The dollars cost of reading written checklists.
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The dollars cost of reading written checklists.
While reminiscing about the good old days with a mate who flew Mustangs in the RAAF, the subject came up of written challenge and response checklists. In our era of the Fifties (RAAF) checklists were unheard of and all drills were done off by heart. The standard scan was left to right and it worked well.
Over the years, written checklists have become the norm at flying schools for light training types like the Cessna 172. Looking recently at the significant number of written checklist challenge and response items from start up to close down, used by some flying schools, it struck me that the cost in terms of time and therefore money taken to read from written checklists, is quite high.
Nowadays, six dollars per minute is a typical hiring rate dual for a Cessna single. Once the VDO starts running, it costs the average student at major general aviation airports, from engine start to the completion of line-up checks, roughly ten minutes of checklist reading. That's nearly sixty dollars gone down the drain challenging/responding to an instructor; or to himself if flying solo. And the aircraft is not even airborne yet...
It all adds up to the ever increasing expense of learning to fly - especially at the so-called "sausage machine" flying schools where students pay big money to become airline pilots of the future. Not only does blind reliance on lengthy and often superfluous written checklists cost the students money - but the unintended consequences of lengthy checklist reading has led to the situation where many students are uncertain of how to even start an engine without the crutch of a written checklist. This does not help a student's self confidence. To satisfy the pedants, perhaps the only written checklist should be a before take-off checklist, ruthessly culled to Vital Actions only, and omitting superfluous items that could be considered part of normal airmanship. And who decides what is normal airmanship? Now, there's the rub
Over the years, written checklists have become the norm at flying schools for light training types like the Cessna 172. Looking recently at the significant number of written checklist challenge and response items from start up to close down, used by some flying schools, it struck me that the cost in terms of time and therefore money taken to read from written checklists, is quite high.
Nowadays, six dollars per minute is a typical hiring rate dual for a Cessna single. Once the VDO starts running, it costs the average student at major general aviation airports, from engine start to the completion of line-up checks, roughly ten minutes of checklist reading. That's nearly sixty dollars gone down the drain challenging/responding to an instructor; or to himself if flying solo. And the aircraft is not even airborne yet...
It all adds up to the ever increasing expense of learning to fly - especially at the so-called "sausage machine" flying schools where students pay big money to become airline pilots of the future. Not only does blind reliance on lengthy and often superfluous written checklists cost the students money - but the unintended consequences of lengthy checklist reading has led to the situation where many students are uncertain of how to even start an engine without the crutch of a written checklist. This does not help a student's self confidence. To satisfy the pedants, perhaps the only written checklist should be a before take-off checklist, ruthessly culled to Vital Actions only, and omitting superfluous items that could be considered part of normal airmanship. And who decides what is normal airmanship? Now, there's the rub
Last edited by Centaurus; 3rd Jan 2013 at 12:17.
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Centaurus, as you well know, once the student leaves the GA mentality behind of certain training providers they are presented with a challenge....a challenge that you aptly describe in terms of having to re-learn skills that should have been taught from the beginning, i.e. a good robust methodology to learn and understand a scan flow.
I was fortunate, when I jumped into the C172 to learn to fly my instructor had already instilled a few simple pneumonics to help me get started..along with the flow and scan that went with it.
My favourite for a before takeoff scan/set up "To Many Flying Instructors Have Crashes"
But when I went elsewhere to do my MEIR..you should have seen the crap that was presented to me and used as a checklist....Jesus wept.
I was fortunate, when I jumped into the C172 to learn to fly my instructor had already instilled a few simple pneumonics to help me get started..along with the flow and scan that went with it.
My favourite for a before takeoff scan/set up "To Many Flying Instructors Have Crashes"
But when I went elsewhere to do my MEIR..you should have seen the crap that was presented to me and used as a checklist....Jesus wept.
In the P3 we have challenge/response checklists written by Mr Lockheed and it's 1000 items long. Not uncommon to get to the holding point at YPLM still doing checks then say "Alright now who the f-- is around here" with zero SA. A good example of the law of unintended consequences.
I went flying in a J model Herc and was very happy to see they got all the airline reservists in to give advice on how to do it properly. Their checklist only consisted of checking items that would kill you such as trims & flaps. It was a much simpler process and overall I think safer.
