Discussion in 'Other Rec Aircraft' started by Geoff13, Sep 7, 2014.
I hope you will be able to move it forward to completion before long!
You bet! But it has to be checked and re-checked until totally happy with it.
We wouldn't want it any other way.
Only then can the cork go "pop", and the smile of satisfaction get even bigger.
Can't wait to see all the photo's.
So I made my lists. List 1 had 31 items on it. I have been full noise at it since making my lists up. As I said started with 31 items, added another 15 or so along the way. I spent most of today chasing a fault that was totally in my own imagination. I primed the oil system and when turning the motor over I was not getting enough oil pressure. After about 4 hours I gave up and rang my L2 mate, he assures me that considering the number of Revs the reading that I had was enough to give it a run. Feeling just a little bit excited, a whole heap of terrified and a fair amount of trepidation, but failing rain or hail, tomorrow morning I intend to give her a run. Not a lot just enough to check that the engine instruments all work and temps and pressures get into a good spot within a reasonable time frame.
A sneek peek at the work done to the cowl for those who are interested. It cost me a mortage on my first born but to be honest, I think it was a fair trade. LOL.
As you can see the list is still stuck to the windscreen. Thank you for that bit of advice Jim
Looks great Geoff.
Enjoy the runup tomorrow.
Good luck with the start up mate, I hope it all goes well for you..
I hope it goes well for you!
Well that did not end well.
How did it go Geoff? Not good?
Well the motor started (Just).
Once we got it running everything seemed good temps ok, oil pressure ok, charging, gauges all working but a possible problem with the tacho. The carbies will need balancing obviously but in light of the fact that engine needs to come back out that little task can wait. It seems that wi have a stuffed Sprag Clutch. During my due diligence I found that the Sprag Clutch had been replace 300 hours back so didn't inspect or have that inspected before going ahead. We rebuild the gearbox and the carbies but decided to leave the back end alone. So I suppose that was a bad decision even though I still think that I made it for the right reasons. So tomorrow it comes out again and we pull the back end of and make a new list of parts.
That is a bit sad Geoff. I hope you are able to get it all sorted without costing you an arm and a leg.
Its not so bad Eighty Knots. At the end of the day, it is just a Sprag Clutch and associated parts. It was more the disappointment than anything else. At the end of the day I made the decision to not look in that part of the motor based on the info available and it turned out to be the wrong one. But it never hurt anyone other than my patience and my drive and really they will all come back. So now the motor is out and on the bench and now just waiting on people with more knowledge than me about these things to come up with a shopping list so I can get the parts and start heading back in the right direction again. No harm done, no pain suffered and a little bit more waiting.
Gee am I pissed off. I knew that there was one factory built X-Air Hanuman in Australia when I was looking at planes. I actually went looking for this plane and couldn't find it. I could have waited 6 months, bought it tomorrow and flown it home and still have been in the air sooner than I will with mine. And it is factory built to boot. Boy am I tempted to just go buy it and sell mine.
But then as I always say I guess being pissed off is better than being pissed on
It took me about 4 hours to take the motor out. 3 weeks to get the parts and rebuild the Sprag Clutch. We rebuilt the water pump and checked out the starter at the same time. I must say that the guy I bought the motor off was a perfect Gentleman. Even though I bought a second hand motor he immediatly offered to pay for the parts for the sprag clutch. So 3 weeks to do the motor, then a death in the family and having to move house further delayed things, so it wasn't until last Thursday that I managed to get back to the plane. I expected to take at least a week to get back to where it was but I misjudged my own experience at putting this motor in. I have after all had it in and out at various levels 5 or 6 times now. By Friday night it was in and I could have test run it. I decided to leave it until Saturday to give myself Friday night to think about it all and then Saturday morning to give it the once over.
Saturday was a glorious day. Up bright and early a drive up to the field and a few hours of checking, rechecking and checking once again. Then it was time to bite the bullet and drag it out, tie it to the back of the ute and press the button. Well again not the result that I hoped for cranked it over and nothing. I did this two or three times and still nothing. So I sat back to contemplate my navel. As I looked down a the aforementioned navel I spotted a big red handle pointing across the cockpit. Of course I had decided after my fire scare that I wanted a fuel tap easily accessable so I spent days building and fitting one. Maybe I should turn that red handle and see what happens I thought. Well that had the desired effect. Push the big button again and we got the expected noise and wind coming from up front. What a relief.
