Another NEW Savannah XL on its way

[Kyle Communications]

Started my new dash installation this week. Pulled out the old dash plate and soon created a huge mess on the floor with wiring and switches. I will post some pics soon of the new dash now I have the other Xtreme out. I also made some new temp sensors for the RDAC so they actually fit a Rotax and played with all the connections and simulated the rev input from the engine. All seems to work great on the bench. I hope to wire it all at home and basically just plug the dash into the main harnesses. Crossing fingers it will be all reinstalled by the end of next weekend.

 

On another footnote the dual stick installation I did is just fantastic. Flew out to Inglewood fly-in 2 weekends ago and flying in big winds so it was slow on the way out and back. 2hrs 10 mins I have never been able to fly that long before without my bum wanting to separate from my body due to having my leg twisted to use the centre stick. After this time in the seat I had no pain what so ever so long trips are now on the cards. Look out Steve.

 

Had a fuel issue on the way back where my outer right tank would not drain so I made a stop in at Watts bridge with very little fuel left to see if I could find the problem. Turned out to be a little insect had blocked the breather tube, mine is setup as per factory with the 3mm tube going through the wings. I managed to release all that fuel back into the other tanks and flew back to Ycab no issues although it took almost 45 mins the wind was really strong. I got some 1/4 stainless tube which I put 1/4 UNF threads onto then 2 nylocks back to back and put those into the caps. All 4 tanks have now been done I will post some pics tomorrow as I am away up at the farm this weekend

 

Mark

 

 

[rankamateur]

Look out Steve.

Bring it on, Bring your mates! We will call it the Savannah Muster.

 

Have I heard of that before?

 

 

[Kyle Communications]

Here is a couple of pictures of the new dash. The blank hole is for my radio which is still in the plane.

 

 

 

 

[Kyle Communications]

There a still a few bits to put into the dash like the trim display the fuel reserve test sw and flashing LED. The blank area under the EKP-V on the right is for expansion of small guages or other accessories

 

 

[Guy s]

Looks great Mark, I'm not sure what to do with my dash yet and will give you a ring when I get closer to that stage and pick your brains.

 

 

[Kyle Communications]

Yes its a Ipad Mini in a AirGizmo dash mount.

 

 

[Kyle Communications]

Here is the new breather tubes which just go direct into the top of the fuel caps. 1/4 inch stainless tube with a 1/4 UNF thread run over the tube.

 

 

 

 

[eightyknots]

Here is the new breather tubes which just go direct into the top of the fuel caps. 1/4 inch stainless tube with a 1/4 UNF thread run over the tube.[ATTACH=full]36462[/ATTACH] [ATTACH=full]36463[/ATTACH]

How will that prevent insects from blocking the air vent?

 

 

[Kyle Communications]

The internal hole is much larger on the SS tube and I will fold up metal gauze like flyscreen and put it into the tubes this will stop anything going inside and should not block the airflow. The problem with the standard Sav system is the 3mm tube the hole size in that tube is around 2mm or slightly smaller so it doesnt take much of anything to block the hole.

 

 

[Kyle Communications]

Now the new dash is in and working great...the next project.

 

You may have read the thread wanting a rotax muffler ..this was all due to going for a fly in Graham's new tecnam and noting it had heaps more grunt than the sav from a stand still and we have the same props. On investigation the small ICP muffler is heaps smaller in volume than the genuine rotax one,around 1/3 less also the rear exhausts hit a wall about 30mm from where they go into the muffler so this will be choking the engine for sure.

 

So the plan was to get a old rotax muffler and see what could be done...couldnt seem to find one so I got a new secondhand one and looked inside and roughly saw how it was made inside....very surprising I thought there would be much more too it. I took it into work today and cut off the side I thought would be the easiest and the pictures attached are what is inside. This will make it very easy to fit now. The sav's engine bay and mount restrict where the rear engine pipes can go. The rotax muffler is around 5 inches short so I plan to roll up a piece of 1.5mm SS sheet and fit it in between the area I just separated. This will allow me to go straight onto the 2 rear engine pipes and it will be much easier then to make up the new front pipes as they come in at a more 90 deg angle on the rotax muffler.

 

 

 

 

 

 

 

 

 

 

[Guy s]

I'll be interested in what you think of the end result Mark and if you found it worth while doing the mod. I wonder why the ICP muffler is smaller than the Rotax muffler and I'm guessing to fit inside the cowl ? I haven't got up to that stage of my built yet and am just curious.

 

 

[Kyle Communications]

Hi Guy

 

The ICP one is just that reason. To fit inside the cowl the later ones I am told are even smaller to stop the cowl getting burnt by the ends of the muffler. I have holes cut in my cowl to stop that problem. I will run the engine up at full power with the old muffler system and see what the rpm is then change over the muffler to the rotax one and do the same test. This will tell me if it does produce more power. I expect to see maybe 200 or 300 rev improvement at the same pitch.

 

 

[Geoff13]

Put a scale on it and see and measure the thrust before and after.

 

 

[eightyknots]

Now the new dash is in and working great...the next project.You may have read the thread wanting a rotax muffler ..this was all due to going for a fly in Graham's new tecnam and noting it had heaps more grunt than the sav from a stand still and we have the same props. On investigation the small ICP muffler is heaps smaller in volume than the genuine rotax one,around 1/3 less also the rear exhausts hit a wall about 30mm from where they go into the muffler so this will be choking the engine for sure.

