Another NEW Savannah XL on its way

[rankamateur]

Reg's super Savannah is 2 inches longer again and it still rotates fine but does have the battery in the back, and a gob full of power.

 

 

[Kyle Communications]

Hank

 

The XL is 5 inch wider and 4 inch longer in the cabin...they had to move the firewall forward as the rest from the seat forward is the same. By going to the ring mount for the engine the engine is also further forward. hence the reason for being nose heavy. It flys fine but you can feel the nose as you land especially as the speed drops off it is hard to keep the nosewheel off the ground after landing. I will start by putting the tiedown kit in the back but I think the battery will be transferred to the back eventually after I do some further loading down the back. I need to shift the fully loaded weight back to around 450mm or 480 mm CG point further back then it will be really good to be able to drag her in as you want. The teltail is the trim adjustment on the elevator. Mine flies with the trim tab around 10mm up when you hold the elevator level with the servo trimmed fully in...the book says 30mm is this measurement but most I have seen are around 20mm up for the same. I will take it to that point first then go a little further and see.

 

Reg also has the airmaster on his so thats another 8 or so KG on the nose as well

 

Mark

 

 

[eightyknots]

HankThe XL is 5 inch wider and 4 inch longer in the cabin...they had to move the firewall forward as the rest from the seat forward is the same. By going to the ring mount for the engine the engine is also further forward. hence the reason for being nose heavy. It flys fine but you can feel the nose as you land especially as the speed drops off it is hard to keep the nosewheel off the ground after landing. I will start by putting the tiedown kit in the back but I think the battery will be transferred to the back eventually after I do some further loading down the back. I need to shift the fully loaded weight back to around 450mm or 480 mm CG point further back then it will be really good to be able to drag her in as you want. The teltail is the trim adjustment on the elevator. Mine flies with the trim tab around 10mm up when you hold the elevator level with the servo trimmed fully in...the book says 30mm is this measurement but most I have seen are around 20mm up for the same. I will take it to that point first then go a little further and see.

 

Reg also has the airmaster on his so thats another 8 or so KG on the nose as well

 

Mark

Oh, I see, I thought you were telling me that there was a new XL design but now I realise you were comparing it with the old VG/classic Savannahs.

 

The figures say that the XL and S versions of the Savannah are the same but I would have imagined there to be a weight difference because of the different fuselages. For some reason it must be so small that it doesn't register.

 

When I get around to building my plane I am thinking of possibly fitting a Viking engine so save on the powerplant cost and because it has fuel injection. If however, the finance could s-t-r-e-t-c-h far enough I could consider a Rotax 912 injected. An Airmaster prop would be a nice addition to the wish list as well as a glass panel cockpit but $$$$ will eventually be the guide to what it comes with. Looking at the weight issue alone (and forgetting the dollars) the effect on weight as far as I can see is:

 

Rotax 912S (extra weight ahead of CG)

 

Viking engine (extra weight ahead of CG)

 

Airmaster prop (extra weight ahead of CG)

 

Glass cockpit (less weight ahead of CG)

 

Jab-style static port (more weight behind CG)

 

I also would like to know the effect on CG for these optional items:

 

BRS-style chute

 

long-range fuel tanks

 

extended luggage area

 

Mark, perhaps you could comment on those three?

 

 

[Kyle Communications]

The 912S is the "standard" install here the viking is heavier and of course a csp will further make it more nose heavy. The BRS is so close to the CG it really doesn't matter the long range tanks again are close to the CG the extended baggage area again is not that far from the CG but with 20kg in there then yes it will make a slight difference. The major changes to CG of course is the weight around 1 mtr or more infront or behind the CG position. Glass cockit actually are probably lighter than the original steam gauges.

 

Dont get me wrong Hank the Sav flies great and has no vices and I am very pleased with her but I want to get it as close to perfect as I can. With my almost 40 years of model aircraft I KNOW the difference in how a aircraft flies when you have the CG in the right spot. This will make the low speed handling even better than it already is it will also enhance the stol performance greatly. This process will be a slow and steady one you never make big changes in the CG area as it can bring disaster as you realise.

 

 

[Kyle Communications]

I also forgot the larger nose wheel puts another 2 kg onto the nose weight

 

 

[eightyknots]

It's interesting that, with the exception of the glass panel instead of steam gauges, most improvements make the plane front-heavy. Either the 912S or the Viking probably adds 7+kg, the Airmaster about 7kg (and its further away from the CG so has a greater effect) plus the larger nosewheel. All up, perhaps 16+kg.

 

(Perhaps a small truck battery in the back will balance it out ...OR, extra thick paint on the fuselage?)

