My Savannah S model rebuild Blog

[Kyle Communications]

Hi all

 

I have just purchased a Savannah S model that had a unfortunate mishap earlier this year. It had been written off so I bought it to rebuild it and to make it better ( in my opinion ) and I will then use it as my own aircraft. The "Girlfriend" my XL will then be sold and I will use that to buy the next project to build. The airframe and engine has 350 TT.

 

I expect this to take somewhere between 12 and 18 months to do depending on the other projects I have going on. But I really miss working on a aircraft I find it challenges the mind and is such a stress reliever.

 

I have just done the over 2000 km round trip to pick it up and bring it home and it will be a week or so while I clean up my mess of a garage to give me the room to do all of this. I will post plenty of pictures of the progress and what I am doing. This also is for my requirement now with documentation etc for the new Tech manual rules.

 

The fuselage is broken in the rear and the rudder is damaged. The wings are pretty damaged but the ribs are pretty much all ok and I can get spares if any are damaged. The main wing spars look damaged at this stage but wont know the full story until I get the skins off. The engine needs the gearbox and mainshaft and crank checked but thats no drama either. The main cabin frame and centre main cockpit section all look good so far. It needs a new firewall and noseleg and a few other bits in that area but they are easily made

 

The plan is to make new wing skins the top skins and the front D skin will be 0.020 the underneath and flaperon skins will remain 0.016. The large flat fuselage side skins will be 0.020 but the top.bottom and curved sides will remain 0.016. The main wing spas if they are stuffed which I believe they are I will build new ones. The main web is 0.025 and I will make it 0.032. These sheet thickness mods should add enormous strength to the airframe but only add around 3kg to the total weight

 

Thats a hell of a lot of holes to drill you say? I will buy the sheet material all 6061T6 of course but I am drawing up the skins and the spas and I will get them lasercut locally so the sheets will all end up like what you get in the kit and also as accurate with all the holes lasered and you just need to do the riveting. At this stage I will buy from ICP probably 3 frames for the fuselage rear that look damaged and the rudder I will de-skin and either fix the frames or just fold up new ones to the correct size

 

I will upload some photos shortly

 

Mark

 

 

[Kyle Communications]

Some pics

 

 

 

 

 

 

 

[Kyle Communications]

I have started the Dskin and the main spar drawings..not finished yet but not far off

 

 

 

 

[rotax618]

Great project Mark, from the outside the wing spars look to be bent where the outer spar extensions join, if that turns out to be the case the wing rebuild should be easy, unlike Danny's where someone took to the spars with a jigsaw. Will call up after Xmas and give you and Danny a hand now I have new knees.

 

 

[IBob]

Ouch...cowboys, eh?

 

Stall or pancake in, then struts folded on impact????

 

 

[Head in the clouds]

Great stuff Mark.

 

Looking forward to watching the rebuild.

 

 

[rmorton]

Hi all

I have just done the over 2000 km round trip to pick it up and bring it home and it will be a week or so while I clean up my mess of a garage to give me the room to do all of this. I will post plenty of pictures of the progress and what I am doing. This also is for my requirement now with documentation etc for the new Tech manual rules.

 

Mark

Who are you trying to kid we all know a real mans garage can't be cleaned up in any less than a life time!

 

Looking forward to seeing this one progress. The damage looks bad but I guess when you start to strip it back it soon becomes what can be salvaged and what needs to be replaced.

 

 

[Kyle Communications]

Ouch...cowboys, eh?Stall or pancake in, then struts folded on impact????

Hi Bob

 

I spoke with the owner about the crash and it seems when he took off he peeled around fairly quick to the left just after takeoff on his homestead strip and wind shear...probably a big tailwind burst arrived and the aircraft then dropped out of the air with the left tip hitting the ground the tail then hit and then the right tip hit then the nose came down and broke the prop and bent the nose leg sideways. The cowl only has a very small smack on it underneath which will take about 30 mins to fix. He also said he could not believe when he got out and looked himself over that he pretty much didnt have a scratch on himself. The complete centre cockpit looks fully intact and no damage at all and not bent in any way. He said the strength of the aircraft and how the cabin protected him was amazing.

 

Who are you trying to kid we all know a real mans garage can't be cleaned up in any less than a life time!Looking forward to seeing this one progress. The damage looks bad but I guess when you start to strip it back it soon becomes what can be salvaged and what needs to be replaced.

