Jethro Belle

The concept it a great contender for a 'safe' Bass Strait crossing, hence my checking. Just Googled it and Jabiru J432, Twin Engine Aircraft seems to be it. One aircraft that caused a big flurry in 2013, but still awaiting South African type certification. It seems an SA build with nothing in Australia yet. A Cri Cri version of the Partenavia P.68 is how I would describe it. Pity the engines need such HUGE cowling as they look ugly and must create 200% form drag IMHO. The performance figures look similar to a standard J430 so you are paying for safety. They claim asymmetrical thrust is not that of a traditional standard twin. I have read about standard twins killing most typical GA pilots within a few minutes of engine failure due to their asymmetric thrust causing it to roll and power spin as I recall. It is really nasty to correct and single engine performance is marginal, so the risk reduction offered by a traditional twin barely outweighs their benefit for GA aircraft, and you pay double the engine bills. Twice as many engine failures! It would be great for Jabiru to make this a success as it would counter engine failure concerns and create its own niche aircraft market. Maybe Jabiru engine failure rates have dropped so a twin is less attractive and they are not pushing it to market. The low engine life many have experienced may count against it given that cost is doubled. I suspect many will not be a enthusiastic about it as me.

Thanks to all for all your risk assesments regarding crossing Bass Straight. Being Tasmania based means getting to things happening on the mainland with your plane leaves you have no choice, and for me flying your own special plane is part of the attraction. For those coming the other way I can see it is a challenge and achievement, like mountain climbing, plus flying your own plane. Buying/Selling planes across the Straight make it inevitable if it is capable. In special jobs where airlines aren't servicing, some people do it to "work commute", I have heard. There are RAA category planes with oxygen fitted capable of flying high enough to make the island hopping route (http://www.recreationalflying.com/threads/crossing-bass-strait.23940/) possible without ever being unable to make land (90% sure, but need to check). I am confident some LSA engines make the category equally reliable and capable as older GA, and don't GA planes make the trip often? I am probably showing my ignorance here, so I expect posts to correct me . At the present I can't see why your (SSCBD) Swiss Risen aircraft, correctly kitted and prepared, could not do it easily. Wouldn't you want to? My risk assessment however may conclude you (SSCBD) are at least partly right and I am worried there is a high risk it will. Has anyone done/aware of an objective risk assessment comparing the Bass Straight Crossing to flying Canberra to Melbourne (or a motorbike at peak hour, or solo yachting across) for instance? Can anyone advise the practical/standard flight risk assessment approach, other than pilot's gut/experience after reviewing the flight path? Obviously this would be very plane-pilot specific with variables like season and safety arrangements having to be tied down. If you survive the crash, flight planning/reporting and EPRIBS/GPS positioning mean you don't have to survive misserable unpleasant shark infested cold water too long (based on reports of those planes that have gone in). That makes it a lot safer than years ago. I am risk averse, but fear should not enter objective aviation risk assesments. That is what the lay public and oldschool wives are for

Yes to all you say Nev, which is why I am not rushing into anything until I tie down the risks of available options a LOT more. We don’t need more bad press and court cases from botched crossings. Your concerns are a good starting point. Thank you My Jabiru engine related posts are driven by my absolute fear of engine failure over water. The good Jabiru crash worthiness into paddocks is only part of any risk mitigation (Not suggesting Jabirus are worse than anything else in water ditching as I have no data yet). I would love a twin or turbo prop if I had a few million dollars Oh yeah. My mention of the Sonerai is to give others who are lind enough to care a starting point idea of the performance I aspire to and budget I would like to match. Safety wise I think the CrMo fuselage is it's key safety feature, and I hadn't thought of flight over water safety for the Sonerai (I am pretty sure several have flown across Bass Straight). Like most people I want massive performance, no noise, great comfort, good flight characterisitcs, VTOL and safety and reliability ... at a price below that at which it is possible I was advised by my friend who ditched his amphibian that a small one offers little advantage in a sea diching’s unless it is millpond calm, which is why I was willing to omit them as an option. Thankyou for confirming that a small amphibian is of marginal advantage. I was planning to buy a Consolidated Catalina with two noisy things, until I broke open my piggy bank If I develop anything worthy, or have further questions, I will post to the Flights over water or Bass Straight crossing threads after researching a lot more. Since building my own aeroplane is not out of the question, the safe design and build features for sea diching in a non-amphibian are high on my to list. I will post it, if I produce/collate something worthy enough. If my risk assessment is that I cannot get/build a plane that can cross Bass Straight at an acceptable risk, I will focus on a local flying options and keep making make Sir R Branson or the little Irishman cover the flight risks PS: Is the jet powered Cri Cri a reasonable twin IYHO? LOL, roll about laughting

