Flying over square
I'll concur with GB. Same in my 210.
WOT for climb and leave it there, just pulling it back on descent to avoid the yellow.
I too don't richen for descent.
Sure go full fine on very short final if you want as by then the prop is out of governing range and won't make any noise to scare the locals !!
WOT for climb and leave it there, just pulling it back on descent to avoid the yellow.
I too don't richen for descent.
Sure go full fine on very short final if you want as by then the prop is out of governing range and won't make any noise to scare the locals !!
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Obviously no round engine pilots here, Wright 1820-86 take off 2700 rpm 52.5 inches climb 2400/36 inches economical cruise 2000/30 inches approach 1800/20 inches go round 2400/36 inches
Pratt Wasp Junior take off 36/2300 climb 31/2100 cruise 29/1850 approach 20/1850 go around 31/2100.
Oversquare ?????
Pratt Wasp Junior take off 36/2300 climb 31/2100 cruise 29/1850 approach 20/1850 go around 31/2100.
Oversquare ?????
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T28D
I know you will be pleased if not alarmed to hear me say 100% agree
The fuel does not know the difference. It just combusts all the same given the same circumstances, be it round or not!
J
I know you will be pleased if not alarmed to hear me say 100% agree
The fuel does not know the difference. It just combusts all the same given the same circumstances, be it round or not!
J
It does seem that some people here are advocating landing with the prop at the descent setting (correct me if I'm wrong).
If you don't slam the pitch into full fine while carrying Vref + say 30kts, you won't get the prop bouncing off the redline while it attempts to govern your hamfisted commands.
Pitch max will also provide a very useful source of drag to provide that last bit of deceleration over the fence and give you the best climb ability in the event of a go-around.
During a go-around, why wouldn't you maximise your RoC by using T/O power? Height is your friend. Get it ASAP! Once a a safe height, then use the max cont. pwr settings (which most likely are your baulked landing figures....coincidence?)
If you don't slam the pitch into full fine while carrying Vref + say 30kts, you won't get the prop bouncing off the redline while it attempts to govern your hamfisted commands.
Pitch max will also provide a very useful source of drag to provide that last bit of deceleration over the fence and give you the best climb ability in the event of a go-around.
During a go-around, why wouldn't you maximise your RoC by using T/O power? Height is your friend. Get it ASAP! Once a a safe height, then use the max cont. pwr settings (which most likely are your baulked landing figures....coincidence?)
If you've got the power back far enough, which you should on short final, the propeller will already be up on the fine pitch stops, and therefore no movement of the RPM control towards high rpm, be it a slow gentle movement or a ham-fisted shove, will actually change the blade angle or RPM at all.
If you've got the power up so high that you're still in the governing range, then you're too fast on final.
Easy test to see if the propellor is on the fine pitch stops - is it still on the same RPM you set in cruise? If its any less at all, then you've got yourself a propeller on the fine pitch stops already. No change in noise, no change in descent rate, no change in drag from here.
If you've got the power up so high that you're still in the governing range, then you're too fast on final.
Easy test to see if the propellor is on the fine pitch stops - is it still on the same RPM you set in cruise? If its any less at all, then you've got yourself a propeller on the fine pitch stops already. No change in noise, no change in descent rate, no change in drag from here.
Grandpa Aerotart
I remember once doing bumps and goes with a very experienced testing officer and having the RPM set at 2200 rpm (in a C206) and just using the throttle in the normal way but never exceeding the green arch of the MP. The aircraft preformed well and with no noticeable issues.
The single kindest thing you can do to a piston engine is use FULL rated power on every takeoff.
multime what is the essential difference between a Lyc and a Conti, radial or turbo?
I suggest to you there is no real difference in how they function or their metallurgy.
Sure, some have METO limits but MANY don't.
Treating those that don't like they do is actually bad for them.
A lot of people talk about MP and RPM as if they are the be all and end all - not true. Mixture is enormously important - and usually the least well understood.
I have spent LOTS of hours in my Bonanza tooling around with the IO550b at 27 or 28 inches MP, RPM at 2200 and mixture 30F LOP EGT. The engine loves it - it runs cool and clean with low CHTs and internal cylinder pressures. You could happily operate the engine that way for 1000s of hours.
IF I was so stupid as to move the mixture to 30F ROP EGT, and change nothing else, I would likely ruin the engine in no time flat. At the very least I would cook the cylinders in a few hundred hrs - worst case I could set off detonation and have the engine fail catastrophically in minutes.
And all I touched was the red knob.
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Pitch max will also provide a very useful source of drag ...
Is it producing that drag at the same time as it is producing thrust?
Was it the act of "increasing pitch" that caused it to start producing drag?
On takeoff, the blades will initially be on the fine pitch stops, but will move off the stops as the airspeed starts to build. Is the prop producing drag during these stages? Or is it producing thrust?