 

 

[Kyle Communications]

Hi Hank

 

I have been playing around with the balance figures and when I get access to Dieter's proper balance beam scales I will do proper measurements with actual weights in the right places and up to MTOW and a bit beyond to make sure the figures are correct. You have to remember that the new XL and the S models the firewall is 4 inches further forward the engine is now on a ring mount which puts the engine another 4 inches further forward and then there is the 5 inch prop extension that puts the prop 5 inches further forward again. THEN they have shifted the battery from the back to the front albeit just behind the CG position.

 

As you load a savannah up the CG goes back so theoretically when the aircraft is fully loaded and say 10% overloaded as a safety factor the CG should be within the graphs but towards the rearward safe CG point and NOT beyond in any way. That way when you fly it with say a 70kg pilot and min fuel say 30 litres the balance point still needs to be behind the most forward point on the graph or preferably as far back from the nose heavy position as possible.

 

I have redone my totally empty w&b figures and looked at the balance then I put myself (125kg) in with 57kg of fuel then I loaded it up in 2 other ways one was with me and full 115kg of fuel which puts it at exactly 560kg and another with pilot and pax and enough fuel to load the aircraft up to 600kg which of course it not to be done that is 40kg over MTOW but I used it as a safety measure. I plotted this on the graphs this is with the Sav in its current standard config and at 600kg the cg is only halfway between the max and min areas of the graph this in my opinion makes the aircraft way to nose heavy. The balance point needs to come back even further to at least half way between the current point and the most rear ward position allowable and possibly a little further this will of course bring the CG forward again when the aircraft is lightly loaded but a fair way back from the standard position. I will scan some of the graphs and post them to show you but the real proof will be when I get access to these scales and actually load the aircraft and measure the weights on the wheels at these weigts then I will have actual real world numbers to play with.

 

The attached pic is Dieter and the scales when I did the initial weighing

 

Mark

 

 

 

[Kyle Communications]

Picture showing the weights and where the balance is the graphs you can see I am no where near the rear point and I have put the point on where I would like it to be

 

 

 

[eightyknots]

Hi HankI have been playing around with the balance figures and when I get access to Dieter's proper balance beam scales I will do proper measurements with actual weights in the right places and up to MTOW and a bit beyond to make sure the figures are correct. You have to remember that the new XL and the S models the firewall is 4 inches further forward the engine is now on a ring mount which puts the engine another 4 inches further forward and then there is the 5 inch prop extension that puts the prop 5 inches further forward again. THEN they have shifted the battery from the back to the front albeit just behind the CG position.

 

As you load a savannah up the CG goes back so theoretically when the aircraft is fully loaded and say 10% overloaded as a safety factor the CG should be within the graphs but towards the rearward safe CG point and NOT beyond in any way. That way when you fly it with say a 70kg pilot and min fuel say 30 litres the balance point still needs to be behind the most forward point on the graph or preferably as far back from the nose heavy position as possible.

 

I have redone my totally empty w&b figures and looked at the balance then I put myself (125kg) in with 57kg of fuel then I loaded it up in 2 other ways one was with me and full 115kg of fuel which puts it at exactly 560kg and another with pilot and pax and enough fuel to load the aircraft up to 600kg which of course it not to be done that is 40kg over MTOW but I used it as a safety measure. I plotted this on the graphs this is with the Sav in its current standard config and at 600kg the cg is only halfway between the max and min areas of the graph this in my opinion makes the aircraft way to nose heavy. The balance point needs to come back even further to at least half way between the current point and the most rear ward position allowable and possibly a little further this will of course bring the CG forward again when the aircraft is lightly loaded but a fair way back from the standard position. I will scan some of the graphs and post them to show you but the real proof will be when I get access to these scales and actually load the aircraft and measure the weights on the wheels at these weigts then I will have actual real world numbers to play with.

 

The attached pic is Dieter and the scales when I did the initial weighing

 

Mark

That's interesting. It seems that the XL+S Savvy is really biased to a front-heavy W&B after the lengthening mod. I agree, when fully loaded the CG should be nearer the rear limit. The issue now will be: how will this be achieved easily?

 

 

[Kyle Communications]

I have been doing some rough calculations on the weight required....it looks like by shifting the battery back 8.5 kg the extra wiring 1.5 kg and the tiedown kit 4 kg that is 14 kg total in the back it still does not bring it back to anywhere I would like it to be. It does bring it back but still not far enough it looks like it needs around 20kg at least in the tail to get it back there but this is with fudge figures I will know when I can get the aircraft on the scales and actually shift some weight around and do actual measurements and then I will know.