I think it actually looks worse than it really is. I built my XL in my big garage and even full assembled it in there to set all the angles of the struts and surfaces. Over time though I have accumulated much more "crap" also the mother in law now lives in a granny flat that was built in the back yard so a lot of her stuff is stored in my garage so all of that will have to go back into her shipping container which I have to rearrange to fit all of that stuff into and I just have to bite the bullet and get rid of all the stuff you accumulate as a radio business owner...radio business guys become hoarders of spare parts..every radio guy I know is the same

 

So starting the throwing out process today and will get the wings off the trailer and find a place for them. I will pull the motor out and take the tailplane and fin off then I can easily handle the fuselage then. Got to build another work table for it and do the cleaning up so this is my job for the next week. I am on holidays now for 3 weeks but will be away up at my farm after xmas for a week or so. I am really looking forward to this project

 

Mark

 

 

[rmorton]

 

 

 

[Kyle Communications]

hahahahah thats nothing...I will take a picture of mine and embarrass myself

 

 

[Kyle Communications]

Looks like just enough room to build a Sav though

 

 

[Kyle Communications]

This is my shed 5 years ago when I built mine.. its a lot different now :(

 

 

 

 

[Kyle Communications]

My mess I MUST clean up. Its called once you have more room its a chance to store more crap

 

 

 

 

 

[rmorton]

HAHA youve more to do than me!! much more room than I have though, spent most of my time moving the same stuff from one side of the garage to the other to tile the floor, which is now almost done bar some grouting.

 

 

[IBob]

Hi BobI spoke with the owner about the crash and it seems when he took off he peeled around fairly quick to the left just after takeoff on his homestead strip and wind shear...probably a big tailwind burst arrived and the aircraft then dropped out of the air with the left tip hitting the ground the tail then hit and then the right tip hit then the nose came down and broke the prop and bent the nose leg sideways. The cowl only has a very small smack on it underneath which will take about 30 mins to fix. He also said he could not believe when he got out and looked himself over that he pretty much didnt have a scratch on himself. The complete centre cockpit looks fully intact and no damage at all and not bent in any way. He said the strength of the aircraft and how the cabin protected him was amazing.

 

I think it actually looks worse than it really is. I built my XL in my big garage and even full assembled it in there to set all the angles of the struts and surfaces. Over time though I have accumulated much more "crap" also the mother in law now lives in a granny flat that was built in the back yard so a lot of her stuff is stored in my garage so all of that will have to go back into her shipping container which I have to rearrange to fit all of that stuff into and I just have to bite the bullet and get rid of all the stuff you accumulate as a radio business owner...radio business guys become hoarders of spare parts..every radio guy I know is the same

 

So starting the throwing out process today and will get the wings off the trailer and find a place for them. I will pull the motor out and take the tailplane and fin off then I can easily handle the fuselage then. Got to build another work table for it and do the cleaning up so this is my job for the next week. I am on holidays now for 3 weeks but will be away up at my farm after xmas for a week or so. I am really looking forward to this project

 

Mark

Thanks for the explanation, Mark.

 

I was trying to figure out how he got both wingtips like that.

 

You'd have to hit awful hard to fold the struts, which would then imply main UC and central fuse damage, so doesn't fit with the UC and fuse condition in the pics.

 

During my time in Oz, (70s) it impressed me that any parachute malfunction had the whole drop zone trouping out to where the offending canopy fell, with a group attempt to figure out what had happened.

 

I never saw that in any other country.

 

 

[Kyle Communications]

The U/C you see is a spare new one he put on there so he could keep it on the wheels so I got that as well. The original is bent on the right hand side. I have it here with me so that took the brunt of the third hit with the right side wing tip. The 4 wing struts are straight no sign of bending at all but need a much better look. Flaperons are bent as well but again not really a big deal. Realistically its not that badly damaged. I just got it off the trailer and put it back on that new U/C so I can wheel it around. I have had a look in the back and its what I expected. New longerons and 3 frames possibly 4 in the rear then new sheeting on the rear. I can easily fix the rudder. The fin and stab are fine although obviously I will be checking them. The complete cockpit assembly module both internal and external is pristine and no evidence of stress but once the back comes off I will be able to see more

 

 

 

 

 

 

[IBob]

Looks to be a really interesting project, and probably very worthwhile, given your fabrication facilities.

 

One area that continues to intrigue me in the design is the fuel tanks central supports:

 

Obviously they don't fall out due to impact or heavy landings, or we'd know all about it by now. But there seems to be not a lot holding them in!

 

 

[Kyle Communications]

There is a bracket on each side at the front of the tanks anchored under the wing sheeting and a flat plate about 100mm wide supporting the weight of each tank that goes across the whole tank

 

 

[IBob]

There is a bracket on each side at the front of the tanks anchored under the wing sheeting and a flat plate about 100mm wide supporting the weight of each tank that goes across the whole tank

It is the flat plates across the centre of the tanks I was referring to: at one end they sit on top of a rib flange, which is fine, but at the other they go between flange and wing sheet, and are effectively held up by 3 rivets (or a rivet and 2 small screws, if your cover is screwed on).

