100 HP! For a better comparison, look at Rudi's KR2. That VW with it's huge turbo's and two coolers is not light at all. Yet he regularly uses no more than 650 m of runway. Most KR2s, even the heavier ones, stall between 40 to 50 MPH. I'm sure mine will stall at a even lower speed than this putting it right there in the same category as the more basic microlights. a Bigger, slower prop gives more thrust. Maybe not so good for speed, but most certainly for getting two occupants away from the ground.

I have many hours in microlights, mostly with the Rotax 503. Most of those hours are two up. Yes, many a time I had to fly underneath power lines because on hot days it is extremely difficult to get away from the ground in that configuration. I know your scenario all too well.

So I'll have to wait and see as I want a full two seater. I'll do everything in my power to keep her light, mods and all. My cockpit layout change might not add much more weight. I plan to use thin mylar for windows with a support down the middle for the front section. And yes, to increase the rudder & make it higher is really no big deal & I have already considered that.

As a last resort, quite a few has increased their wingspan 2 feet on each side using a simple wing extension mod. There are many flying like that, so it is a safe mod. However, this will be my very last mod and only if absolutely required.

Anyways, nice chatting to you mate,

Henni
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Re: Rotax 532 powered KR2

Postby Henni » Tue Apr 22, 2014 8:18 am

Hi again,

My canopy will be a combination of all of these. The landing gear will be almost exactly like I did it before on this project, only I'll mount the main gear leaf springs to the rear of the main spar wing attach fittings. Steerable nosewheel will be the same as this. All controls will also be the same as these, only I'll have one centre stick only so as not to interfere with the forward fuel tank position. If needs be, I'll divide this tank into a left and right halve with the controls running through the middle.

Fuel tanks will most probably go right behind the main spar under the seats and right in front of the main spar under the legs without the need to open the wings again. That way I'll keep the cg in place under all conditions.

The fuel tanks are easy to make. First you shape it roughly using polystyrene. Next you cover it with PVA paint or so, and then cover it with fibreglass. When done, you put petrol in it which dissolves the foam completely leaving you with a fuel tank shaped to your choice!

Note how Jabiru moves the rudder pedals forward. I only need to bulge the firewall ply around the rudder section like this - no need to rebuild the whole of the firewall. Will post pics when done to show what I mean. Main engine mounts will still attach to the original firewall bulkheads.

So, she'll most probably weigh less than 500lbs, with the VG's stall under 40mph, cruise around 120 - 130mph two up at 18l/hour, be rather roomy inside (by KR2 standards that is), look not to shabby and she'll really be able to go places! I can't wish for more without having to be wealthy first...

Keep well all,

Henni
Attachments
C30.JPG
Front of canopy will be like this.
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Centre and rear canopy like this.
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Centre and rear canopy like this.
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Wheels like this.
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Wheels like this.
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Controls like this.
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Controls like this.
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Controls like this.
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Extending the KR2 wings.
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Extending the KR2 wings.
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Extending the KR2 wings.
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Extending the KR2 wings.
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Extending the KR2 wings.
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How Jabiru solves the rudder position problem.
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Re: Rotax 532 powered KR2

Postby Henni » Wed Apr 23, 2014 6:44 am

Hi all,

Found something interesting for those seriously interested in aerodynamics:

Airworthiness analysis of a modified KR2 experimental aircraft

The KR2 in formulas and numbers


Here are more interesting reads:

2010 KR2 Mishap

and another one:

The KR2 was designed by an Electronics Engineer.


Here are some really heavy KR2s:

"The empty weight of Bob's airplane was more than 790 pounds". Keep in mind that the designed empty weight was a mere 450 pounds!

Mark Langfords

• Empty weight: 760 pounds - 450 pounds called for in the plans
• Gross weight: 1200 pounds - as opposed to the 900 pounds in the plans
• Fuel capacity: 16 gallons
• Top speed: 191 mph TAS (true airspeed) with 3100cc Corvair engine and Sensenich 54x54 prop (turning almost 4000 rpm), 184 mph TAS with Sensenich 54x58 (but turning only 3400 rpm, and burning less fuel).
• Fuel consumption: I get 42 mpg while flying at 160 mph TAS at 10,000' running "lean of peak", which is how I always fly at altitude.
• Stall speed: 57 mph with split flaps deployed, 62 mph "clean" - 45 mph in the plans
• Glide ratio: 11.8:1 engine at idle or engine stopped (almost the same number)at about 80 mph, averaged from 10,000' to 2,000'.
• Propeller: currently a wooden Sensenich 54 x 58. I've tested at least 10 different props, and this one gives me the best speed and economy with a reasonably low engine speed.

So, this is really one versaltile aerie with extremes to all sides currently flying and flying well. Mark has close to 1200 hours on his heavy KR2 which says a lot for the design!


Keep well all,

Henni
Attachments
bob.jpg
Heavy KR2
06102822m3.jpg
Another 760 pounder...
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Re: Rotax 532 powered KR2

Postby Henni » Sun Apr 27, 2014 7:23 pm

Hi all,

Purchased some more aluminium and also some much required tools. I also fabricated some more parts. Will take pics on Monday & post some over here. I've decided to first finish the engine mount before I continue on the fuselage mods. I can now at least focus on making the engine fit inverted inside the stock standard KR2 cowling. No need to hang it all the way out there in the front any longer. I think my engine should be hanging by mid this coming week. Then I can start mounting the radiators & plumbing. Looking forward to it.