I think you are mistaking “shock-cooling” for carb-icing. I had never heard about it either, until I looked into Jabiru Engine reliability. It seems to be the big issue discussed about Jab Engines at the moment, and one that the water cooled heads (ie: Rotec) claim to cure. I think it was Jabiru Owners Group Rotec W/C Heads postings that made me mention it. As I understand the terminology usage is as defined by Shock cooling - WikiVividly and/or wikipedia The claim is that early Jab failure is common where many touch and goes are performed (I haven't found the direct link sorry). If true it means flight schools will never meet the TBO, so it should be possible to show if statistically differences between trainers and cross-country planes exist. Jabawocky doesn’t believe in shock cooling. Shock Cooling - Myth Busted!! - PPRuNe Forums. I think it is rapid thermal cycling, and https://www.casa.gov.au/file/169776/download?token=BcnNQEBY indicates issues with Jab engine through 3/8” bolts, so I suspect thermal cycling was not been completely allowed for in their original design and any long term cyclic engine testing by Jabiru has not picked it up. I did say before, bringing any new engine to market is not easy, but when debugging (think poorly developed software) is done by customers it can fatally damage reputation (The Lotus motor killed Jensen Motors when Lotus used the Jensen Healy as a Guiney pig). The thread ‘CHT for Jabiru 6cyl’ suggests CHT and heads on Jabs are an issue. jetjr says multiple CHT are essential for the six. I realise that it could be pilots running the engines too hard for too long (as you indicate), rather than a Jabiru engine problem, or shock cooling and that you can’t make generalisations about all engines. I am not anti-Jabiru Engines (Lotus engines are good engines, but...). I am performing due diligence risk assessment (a responsibility on all aircraft owners) to protect myself and passengers. That means the claims must be assessed somehow and until it is that option remains risky. Jabiru reputation (and any reality behind it) has to be addressed by Jabiru, if it is to win back opinion as expressed on websites across the globe. That will require hard data and clear demonstrations of reliability/TBO. I hope my posting are not read as direct judgement as I am not in a position to make such, and think my post identify ‘commonly held belief’ and seek objective confiration or correction like you have provided. Thankyou :-)

Thank you Dafydd, I have read your posts with serious interest and find them reassuring. Does not a steel space-fame absorb significant energy during deformation, unless it is manufactured from high tensile material and/or has 'brittle' welds. Is not a ductile space-frame capable of significant energy absorption, and if it had a sufficiently high yield strength it would provide equivalent rigid body (separation) protection to a lighter non-ductile structure of higher yields strength? I am not current with aircraft CrMo steels, but believe (from Australian Supplier data) the available tubing is normalized grade 4130 having a typical ductility of 12% at >600 MPa. That makes them pretty tough (energy absorbing). Maybe you are saying is that a space frame built as strong as yours will not buckle until it has killed you with G forces!? Do you think a cleverly designed space-frame could start absorbing energy by crumpling (controlled bucking, which I know is unpredictable unless cleverly designed) before it kills you with G forces? Based on images posted here Jabirus seem to absorb the energy by ripping of the front of your protective cocoon, so it would be no worse than that if members were designed to buckle outwards. This buckling would commence once the other energy absorbing structures are fully crushed.

Yes, a fuel injected, water cooled heads, treated liners, 6cyl in a J400 is attractive to me Sweeeet On a lighter note, I love your profile picture. You have to love the Stealth SSDR Archon SF-1

Thanks for the reassurance about Jabiru inflight engine safety Litespeed. I haven't researched the data or found the reliability statistics as you have. Do you have a report or site link? I am going on what associates believe, a few web discussions from around the world and my own inspection of internals from early Jabiru motors. I am not an expert and have no vested interest except my own safety. I would like Jabiru to keep being a commerical worldwide success, so believe they have to address this perception (reality?) somehow. Things like touch-and-go thermal shock sensitivity and uneven cylinder head temperatures ... seem beyond the "pilot/maintenance" responsibility IMHO. A lot of posters don't like Jabiru because they claim Jabiru have said "Its your fault"! I see precious few recommending the Jabiru motor (usually "here is an alternative" or "her is a Jabiru motor upgrade/fix"). I think this should probably posted elsewhere. Thanks again for keeping the perspective balanced.