 

 

 

 

[Kyle Communications]

Thats all correct. My covers are all screwed in as I put rivnuts around the covers section. But there is no drama with them holding any weight

 

 

[eightyknots]

You've taken on a big project Mark.

 

Just one niggling thought: the Savannah is a monocoque construction. When you change the thickness of some panels, it may transmit forces and stresses to other parts of the plane rather than rely on a certain amount of controlled flexing to absorb these forces.

 

How have you engineered the extra thickness in some panels? Are you trying to overcome known issues??

 

 

[Kyle Communications]

Changing from 0.016 to 0.020 side panels on the fuselage will not change any load factors just slightly stiffen the sideways movement on the rear section. The top, bottom and curved sides remain 0.016 to make it easier to curve those 4 panels. The top and bottom rear sheets are relatively small so have a smaller flex area. The larger side panels will make this a bit stronger overall. The wing skins can only make the wings stronger as the way they are constructed the spar takes the load. The thicker wing skins will stop the distortion in the sun that all Savannahs have here. You can stand next to literally any savannah here on a 30 plus deg day and it will go BANG as the sheets move. Again it will just make the skins stronger. You have to remember its only 0.004 thickness different which is very little in weight but quite a lot in strength. I dont believe it will change the load factors at all over the airframe the only reason the 0.016 was used is to try to crib every bit of weight out of the aircraft. Remember in Europe they are limited to 450kg MTOW we have 600kg.

 

 

[Kyle Communications]

After sitting outside in the carport for the past week Mabel has moved into my shed. I finally shifted enough crap and loaded a heap into my big van ready for another dump run. Here in Brisbane we have been getting some big storms lately and we are off in 2 days up to the farm for a week or so and I didnt want to leave her lashed to the carport. No she is safe and sound in the shed while we are away. I now have the time to get rid of even more crap in the shed so have some breathing space. Got onto a local contact for some sheet 0.020 sheet for the new skins thanks to Danny so I bought all he had which was only 7 sheets and got them for a bargin price and this would have been a fairly major expense for the project just to get the sheets and the freight up from sydney

[Paul davenport]

I will follow with interest, to see how you repair it . Compared to a new build what would be the time and monetary input . Please lots of pictures to show build and repair

 

 

[Kyle Communications]

Hi Paul

 

I will know a lot more once I get most of the fuse apart but it will need 3 internal frames from what I can see. I could make them but its easier to get them from the factory. All the sheets around the rear I will finish drawing and then supply the bare sheet to the laser cutter and get them cut...this will look exactly like and fit exactly like the factory supplied sheets in the kit, the longerons around the rear I can just cut and bend into the shape in the V bender at work. It needs a new rudder post but I can fabricate that and can also fabricate the rudder ribs. I am lucky I have access to a CNC V bender and a nice large hydraulic guillotine where I work so its easy for me to do this. We also have a punch so if I was real keen I could make up a punch set and actually make the internal frames but I am not that keen its cheaper to order the factory parts. The front Omega will need replacing and again I will draw it up and get it cut. I already have access to a new noseleg and I can draw up the front brackets and again get them lasercut. Laser cutting what I can and supplying the material is far cheaper for these larger parts.

 

The wings most of the ribs are ok and with a bit of a further look maybe the spars maybe ok I will just need to draw up the outer extension parts and get them cut. I have access to a few spare ribs if any are bent too far. The sheets I have already now and got them even cheaper than I budgeted for and these will fit just like as it it went together in the kit. The tail feathers and wings took me a total of about 40 hrs to put together from scratch when I built the XL. The flaperons will need new skins which again is really only an hour or so to measure and draw up. I can fold the edges at work. I will need new rear wing spars but again I can just fold them up at work The cowl has only a little work to reglass it. The engine I am getting it gone right over even if it costs me 1K or so to get inspected and bearings replaced is allowed for.

 

To build my XL it took me around 300 hours. I expect this will soak up around 100 hours to get flying again and I hope to get it all done for a total of 7 to 10K including the paint. I have to order some more 6061T6 from down south for the rear wing spars and the rudder post. I am looking at replacing the 8 flaperon hanger brackets and bearings. I may order there from the factory yet I havent decided

 

I have the full build manual for the S it came with the aircraft and all log and maintenance books. This aircraft is complete with all instruments and radios so really nothing to buy there. I will sell my XL when this one is ready but I will fit my twin stick version into the S and I will change over the dash. So the S will have my current XL dash in it and the dash in this S will go into my XL. My XL is all wired in tefzel not that crappy auto wire supplied in the kit either. I have a couple of people interested in the XL now but have been asked to leave my twin sticks in which I will and I will fit another system which I get from the factory into the S with my removeable stick mods. Also of course my special flap brackets

 

Mark