Take Off Flaps - 210

[gaunty]

29.5in MP by itself means absolutely nothing

= true but I don't believe anybody here thought otherwise, excellent explication nonetheless .
The point of my question was very simple, how do you know that the indicated MAP apart from, being "up" there is what it should be, unlike the FF and RPM gauges there are no "red line" or "absolute" markings on the instrument beyond a measure of indicated pressure.

As for your RPM and FF "adjustments"

but the engine is cooler and less stressed internally

does not necessarily follow, it may be cooler but not less stressed, piston speeds and centrifugal forces are higher and loads increase as a square function. The "redlines" are there for a very good reason and "certified" to be so. By going outside the boundaries specified by the manufacturer you are going into whatever buffer area there might be. I dont know what the buffer area is any more than you, but it is part of a rational engineering certification process not guesswork.

For the same reason you calculate N1 for TO, which is usually well within the Temp limits, why wouldn't you crack on another 1% (same as 25/2500 RPM) on just for good measure. Because that is the thrust to which the engine/ airframe and performance is certified to and we are talking about routine ops here.

[Chimbu chuckles]

Disagree with you on that...the same engine/prop combination on a C210 has a 2850 RPM redline so I am not worried about 2730ish...neither is the engineer who adjusted it and test stand data from Gami supports the point that a little over redline is much better than a little under in this area. It only became obvious that the prop wasn't reaching 2700RPM on takeoff when I replaced the original fit tacho with a digital one a few years ago...I was getting 2650ish on takeoff and the full power fuel flow was a little on the low side too...and the CHTs were hotter than they should have been.

Adjusting the prop to achieve at least redline RPM on takeoff spun the engine driven fuel pump a little quicker and gave me the correct 'redline'(+ a bit) fuel flow too.

The CHTs on the first takeoff after adjustment were a good 15C cooler than before...less heat is a VERY good thing.

The science behind why it is so and why it is better than just under redline for these two parameters has to do with where the piston is during the peak power pulse and ensuring the mixture is rich enough.

These engines have fixed timing...that is the spark occurrs at a specific point before TDC so that the peak power pulse occurrs at the right point after TDC to apply the maximum push on the piston.

On takeoff if you are not achieving redline RPM the piston will be closer to TDC when the burning fuel/air mixture is applying the most pressure...the peak power pulse. The combustion chamber (the volume in the cylinder above the piston) will be smaller than ideal and because of the rotational physics of the piston/conrod/crankshaft combo will be getting 'bigger' at a slower (but accelerating) rate. Because that fuel/air mixture is burning in a smaller combustion chamber it is applying much more pressure to the cylinder head and the maximum 'push' on the piston is occurring at a less efficient point in the crankshaft rotation so you're getting less 'work' from the combustion event...but a lot more heat/stress on the cylinder head.

If the fuel flow is lower than redline the mixture is leaner than ideal. As a result it is burning hotter and faster than ideal.

The combination of all of the above reduces your detonation margins on takeoff dramatically.

That is why when the new digital tach and engine monitor/fuel computer showed me I was getting less than redline RPM/fuel flow on takeoff I did something about it. The old original fit tacho/CHT/Fuel pressure instruments were simply not good enough to show the information...I was operating in ignorance of the true RPM/FF situation.

The engineer understood why I was asking for "at least redline RPM/FF...a little over is OK".

The VERY NEXT takeoff, with the engineer along, showed dramatically cooler CHTs on all cylinders which was a direct indication of wider detonation margins flowing from a combustion event happening correctly. Less heat and less stress acting on the cylinder heads, pistons, conrods, bearings, crankshaft etc.

I am not a proponent of ignoring limitations but you need to understand the what/why/when of a limitation...it is actually unfortunate that RPM/FF is presented with a radial 'redline' on the gauges at all...it should be seen as a target to achieve on takeoff not a limitation to be afraid of.

A little under RPM/FF 'redline' on takeoff is much worse than a little over. If the enginer had merely achieved exact 'redline' values I would have been happy...I am not unhappy by a little over 'redline' and it is not worth the effort and expense to chase back and forth to achieve.

Turbines are a different beast all together...exceeding redline N1/EGT etc does indeed risk the spinning fan blades contacting the surrounding shroud by exposing metals to higher than ideal temperatures at the same time as enormous centrifugal forces. The only comparable component in a piston engine is the crankshaft which is massively overbuilt and not spinning anything like as fast as the equivalent turbine componants. The forces acting on a piston crankshaft are mostly acting 'towards' the crankshaft.

