Flying over square
Jaba,
No dramas, discussion is good.
CAR 138 as quoted is where it says the POH MUST be complied with.
Before landing is where almost every POH states full fine. I am as guilty of assumptions as anyone, but to me before landing means on final, not downwind.
As for annoying the neighbours.....
I reckon if they live near an airport, either they love the noise
Or they knew it was there when they moved in and so should put up or shut up.
Something we do agree on?
No dramas, discussion is good.
CAR 138 as quoted is where it says the POH MUST be complied with.
Before landing is where almost every POH states full fine. I am as guilty of assumptions as anyone, but to me before landing means on final, not downwind.
As for annoying the neighbours.....
I reckon if they live near an airport, either they love the noise
Or they knew it was there when they moved in and so should put up or shut up.
Something we do agree on?
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Fantastic thread... I for one have learnt something (thanks Jaba!). I will "cherry pick" a few methods for future use!! The articles by John Deakin certainly filled a couple of gaps in my knowledge... these should be required reading as part of a CSU rating!!
I too have learnt a great deal (also thanks Jaba) and am now looking forward to some interesting conversations with some instructors on a trip I have coming up. Lets hope I dont get in to much trouble stirring the pot with my Deakin-ish, far left handed ways of preaching it is ok to fly over square!
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Turned out to be a thread packed with useful information. I think I have learnt more about engines from this than the CPL text.
I stumbled over this publication 'EGT and Combustion Analysis In A Nutshell' during my research that discuses the mixture control elements we have been discussing. Figured you can never have to much information
Again thanks to Jaba for his tutelage
I stumbled over this publication 'EGT and Combustion Analysis In A Nutshell' during my research that discuses the mixture control elements we have been discussing. Figured you can never have to much information
Again thanks to Jaba for his tutelage
If a commercial operator has to use the flight manual, why should a private pilot be taught not to?
Compliance with the Airplane Flight Manual, AFM (by whatever name) included as part of the aircraft certification documentation is required by law.
It doesn't make a blind bit of difference what license the pilot in command holds, or what kind of operation is being condusted, from private through HCRPT, the same rules apply. The AFM is NOT a list of guidelines, hard requirements must be adhered to.
Look at the strife Jetstar got into ( as well as getting within less than 100' of plowing in) over changing a missed approach procedure without the approval of the Type Certificate Holder and the certifying National Aviation Authority, NAA.
Non-compliance will invalidate any insurance policy, a far greater danger than CASA giving you a hard time.
For un-certified aircraft, if the engine manufacturer has solid recommendations, follow them.
If you are going to do a missed approach with other than full fine, be very very aware of the boost limits and aeroplane performance at the chosen power setting ---- and it is a procedure consistent with the AFM.
Tootle pip!!
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Katoom
That is a good article generally, but there is one paragraph that ruins it.
Now surely Mike has learned since 1995 that his thinking here is not based on proven test data. But a good article all the same if you ignore that one OWT 
.
Now the ALCOR article is interesting, I have not read it yet, and only scanned it, and spotted some OWT's in there too. Anyone else spot them? Chocky frog for the first three (not sure how many there are yet). Again possibly a good article but ruined with some pearlers of proven myths. I'll have a read later today, and see how well i stack up to all you eagle eye folk.
That is a good article generally, but there is one paragraph that ruins it.
Finally (but very importantly), lower RPMs produce lower EGTs at a given power output. At 65% cruise in my airplane, the EGT at 30"/2100 is more than 50F lower than the EGT at 26"/2350. This allows me to lean very aggressively (I cruise right at peak EGT) without the danger of over-temping my exhaust valves or cylinder heads. I wind up with a cleaner engine (fewer deposits on exhaust valve stems and spark plugs) plus better fuel economy.
.Now the ALCOR article is interesting, I have not read it yet, and only scanned it, and spotted some OWT's in there too. Anyone else spot them? Chocky frog for the first three (not sure how many there are yet). Again possibly a good article but ruined with some pearlers of proven myths. I'll have a read later today, and see how well i stack up to all you eagle eye folk.
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"Lean misfire" would be one (leave it at that so as no to be greedy).
Rather than the engine misfiring the fairly steep drop in HP once lean of peak can, when the injectors aren't balanced, create a large power difference between different cylinders.
One question I had regarding operating a lower RPM however. From my understanding the heat in an engine is related to the proximity of peak pressure and TDC. For a given EGT (so a given combustion speed right?) but a slower piston speed the peak pressure would occure closer to TDC, so causing a higher pressure and temperature. Is this somethign to be mindful of?
What change does CHT show with changes in RPM?
Rather than the engine misfiring the fairly steep drop in HP once lean of peak can, when the injectors aren't balanced, create a large power difference between different cylinders.
One question I had regarding operating a lower RPM however. From my understanding the heat in an engine is related to the proximity of peak pressure and TDC. For a given EGT (so a given combustion speed right?) but a slower piston speed the peak pressure would occure closer to TDC, so causing a higher pressure and temperature. Is this somethign to be mindful of?