 

 

[Kyle Communications]

Hi All

 

Today was the big day. I had pretty much everything together and a few things had to be made up. The forward battery position was going to be a pain as I have other DC stuff coming off the battery like my ERPS and my charging/jumper jack and I didnt want to rewire everything to the back so I decided to make p a busbar system that would attach by rivets to the old battery position and I could just connect up the new cables from the battery and leave all the other cables going to my isolation switch and the negative that goes to the earthbar under the dash then out to the solenoid base and off to the starter. I used some 2 mm angle alu with a right angle bend at the forward end to butt up against the skin and one of those plastic cutting board to make a frame up that riveted to the main vertical longeron and one of the skin longerons it is spaced the 40 mm from the skin and solid as a rock mounted. the 2 busbars they are made from 5 mm brass stock and tapped for 8mm for the main battery cables in and out and each busbar has 4 of 4mm tapped holes to be able to attach DC to then, 2 of these are taken up by the erps and the charge jack. The pic attached isnt that great but it gives you the idea and there is no possibility of shorts as there is heaps of clearance on both the busbars are attached by 4 bolts each to the plastic insulator.

 

I weighed the aircraft with the bathroom scales it ended up only 1 set were reasonably accurate the main difference is the nose wheel weight came back to 58 kg previously it was 72.5 kg that is a massive difference. I will get some very accurate scales to do the proper weights but this is well and truely close enough. I have done the new weight and balance graph and it has come not pretty much spot on to where I posted the picture before so my calculations were pretty much spot on. My "X" has gone from 284 mm to 345 mm I am happy with that the aircraft will definitely fly much better at this new point. I need to adjust my trim tab before I fly her as I am sure it will now come back to where I think it should have been if I fly her now at this current trim position it will be climbing a lot I won't have enough forward adjustment. I will do this tomorrow and put some fuel in her and go for a fly if the weather looks ok. I would prefer to do it early when the conditions are good so if not tomorrow then wednesday morning before I head up to the farm for a few days

 

 

 

 

 

[Kyle Communications]

On another subject Ken Wright from Kilcoy "Dags" dropped in this morning with Hans and Phil to have a cuppa with Roger Western and to also bring the bungee remover/installer that John Gilpin designed for savannahs so that Graham Pukallus could change his bungee there is a pic of the old one in the bungee thread anyway ken has had a issue with his back and couldn't get comfortable so he came up with a stick mod so he could stretch his leg out also turn the centre stick into a between the legs stick. I jumped in and took a few pics I have to say it feels really nice. The stick is removable and the original can be put back. I might do this sort of mod at a later date to try it in mine. His stick isn't quite in the centre due to the flap lever when the flaps are fully down but my flap lever is somewhat different as you may remember and my stick could be made directly in the centre. I wont be doing it now but it could be a great mod for later as I do find the centre stick a bit of a pain sometimes as I am right handed so during navs etc when it yes lumpy my right hand is tied up doing the flying it would be better if I could have my right hand free

 

 

 

 

 

 

 

[eightyknots]

Hi AllToday was the big day. I had pretty much everything together and a few things had to be made up. The forward battery position was going to be a pain as I have other DC stuff coming off the battery like my ERPS and my charging/jumper jack and I didnt want to rewire everything to the back so I decided to make p a busbar system that would attach by rivets to the old battery position and I could just connect up the new cables from the battery and leave all the other cables going to my isolation switch and the negative that goes to the earthbar under the dash then out to the solenoid base and off to the starter. I used some 2 mm angle alu with a right angle bend at the forward end to butt up against the skin and one of those plastic cutting board to make a frame up that riveted to the main vertical longeron and one of the skin longerons it is spaced the 40 mm from the skin and solid as a rock mounted. the 2 busbars they are made from 5 mm brass stock and tapped for 8mm for the main battery cables in and out and each busbar has 4 of 4mm tapped holes to be able to attach DC to then, 2 of these are taken up by the erps and the charge jack. The pic attached isnt that great but it gives you the idea and there is no possibility of shorts as there is heaps of clearance on both the busbars are attached by 4 bolts each to the plastic insulator.