By ensuring I am achieving at least 'redline' RPM/FF on takeoff I am helping to ensure engine longevity by reducing heat and stress in the cylinder heads/pistons/exhaust valves/bearings...this is one of the reasons why piston engines rarely make TBO without a top overhaul.

[Fragnasty]

More nonsense from the altar of CC:

I am not a proponent of ignoring limitations

Well actually, it would appear that you are...

As an aside I have my Bonanza set up so RPM and fuel flow slighty exceed redline on takeoff

A limit, Chuckles, is a limit. That's why they call it a limit.

[Chimbu chuckles]

More nonsense from the altar of CC:

Please prove that what I have written is 'nonsense'.

30 RPM (.01% faster) and a few liters/hr over 'redline' do not hurt a thing...the same cannot be said for the reverse situation.

How many piston engined aircraft are operating with original fit tacho and FF instruments that have not been calibrated since they were new 30 odd years ago. What RPM are they actually being turned at...what FFs are actually being achieved...how many make TBO without at least a top overhaul?

The same prop on a 210 or 185 would be adjusted to turn at 2850 RPM (.05% faster) for up to 5 minutes on takeoff.

The IO520s and 550s in Europe that are limited to 2500 RPM due to noise pollution laws have their timing adjusted so the reduced RPM on takeoff doesn't destroy the engine from detonation.

My AFM (written in 1969) has a 'limitation' that expressly forbids LOP operation but with modern engine monitors, balanced injectors and knowledge this is the best way to run and engine. Given the technology of the day that, and other, limitations were understandable and reasonable...things have changed in the last 40+ years.

Better technology has given greater understanding of what goes on inside these engines...if you don't want to benefit from that knock yourself out, but I'd really rather you came up with a more cogent argument than 'a limit is a limit'.

By your logic the further from the 'limit' the better. I can assure you that you operate too far below these 'limits' (RPM/FF with full throttle on takeoff) and you will destroy the engine in a very short period of time...in extreme examples detonation can destroy an engine in just a few seconds...and then you may well be forced into a potentially unsurvivable return to earth.

RPM and fuel flow maximums on takeoff are not 'limits' in the strict sense of that word...they are essential parameters to achieve.

Edit: And I object to the 'alter' comment too btw.

[206DOG]

Well i fly both C206 and C210's in Bots, (ground level 3000' temp between 30-45 dgrees)

I always use 20 degrees in both of the aircraft in the bush strips, reason being it does get you off the ground and into ground effect where you can safely accelerate away.

I, like ForktailedDrKiller have also used full flap on one occasion in the C210, in my case with 4 pax, 15KG bags each and 4hours fuel.
On this occasion i was about halfway down the runway, with about 50 kts on the clock when about 100 buffalo stampeded out of the nearby trees and across the runway. Popping full flap and jumping into the air above around 100 tonnes of stampeding muscle was one experience i would rather forget but it definantly saved my ar$e!

Peace

[YesTAM]

If anything, and not being a 210 driver, I've learned about looking at MP and fuel flow on takeoff - something NOT covered on my csd endorsement.

Going to try flaps 25 short/soft field technique in the Arrow before departing for Akaroola.

Thanks for this thread

[Fragnasty]

Chuckles me boy........

Deliberately exceeding manufacturers' stated limits provided for the safe operation of their equipment is bad.

Publicly admitting this, and then ranting on with a raft of reasons that justify such behaviour is even worse.

One word for you matey............. NEGLIGENCE.

[Chimbu chuckles]

RPM and FF not meeting manufacturers specs resulting in reduced detonation margins and increased wear and tear on engine.

RPM and FF adjusted to be within 1% of manufacturers recommendations resulting in cooler CHTs, improved performance and detonation margins on takeoff = negligent?

You don't seem to be able to differentiate between busting a 'limit' and modifying something in light of better information.

Clearly you know more than people like George Braly, inventor of the Gamijector, who has 1000s of hours testing and millions of data points taken from one of the most high tech piston engine test rigs on the planet.

You're the weakest link...goodbye

[Jamair]

Despite not achieving the coveted "Usual Suspects" status, I have had the pleasure of sharing technical and airmanship conversations with Gaunty and Chimbu Chuckles, as well as flying with Chuck on a number of occasions. He has in the past, and continues today to educate anyone willing to listen, from his store of hard-won experience - and is still not adverse to learning a thing or two himself.

Chucks arguments re the validity of OE gauges got me to thinking and after some research, I fitted both Gamis and a JPI to my $80,000 worth of IO-540s. I was able to replicate his experiences and after some debate with the LAME, got my fuel flows adjusted to achieve AT LEAST red-line (or to put it more correctly as per the ENGINE handbook, vs the aircraft POH, recommended maximum values - NOT absolute values. Those recommendations are STATED to be +/- 5%). These instruments / parts cost about $10,000 at the time. On at LEAST one occasion, they saved me a LEAST a $40,000 engine or worse - an in-flight emergency with paying passengers, secondary to a partial fuel injector blockage. Instantly recognisable on a JPI, never see it till you fry the cylinder on the standard clocks.