Keeping in mind that all these items are already done, we are just *checking* that they have been done. I'll also give credit that the J has much more automation of systems and has no flight engineer, but still, I dislike the philosophy of extra cx for the sake of it.
Example:
P3 Climb cx (from what I remember):
- Landing Gear up
- Flaps up
- Autofeather off
- Pressurisation set
- sync servo's normal
- sync master selected
- mws [as req]
J Herc climb cx
- Landing gear up
- Flaps up
I went flying in a J model Herc and was very happy to see they got all the airline reservists in to give advice on how to do it properly. Their checklist only consisted of checking items that would kill you such as trims & flaps. It was a much simpler process and overall I think safer.
Keeping in mind that all these items are already done, we are just *checking* that they have been done. I'll also give credit that the J has much more automation of systems and has no flight engineer, but still, I dislike the philosophy of extra cx for the sake of it.
Example:
P3 Climb cx (from what I remember):
- Landing Gear up
- Flaps up
- Autofeather off
- Pressurisation set
- sync servo's normal
- sync master selected
- mws [as req]
J Herc climb cx
- Landing gear up
- Flaps up
I've recently been tasked with creating Quick Reference Handbooks at my current job and part of that of course is putting in the Checklists for each aircraft.
I've never done this before and have of course relied in other jobs on the ones provided to me which have been generally quite concise and others have pointed out consisted of mostly just the Vital Actions.
Did a little research and came across this gem http://ti.arc.nasa.gov/m/profile/ade...Checklists.pdf its a great read on what makes good checklists and what makes bad ones. As they pointed out superflous items or items that are often repeated make for bad checklists as people tend to start glazing over them which of course defeats the purpose of a checklist!!
I should point out i'm personally talking about your ordinary "CHECK"List as opposed to the Challenge and Response ones that larger airlines use and find that these work great in the smaller aircraft and what are what I was taught to use in my own training.
In my own task I took Mr Cessnas checklists straight from the POH, then sat in the aircraft and did my own checklists based on mnemonics i'd been taught since training and put these together to make them checklists that followed the usual figure 4 flow and covered all the essential items in their basic categories.
So far they seem to work quite well!
I've never done this before and have of course relied in other jobs on the ones provided to me which have been generally quite concise and others have pointed out consisted of mostly just the Vital Actions.
Did a little research and came across this gem http://ti.arc.nasa.gov/m/profile/ade...Checklists.pdf its a great read on what makes good checklists and what makes bad ones. As they pointed out superflous items or items that are often repeated make for bad checklists as people tend to start glazing over them which of course defeats the purpose of a checklist!!
I should point out i'm personally talking about your ordinary "CHECK"List as opposed to the Challenge and Response ones that larger airlines use and find that these work great in the smaller aircraft and what are what I was taught to use in my own training.
In my own task I took Mr Cessnas checklists straight from the POH, then sat in the aircraft and did my own checklists based on mnemonics i'd been taught since training and put these together to make them checklists that followed the usual figure 4 flow and covered all the essential items in their basic categories.
So far they seem to work quite well!
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John Deakin wrote a column back in the 1990s that recommended a similar approach: Throw Away That Stupid Checklist! and followed it up with Checklists Redux
Seemed to make a lot of sense to me, worked well for the mix of PA28s, Citabrias, BE76s and Partbananas I was flying at the time ....
Seemed to make a lot of sense to me, worked well for the mix of PA28s, Citabrias, BE76s and Partbananas I was flying at the time ....
Long winded checklists have been my pet-hate for years.
Boeing 744 Pre-Take Off..............Flaps 20. ( flight controls, hydraulics and fuel configuration all done before start and the trims with the load sheet etc). Wonderful.
Beech 76 at local flying school. Pre-take Off.......27 items!! (and no less than 61 items in the pre-start) . Distracting rubbish, encouraging heads in cockpit and complete loss of situation awarness. One Pre-Take Off item is 'circuit breakers', they should be pre-flight, not taxiing out.
Boeing 744 Pre-Take Off..............Flaps 20. ( flight controls, hydraulics and fuel configuration all done before start and the trims with the load sheet etc). Wonderful.
Beech 76 at local flying school. Pre-take Off.......27 items!! (and no less than 61 items in the pre-start) . Distracting rubbish, encouraging heads in cockpit and complete loss of situation awarness. One Pre-Take Off item is 'circuit breakers', they should be pre-flight, not taxiing out.