 

I weighed the aircraft with the bathroom scales it ended up only 1 set were reasonably accurate the main difference is the nose wheel weight came back to 58 kg previously it was 72.5 kg that is a massive difference. I will get some very accurate scales to do the proper weights but this is well and truely close enough. I have done the new weight and balance graph and it has come not pretty much spot on to where I posted the picture before so my calculations were pretty much spot on. My "X" has gone from 284 mm to 345 mm I am happy with that the aircraft will definitely fly much better at this new point. I need to adjust my trim tab before I fly her as I am sure it will now come back to where I think it should have been if I fly her now at this current trim position it will be climbing a lot I won't have enough forward adjustment. I will do this tomorrow and put some fuel in her and go for a fly if the weather looks ok. I would prefer to do it early when the conditions are good so if not tomorrow then wednesday morning before I head up to the farm for a few days

I'm glad that the W & B issue has now been successfully resolved. What CSA cable did you use to the back?

 

I am sure that flying will be much better now.

 

 

[Kyle Communications]

The extension cables are flexible multi strand sort of like almost welding cable. the positive is 25 sq mm or roughly 4 gauge and the negative is 16 sq mm. The negative is not connected to the frame at the new battery position at all. it is connected to the same original position off my busbar frame connection and it continues on to the earth bar under the dash then onto the base of the starter solenoid inside the engine area firewall then onto the motor so no changes there. So really just a extension. I haven't started the engine yet but I don't expect any issues at all as I haven't redone my trim tab yet I hope to get there late today to do that but it looks like I wont be doing any flying anyway the weather looks really bad this week and its pretty hot and a bit stormy today anyway. I am away until next weekend this wednesday but I do at least want to fly it on sunday next weekend so hopefully the weather is ok by then. I want pretty calm conditions to do the initial flight and final adjustments. I will see how she flys but I haven't put my tiedown kit in the rear yet so that should make it even a little better but will do this in steps as you would

 

Mark

 

 

[Kenny]

Hi Mark I meant to tell you on Sunday Jalipino ( John Nuyan) has three sets of accurate scales which can weigh all three wheels at once His strip is just west of Watts .

 

Cheers

 

Dags

 

 

[Kyle Communications]

Hi Ken

 

Yes I have flown over Johns strip. I borrowed some scales and for the testing they seem ok and reasonably accurate so for the weight and balance testing it is fine. Jim G has a set he offered that they use to weigh race cars that are extremely accurate and will make it easier so I will do a more accurate one to confirm but what I have used so far seems to pan out what it should be. I havent test flown her with the new CG yet that hopefully will be on sunday morning coming as I am away up at the farm for the next few days then if it all feels right I will be heading out your way

 

 

[Kyle Communications]

Gundy called into the farm this morning to drop a sav fuel tank off to me. The wind backed off thank god today it was blowing its naughty bits off the last 2 days...35 knots at least but dropped to about 15 today. here is a short video of his landing and takeoff.....as you can see we need some rain up here...the cows have mown the full 125 acres like a bowling green

 

 

 

[JimG]

Awesome Mark, having your mates drop in like that ....!

 

I reckon your farm will be on my 'things to do list' in 2013.

 

Cheers

 

JimG

 

 

[Kyle Communications]

Yes it will be better when I actually live here. I will bring the tank over and see how it goes in your Karatoo wing...I think it maybe a bit too thick but can easily make another top

 

 

[Gundy]

It was good to catch up. It took me 1.3 hrs to get there and .9hr to get home. Most enjoyable. I think you should fly your plane up after Xmas Mark and I'll pop down and show you around. Gundy

 

 

[Kyle Communications]

What a different aircraft

 

The girlfriend was flown today with the new CG. I was a bit concerned as I was filling her up with fuel today to test fly her I knew it would be safe as it is well inside the parameters but being a low time pilot I thought it best to enlist a expert to give her a whirl I saw that Neil Shaeffer from GoFly was there this afternoon and he has a Savannah S and also does stol courses so I asked Neil if he would take her up as I wasn't confident to do so as I didnt know what to expect so better to be safe. Neil kindly came over and test flew her as I had readjusted the trim position to where I thought it would now be but told him that obviously to be ready if I was wrong. He took off on 06 with me watching on beside the strip then the plane pitched a bit and the engine note changed a lot...damn near had a heart attack at the side of the strip then he took off to wide blue yonder to do some stalls to make sure it was all ok and also trim etc with flap on. when he got back i asked him about it and he was checking that the nose still pitched down when the power came off and of course it was but I just didnt expect him to do it then....but he did because he had plenty of strip to get back down in case it was a handfull

 