The difference was indeed eye-opening, and still leaves me with a sense of wonder at the owners and operators of essentially vintage piston engine aeroplanes who persist in using 30+ year old gauges, never calibrated and originally costing about $20 anyway, to setup and monitor the functioning of VERY expensive machinery, hauling the unknowing unwashed masses through the sky (on RPT yet!) in blissful ignorance - if only they know the age of the wonderous 'buttons and dials' tyhat so beguile the aviation innocent. The OTHER cost is what we saw demonstrated in the Spencer Gulf a few years back - would NOT have happened with decent engine monitoring equipment and educated engine operating regimes.

Fragnasty, what is your pedigree - just out of interest?

Engine rant complete.

Flaps? Limited time on C210s, but have used both 1 stage for normal / short T/O, and 2 stages for short / soft / rough (as per the POH.....). Found the aeroplane a little reluctant to perform at higher weights with 2 stages. Never had a regular situation requiring max STOL performance and not sure I would be comfortable doing that routinely. But I'm a wuss at heart and determined to be remembered for how long I lived, rather than what an Ace aeroplane driver I was.

[PPRuNe Towers]

Chimbu - Messiah or just a very naughty boy?

Chuck isn't making this all up and I know quite a few of you have already delved into the background to the 15 year movement led by a very bright US dentist, young Braly of that ilk and John Deakin. Instrumentation, initially from folks like JPI, turned that work into verifiable data.

While we tend toward the rugged indivdualist self image aviators really are pretty small c conservative and rule based. As with Lindbergh in the Pacific and the Atlantic ferry guys in WW11 it's a long haul to enlightenment - especially when the entry ticket of injectors and proper engine monitoring adds significant sticker shock given such a jaded GA fleet in Oz.

Regards to all,
Crayola Rob

PS Gaunty, does it matter if I go over the lines?

[haughtney1]

Out Rob I say OUT......and back to your North London bedsit with you

(he says from his leafy Hampshire abode)

C210 with manual flaps..and struts..lovellly

[Flintstone]

Originally Posted by PPRuNeTowers

Crayola Rob

Thought you'd been banned from crayons after you ate the last lot?

Which reminds me. Where's my bloody curry?

[Muffinman]

gaunty there's a couple of kids fighting up the back - better move them down to the front row. HH is throwing paper planes (sh%t design if you ask me) and if Flintstone eats his curry at lunch time I'm outa here, and ITCZ is still in the principals office (is this a catholic boarding school?).

By the way has FullyFlapped put away his comics and started reading the textbook?

[gaunty]

Dont' disagree with CC, Jamair or Rob at all, as long as you are prepared to spend the money on modern instrumentation, something to which, in my experience, the average GA punter is seriously allergic or in fact invokes anaphalactic shock syndrome. I have even been lectured to and hectored here at some length about trying to drive GA costs up and them out of the business.

But first you gotta get their attention and mostly they haven't got the money anyroad. Most can barely afford the aircraft in the first place so you gotta at least get em thinking about what they do or more correctly do not know, hence by allusion to one Mr Rumsfeld.
Basic correct monitoring of MAP for TO power used to be a given as part of CSU boot camp, it seems it is not now so. All the GAMI gear in the world without a thorough knowledge of and understanding of what it means, is probably going to get you into more trouble than its worth.

One thing that has not changed is the basic ABC of it.

What I'm saying is lets get the basics right first, as they seem to have become well corrupted before we even start getting fancy. CC you and the others have the experience and training to be able to take in and check off all of the readings that the GAMI stuff can give you several dozen times if you wish during the take off roll. You have to agree that if the average punter is struggling to achieve the most basic engine instrument scan during take off probably once maybe twice, more rather than less info is counterproductive.

One of the things that worries me about these sort of threads on PPRune is not the ones that "get it" it's the ones that only half do so or didn't understand the question or issue being debated in the first place. It's fairly obvious from the number of entrants in the in the annual Darwin Awards that the standard "dont try this at home folks" exhortation seems to be in fact, a challenge to actually do so.

We have moved on, and apart from recreational use the old guard piston types are as someone here pointed out "vintage", even if a "concours d'elegance" example, still vintage. Another thread talks about the delightful post war DH104 cockpit being in ergonomic terms a "dogs breakfast", fact is, almost exactly the same number and type of instruments and levers appear in the aforementioned "modern vintage" aircraft, just better arranged.

