Kyle Communications

The reason they backfire Bob is is a couple of them. The main one is tecnique and also if the aircraft has a aircraft keytype switch fitted which is used for magnetos NOT CDI. CDI need the 2 separate switches. The reason they backfire is the prop/engine is turning too slow when spark is applied , heavy props and spacers also make ths problem worse. This is why separate switches are better. With the switches off you spin the engine with the starter and you will usually hear the spinning RPM go up after a few seconds of spinning this is when you turn 1 switch on then once it fires and ramps up towards idle then just flick the other switch on. This also tests your CDI if you alternate the switch to start each time you start the engine. When you just click on both switches first or use the aircraft keytype switch which essentially does the same thing then because the CDI will start to send a spark at about 150 RPM the engine is under heavy prop load and only just getting to start level in spark and with extra fuel in there from the choke the engine can easily backfire. When you spin the engine up first without any ignition switch on the engine has a chance to get to 200 or so RPM possibly more with a lighter prop combination and the inertial then helps stop any backfire when you hit the ignition. Other factors like crappy earths from the battery to the engine block or small DC cables from the battery to the engine dont help the process either. I was shocked when I first got into these aircraft that so many just earth at the battery and let a riveted alu frame pass the negative to the engine block. Not running a earth directly from the battery as well as the one to the frame to the engine block is just wrong.

I thought it was 2 deg from the original. I am sure I read that somewhere. This just means the engine fires 2 deg earlier than the original flywheel. Whether that actually makes the ignition point any better to stop backfiring I am not sure but it didnt seem to when I did some testing on 2 engines. All the softstart does is hold the engine from changing from full retard to full advance by 6 seconds. When the engine changes it is basically just like you turn a switch on and off. One moment it is full retard then immediately it changes to full advance...nothing in between. It doesnt ramp or do anything just a direct switch. I will do a video and show you. I think I may have a old module here I can show you. The old original modules used to switch over at around 1050 rpm when they had the old switching output devices. When the later version modules came out they changed to a different output device and this shifted the change back to around 800 rpm. I use a different device in my modules which are a higher voltage and higher current rating but they do the change at the 800 rpm as well. I set my modules to hold the engine in retard after start for 2 sec and not 6 sec lie the originals

it shifts it 2deg but thats what I mean..I dont believe it makes any difference due to the way the modules work. When starting the modules are full retard. They do not change to full advance until around 800 rpm..the engine isnt even running by then it wont even idle until about 1400 rpm. So just putting sofstart modules in with a older flywheel will really do nothing. The original softstart. modules hold the engine in full retard for about 6 sec at idle...really a waste of time and the engine runs like aa hairy goat for 6 sec. if you have a neww flywheel well yes the engine will fire 2 deg earlier but really does that make much of a difference????... maybe it does but not that I can perceive..I have done testing. By starting the engine in a certain way you will limit any backfiring anyway. You have to remember these are CDI NOT magnetos

And a new flywheel too Bob...I personally dont believe there is really any difference between softstart and not..its the way you start the engine is the main thing. I have my modules on my engines but havent wired up the softstart as I never get any bacfires

Rodger made it up when he did his wings had it stored here for about a year. So I got the hand me down 🙂 ...I also got Gregs 2 benches he made for assembling his S-21.... bargain bonaza . makes life much easier

Major step number 1...first wing is now down at the hangar. The Mistress left wing is now keeping Mabel's parts company

both are out of the ballpark expensive..thats why I went with MGL. Had great service from the different MGL EFIS I have used over the last 12 years..and half the price or even less

09/08/23 Installed fuel tank stand and filler flange. Installed fuel tank retention brackets. Modified sight tube fitting penetrations and installed LH wing root rib. LH wing fabrication complete. 5.2h

08/08/23 Fabricated fuel cap retainer ring. Marked and cut openings in fuel tank. Vacuumed and flushed fuel tank, checked for leaks under low head. Installed fuel sight gauge and tank flange fittings to tanks. 5.1h

07/08/23 Proseal bonded Viton fuel tank scupper plate to inside of upper RH wing skin. 1.3h

This tragic accident is like most accidents. It is a accumulation of circumstances The ABC report above is pretty accurate but there are a few details that are not stated that did have a large contributing factor on the accident. I have seen all the video as I did the download of all angles for the police and ATSB. It is quite clear what has happened. Luckily we have a good 24/7 camera system at YCAB showing all directions and majority of runways and off areas. I obviously can not comment on the exact circumstances but this tragic situation is a lesson for everyone. We will be looking into a permanent radio recording setup for the future. I made a system that I used here to monitor all radio calls around the airfield for about 3 months and considering I am 7km away from the airfield it did work very well. I will be pushing for a more professional system to be installed at the airfield.