 

So the plan was to get a old rotax muffler and see what could be done...couldnt seem to find one so I got a new secondhand one and looked inside and roughly saw how it was made inside....very surprising I thought there would be much more too it. I took it into work today and cut off the side I thought would be the easiest and the pictures attached are what is inside. This will make it very easy to fit now. The sav's engine bay and mount restrict where the rear engine pipes can go. The rotax muffler is around 5 inches short so I plan to roll up a piece of 1.5mm SS sheet and fit it in between the area I just separated. This will allow me to go straight onto the 2 rear engine pipes and it will be much easier then to make up the new front pipes as they come in at a more 90 deg angle on the rotax muffler.

 

[ATTACH=full]37519[/ATTACH] [ATTACH=full]37520[/ATTACH] [ATTACH=full]37521[/ATTACH] [ATTACH=full]37522[/ATTACH] [ATTACH=full]37523[/ATTACH] [ATTACH=full]37524[/ATTACH] [ATTACH=full]37525[/ATTACH] [ATTACH=full]37526[/ATTACH]

Rotax's is a pretty simple muffler from the look of it. The problem is, where are you going to house the larger Rotax-style muffler?

 

 

[Kyle Communications]

If it gives me more HP then I will just modify the cowl. Its no issue really just need to cut off the bottom fence and then graft it further forward. The rotax muffler will hang a little lower of course but shouldnt be any drama. I am going to get all the measuring done tomorrow and I will take some pics this weekend. Once I make the jig to hold the muffler in the right place I can cut and fit the 1.5mm stainless sheet and then roll it and it will be welded while it sits in the jig to keep the distance correct for the 2 rear pipes.

 

 

[rankamateur]

Be aware that the reason that the performance of the Savannah VG is so similar to the Savannah XL/S is that the added lift/reduced drag of the streamlined cowl is approximately the same as the added drag of pushing the 5 inch broader fuselage through the air. Be careful you don't use all your extra power overcoming extra drag.

 

 

[Kyle Communications]

It isnt that streamlined with the big drag plate underneath in front of the existing muffler. I will be just shifting it further forward a few inches there will be no change to the width of the bottom. The rotax muffler is 5 inches shorter in width than the iCP one it will hang down a bit further but not that much and its round anyway so should creat any real extra drag.....hey there maybe no difference after all of this but if I can get a bit more grunt for takeoff I will be happy

 

 

[rankamateur]

Won't be so much drag at take off speed, cruise is where it will bite you harder.

 

 

[Kyle Communications]

Steve around end of sept or mid october I might be flying down to Gunnedah to look at a Rans S20 Raven kit. You are not far off track so hopefully will drop in for a visit

 

 

[rankamateur]

Let me know what I can do to help.

 

 

[Geoff13]

Do you have a scale to measure the thrust tomorrow Mark?

 

I will be out there tomorrow, been working all week and tomorrow I want to extend my pitot tube forward of the leading edge and relocate the static. See if that can improve things. Dropping my Son at the airport at 0500 so will probably have about 5 hours up before you surface. LOL

 

 

[eightyknots]

It isnt that streamlined with the big drag plate underneath in front of the existing muffler. I will be just shifting it further forward a few inches there will be no change to the width of the bottom. The rotax muffler is 5 inches shorter in width than the iCP one it will hang down a bit further but not that much and its round anyway so should creat any real extra drag.....hey there maybe no difference after all of this but if I can get a bit more grunt for takeoff I will be happy

I have always wondered about why planes (including the Sav) have a fence. It looks like it introduces unnecessary drag. What would be the implications of reducing the height of this, or removing it altogether?

 

 

[eightyknots]

If it gives me more HP then I will just modify the cowl. Its no issue really just need to cut off the bottom fence and then graft it further forward. The rotax muffler will hang a little lower of course but shouldnt be any drama. I am going to get all the measuring done tomorrow and I will take some pics this weekend. Once I make the jig to hold the muffler in the right place I can cut and fit the 1.5mm stainless sheet and then roll it and it will be welded while it sits in the jig to keep the distance correct for the 2 rear pipes.

It will be interesting to see whether the muffler swap will give you a few extra horses under the cowl. Only a scale will measure this objectively, as Geoff13 suggested.

 

 

[Geoff13]

I have always wondered about why planes (including the Sav) have a fence. It looks like it introduces unnecessary drag. What would be the implications of reducing the height of this, or removing it altogether?

Don't shoot me down if I am wrong because I am certainly not an aeronautical engineer, but I assume that it is to create a low pressure area below and behind the engine bay to draw the air through the bay. Without that I suspect that the air coming in the front would hit the firewall and create a high pressure area that would prevent good airflow.

 

 

[Kyle Communications]

I will do it when I have finished modifying the muffler as I want to do the test on the same day only a hour or 2 apart. Just the engine rpm will tell as well. If I can turn the prop 200 or 300 rpm more with the same prop and pitch this has to mean more horsepower. Then you can increase the pitch a bit to drop the rpm back to what mine is set for which is 5250 to 5300 at full power on the ground. This gives me around 5250 on climb at 6o kts. Full power straight and level is 5600 rpm this returns around 95 knots. I dont necessarily want higher cruise speed it would only be another 2 knots or so. I want the extra grunt on takeoff for getting off the ground quick