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Centaurus
Once again you have hit the nail on the head. I see this at our airfield with one school, every flight.
What is worse, most of them sit there for hours with the damned mixture knob all the way in. I have seen the results of this on not just plugs and cylinders but fuel control units as well. Go to YPPF if you need to see it forst hand.
And then add to this....when they return
More damned checklists. My engine is OFF within several seconds of pulling up at the hangar, every time!
Stop now Jaba......
Once again you have hit the nail on the head. I see this at our airfield with one school, every flight.
What is worse, most of them sit there for hours with the damned mixture knob all the way in. I have seen the results of this on not just plugs and cylinders but fuel control units as well. Go to YPPF if you need to see it forst hand.
And then add to this....when they return
More damned checklists. My engine is OFF within several seconds of pulling up at the hangar, every time!Stop now Jaba......
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Given their experience in operating aircraft the USAF in general have a quite reasonable approach to this subject.
Simple example the T 28 a training aircraft in most of its models has the pre takeoff list on the left of the panel next to the U/C selector and the pre landing list on the right of the panel next to the manifold pressure, 6 items on each list.
Simple example the T 28 a training aircraft in most of its models has the pre takeoff list on the left of the panel next to the U/C selector and the pre landing list on the right of the panel next to the manifold pressure, 6 items on each list.
And who decides what is normal airmanship?
The idea that students need to learn airline style checklists because they don't have the capacity to adapt to different styles of checklist as they go through their flying career is a symptom of this and underestimates the intelligence of pilots.
Fundamentally the checklist is about configuring the aircraft for its mode of flight as recommended by the manufacturer. Nothing more. The appropriate checklist & check routine depends on the type of aircraft and type of flight. Making this determination is airmanship. The required check regime for a non electric J3 cub bears little in common with that for an IFR take-off in a complex twin. I'm pretty sure that B747 captain who owns a J3 doesn't follow the airline routine on a Sunday morning.
Check lists should be situational. The checklist (or correctly to-do-list) that I do in the twin is different for a VFR flight around the bay than it is an IFR plan flight which is different than a one with a take-off into IMC. The around the bay flight doesn't need much more than fuel-mixture-switches and the only instruments I really need to get back safely are airspeed & altitude. A flight with an expectation of IFR gets full autopilot, instrument and engine checks.
Some time ago, I became interested in flow checks. I read on the subject, got cockpit photos and reconstructed all the checklists to conform with the flow pattern. Even drew lines around the cockpit that followed the flow. It was a thing of beauty, but for single pilot GA operation, nearly unworkable and by no means transferable between aircraft. I never used it.
The beauty of the old simple memorised "to-do"list is that it can be used on anything up to about a pressurised twin. The bit that needs to be added is the airmanship element of thinking forward about the flight and changing the emphasis or adding additional sub-routines.
In Australia TMPFISCH is common. In America it is CIGAR. Neither fully conform with POH's, but they have been successfully used for 50 years or more. They have been used successfully and safely long before the advent of safety committees. How hard do we need to make things?
How do you determine a level of airmanship? I suspect this rests in the pilots answer to why he is choosing to do a particular thing. Any answer that involves because it is on the checklist or in the rules deserves a slap. My concern is that we now have not only students but also instructors that could not do this. My allied concern is that we have multiple generations of students and instructors who have only flown Piper or Cessna nosewheel aircraft in normal flight. This is a very narrow slice of the flight experience.
Returning to the initial question, is it a waste of money? - maybe. But only in the school environment. Hardly anyone else charges by VDO time. Its certainly not the basis for maintenance. In a turbocharged aircraft, I do as much as I can with the engines running because it warms them more gently and is kind to them. 10 - 15 minutes of ground running is good.
PS, nice reference Ixixly
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In our era of the Fifties (RAAF) checklists were unheard of and all drills were done off by heart. The standard scan was left to right and it worked well.
Although in my opinion we make the students learn way too many checks, especially in the CT4.
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Neither fully conform with POH's,
So when you see instructors and students harping on about it does not say you can do this or that in the POH, think again carefully. Ask them the question! Like walking into a bar and starting a fight and walking off
From the C150 that I learnt to fly 40 years ago to the C402 that was the pinnacle of my GA career, I have survived on:
T M P F F I H C L
Seems to cover what will kill you!
