Guest Andys@coffs Posted July 31, 2014 Posted July 31, 2014 But the point about the engine just stopping when the sump runs dry rather than coughing and spluttering is true at least in my J230. I got one cough, and then within 10seconds it was stopped dead. Shoulder level Fuel cocks back on (not fitted to all J aircraft now) wait 30 seconds for gravity to do its job, one push on the starter and away it went. Andy
motzartmerv Posted July 31, 2014 Posted July 31, 2014 Yes they stop very quickly when running dry. Lucky to get a splutter.
geoffreywh Posted July 31, 2014 Posted July 31, 2014 I was about to send a blast off in the direction of people that wrote" Jabiru tank gauges are hard to read " Like , that makes it OK to run out of fuel....Then I looked up the distance between Archerfield , The planes home base, and Runcorn, The crash site ..... It's 12kms ! ..........If I assume that the flight was from Archerfield to Runcorn,........... 5 minutes???? .............. of course they could have been on a Nav ect..........I'm gonna wait quietly now for more information......... 1
kaz3g Posted July 31, 2014 Posted July 31, 2014 Might work if you get unbiased people who have real experience at troubleshooting. I'm dropping in at CAMit in about 5 weeks. Today is my last day on this computer for 7 weeks Nev Have a great holiday, Nev. Kaz
turboplanner Posted July 31, 2014 Posted July 31, 2014 Nev's will be the one blowing all the smoke! OK, The Bert Munro book was unbelievable - like when he was on the way back to California from Bonneville, and drive around the back of Edwards Air Force Base until he found a gap in the fence, and when he was caught in the restricted area in his old $60 car and home made trailer with the streamliner on board, talked he way into being taken around to see the top pilots on the Bell X1 program, and from that getting them to help redesign the streamliner to stop it getting out of control every time he lifted his head to see. 1
facthunter Posted July 31, 2014 Posted July 31, 2014 Mr Munroe was always on the bot. He actually turned up at a place in Newcastle where I was working. The boss summed him up pretty quick. " We don't need that fella . He doesn't want to pay for anything.". Having said all that the book is a good read. The film is entertaining but altered to make it more "whatever" to sell. He really did achieve some outstanding speeds and made most of his parts. ( Conrods out of tractor axles and cast his pistons himself. as one does). The photos are from a hardware shop in Invercargill. Hayes I think. Nev
dazza 38 Posted July 31, 2014 Posted July 31, 2014 I was about to send a blast off in the direction of people that wrote" Jabiru tank gauges are hard to read " Like , that makes it OK to run out of fuel....Then I looked up the distance between Archerfield , The planes home base, and Runcorn, The crash site ..... It's 12kms ! ..........If I assume that the flight was from Archerfield to Runcorn,........... 5 minutes???? .............. of course they could have been on a Nav ect..........I'm gonna wait quietly now for more information......... They were on their way back to Archerfield after flying over to Nth Stradbroke Is. See my post # 49
Guest Andys@coffs Posted July 31, 2014 Posted July 31, 2014 So, is there anyone with a jab that has run it dry had the engine run rough for a period of time before stopping? Enough time to make a mayday call and reportedly for police to arrange for road closures etc...... Doesn't add up for me, are we sure fuel exhaustion is the answer here? Jabs in General have capacity for 5+ hrs duration. For a one hr flight to suffer exhaustion you would be taking off with less than 20 litres. Not impossible, but to me improbable at near to start of flying for the day The wings in a 170 are wet wings, tear one off and both will end up empty pretty quickly unless somehow the fuel lines self seal, but if avgas was used I guess you should end up with blue/green dye on the ground, if mogas then...nothing visual I presume? The real question assuming fuselage intact, was the sump empty? Andy
01rmb Posted July 31, 2014 Posted July 31, 2014 Icing is not simply a temp related thing.Saying its likely because it was cold is not telling the full story. There's much more to it then that. I'd be very surprised it it was ice. At 7.30 this morning, in Brisbane it was 9.8C and 72% humidity, dew point 5C. Descent power.... http://www.casa.gov.au/wcmswr/_assets/main/pilots/download/carburettor_icing_chart.pdf I was being brief and just saying it was cold. A full analysis considering the dew point and humidity conditions as quoted by Oscar plus the fact he would have been on a decent from 1500' (another 3 degrees cooler) on a final approach descending with an idling engine (he was less than 4nm from the threshold) - he would have been in the serious carby icing conditions at all power settings according to the attached CASA carburettor icing chart. 2 1 1
Oscar Posted July 31, 2014 Posted July 31, 2014 Yes, that's the chart I checked up on before making that comment. There's nothing we appear to know that suggests that it was icing and not fuel, but the conditions certainly put the thing pretty much smack in the middle of the worst-case scenario for icing, if the chart is to be believed.
motzartmerv Posted July 31, 2014 Posted July 31, 2014 I hope for all our sakes you're right! We live in carby ice land down here and have experienced it with the jab engines countless times. But total loss of power would require some significant ice. Possible I Spose, and the conditions look good for it. I just wanna know how he got a jab started when it was 9 deg's!!! 1 1
AVOCET Posted July 31, 2014 Posted July 31, 2014 I I hope for all our sakes you're right!We live in carby ice land down here and have experienced it with the jab engines countless times. But total loss of power would require some significant ice. Possible I Spose, and the conditions look good for it. I just wanna know how he got a jab started when it was 9 deg's!!! o I used to start my old sp6 in -7 deg back in the old days ( cup of hot water over the carby)
01rmb Posted July 31, 2014 Posted July 31, 2014 We probably get a bit lazy here in Queensland with thinking about carby icing because it is generally warm but maybe (and we need the true cause to be known to be sure) this is a lesson that you can not ever be complacent with anything when you are flying.