The motor stopped and started as required even though it did sound a bit like a VW. I had been told that it could sound like that if it wasn't balanced right so I wasn't to worried. The tacho was giving some funny results, it was jumping between spots rather than a smooth flow. And water temp was reading high. Ok very high. I knew the water reading was incorrect as with a reading of 100 to 110c I could still comfortably hold the header tank and/or both radiator tanks in my bare hands. Ok little things I thought I can fix that.
I made the required texts and phone calls to all those people who were waiting to hear the results. Jim offered to come down Sat arvo and balance the carbies for me. There are tasks that are beyond my abilities and I am more than happy to hand over to people more experienced than me. So now with the carbies balanced she sounds as sweet as any Rotax I have heard.
I spent yesterday and today tracking and fixing the tacho problem( my fault I didn't earth the sender) and the water temp which was a mismatched sender unit to the gauge. Note to self do not hook up a cheap gauge to a VDO sender, only use a VDO gauge.
So with all that done and about one hours running behind us tomorrow and Thursday to tidy up some loose ends and then Thursday night we do the W&B. I do not anticipate any problems but there is a possibility that I may need to relocate the battery. I hope that is not needed for two reasons. It is suggested to fit it under the passenger seat which I think would detract from the safety area under that seat for the pax in a extreme heavy landing. Also after my smoke experience, the less electrical cables needed to run through the cockpit, the happier I will be. So the battery stays engine side of firewall unless it fails the W&B.
Then all that should be left is for the test pilot to do his checks of my work and then wait for the right wind and a time when he can fit it in and see how it all goes. Fingers crossed we may even get to see daylight under the wheels by this weekend. . Maybe
Getting closer. Tyre pressures today. Taxi run but I really need to adjust those brakes. On the runup pad with the J motor at 3000 rpm no problem brakes held fine. Same pad today 3000 rpm with the big prop and she beat the brakes quite easily. Looks like a bit of work to do there. Still and all my to do list is now down to single digits. Tomorrow is a full power run before we do the W&B. That could be interesting. I copied the pitch of the prop from a friends Savanah with the same prop minus the winglets. With a bit more homework today it appears that the winglets on my prop may give a distinct advantage over a similar prop without the winglets. Maybe a bit more homework to be done there. So the list is short but the potential for research really does just keep getting longer and longer. Is it really over 6 months since I started this. It has been one hell of a learning curve by anyone's standards. I regret not measuring the thrust before removing the J motor but to be honest I didn't even know that was possible back then. Will be interesting to see what that is now. I did at least get a BEW before the conversion so at least next time someone asks me what the weight penalty is I will be able to give an informed answer. There are so many things that I should have checked before starting but as they say we really do not know what we do not know.
How did your W&B go the other day?
That's great Geoff...all systems go then.. Well done..
Great stuff! Now, for the flight report.....
Sorry again for the delay guys but life once again got in the way. Just so busy.
Last Saturday was the test flight. First I had to past the test with the test pilot. We also had to get through a weight and balance.
The test pilot gave me a list on Thursday night. Even I was surprised at how thorough his inspection was. I actually had set the goal of not allowing him to find anything. To my surprise, he found several things. I was not worried about most of them as I had not finished of one area because I was waiting to see if the battery had to be moved. On paper the battery is fine forward of the firewall. The plane passed all the W&B checks with it located in the same position that it was before the change. For anyone interested, the weight penalty for the Rotax 912ULS, over a jab 4 cylinder came in at exactly 16 Kgs. It is a question that until about midnight Thursday night had not been able to be answered by anyone. Even talking to Bert Flood guys got me an estimate of about 10 kgs. I doubled that and allowed myself up to 20 kgs to still make the plane usable for myself and my wife. So at 16 Kgs it was within my initial estimates. With the weight that I have put on during the project with my wife and I onboard, we can go with 70 litres of fuel.