Thank you for alerting me to Australian Aircraft Kits facthunter. I found Ole's great web site and his planes look as described. I should have noted my aircraft requirement is a quiet tourer with good visibility, that can cover distance fast and economically while enjoying Australia from the air. Ideally it would be amphibious so I could go to the lakes, wilderness and islands around Tasmania (an offer better odds in a sea ditching), but that is too incompatible with my key requirements and finances. I am now looking at the safety of various candidate planes and building one to suit based on a proven aircraft like the Sonerai is an option. I think the 'delicate' planes that match my requirements do not have to be unsafe if crashed, just as tin can cars of today can achieve reasonable crash safety by cleverly engineered design optimisation. I recall a friend who lay on a bed in his office, to cope with the pain of his broken/fixed spine, for several years after crashing his amphibian on take-off (due I believe to slight leakage into the fuselage with insufficient baffling to prevent serious mass transfer upon rotation, though the crash report never concluded it). His wife nearly drowned being caught in her harness and he saved her by diving on the wreck (with minimal use of his legs)! It makes me take safety really serious and question options that may at first seem safer options, especially for sea crossings.

Thanks for confirming their reputation for being safe airframe Litespeed. The Small aircraft crashworthiness thread contains a few posts about front of the cab collapse, that I will reread. I am not anti-fibre composite and at least partial CFRP is the future for commercial aircraft for most fliers IMHO, but something like a cheaper affordable version of http://www.worldrecordplane.com/ Sonerai 2L has my attention currently. I have flown in Eugene Reid’s very nice Jabiru LSA 55/3J. A J400 on VH rego would allow me to fly my regular trip to Canberra across Bass Straight with family, if I bring active flying forwards. My concern with Jabiru's has always been the engine (A Bass Straight ditching is not nice, safe or cheap). Steel liners and other problems I saw with early engines have translated to Jabiru's reputation today (Purely my perception). It is an impressive engine, given how hard it is to build any commercial engine (Porsche found out when it tried an aero engine), but primary risk removal is the best safety measure from my perspective as a purchaser. If D-Motor can overcome their own serious problems, the new D-motor will add futher pressure from the opposite end of aero engine design to the Rotax, so hopefully Jabiru turns this major issue around. Achieving typical engine life equal to their specified TBO is preventing me getting one as their prices are good. Thanks again for your welcome and input,

Hello all who read this, Sorry for adding bandwidth, but the nag pop-up insists I post to this thread. My flying status is "inactive" except for PC flight simulator and CFD. I was following the Small aircraft crashworthiness thread and was interested in some attachments so had to register! I started learning on a Scout Mk3 (so don't take it I don't take risks) in the 80s, but after seeing the results of poor crashworthiness (not just on Scouts) required due to poor piloting and ill-conceived aircraft modifications/builds, I decided the inevitable expensive painful stay in hospital followed by life in a wheelchair was not for me as a learning experience. Watching such events close up and personal really shakes one's confidence and makes the need for risk mitigation crystal clear. I am looking to getting a safe aircraft when I will no longer feel guilty indulging myself while my children still need me: Sound familiar? The Small aircraft crashworthiness thread has been excellent reading with special thanks to Dafydd Llewellyn for his excellent, balanced and authoritative input. When you really know what you are talking about you should not be expected word it as humble opinion, no matter how humble you are in person. Poor piloting decisions made under pressure and limited time can be forgiven more easily than poor primary, secondary and tertiary aircraft safety decisions to which time and sense can be used until the risk is brought below the level you are willing to take. To quote the cliché that has kept me safe so far: "There are old pilots and bold (meaning those with poor judgment who do not mitigate risk) pilots, but there are no old bold pilots." I hope one day to be, and remain to be, an able bodied old pilot :-) If you have an 'safe' unmodified quality factory built new plane, designed and maintained to all requirements my concern may seem excessive, however I am looking at the experimental aircraft category due to my engineering background and finances ;-). It is the thrill of flying, not the adrenaline rush created by surviving another flight that attracts me. Sorry for rambling on, but it will probably be my last for a long while. Thanks again to all for your constructive informative postings, Jethro