Keenaviator Posted July 31, 2014 Posted July 31, 2014 My new (old) 2200A with its small starter motor would have been a real challenge to start in cooler conditions. But I have fitted a 'cold start kit' which makes starting a breeze. With this kit you don't have to achieve the normally high cranking rpm to get the ignition system to produce a spark. Laurie. 1
AVOCET Posted July 31, 2014 Posted July 31, 2014 We probably get a bit lazy here in Queensland with thinking about carby icing because it is generally warm but maybe (and we need the true cause to be known to be sure) this is a lesson that you can not ever be complacent with anything when you are flying. That's right . I did my training in bundy and that's all the carby heat was ever used for . Training that is . But when I moved to south australia , Well , I found out how real it can be ! Flying along on a buitiful sunny day , Coff , splutter , at 5.5 tho . Clad the the carby heat actually worked !! May be , just may be that , ( I'm assuming here ) the pilot wrongly assumed , " ruff running JABIRU ,must be stuffed " " ", broken throu bolt ?" I know this happened to me when my 750 hr second hand , flying school jabiru engine started to rattle and had no oil press . Guess what , I thought IDE done a thru bolt , It was a cracked exhaust pipe shorting out the O/P sender wire !! Next thing to happen ? Prang ! Moral of this story , ? Don't assume jab engines are rubbish . 3
Teckair Posted August 1, 2014 Posted August 1, 2014 On the subject of fuel starvation - before everyone totally buries the pilot for flying with empty tanks - at that time of day with the early morning cool temperature on a 3 mile final decent I would think that carby icing could be a possibility.It still should be a manageable situation. Yes a possibility but the 'early morning cool temperature' does not make it any more likely. 1
Teckair Posted August 1, 2014 Posted August 1, 2014 my first thought was carby ice !It's that time of year . Why?
Dafydd Llewellyn Posted August 1, 2014 Posted August 1, 2014 As is the case with a lot of what is reported in the press, people jump to conclusions way too early and get it way too wrong way too often.I am disappointed that our new RAAus CEO has dropped Jabiru in the deep end and held their head under water by bad mouthing them in the media after only a few weeks in the job. He has not done Jabiru or any Jabiru owner any good by trashing them in public rather than dealing with any possible problem with engine reliability in private. Personally I would like to see him sort out the administrative mess that is the aircraft registration system before running around saying things in the papers especially if as in this case it was factually incorrect to blame the aircraft. Agree completely. Has RAA done any statistical analysis of the accident rate due to airworthiness causes, for RAA aircraft by type and number in the fleet? Or am I making the mistake of expecting logical behaviour, again? Does RAA even know how many aircraft of each type there actually are in the fleet? Or would revealing this be too embarrassing, in view of the inflated claims about the size of the fleet? I do not imagine that the current Board would consider it in anybody's interest to be other than honest about these things, but are the answers actually available? And if not, why not? 1
Dafydd Llewellyn Posted August 1, 2014 Posted August 1, 2014 Why? Why not? When an engine stops in flight, but runs sweetly when subsequently tested, induction icing is a prime suspect, as is fuel starvation. 2
Teckair Posted August 1, 2014 Posted August 1, 2014 WWhy not ? Cold air cannot contain as much moisture as warm air, all you need for carburetor ice is moisture in the air the ambient temperature being cold is not an indicator of possible carburetor ice.
Old Koreelah Posted August 1, 2014 Posted August 1, 2014 ...The photos are from a hardware shop in Invercargill. Hayes I think. Nev Yep. The most amazing hardware store. Restored bikes between the rows of fasteners and power tools. Bikes I have never heard of. Invercargill is worth a visit.
AVOCET Posted August 1, 2014 Posted August 1, 2014 I've been a bit reluctant to mention this before ; having been a reader of this forum for a while now , I carn't help thinking that there is a correlation between what is read on this forum ( talking jab engines ) and what happens when a pilot has an inflight problem ( jab engine ) and immediately assumes , albeit wrongly , "Gees " must be that bloody jab engine . I guess what I'm saying is that it's almost an automated response due to the neg feedback we are all exposed to . I know this was the case with me . 1
Teckair Posted August 1, 2014 Posted August 1, 2014 Why not? When an engine stops in flight, but runs sweetly when subsequently tested, induction icing is a prime suspect, as is fuel starvation. Cold air cannot contain as much moisture as warm air, all you need for carburetor ice is moisture in the air the ambient temperature being cold is not an indicator of possible carburetor ice.
AVOCET Posted August 1, 2014 Posted August 1, 2014 C Cold air cannot contain as much moisture as warm air, all you need for carburetor ice is moisture in the air the ambient temperature being cold is not an indicator of possible carburetor ice. carby ice 101
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