Dr
T M P F F I H C L
Seems to cover what will kill you!
Dr
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10 - 15 minutes of ground running is good.
While there may well be optimum limits for turbo-charging "warm-up" I suggest that 15 minutes of ground running time simply to give optimum turbo-charge conditions is a myth. The other thing to keep in mind is that as CHT increases during normal ground operation because of absence of efficient cooling airflow, it results in less power being available for take off and climb. This becomes quite important when considering the already low rate of climb after engine failure on most light piston twins
All pilots should study John Deakin's articles on engine handling. They are the best you will find IMHP.
Last edited by Tee Emm; 4th Jan 2013 at 03:51.
On every type I flew except one (Caribou), we used memory checks with a flow pattern for the routine stuff, memory checks followed by checklist backup when time permitted for emergencies. I have always much preferred the memory stuff.
Rote learning by looking at cockpit photos and testing yourself from the checklist takes a bit of time and practice, but it's very effective, and I'd argue just as accurate as challenge and response if you put the work in, not to mention lets you keep your attention more on flying the aeroplane when it counts rather than having your head buried in a book.
PS Haughtney, sorry, but I am duty bound to correct this one whenever I see it (pneumonics are drugs used to treat pneumonia; mnemonics are the things you're talking about!
)
Rote learning by looking at cockpit photos and testing yourself from the checklist takes a bit of time and practice, but it's very effective, and I'd argue just as accurate as challenge and response if you put the work in, not to mention lets you keep your attention more on flying the aeroplane when it counts rather than having your head buried in a book.
PS Haughtney, sorry, but I am duty bound to correct this one whenever I see it (pneumonics are drugs used to treat pneumonia; mnemonics are the things you're talking about!
)
my instructor had already instilled a few simple pneumonics to help me get started
'Forkie' I still use "PUFF" prior to Ldg after all the normal check lists have been done..........some things are ingrained I guess
I personally don't see too much harm in chk lists,(mainly 'cause in my GA days I flew multiple types for multiple operators at times months apart) they are after all 'check' lists of items that are already done.
Someone mentioned CB's in a Chk list that where checked prior to star having had to be checked again. Fair enuf I can see the reasoning behind that to some degree(not checking them again) but in old planes these days a CB could easily trip/pop after they where originally checked so do it a 1000 times & find zip (which is great that's what we want) do it 1001 times & find the U/C CB popped due an elect spike (anyone's guess), better to chk for if nothing else POM:-)
Wmk2
I personally don't see too much harm in chk lists,(mainly 'cause in my GA days I flew multiple types for multiple operators at times months apart) they are after all 'check' lists of items that are already done.
Someone mentioned CB's in a Chk list that where checked prior to star having had to be checked again. Fair enuf I can see the reasoning behind that to some degree(not checking them again) but in old planes these days a CB could easily trip/pop after they where originally checked so do it a 1000 times & find zip (which is great that's what we want) do it 1001 times & find the U/C CB popped due an elect spike (anyone's guess), better to chk for if nothing else POM:-)
Wmk2
Last edited by Wally Mk2; 4th Jan 2013 at 02:38.
Tee-Emm
What % power do you think an engine produces at idle? I'm not sure, but I'd be guessing 5%. The cooling task is not all that big at this power level.
Typically the air - pressure differential between the top and bottom of the engine is 4psi or less. Engines don't need ram air for cooling - that's why there is the modern trend for small inlets. In fact the turbo Lance does not have forward facing air inlets at all. I have yet to see CHT's get to the green zone during warm up.
The key thing to warm is the cylinders and oil not the turbocharger. The reason that turbo engines are more critical is that they run at higher BMEP's and turbo lubrication is important for turbo life. The thing you are trying to do is prolong the time before the (Continental) cylinders go barrel shaped. One of the weaknesses of air cooled engines is uneven temperature distribution. The water cooled cars we drive are much more tolerant. Except for my old dry-sumped cars, I turn the key and go in my cars.