Is it producing that drag at the same time as it is producing thrust?
Was it the act of "increasing pitch" that caused it to start producing drag?
Slightly off topic but I am led to believe that having the airflow drive-on the engines is very, very bad for GTSIO engines.
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It does seem that some people here are advocating landing with the prop at the descent setting (correct me if I'm wrong).
If you don't slam the pitch into full fine while carrying Vref + say 30kts, you won't get the prop bouncing off the redline while it attempts to govern your hamfisted commands.
Pitch max will also provide a very useful source of drag to provide that last bit of deceleration over the fence and give you the best climb ability in the event of a go-around.
During a go-around, why wouldn't you maximise your RoC by using T/O power? Height is your friend. Get it ASAP! Once a a safe height, then use the max cont. pwr settings (which most likely are your baulked landing figures....coincidence?)
If you don't slam the pitch into full fine while carrying Vref + say 30kts, you won't get the prop bouncing off the redline while it attempts to govern your hamfisted commands.
Pitch max will also provide a very useful source of drag to provide that last bit of deceleration over the fence and give you the best climb ability in the event of a go-around.
During a go-around, why wouldn't you maximise your RoC by using T/O power? Height is your friend. Get it ASAP! Once a a safe height, then use the max cont. pwr settings (which most likely are your baulked landing figures....coincidence?)
I am really not sure you understand what you are trying to say here. Why not land with the pitch control still set from the cruise. say 2300 RPM. Why not, in the event of a baulked landing, RED/BLUE/BLACK, in about the time you read that, or if you can do all at the same time, who cares. It will not make any difference. Now you are climbing away at full bore max rate.
In the likely event that you land, and I am sure you do mostly, taxi away leaned out, and not clogging up everything.
If you really do need all that extra drag from pitch, well use it, but next time plan your approach better
. As pointed out already once the power is off the prop will be fine anyway so if you really want to move the lever up. There is no reason not to. But just the same there is no valid reason to.Just as Chuckles is not surprised about testing officers, I am not surprised but still alarmed at how many CPL's are being churned out with all these OWT's well drilled into them. Hey Pyro
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I don't touch the props on landing. Sometimes on shorter strips I might just ease them forward a bit, but that's about it.
I run my geared engines (which is a different kettle of fish admittedly) at 20" and 2500rpm all day. I'll reduce the manifold as I descend to keep the 20" going as I get lower, and then go to even lower settings for the circuit as needed.
I run my geared engines (which is a different kettle of fish admittedly) at 20" and 2500rpm all day. I'll reduce the manifold as I descend to keep the 20" going as I get lower, and then go to even lower settings for the circuit as needed.
I am not surprised but still alarmed at how many CPL's are being churned out with all these OWT's well drilled into them.
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Spyderpig
I have no idea why....because when we are taught and I was a victim of this, we trust almost implicitly everything this font of all knowlege is teaching us.
My driving instructor when I was 17 was a good example, however the race training showed me much better skills.
So why do things get passed through generations, because it seems to be human nature. I believed a lot of this stuff until I saw the light, thought about it with an engineering type mindset, and then went and played in the air, and low and behold I saw with my own eyes
I had been misled for so long.
Now I am like one of those born again evangalistic LOP'ers
.
The truth shall set you free!
I think one of the other reasons is most instructors now and 30 years ago had no idea on the science, did not have a clue about how to work it out for themselves and back then communications was not like today where information is a blink away no matter where you are.
The old raial piston airliner guys knew and operated differently to what most kids are being taught today, and some of the Rules of Thumb from back then were applied to modern flat 4/6's without only part of the rule applied. The oversquare one is a classic example.
Now if young Pyro were brave enough to pop up here he would tell you the day he convincingly told me why you should fly a C172 RG a certain way. I challenged him on why he thought that. The answer was ...well politely put...Bull****, and I hope when a scientific explanation was put forward it sunk in and he did not revert to old habbits. He understood the common sense at the time, the theory I told him actually worked in the air, and the aircraft performed better ran cooler etc etc..........but I have to wonder have OWT's krept back into his SOP?
Maybe another session or two is required to cure the brainwashing. I call it brain flushing.
Why did the pwople back hundreds of years ago fear and believe the world was flat despite some sailors thinking and proving otherwise? GA training is no different.
J
I have no idea why....because when we are taught and I was a victim of this, we trust almost implicitly everything this font of all knowlege is teaching us.
My driving instructor when I was 17 was a good example, however the race training showed me much better skills.
So why do things get passed through generations, because it seems to be human nature. I believed a lot of this stuff until I saw the light, thought about it with an engineering type mindset, and then went and played in the air, and low and behold I saw with my own eyes
I had been misled for so long.Now I am like one of those born again evangalistic LOP'ers
.The truth shall set you free!
