Yet another one down from Basair
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FL170, the post was deleted from before mine that said that this aircraft actually was a Tomahawk. Next time I'll quote it for people reading later-on.
Perhaps someone should have told that pilot that a rotax being both water AND air cooled, if the coolant is lost (possible scenario) that it can be safely flown home at 4,000rpm or less (of a max 5,800'ish). There would be very few other reasons as to why it would overheat, eg busted hose, coolant dropped out etc etc. Also demonstrates the importance of multiple CHT and EGT gauges which are generally not standard these days, with these the pilot can make a more informed decision about what is going on under the hood before ditching.
Perhaps someone should have told that pilot that a rotax being both water AND air cooled, if the coolant is lost (possible scenario) that it can be safely flown home at 4,000rpm or less (of a max 5,800'ish). There would be very few other reasons as to why it would overheat, eg busted hose, coolant dropped out etc etc. Also demonstrates the importance of multiple CHT and EGT gauges which are generally not standard these days, with these the pilot can make a more informed decision about what is going on under the hood before ditching.
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XXX, Have you seen the plane or are you speculating about the cause?
(Im not having a dig, just curious)
Personally I reckon if it was simply overheating then landing in a paddock that close to BK is a bit of overkill, i hope that there is more to it than that...
Still the plane is probably fixable, the driver is alive, can't complain too much about that!
(Im not having a dig, just curious)
Personally I reckon if it was simply overheating then landing in a paddock that close to BK is a bit of overkill, i hope that there is more to it than that...
Still the plane is probably fixable, the driver is alive, can't complain too much about that!
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Douche, there was mention of it overheating. I was just stating a known fact about Rotaxes and overheating, no crash analysis intended in this instance 
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Seriously, where do you guys come up with this stuff. 2,300 rpm, in a Rotax 912??? No wonder it crashed! The Rotax 912S revs out at up to 5,800rpm and 5,000 - 5,100 rpm in the cruise. Better take note of the RPM gauge next time you're taking off 
That's why they sound like sewing machines
Performance 69.0kw - 95hp at 5500
Take Off Performance 73.5kw - 100hp at 5800 (max 5 minutes)
(In your defence bizzbody, prop speed at max RPM would be around 2,386 rpm with the 2.43 reduction drive)
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bizzbody says: no EGT in that aircraft. I also think its Max RPM is around 2300
That's why they sound like sewing machines Performance 69.0kw - 95hp at 5500
Take Off Performance 73.5kw - 100hp at 5800 (max 5 minutes)
(In your defence bizzbody, prop speed at max RPM would be around 2,386 rpm with the 2.43 reduction drive)
I have never seen a Taco in a Tecnam.
...although on Friday I did have a Burger in a Baron
...although on Friday I did have a Burger in a Baron
Cynical Pilot: Grobs
G'day
There is ONE of the three ugly sisters at Scone and my sources tell me it is getting looked after with new windscreen, touched up Gel-coat, Becker ADF installed and so on
There is ONE of the three ugly sisters at Scone and my sources tell me it is getting looked after with new windscreen, touched up Gel-coat, Becker ADF installed and so on
BIZZYBODY IS ABSOLUTELY CORRECT!
The TECNAM P2002 JF is a GA certified aircraft and as such, the tacho is cable driven from the rear of the engine and shows rpm at the prop, not engine rpm as is shown in the LSA and recreational models.
The TECNAM P2002 JF is a GA certified aircraft and as such, the tacho is cable driven from the rear of the engine and shows rpm at the prop, not engine rpm as is shown in the LSA and recreational models.
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now thats just weird, i have many hrs in a RAAus tecnam, but not VH rego'd tecies. i would rather know what the engine is doing instead of the prop. (fixed pitch situation only)
the engine speed tacho has green arc to 5300 rpm, yellow from 5300 to 5800 the red from then on, you can fly it in the yellow RPM band for 5 mins max, or risk overheating. if you have a Prop tacho, how do you know if the engine isnt in an overspeed situation? especilly if you dont know the cable drive to the tacho isnt giving false reading? has worn drive gear? etc. etc. he might have set the prop RPM at high cruise, then begun a cruise descent at the same throttle setting that allowed the rpm to creep up, a quick glance at the prop RPM might show it as right on the limit of the green arc, but the actual engine RPW will be an unknown.
i like to know what my engines are doing.
the engine speed tacho has green arc to 5300 rpm, yellow from 5300 to 5800 the red from then on, you can fly it in the yellow RPM band for 5 mins max, or risk overheating. if you have a Prop tacho, how do you know if the engine isnt in an overspeed situation? especilly if you dont know the cable drive to the tacho isnt giving false reading? has worn drive gear? etc. etc. he might have set the prop RPM at high cruise, then begun a cruise descent at the same throttle setting that allowed the rpm to creep up, a quick glance at the prop RPM might show it as right on the limit of the green arc, but the actual engine RPW will be an unknown.
i like to know what my engines are doing.