Also aircraft still use single grade oil. So there is a bigger variation in viscosity between hot & cold than car oil. You really want to get the oil warm so that it is able to provide the proper hydrodynamic lubrication to the bottom end and turbo. The top end relies more on boundary lubrication, so oil flow here is less critical. How long do you think it takes to raise the temperature of maybe 8 litres of oil by (say) 50 degC? At operating temperature Phil Irving suggests that as much as 10% of engine cooling is performed by the oil, so the initially cold oil has a significant cooling effect on the engine also. The optimal operating oil temperature is about the same was car water temperature - 90 - 130 degC. In cars, oil typically runs about 10 degC hotter than water temp. High temperature breaks down the oil and shortens its life. Low temperature compromises the ability to have a thin film for bearing lubrication. It is said that the pumping effect of the rotating crankshaft on the bearing creates local oil pressure in excess of 5,000 psi! There is also value in getting the oil hot enough to burn off volatile fuel residue and condensation before the engine has serious load.
One of the debating points is at what RPM the engine should be warmed. Tony Brand maintains that it should be at idle (500 -800 rpm) rather than the practice we are taught of 1,000 rpm. Phil Irving contends that the engine speed should be fast enough to create splash lubrication to the cylinder bores and underside of the piston. I think both views have merit, but I find there is too much problem with plug fouling at idle speeds. So I stick to the POH recommendation of 1,000 rpm.
In my aeroplane I find that cowl flaps are not usually required on the ground or on initial climb. It is extended climb and flight level operation at temperatures above ISA where I need them to help manage CHT. This fits the POH which has no instruction on the use of cowl flaps other than to maintain desired CHT's.
On shutdown there is value in letting the turbo's cool. That's an issue about turbo bearing temperature and bearing life more than impeller or body temperature. Although, if I get to fly the approach I want (rather than having it modified by ATC), then by the time the aircraft has landed and taxied its been at low power settings long enough to not be an issue. I open cowl flaps before shutdown to help dissipate heat soak.
John Deakins writes some very good things, but there some OWT's that he replaces with new wives tales. And you need to remember that he has a financial link with GAMMI. The better thing to do is read the references he cites. He actually makes that point quite strongly, but its not often recognised. Beyond that Phil Irving's book is still a classic and there is still a lot to be learned from Sir Harry Ricardo's original book. The best stuff I've learned about turbo's has come from the 2 guys that used to build the engines for the Nissan works racing GTR's.
This is a bit of a thread drift and a it of a rant, sorry. But there is a lot of value in warming engines that charging by VDO time discourages. I suspect that flying schools get through engine time fast enough for it not to be so much of a concern as it is to private owners.
What % power do you think an engine produces at idle? I'm not sure, but I'd be guessing 5%. The cooling task is not all that big at this power level.
Typically the air - pressure differential between the top and bottom of the engine is 4psi or less. Engines don't need ram air for cooling - that's why there is the modern trend for small inlets. In fact the turbo Lance does not have forward facing air inlets at all. I have yet to see CHT's get to the green zone during warm up.
The key thing to warm is the cylinders and oil not the turbocharger. The reason that turbo engines are more critical is that they run at higher BMEP's and turbo lubrication is important for turbo life. The thing you are trying to do is prolong the time before the (Continental) cylinders go barrel shaped. One of the weaknesses of air cooled engines is uneven temperature distribution. The water cooled cars we drive are much more tolerant. Except for my old dry-sumped cars, I turn the key and go in my cars.
Also aircraft still use single grade oil. So there is a bigger variation in viscosity between hot & cold than car oil. You really want to get the oil warm so that it is able to provide the proper hydrodynamic lubrication to the bottom end and turbo. The top end relies more on boundary lubrication, so oil flow here is less critical. How long do you think it takes to raise the temperature of maybe 8 litres of oil by (say) 50 degC? At operating temperature Phil Irving suggests that as much as 10% of engine cooling is performed by the oil, so the initially cold oil has a significant cooling effect on the engine also. The optimal operating oil temperature is about the same was car water temperature - 90 - 130 degC. In cars, oil typically runs about 10 degC hotter than water temp. High temperature breaks down the oil and shortens its life. Low temperature compromises the ability to have a thin film for bearing lubrication. It is said that the pumping effect of the rotating crankshaft on the bearing creates local oil pressure in excess of 5,000 psi! There is also value in getting the oil hot enough to burn off volatile fuel residue and condensation before the engine has serious load.