By the time we got to the test flight, I had run up 1.8 hours on the motor with it tied to the back of my ute on the ground. 6 minutes of that had been 2 stints of 3 minutes at WOT. 100HP WOT tied to the ute. For me that was about a scary as it can get, especially when the nose wheel spring compresses at 4200 rpm and the nose drops by 4 inches. I have to say the first time it happened I crapped myself. Note to self ensure you lock the canopy of ute down before trying this at home. Imagine my surprise when after the first power run I got out of the plane and realised that the lid of the ute was up. No damage but an important lesson. So all the ground runs were good, the W&B was good the last minute jobs were finished and signed off. The test pilot had told me 6 months ago that he would only fly it if it was runway 12 or 06 so that he had a choice of paddocks.
Saturday morning. No wind which means runway 12 is the go. I was at the hangar at about 0400 for the 3rd morning in a row. finish off as much as I could then wait to see if Jim was willing to take her out. Well he arrived, checked my work modified a couple of things for me and in what seemed like no time at all, I was standing under the windsock watching my plane taxi down to the runup pad on 12. With nerves at level 101 I watched with no possibility of any input for the next 45 minutes. I had my video camera and my mobile phone with me. It was good that I had the phone because I forgot to press the button on the camera.
So my 3 week job that took a shade over 6 months had come down to this. watching someone else (who I will admit I trusted implicitly) take my baby and fly away. He warned me before he left that he may go around a few times to get the feel of it. So with runups completed he taxied out onto 12 just as a sling came in and landed. This will become relevant when I post the video later, as every video I got had the sound of a different aircraft in it. When it took of I thought to myself s**t it seems high as he passed overhead, remembering I was only about halfway down the runway. In hindsight there is a very good reason for that, this thing loves to climb.
So he came back 40 minutes later and did a touch and go then a circuit and landed. The three comments that stick with me were in the order I remember them.
1200 feet per minute 1 up at 70 knots.
Its a bit right wing down.
And the ASI is not accurate it can't be stalling at 20 knots.
He was right on all three comments.
So it loves to climb and I am playing with the pitch of the prop to get the best balance but it seems that 1200 per minute at 70 knots is going to be about right. If I pull it back so that it is climbing at 55 knots as per the POH it actually scares me a bit. Lying flat on my back seems unnatural to me. If I do, the figures go north of 1500 per minute.
It is still a bit right wing down, which I don't remember from before the change over so am doing some more homework before I change anything on that.
The ASI was reading low and I am still working on that.
In the past week I have done 10 hours all within glide distance of the airfield or the paddocks just to the south. Everything seems good and I am almost to the point of being willing to take it a bit further afield. The prop pitch still needs work. It is tending to over rev at WOT straight and level. It really does climb like a homesick angel so pitch will not be set to acheive a climb rate but rather to leave a safe gap between cruise speed and Vne, and also ensuring that it can't over rev on WOT, just incase the cables break.
Negatives. There have to be some, and I would be lying if I said there were none.
I do not like the throttle. The positioning and operation are causing me some issues.
I am having trouble landing it. (On a 1300 metre runway on the 2nd attempt I thought that I might need to go over to Brisbane to land.) It is not idling as I would like. On the ground it idles fine but in the air when I pull power it seems to be still revving to high. This in conjunction with the fact that I am not trusting the ASI is causing me some grief. So tomorrows job is to test the ASI and go do some stall testing in various configurations so that I can come up with some realistic landing speeds. Hopefully then, I will be able to land it without having enough runway to land the space shuttle.
In short it is not perfect, but this is a brilliant combination and I am certain the this aircraft was designed with this engine in mind. It has taken me far longer than I had planned, than I wanted, or than I am comfortable with. I am however extremely happy with the results and with the initial testing.
Would I recommend that anyone else try it? Yes.
Would I do it again? On initial testing, yes in a heartbeat.
Regrets. Yes of course. If I had gone with the new Jab or the Camit, I could have been flying 5 months ago so of course I have regrets.
If I had gone with the D Motor, who knows what the results would be. I could now have the only flying D Motor in Australia had I gone that way. Maybe I will build a new one with a D Motor.
In summary. Learning Curve was straight up.
Frustration, almost impossible to describe.
Satisfaction??? Well ask me in 1000 hours, and I will tell you if I made the right choices or not, but on early result I must say, I am one happy camper.
So in the last 6 weeks,we have had the deaths of 2 close family members, the need to move house at extremely short notice, and the completion of the first stage of this project. It has been a roller coaster ride but fun. Now it appears time to start setting some new goals. Photos and Video to follow if I can work out how.
Sounds great Geoff...well done mate.. time now to go out and enjoy your baby..
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