Also, received my engine vibration rubbers from Boet, so I now have everything required to mount my engine. I also have enough aluminium to mount my new fibreglass seats in their new position. By the end of this coming week, if all goes well, I should be able to show some good progress.

This is where I purchase all my aluminium from - virtually just around the corner from where I work! What a blessing indeed...

And last but not least: My project is now also listed over at the KRNet.

Keep well all,

Henni
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Photo0014.jpg
Photo0018.jpg
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Re: Rotax 532 powered KR2

Postby Rudix » Sun Apr 27, 2014 7:51 pm

Great stuff Henni!

Nice to see the progress, soon she will fly!

Yes, saw your link on KRNet but it does not work. The : was left out of the http:// bit. I have 2 links there, think I need to add ZU-AVM, I am keen to do some work on her but for that I need to take her home, little work gets done at Rhino as it is more fun to fly and chat to buddies when you are there..... I want to take the 601 to Rhino and will then take the KR home.

I ran ZU-CGR's engine yesterday with the new prop, she is now getting the rpm she should so shorter runways should be ok again! Even after standing for a while she ran like clockwork, the fuel injection and electronic ignition is really working well.

Have fun with the build my friend, chat soon,
Rudi
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Re: Rotax 532 powered KR2

Postby Henni » Mon Apr 28, 2014 5:34 pm

Hi all,

Rudi, thanks for the info on the broken link. Asked Mark to fix. Great about your new prop. Please let us know the outcome after your first flight with it.

Ha, I just checked out the new link over here and it now works! So now I'm also on the hall of fame...

So, today I started with the new seating position. The caption below each photo says it all. Tomorrow I'll continue with the other aux. tube supports and glue all of them in place with tube inserted. I plan to have three pieces of laminated ply at each side to hold the tube in place. I had to use three thinner pieces as they need to bend to the shape of the outside (skin) ply when I glue them in place, one at a time.That way it will be strong enough to support the seats to the rear and also the shoulder harness to the front. I think this was a good idea. Light and strong and no other brackets have to be made and no holes need to be drilled through critical support structures.

The seats will hinge forward from the main spar and will rest against the new tube at the back and via supports I still need to make on the bottom tubes below the spars. I need to be able to hinge the seats forward as one of the fuel tanks will fit nice and snugly below the seats, resting also on the bottom tubes. The lap seatbelts are already attached to those tubes. The shoulder harness will be attached to the thick walled aircraft grade tube behind the seats, the one I'm busy installing.

I really have nothing but praise for the previous builder. Everything is well thought out and built to a very high standard. Such a shame that he could not live long enough to see his dream all the way through. I think about him often & I feel so sorry for him...

I desperately need a sanding block. So will make one first thing in the morning.

Keep well all,

Henni
Attachments
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Original seatback will have to go!
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Gone!
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Polystyrene will also gave to go!
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Gone!
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No longer required.
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This will hold the tube behind the seats.
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First one done.
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Other side.
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Two main tube supports.
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First aux tube support
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Hard at work.
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Original seatback found a new purpose.
Keep grassroot aviation alive!
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Henni
Pilot in Command
Pilot in Command
Posts: 807
Joined: Tue Jan 16, 2007 10:58 am
Location: Pretoria

Re: Rotax 532 powered KR2

Postby Henni » Tue Apr 29, 2014 4:17 pm

Hi everyone,

Ha! My wing has now become my favourite place for placing everything I intend to photo capture.

This is where I now stand after another day's work. Progress is rather slow as I'm not working from plans, but applying ideas as I go along. See the caption below each photo for description. I did not have to make a sanding block after all. I purchased a ready made one instead. Also found the glue of my choice, so now I feel much better. For serious bonding, I'll purchase the stuff that Piet Propeller uses direct from him, but no need for that as yet...

Tomorrow I'll glue the back seat support tube in place. All parts have now been fabricated. I just need to sand the fuselage inner skins & stringers before I start for proper glue contact.

When I cut the tube to fit, I realized anew just how much the KR2 fuselage widens to the front, where it is not required. Our new shoulder position will now at least coincide with the widest fuselage position. This along with the extra elbow room I'm going to create, will make a HUGE difference to a stock standard stretched KR2 interior. I am well pleased with my ideas and slowly everything is coming together exactly as foreseen.

You can clearly see just how far forward the occupants were moved. Remember that the top seat back position was far behind the rear wing spar. Now it is at least completely to the front of the rear spar. I can still control the rudder pedals with ease with my 6ft body, but there is a good chance that I'll bulge the firewall in the rudder pedal area and move the pedals forward, just because it CAN be done!

I am also now even more convinced that she will turn out to be everything that I wanted and a proper, fully able full two place aerie. Not sure if I can call it a KR2 anymore. However, I'm rather convinced that in future many other builders will follow in my footsteps as the results will just be amazing considering that it started off as a standard KR2. I'm also convinced that when she flies that we'll see more two stroke powered KR2s all over the word as this design was meant to be light right from the onset.

Heck, I might even be a trail blazer for this new concept... To design something like this and build it from scratch can be done with ease, but to radically change something that has already been build without tampering with the load bearing components requires just a little more head scratching.

Keep well all,

Henni
Attachments
WP_20140429_001.jpg
Sanding block & my favourite wood glue.
WP_20140429_002.jpg
Tube support parts.
WP_20140429_006.jpg
This is how they will be used.
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Tube cut & shaped for a tight fit.
WP_20140429_008.jpg
See just how far forward the seat back has been moved.
WP_20140429_009.jpg
See just how far forward the seat back has been moved.
Keep grassroot aviation alive!

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