One of the debating points is at what RPM the engine should be warmed. Tony Brand maintains that it should be at idle (500 -800 rpm) rather than the practice we are taught of 1,000 rpm. Phil Irving contends that the engine speed should be fast enough to create splash lubrication to the cylinder bores and underside of the piston. I think both views have merit, but I find there is too much problem with plug fouling at idle speeds. So I stick to the POH recommendation of 1,000 rpm.
In my aeroplane I find that cowl flaps are not usually required on the ground or on initial climb. It is extended climb and flight level operation at temperatures above ISA where I need them to help manage CHT. This fits the POH which has no instruction on the use of cowl flaps other than to maintain desired CHT's.
On shutdown there is value in letting the turbo's cool. That's an issue about turbo bearing temperature and bearing life more than impeller or body temperature. Although, if I get to fly the approach I want (rather than having it modified by ATC), then by the time the aircraft has landed and taxied its been at low power settings long enough to not be an issue. I open cowl flaps before shutdown to help dissipate heat soak.
John Deakins writes some very good things, but there some OWT's that he replaces with new wives tales. And you need to remember that he has a financial link with GAMMI. The better thing to do is read the references he cites. He actually makes that point quite strongly, but its not often recognised. Beyond that Phil Irving's book is still a classic and there is still a lot to be learned from Sir Harry Ricardo's original book. The best stuff I've learned about turbo's has come from the 2 guys that used to build the engines for the Nissan works racing GTR's.
This is a bit of a thread drift and a it of a rant, sorry. But there is a lot of value in warming engines that charging by VDO time discourages. I suspect that flying schools get through engine time fast enough for it not to be so much of a concern as it is to private owners.
On engine warming: When the oil temperature is at the bottom of the green GO! My little Sonex is tightly cowled and on a hot day I am airborne within 5 minutes of start up from cold. If I were to sit on the ground for 15 minutes the cylinder temps would be almost at redline. At 20 minutes I would have to shut it down and walk away for a couple of hours to let it cool down.
Back to checklists: A major problem is the way that the CAR requires CASA to 'approve' checklists. There is no standard CASA policy - what you can slip past one FOI can be sh!tcanned by another. Many is the battle I have had to remove non essential crap from checklists.
The best approach I ever saw was in a B 737 manual published by United Airlines. At the very beginning of the book it said words to the effect of
"Procedures and checklists in this Manual have been compiled as a result of many years' experience operating the aircraft. In some cases these instructions may diverge from the manufacturer's procedures and checklists. In such cases UAL accepts full responsibility and liability for any changes"
Now, obviously the FAA made them do that. Also, obviously, they would not change stuff without a very thorough risk analysis first.
Operators here should be allowed similar policies.
Back to checklists: A major problem is the way that the CAR requires CASA to 'approve' checklists. There is no standard CASA policy - what you can slip past one FOI can be sh!tcanned by another. Many is the battle I have had to remove non essential crap from checklists.
The best approach I ever saw was in a B 737 manual published by United Airlines. At the very beginning of the book it said words to the effect of
"Procedures and checklists in this Manual have been compiled as a result of many years' experience operating the aircraft. In some cases these instructions may diverge from the manufacturer's procedures and checklists. In such cases UAL accepts full responsibility and liability for any changes"
Now, obviously the FAA made them do that. Also, obviously, they would not change stuff without a very thorough risk analysis first.
Operators here should be allowed similar policies.
Last edited by Mach E Avelli; 4th Jan 2013 at 03:25.
Can't decide whether to have a go at the Sonex or not! But seriously, I think it has a lot to do with engine mass & oil volume (3.5 litre capacity is small comparted with Lyc or Cont). The Jabiru engine gets about 20% more power than the equivalent Lyc or Continental. So its clearly a more efficient, more highly stressed (not meant in a bad way) engine.
With apologies for the thread drift, but I think being able to use multi grade oil allows for much more rapid warm ups in Jabiru powered aircraft, as opposed to say the P&W 1830s in a DC3 where I seem to recall it took quite a while to get everything into the green on the first flight of the day. Plenty of time for intricate run ups, bleeding auto pilot hydraulics, feathering props etc.
And we did it all without a checklist!
And we did it all without a checklist!
Operators here should be allowed similar policies.
For current transport category aircraft, as a general rule, the manufacturer knows best. Why would you operate it any other way?
Last edited by compressor stall; 4th Jan 2013 at 04:24.