What change does CHT show with changes in RPM?
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Ohhhhhh Dear!!! 
Sorry folks I have to retract that Chocky Frog offer........can't afford that many frogs
For what could have been a good article, and some of it was, it has been trashed.
So NIK320......be careful of all the good info out there....including mine
Aerozep, yes the PPP does move closer to TDC but at the typical RPM range 2100-2500 used in cruise power settings this is not an issue unless a minimum RPM is specified for your engine.
Setting 1700 maybe and a very high MP and a 50ROP mixture might get you pounding the piston right at TDC (you could work it out based on combustion time and ignition advance, but I am not keen to do that right now). That would be something to be concerned about.
Sorry folks I have to retract that Chocky Frog offer........can't afford that many frogs
For what could have been a good article, and some of it was, it has been trashed.
So NIK320......be careful of all the good info out there....including mine
Aerozep, yes the PPP does move closer to TDC but at the typical RPM range 2100-2500 used in cruise power settings this is not an issue unless a minimum RPM is specified for your engine.
Setting 1700 maybe and a very high MP and a 50ROP mixture might get you pounding the piston right at TDC (you could work it out based on combustion time and ignition advance, but I am not keen to do that right now). That would be something to be concerned about.
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T28D, we did mention MP, but compression ratio is a very good point indeed , although most Lyc/TCM's are all about the same, fairly low. Compression is done a few ways, and no doubt your namesake machine develops plenty of it via forced means .
This is where some of the dynamic ignition systems come into their own, but most GA engines are fixed.
we did mention MP, but compression ratio is a very good point indeed , although most Lyc/TCM's are all about the same, fairly low. Compression is done a few ways, and no doubt your namesake machine develops plenty of it via forced means .This is where some of the dynamic ignition systems come into their own, but most GA engines are fixed.
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Originally Posted by LeadSled
If you are going to do a missed approach with other than full fine, be very very aware of the boost limits and aeroplane performance at the chosen power setting ---- and it is a procedure consistent with the AFM.
Originally Posted by Jabawocky
Sorry folks I have to retract that Chocky Frog offer........can't afford that many frogs
Still more than the CPL text book has on it
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I see Mike learned a heap in the last 13 years I certainly did.
Have a read of this article compared to the 1995 one.
The Savvy Aviator #59: EGT, CHT and Leaning
I certainly did.Have a read of this article compared to the 1995 one.
The Savvy Aviator #59: EGT, CHT and Leaning
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The AFM is NOT a list of guidelines, hard requirements must be adhered to.
You say "the AFM must be adhered to". But what is the legal situation when the AFM is using words and phrases that are more akin to recommendations and advice, rather than concrete directives?
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You say "the AFM must be adhered to". But what is the legal situation when the AFM is using words and phrases that are more akin to recommendations and advice, rather than concrete directives?
You do something outside the AFM's 'Advice' and have a prang....thankfully you survive
It goes to court.
It turns out, that you were operating outside of the AFM's 'advice', but based on experience.
You are asked to show the documentation supporting your operating procedure.
Where do you stand now legally?
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actually, this touches on something i am very passionate about!
our Casa/caa/dot produced performance charts were pretty much the best in the world! but some legal muppet decided, that as they were not not produced by the manufacturer that CASA might get sued!
F*CK OFF!!!!!
So now we are expected to use the manufacturers documentation for p-charts..........we all know they are for best case scenario flown by test pilots......and we are also expected that to factor in the seppo's rules of thumb for slope, wind factors etc........ has casa sent us those guidlines? (still searching)
Casa produced p-charts include an error factor, for crap pilotage, aeroplane condition etc, and i have always managed to out perform them. I KNOW i can trust them to keep me safe.....can i do that for a rule of thumb?? and how would that rule of thumb stand up at my funeral?
Sad fact, POH's that still carry the CASA p-charts are now against the law, but we all know you can trust em.
over to the mob....
our Casa/caa/dot produced performance charts were pretty much the best in the world! but some legal muppet decided, that as they were not not produced by the manufacturer that CASA might get sued!
F*CK OFF!!!!!
So now we are expected to use the manufacturers documentation for p-charts..........we all know they are for best case scenario flown by test pilots......and we are also expected that to factor in the seppo's rules of thumb for slope, wind factors etc........ has casa sent us those guidlines? (still searching)
Casa produced p-charts include an error factor, for crap pilotage, aeroplane condition etc, and i have always managed to out perform them. I KNOW i can trust them to keep me safe.....can i do that for a rule of thumb?? and how would that rule of thumb stand up at my funeral?
Sad fact, POH's that still carry the CASA p-charts are now against the law, but we all know you can trust em.
over to the mob....
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jas24zzk, if you use the charts in the P.O.H and multiply by the factors required by CAO 20.7.4 (or applicable to your aircraft) you will have plenty of margin.