I think one of the other reasons is most instructors now and 30 years ago had no idea on the science, did not have a clue about how to work it out for themselves and back then communications was not like today where information is a blink away no matter where you are.
The old raial piston airliner guys knew and operated differently to what most kids are being taught today, and some of the Rules of Thumb from back then were applied to modern flat 4/6's without only part of the rule applied. The oversquare one is a classic example.
Now if young Pyro were brave enough to pop up here he would tell you the day he convincingly told me why you should fly a C172 RG a certain way. I challenged him on why he thought that. The answer was ...well politely put...Bull****, and I hope when a scientific explanation was put forward it sunk in and he did not revert to old habbits. He understood the common sense at the time, the theory I told him actually worked in the air, and the aircraft performed better ran cooler etc etc..........but I have to wonder have OWT's krept back into his SOP?
Maybe another session or two is required to cure the brainwashing. I call it brain flushing.
Why did the pwople back hundreds of years ago fear and believe the world was flat despite some sailors thinking and proving otherwise? GA training is no different.
J
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BUT - if I rocked up to my flying school and started using my own techniques, i'd probably be branded an idiot that is abusing the aircraft...
I even once had an instructor yell at me that I was "overboosting" a naturally aspirated engine because I was running at 24" MP and 2300rpm... Obviously this is a crock of bull****, but with me as a PPL and the bloke yelling at me was a grade 2 instructor, what the hell would I know!?!?!?!
I even once had an instructor yell at me that I was "overboosting" a naturally aspirated engine because I was running at 24" MP and 2300rpm... Obviously this is a crock of bull****, but with me as a PPL and the bloke yelling at me was a grade 2 instructor, what the hell would I know!?!?!?!
Anyway the best question is .....Why would you say that? Followed up with really, now have you considered the science behind...........etc. Unfortunately some ego's will need a little massaging and you cant call them a turkey to their face, all you can do is educate them with more advanced technology....one day they will realise they were sold a pup once too! I know I was.
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The training environment is in my experience fairly insulated from the outside world. Most people at the top have done little else, and most junior instructors (myself included) have learnt everything from those at the top.
I too was told off for "over boosting" at 24.5/2400rpm. I bet if I'd been at the 24.8/2100rpm the power chart for that aircraft recomended for 65% power at that altitude they would have had a heart attack. Of course, at that point in time I flew as per the flying schools SOPs: 25/2500 for climb, 24/2400 for cruise, 1" reduction per min (shock cooling BS), full rich at TOD. What a load of rubbish.
Interstingly, from my understanding the radial advice was to never run UNDER "squared" in the misguided attempt to avoid the prop driving the engine. John Deakin has a good article on this, and how it possibly lead to the loss of a CAF Heinkel 111.
Anyway, quite simply many/most pilots are ignorant of the fact they are ignorant. Flight instructors being amongst the worst, and the most dangerous. If a PPL doesn't know how to run their aircraft, they're the only ones being put in danger. If a instructor doesn't, they're passing that on to so many others.
I've shown the graph of EGT/CHT/ICP/HP to people and it blows their minds. The idea that it is high CHT/ICP that causes detonation not "over-boosting" or "over-leaning" takes a long time to be believed.
I think its criminal that it isn't more widely known. This ignorance has killed people, and will continue to kill people.
*prays at the alter of Deakin*
I too was told off for "over boosting" at 24.5/2400rpm. I bet if I'd been at the 24.8/2100rpm the power chart for that aircraft recomended for 65% power at that altitude they would have had a heart attack. Of course, at that point in time I flew as per the flying schools SOPs: 25/2500 for climb, 24/2400 for cruise, 1" reduction per min (shock cooling BS), full rich at TOD. What a load of rubbish.
Interstingly, from my understanding the radial advice was to never run UNDER "squared" in the misguided attempt to avoid the prop driving the engine. John Deakin has a good article on this, and how it possibly lead to the loss of a CAF Heinkel 111.
Anyway, quite simply many/most pilots are ignorant of the fact they are ignorant. Flight instructors being amongst the worst, and the most dangerous. If a PPL doesn't know how to run their aircraft, they're the only ones being put in danger. If a instructor doesn't, they're passing that on to so many others.
I've shown the graph of EGT/CHT/ICP/HP to people and it blows their minds. The idea that it is high CHT/ICP that causes detonation not "over-boosting" or "over-leaning" takes a long time to be believed.
I think its criminal that it isn't more widely known. This ignorance has killed people, and will continue to kill people.
*prays at the alter of Deakin*
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Some very interesting and informative posts on this subject, nice to see a healthy discussion taking place.
A lot of different opinions on leaning procedures and which is best, maybe time for a thread on LOP v ROP or would that just be opening up a can of worms??
Knox.
A lot of different opinions on leaning procedures and which is best, maybe time for a thread on LOP v ROP or would that just be opening up a can of worms??
Knox.