He arrived back and landed and was running up the strip with the nose wheel off the ground a bit at a reasonably slow speed......I could not keep the nose up like that before unless I was pretty much at flying speed. Previously my trim was set so level flight was 3 bars down from the top on my trim indicator in this position the manual tells you to setup the trim tab 30mm up when holding the elevator level with the servo fully retracted most factory sav's I have seen this is set to around 20mm...mine had to be set at just under 10mm to achieve this. After shifting the battery I reset my trim tab to the 20mm position before flying as I thought this would be close. Well now level flight is 4 bars from the top I have not put my tiedown kit in there yet at the back and I think this will be just perfect. I will make a removeable cover on the other side of the fuselage opposite battery and a small light box in there to put it in this of course will move my CG back a little further but not a lot of course I will do more weight and balance checks before it flys again like this

 

Now for me flying her. I felt much more confident after Neil confirmed the trim position so I took her out to 06 and took flight. Normally I would have to hold a fair amount of back stick to try to make the nose a bit lighter but usually I had to keep it there and around the stall warning going off I usually had to keep the back stick on or just give a bit more of a squeeze back and she would rotate. Well now what a difference only a little bit of back stick and around 20knots the nosewheel will lift off slightly and she flys off easily when the stall warning goes off that is set to 32 knots and I had about 10 knots on the nose this afternoon so she got off real quick. The first thing I noticed was I wasn't dragging the nose up it was pretty much effortless to keep the nose on the sweet spot at 60knot climb out speed...she felt really nice much lighter than before. I flew out toward Bribie and climbed up to 3000 ft and came back over Hazelton which everyone knows around the area it also has a nice grass strip there for practicing forced landings. I did my HASSEL check and did quite a few stalls...again a major difference. Before in a stall the plane wouldnt really buffet before the stall she would sort of get to a big mush then the nose would drop appreciably..now I can easily get the nose up quite well and there it was a nice little buffet and the nose dropped but not severely nice and controllable...such a nice stall now. After that I thought I better try the flap handling while up there so slowed her up to 50kts and put out first stage of flap adjusted the trim fully back and she wanted to sit around 55 kt hands off so just slight back pressure to keep it around 50kts usually I am usually around 47knots on approach and it was super nice too ,max flap extension speed in mine is 52 its, so I went back and joined downwind for a touch and go. pulling the throttle at the end of the strip on downwind the plane was much easier to slow up as I am not dragging the nose up to get back to flap speed..this was much easier ...then out with the flaps and I have to say the setup for approach from base was perfect.... landed just inside the threshold and the roundout was soooooo much easier and nicer did a greaser touch then off again for another circuit. Did the same on the second circuit and it was a beautiful touchdown on the mains and I decided to see how long I could hold the nosewheel up for without any power...I couldnt believe how easy it was to keep the nose wheel off the ground for so long I could never do that before the nose always wanted to come down almost immediatly after touchdown.

 

Now dont get me wrong the plane flew very well before and I have got around 50 hours on her now and I have enjoyed every minute but I knew how nose heavy she was and also knew if I bought the CG back she would fly even better. Well the proof of the pudding is in the eating...just a fantastic difference now she now flys so much nicer....so good infact I will have to relearn her a bit more to feel fully comfortable with her as I did before the modification. I am one happy camper tonight so much so I am off early tomorrow to get some more hours up in her

 

Mark

 

 

[rankamateur]

When will you ever get any work done?

 

 

[Kyle Communications]

Now come on Steve....your a long time dead I have to get things done...anyway I have been working my backside off the past 3 days up at the farm...back to the real world this week though but I am only open this week but it looks to be pretty busy then I am off on holidays from the 21st and back on the 7th of January will be spending about 8 or 9 days up at the farm then. The plane hadn't flown for about 3 weeks it really only took a day to do the mods so have been working through out that time...not enough time spent with the plane the past 3 weeks to be honest. I have had withdrawl symptoms.

 

 

[rankamateur]

It is nearly three weeks since I have flown, I think I am having continuity problems, don't know if I will be able to remember my check lists.

 

 

[Kyle Communications]

Withdrawl symptoms Steve. Give Reg a ring take 60 litres of fuel with you and ask him if he wants to go for a fly with him in the right hand seat. I know all about those symptoms. I went out to Kilcoy this morning the plane flys different in level flight as well it is far easier to keep levels very close and the landings are soooooo good now much more controlable also side slipping seems much better and more slipping as well the nose is much easier to control during the slip. Being able to hold that nose up easier allows for much better greasers I find now as well I can really put it onto the spot now when landing as when I have the flap out she seems much more controlable in sink rate although coming into YCAB on the return leg she didnt want to come down. Got about an hour or so in the new config and she is much better so I would recommend to get the CG back in a XL to at least 345mm it will probably come back to 350 or 355 mm by the time I am finished getting the new second rear door in beside the battery on the other side of the fuselage which I will put the tie down kit into.

 

Mark