M61A1 Posted November 23, 2012 Posted November 23, 2012 In a 2stroke? Your braver man than me. ;) Not that I think it's a good idea in any single engine a/c, but I recall stats on this forum (and , I think, the "sport pilot" mag) that showed that while there were a higher number of 2 strokes on the register, 4 strokes had more recorded failures (numerically).
motzartmerv Posted November 23, 2012 Posted November 23, 2012 Yea, it doesn't matter what engine, that sort of flying is deadly.. And you will excuse me if I dont buy the stats you claim. There are lies, dam lies and statistics.. The average Australian has less then 2 arms..;) Thats a fact that doesn't represent the true story;) 1
M61A1 Posted November 23, 2012 Posted November 23, 2012 Yea, it doesn't matter what engine, that sort of flying is deadly.. And you will excuse me if I dont buy the stats you claim. There are lies, dam lies and statistics.. The average Australian has less then 2 arms..;) Thats a fact that doesn't represent the true story;) The stats, I'm sure came from a "Sport Pilot "mag, and were just based on the numbers on the register and the number of reported failures. It's entirely possibe that the reporting is not accurate. That said, a well maintained 2 stroke is very reliable, it just needs more maintenance and doesn't last as long. Possibly those flying them these days look after them a little better, or use them less. One would need a lot more data to arrive at a scientific conclusion. 2
Gibbo Posted November 23, 2012 Posted November 23, 2012 Yep, Oil covered windscreen could make your pucker valve work overtime!!! and reach for the big red handle...whether there or not!When I think of gilgandra Paddocks....lots of paddocks and flat! comes to mind Happy farmer.. Harvest is starting up. :) If rice then full of water.
Teckair Posted November 23, 2012 Posted November 23, 2012 When I started flying most ultralights had 2 strokes fitted and over that time I managed to have a lot of engine failures with both 2 and 4 stokes. In my experience if treated correctly a 2 stroke was as good as any other engine almost all problems were related to installation, maintenance and operator errors. I would never choose to skim the trees on final with any engine. When descending including on final I set the throttle on idle after reducing power over time doing the circuit so as to not shock cool the engine, when descending from a height still with throttle on idle but a burst of power every 500 ft. This always worked for me many, many times even though others will tell you it is the wrong way. I can say descending with part power around 50% is likely to cause a seizure with 2 stoke motors. Richard. 2
Sapphire Posted November 23, 2012 Posted November 23, 2012 TA said: I can say descending with part power around 50% is likely to cause a seizure : If you decend in circuit with greater than half power you do big circuits skimming over trees. Even bursts of power in a Sapphire will send to to an overshoot-especially if you are also hit by a thermal. Give up, shut off the engine, and continue your flight till the plane wants to come down.
Sapphire Posted November 23, 2012 Posted November 23, 2012 sapphire . the high egt's are normal for low throttle openings, and temp and heat energy are a differet thing A factor with long glides with pre-mix is lack of lubricant, as with virtually no fuel going through there is little oil as well. This is off topic so PM me if you wish. Nev Yes, having an idle or near idle throttle position gives the engine little lubrication resulting in a cold seizure. The explanation for high egt at low throttle settings given to me is that little air enters the engine which tends to have a cooling effect at high power settings. You're also saying there is high temp but small heat energy in the exhaust gasses at low power settings, so your piston etc won't burn up
facthunter Posted November 23, 2012 Posted November 23, 2012 The engine is cooled by evaporation of fuel and airflow through the engine, as well as the cooling system . I have always said( half jokingly) that a 2 stroke is fuel cooled. The full throttle settings are quite rich and a couple of hundred revs lower the mixture leans out causing an EGT rise. This is when I have seen egt's peak in a 2 stroke. We understand about the oil at low throttle settings, I think. Regarding the part throttle descents say over 50% I cannot recall anyone speaking of the engine being likely to fail under those conditions and I cannot see why it would be a problem if the mixture is set correctly. I can't see that a long idle descent is going to have your engine in a good state to do a full power go around( Is there any other kind? The oil pump (inlieu of premix would pump some oil in on descent so you should be better off. I have always favoured premix over oil pump anyhow but on cross country you are better off with the pump, from a convenience point of view. Nev
Guest Andys@coffs Posted November 23, 2012 Posted November 23, 2012 582 had oil injection added as a partial solution to this problem. The injection injects whether the carb is closed or not. Obviously the carb setting does affect how much oil but it doesnt go down to zero if the slides are fully shut. (I seem to recall the ratio oil to petrol was about 1/2 what it is at full throttle when at a low power setting)....Its been a while since I played behind a 582 maybe my recollection is busted..... Andy
Sapphire Posted November 23, 2012 Posted November 23, 2012 Teckair, your post to me has disappeared. Anyways, the last sentence in my post is a joke-I don't switch off the engine in flight. The rest explains having to do long approaches in a Sapphire in order to keep the power setting satisfactory. My Sapphire did not have flaps and was more slippery. In fact I thermalled with it and reduced the fuel flow to to 4 L per hour.
pilotdave69 Posted November 23, 2012 Posted November 23, 2012 http://www.dailyliberal.com.au/story/1139644/plane-lucky-pilot-and-passenger-walk-away-from-crash/?cs=112 Some more photos of the Cirrus and story which follows. I do wonder how rough this paddock would of been to land in, large enough, would of been bumpy, lose landing gear anyway, less more damage than using chute, more injury or less ? no one will know. I guess, had he not used chute and forced landing was worse off, people would of asked, why not use chute! So many questions to ponder! Either way. well done!