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The 912 does indeed have a flexible cable driven off the rear of the engine but given the prop gearbox is at the front of the engine I'm not too sure on how it could measure the prop speed unless the cable came from the front of the engine.
That being said though in theory provided that the prop was set to a fixed pitch and that the rpm gauge was appropriately marked to correspond to the appropriate prop versus engine rpm then conceivably this could be possible, however i find it hard to believe as if the prop pitch was changed or the prop changed the calibration would be all screwed up.
I will need much more convincing!
(I have 550 hours behind a 912 and the maintained it during that time so I know a little about them). I'd be surprised if the raa versus ga lsa ones would be any different in terms of engine instrumentation.
That being said though in theory provided that the prop was set to a fixed pitch and that the rpm gauge was appropriately marked to correspond to the appropriate prop versus engine rpm then conceivably this could be possible, however i find it hard to believe as if the prop pitch was changed or the prop changed the calibration would be all screwed up.
I will need much more convincing!
(I have 550 hours behind a 912 and the maintained it during that time so I know a little about them). I'd be surprised if the raa versus ga lsa ones would be any different in terms of engine instrumentation.
Last edited by VH-XXX; 6th Sep 2009 at 13:28.
It's a fixed pitch prop. I'm fairly sure it reads engine RPM but runs it through the same reduction ratio the prop goes through. Whether it uses a gear or just calibrated the numbers on the tacho differently I have no idea though.
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Engine RPM are about double what pilots of other “Jurassic-era” machines are used to, but despite spinning twice as fast, the Rotax is significantly quieter.
In the -JF the tachometer counts (reduction-gear reduced) propeller RPM,
which should allay any frightened quivering or consternation amongst the die-hard
vintage — read “conventional” — aircraft pilots.
In the -JF the tachometer counts (reduction-gear reduced) propeller RPM,
which should allay any frightened quivering or consternation amongst the die-hard
vintage — read “conventional” — aircraft pilots.
www.tecnamaircraft.co.uk/p2002article.pdf
The confusion on Tacho readings seems to be purely due to the difference with the certified versions. You guys must be wondering what planet the other is on....
Regards the discussion about worn tacho drives and prop changes, -
the prop and engine always spin at the same ratio regardless. Any tacho errors are like any instrument errors,... always lurking.
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Thanks for finding those bb, most handy. Have flown atleast 10 different types with 912's from 80 hp thru to the 924 and hadn't come across this.
I guess in the end it doesn't matter what is displayed on the tacho as long as it is consistent (between same aircraft types) and is appropriately marked with maximums etc.
I guess in the end it doesn't matter what is displayed on the tacho as long as it is consistent (between same aircraft types) and is appropriately marked with maximums etc.
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Googled a POH for it and surprise surprise:
http://www.flugschule-klv.at/klv/manual-P2002JF.pdf
Gear reduction ratio is -2.4286:1
It's as simple as putting a different card behind the needle in the Tachometer.
Ultralights- POH states operational limits on the RPM of the prop however it also gives you engine speed (this ratio of 2.4286 does not change)
Good old POH, wasn't there a discussion in a prior thread about just how much info can be gained from them! No need to speculate
http://www.flugschule-klv.at/klv/manual-P2002JF.pdf
Gear reduction ratio is -2.4286:1
It's as simple as putting a different card behind the needle in the Tachometer.
Ultralights- POH states operational limits on the RPM of the prop however it also gives you engine speed (this ratio of 2.4286 does not change)
Good old POH, wasn't there a discussion in a prior thread about just how much info can be gained from them! No need to speculate
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I find it interesting that this was done probably to alleviate peoples concerns to make them think that the engine is not revving twice as fast as a comparable Lycoming ! I guess the manufacturers aren't comfortable with pilots thinking that the engine is revving at up to 5,800 rpm.........