Aircraft in forced landing, Moorabbin

Broken piston return springs (and low on blinker fluid).

 

(I own and operate a Jabiru engine. My piston return springs are A1.)

OK I will bite. What the hell is a piston return spring?

Blinker fluid? I think someone is yanking our chain. Concerning carbie ice. I have seen it said by CASA that carbie ice is most common on take off. I have had it once on a Continental engine in very cold a foggy conditions. Normally I would expect it at reduced throttle on a humid day.

We still don't know what caused this event, but I guess that if it was something that could be caused by Jabiru it would have been spread far and wide by now.

What the hell is a piston return spring?

Yes I realised that hence the ref. to chain yanking. I recall that several cars had to be recalled to have the blinker fluid topped up. It became apparent when fluid only came part way up the glass.

Yes I realised that hence the ref. to chain yanking. I recall that several cars had to be recalled to have the blinker fluid topped up. It became apparent when fluid only came part way up the glass.

If casa says

Concerning carbie ice. I have seen it said by CASA that carbie ice is most common on take off.

(2) Take-Off – Take-offs and full throttle operation should be made with carburetor heat in full cold

position. The possibility of throttle icing at wide throttle openings is very remote, so remote in

fact, that it can be disregarded

I know who I would believe. As per the POH I have never applied carb heat while flying the musketeer (0-320 lyc) and the Thruster has no carb heat, just like a Tecnam I inspected.

If that Jabiru had carb ice no golf course would be safe from falling aircraft.

Piston return springs:

https://www.youtube.com/watch?v=oFX_Xq9WHTI:393

Not sure of the relevance, it wasnt a Lyco? Different carb, even in different location?

 

Jabs common to get ice on taxi and idling in winter inland, rough running on take off would require quick thinking if you werent expecting ice.

 

Pre take off check is apply carb heat, note rpm change

You will lose a lot of power with carb heat applied during takeoff with most engines.. Enough to compromise the take off.. That's why I always check both when going around. Power full open, Carb heat off.. There's nothing to stop you doing a "clear ice" process prior to take off IF you suspect there's even a possibility of it.... The POH is not the maximum you can do. It's for "normal " OPS. We are still having mishandling of engine icing causing engine failures . on carburetter fitted engines.. Not often but enough to keep it in your mind. Nev

We have little idea about this EFATO, that's the point

Re ice, Yep, POH written in Bundaberg Is guess and if youre not expecting it would take quick thinking to clear and keep going.

I regularly clear carb ice before take off in cold weather and its hardly noticable when idling. The carb heat check on run ups (if youre not to fast) will let you know if its there with a rpm RISE.

Jabiru carb heat setup has very little effect on power, esp 3300, and can handle normal operation left on all the time, all the air is filtered on nearly all Jabiru aircraft hot or cold.

I saw a jab abort a touch and go (late) some years ago and spoke to him afterwards. He had left the carb heat on that he applied during the approach. There was no way that plane was going to fly. I don't recall what model it was, but it was a 4 cyl. and didn't have a KFM . Nev

4 cyl are more effected than 3300. not sure why?

There was a 1600 Jab, years ago and it didn't have any spare power. I used it in my Corby for 100 hours, but the leaking oil was too hard to stop and the 2200 was affordable and had ample power.

in my experience, leaving carb heat on during takeoff in a jab LSA/55 (2200 engine) makes no discernible difference. I know this because I've made this mistake. Admittedly I operate on a fairly long strip that's close to sea level.

IF there's no difference the carb heat won't be effective at de icing the carburetor. Nev

Phil . I hope you didn’t forget to shout “ four” ?

I was reminded the other day about Another Golf Course landing, but this time it was deliberate, and planned to avoid any 'Greens' Can't remember the name of the Club, but it was around half way back from FivePee Green to Penkridge, and I was using the auxilliary Belly Tank, having exhausted the rear one. My Mate Steve in the back seat said that the fuel Gauge on the belly tank was reading Zero. . . I decided it would be a good idea to carry out a powered landing and see what was up, we left HG with a full tank, so we must have a serious leak here.

We rolled out almost at the front door of the 19th Hole and found that the spring Clip on the belly tank pickup had fractured, and there was evidence of fuel leaking into the belly fabric of the trike. . . I repaired this with a coupe of Strong zip ties and we were able to continue the arduous 15 minute trip back to base. . .NO, . . we Didn't have a drink first, But we DID get a lift to a local garage to refill the tank ! Where would early microlight aircraft have been without Zip Ties, Duck Tape, string and Velcro. . . ? ?

Oh and btw,. . it's 'FORE' ( No,. . .me neither. . .I've never understood Golf )

IF there's no difference the carb heat won't be effective at de icing the carburetor. Nev

It sure works, even when idling

Carb heat is meant to produce a stipulated temp rise AT the carburetter when applied on certified aircraft. . To do this it would have to degrade power significantly just from the affect of the hot air.. Some also have a completely different path for the heated air and it's often unfiltered. The thought music is better unfiltered than not at all. It would be possible for some of the "forward facing under the prop filters to block with rhime ice or grasshoppers" I suppose. I have used electric heated carbs and it seems to work.. Plenty of older types of engines had no filter at all and some larger ones inject alcohol into the intakes for de icing.. (Radials). I think if you have the possibility of icing with your motor type a carb body temp gauge would be helpful..Nev

I had a Rotax 503 on a cool but very humid day, running at fairly high power for over an hour and when I landed the carbs were glistening with a film of ice, I had no carby heat available then and the engine was running sweetly, didn't falter when reducing power to land. I wonder what carby temperature gauges would have shown as the ice was obviously external.

Quite cold I would expect. There was a view about that premix doesn't freeze but I'm not convinced. The ice might not stick to the surface as much but ………….. Hope and magic shouldn't be relied on. Nev

I had a Rotax 503 on a cool but very humid day, running at fairly high power for over an hour and when I landed the carbs were glistening with a film of ice, I had no carby heat available then and the engine was running sweetly, didn't falter when reducing power to land. I wonder what carby temperature gauges would have shown as the ice was obviously external.

Carb heat is meant to produce a stipulated temp rise AT the carburetter when applied on certified aircraft. . To do this it would have to degrade power significantly just from the affect of the hot air.. Some also have a completely different path for the heated air and it's often unfiltered. The thought music is better unfiltered than not at all. It would be possible for some of the "forward facing under the prop filters to block with rhime ice or grasshoppers" I suppose. I have used electric heated carbs and it seems to work.. Plenty of older types of engines had no filter at all and some larger ones inject alcohol into the intakes for de icing.. (Radials). I think if you have the possibility of icing with your motor type a carb body temp gauge would be helpful..Nev

in my experience, leaving carb heat on during takeoff in a jab LSA/55 (2200 engine) makes no discernible difference. I know this because I've made this mistake. Admittedly I operate on a fairly long strip that's close to sea level.

“makes no discernible difference” .... that may well be correct Cooperplace, particularly in a cooler part of the country, as you are. The carby heat output will be affected by the OAT and, with that temp at say 8 oC, you may get a 10 oC increase with carby heat selected, taking the incoming air temp. to18 oC, which may still be lower than the OAT further North in Summer/Winter which has no discernible affect on Jabiru engine performance. Many variables here .... Bob.

The carby heat output will be affected by the OAT and, with that temp at say 8 oC, you may get a 10 oC increase with carby heat selected, taking the incoming air temp. to18 oC,

That would still leave you in almost prime carb ice territory. As facthunter said there are requirements for certification. The chart says serious icing ANY power for the dark blue, lycoming say somthing different.

Some thread drift here. We don't know why the Jab crashed.