Guest Maj Millard Posted November 23, 2012 Posted November 23, 2012 Yes pulling in the shroud lines on a fully opened chute (when on the ground ) does work well, and has the effect of 'spilling' the air from the canopy, which will then deflate. During Army training we were taught to keep pulling in the lines 'hand over hand' until the chute collapsed. Whilst sport jumping about the same time with round canopys, we would sometimes get dragged along the ground if the wind was up. With that equipment we just activated one of the shoulder mounted riser releases, which collapsed the chute instantly. The riser releases (2) gave you the option of 'cutting away' the main chute at altitude if it malfunctioned, to allow for a cleaner and safer reserve deployment. (plan B !) I would agree that the person in the video toward the end is either unconcous or stunned. Possibly a student.........................................Maj...
Mick Posted November 23, 2012 Posted November 23, 2012 Mick you obviously know John...I have met him several times at dealer conferences and supply stuff for the Rocky branch although of course he doesn't own them anymore. I know he kept the linked transportable repeater side of the business and thought maybe he was doing something with thatespecially with Emerald being one of the points. Well he has a enough money now to buy a jet for sure Yep I do know John Nixon of Gladstone but after looking at the pic in the article in the Daily Liberal linked above I realised I also know the John Nixon of Dubbo that was involved in this accident. I helped to teach John ( of Dubbo ) to fly R/C about 15 years ago.
Old Koreelah Posted November 23, 2012 Posted November 23, 2012 I do wonder how rough this paddock would of been to land in... Perhaps a major factor is the tiny wheels these slippery aircraft are fitted with. Never intended for rough strips, it may be safer to pop the chute. I was mystified by the pilot's description of the launch sequence: "The chute went off like a missile out the back of the aircraft and made a hell of a noise. We came to an almighty stop and the plane went into a nose down attitude as the parachute inflated. "About six seconds later the line cutters (small explosive devices) at the back of plane went off, levelling the aircraft." What was that all about?
M61A1 Posted November 24, 2012 Posted November 24, 2012 Perhaps a major factor is the tiny wheels these slippery aircraft are fitted with. Never intended for rough strips, it may be safer to pop the chute.I was mystified by the pilot's description of the launch sequence: "The chute went off like a missile out the back of the aircraft and made a hell of a noise. We came to an almighty stop and the plane went into a nose down attitude as the parachute inflated. "About six seconds later the line cutters (small explosive devices) at the back of plane went off, levelling the aircraft." What was that all about? Bear in mind I know nothing of the particular egress system in the article, But as an ex-military Armourer (includes ejection/egress sytems), some systems have a mechanism (for want of a better term) that will allow gradual canopy opening, using reefer lines, and also change the bridle (the bit attaching to the a/c) position at some time in the sequence. I don't think it would be good to have your chute deploy fully immediately, or to have the load immediately on the front section of the bridle, otherwise the a/c would pitch up as soon as the chute deployed.
Kyle Communications Posted November 24, 2012 Posted November 24, 2012 Yes Mick...now I see the pic certainly not the same guy I know
dazza 38 Posted November 24, 2012 Posted November 24, 2012 The cirrus chute has a ring which all the chute lines go through.This ring slows down the opening of the chute.As the ring slides down towards the aircraft, the chute gradually opens up.All this happens in about a second. There is a video of it on youtube. Which shows the deployment & the ring sliding down. I dunno how to put it on here.But I will put it on FB. This is from memory.Could be wrong. I remember reading about it years ago.
Ballpoint 246niner Posted November 29, 2012 Posted November 29, 2012 rumour has it that the pilot of said Cirrus noted fluctuating oil pressures a long time prior to flameout and passed at least 2 seviciceable AD's before the talk got loud and the thing seized up... makes you wonder if this is the case.....
Patrick Normoyle Posted November 29, 2012 Posted November 29, 2012 A few years back an SR20 cirrus, departed Hamilton Island in the Whitsundays, the engine failed on the turn off crosswind onto track, the aircraft was at about 700 feet with 2 occupants, the pilot in command ( I use the term very loosely here ) didn't try a restart or return to the field even for a downwind landing ( about 7 knots ), he grabbed the oh "Jesus" handle ( not ment to offend any religious folks out there ) and floated down to the soft landing in the ocean. Very average in my opinion, I'm a fighter, I'll fight it all the way to a landing. 2
pylon500 Posted November 29, 2012 Posted November 29, 2012 Something about 'A pilot and too much money is soon flying more plane than he can handle?'
dazza 38 Posted November 29, 2012 Posted November 29, 2012 A few years back an SR20 cirrus, departed Hamilton Island in the Whitsundays, the engine failed on the turn off crosswind onto track, the aircraft was at about 700 feet with 2 occupants, the pilot in command ( I use the term very loosely here ) didn't try a restart or return to the field even for a downwind landing ( about 7 knots ), he grabbed the oh "Jesus" handle ( not ment to offend any religious folks out there ) and floated down to the soft landing in the ocean. Very average in my opinion, I'm a fighter, I'll fight it all the way to a landing. The pilot was Steve Maltby. The Australian importer of cirrus aircraft. He was the only occupant in the aircraft.
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