Havent magaged to get a lot of work done on Mabel lately..its been too cold at night out in the shed and have been up at the farm for 4 days every 2 weeks trying to get the house finished. Finally today got to work on her. Grabbed the parachute box I made...so long ago it seems now and got it installed. Had to get the mrs to give me a hand lowering the chute into the ammo box and got it all mounted. Not sure how I am going to run the trigger for it yet or where I will mount it. I think I will cover the box with very light carpet because it will be easy to d that rather than waiting for paint to dry. Up the farm again next weekend but the following week I hope to get Mabel down to the hangar

RGMWA. well it helps when you have a second person helping doing the build. Still a lot to do. Another wing yet and the tail feathers..and they are quite big. But there is a stack of work in the fuselage. Even though it has a prewelded metal cabin cage the whole structure in the rest is quite complex and certainly very strong as well. Rudder cabling and controls are more complex as well.

Very different to a savannah kit. Certainly a lot stronger in build. Also a lot more work as holes are not to size. They are match drilled but you have to redrill them to the correct size. Not fussed on the rivets though they are cherry style. I much prefer the Avex style of rivets

17/07/23 Riveted lower LH wing skin to ribs. Match driller rear spar, deburred, vacuumed swarf from wing cavity and riveted skin to rear spar. 6.8h

Savannah builders will recognise the dreaded black goop. It is actually a fantastic product if applied correctly. Its not put on everywhere on this build as I havent put it on every mating surface. Only the surfaces that may have moisture ingress like the skins and rivets. I got a couple of tins from Aerokits just for this project

Yes Nev the S-21 is more like a GA aircraft in build. Mine will be in Group G 760kg category or if CASA get their sh*t together with their medical I may put it into VH Experimental. The limit at the moment is the S-21 with a Rotax 100hp is limited to 727kg MTOW but with a Titan or similar it is 820kg MTOW. So the airframe is limited by the manufacturer by horsepower. My Rotax is 114hp so my weight could come up a little to probably 750kg. The empty weight for most seems to be between 370kg and 400kg with a Rotax engine and about another 36kg heavier with the Titan

12/07/23 Removed lower LH wing skin and deburred leading edge spar. Roller applied two coats of corrosion inhibitor to spars, ribs, stringers and tank supports. 2.9h

All 4 major ateries were blocked but they only bypassed 3 large ones I have had a cardiac 3D ultrasound before but it doesnt tell how the chambers are operating with atrial fibulation and flow in the grafts My heart showing the grafts about 18 months after the op

Actually the std stress test is 7 mins..you can go longer if you want to. I dont have a lot of faith in them after my experience. Angiogram is the best test but that is very invasive This cardiac perfusion test is the next best apparently and not so invasive. There are 2 tests done on the same day over about 5 hours or across 2 days. Mine is the one day. One is they inject you with contrast while you are resting then they do the MRI. The after that you have to twiddle your thumbs for a few hours then they inject a small dose into you again and you get on the treadmill for a stress test to bring the heart up to 85% max and when you are finished they get you in the MRI straight away then hit you with a bigger dose of contrast then image that. They basically compare the resting film with the stress film and they can see what areas are not flowing or pumping correctly also any blockages or even slack chamber pressures etc.. So I will find out tomorrow I suppose

That Zongo engine isnt that cheap anyway...I spoke to them when they popped their head up a few years ago. At the time I think the Rotax was about 28k but the zongo was about 22k...so it wasnt that advantageous to try on a risk

When you do a test there is a nurse and a doctor and another person. You are well monitored well at my cardiologist you are. My one last year I asked how it was and the doctor said..who by the way was same one that did my last one said..."its a carbon copy of the one done in 2018"...so all seems to be ok. But this perfusion test is just for my own peace of mind to make sure as a stress test doesnt actually tell you if there is a real problem. I had a stress test back in 2012 and all was fine so they told me..then 6 months later I am on the table with 4 arteries 90% blocked 3 days after the angiogram

Glen thats easy yes. But I have a Heavy vehicle licence with conditions. Yet I can drive a 64 tonne BDouble through a major city but they say I cant fly any aircraft with 1 pax up to 1500kg. I have a full dual timeslot medical every year from my GP to satisfy the Austroads licence to maintain my heavy vehicle licence AND I have a yearly appointment with a cardiologist and usually a cardiac echo or like last year a stress test and as a matter of fact I am having a cardiac perfusion test this thursday. Realistically I have a far better idea on how I am going than most people flying rec or even VH rec aircraft. Most never know what their bodies are like and what condition. They could drop dead at a pinch and some do. All this costs me about $1000 per year..yet I cant fly a aircraft up to 1500kg and 1 pax according to CASA My DAME signed me off for a Basic Class 2 a few of years ago as he was happy with all my blood tests and also all my results of my ticker. I need to go back and see if I can get it again as it has lapsed but I am hearing CASA would reject it even though it is the DAME's decision

I just registered for it...I want to hear what they say and I am going to hit them up with some real world facts and see what they say