The modern ones like the Cirrus are full on single lever FADEC style which apart from making all of the above largely academic is a huge step forward.
I have always been of the view that the absolute minimum requirement for or means of intervention in an aircrafts operation by pilots has always been the best and CHEAPEST way to operate an aircraft. The airline and airline equipment manufacturers have been leading the way on this for some decades.

They like anybody who operates and/or pays the bills knows the MOST expensive thing in the cockpit is the pilot. They can, despite the desperate attempts of the operator through his ops manual and training and the most ingenious machination by the OEM, find more ways of fcuking it up was thought possible. We are now almost at the point where the options open to the pilot to do so are pretty limited or the information that they previously either guessed or had to work out is now presented in a fashion that a 5 year old child could interpret, vis a vis the Garmin 1000 stuff. And it has improved the participation rate beyond belief.

Airbus FBW has made it almost impossible to kill the aircraft or engines and Boeing aren't far behind. Cirrus have with their ballistic thingummy have made it almost impossible to get killed, The latest AW&ST has a photo of a Boeing test pilot with his hands on his head during an F18 approach, wave off and go round from a carrier, with full traps on the next test programme.

All very interesting but until the average pilot can afford anything but the most basic "vintage" aircraft lets keep it to those basics. If they want the flash stuff then they have to be prepared to pay for it, just like we did in the "good 'ol days". In the "good 'ol days" a CSU type, let alone a retractable was waaay outside the average budget so you didn't get there easily. Nowadays the costs are so unrealistically low and the "right to fly them" brigade has so distorted the market that the step from older 172 to older 210 wihout the depth of training and experience is ridiculously and IMHO dangerously short.

The real currently evolving modern aircraft has improved the participation rate beyond belief. It is like the modern motor car user friendly and without vice or the requirement for an engineering degree to operate, you can actually get on with concentrating on whats going on outside.

[gaunty]

Crayola Rob

You KNOW what happens when you go outside the line. we do not want a remake of the War of the Roses again

[YesTAM]

Airbus FBW has made it almost impossible to kill the aircraft or engines and Boeing aren't far behind. Cirrus have with their ballistic thingummy have made it almost impossible to get killed,]

Gaunty, with the greatest of respect, your pathetic faith in technology, while touching, is totally and absolutely misplaced.

There is a phenomenon that goes on in the Human race (of which Pilots, I think are a sub species, but the jury is still out on that one) called "Risk Shifting".

Now risk shifting behaviour is not yet well understood scientifically - like, but we know it occurs, because the introduction of new fangled anti-lock (ABS) brakes in cars has NOT reduced the frequency of nose to tail crashes.

What appears to be happening is that drivers have compensated for the technology by driving closer to other cars, with obvious results. In other words they have compensated so that they judge their overall risk level to remain the same.

There is apparently evidence, in what I understand to be an appalling Cirrus accident rate, that fatheaded pilots are doing the same, like the guy who headed up the East River in NYC, in marginal weather, secure in the knowledge that he could "pull the handle on the roof" if things got too tough, and hit an apartment block while trying to reverse course.

So don't be too sure that things are safer now than they were back then, because the technology - GPS, Ballistic thingummies and suchlike have made it possible for the more intellectually challenged to have a go at flying. I am living proof of this, although while I slaver every time someone tries to entice me into a Cirrus endorsement, I'm so lazy I'm put off by the sheer bulk of the POH.

As for Chimbu's treatise on engines, power levels and suchlike, I am eternally grateful because when doing my Constant Speed and Retractable, no one ever mentioned checking MAP prior to start, after start, let alone checking MP AND Fuel Flow in addition to RPM while hopefully howling down the runway. Furthermore nobody has ever picked me up on this, and I fly from a good skule, with great instructors and next month I'm flying to a short field where undetected lack of full power is going to be terminal.

[gaunty]

YesTAM

Note the liberal use of the word "almost" as in almost pilot proof.

Block or fatheaded pilots and the intelectually challenged are with us always.

It was actually I who posed the question about who knew or was ever taught how to check TO MAP. I knew and knew full well me mate CC and some others knew the answer to something that used to be taught waaay before alll this new fangled technology. I suggest you introduce the topic to your "great schule" and anybody else you know and love who fly's CSU aircraft.

As for a "pathetic" faith in technology just try and take the technology of which I speak away from the pilots (me included) in modern aircraft and see how you get on. The "pathetic" technology of which you speak actually frees the real pilot from donkey work and enables him/her to concentrate on the real game.

Risk shifting indeed changing from constant attention to minutae and donkey work to actually managing the flight.

I'll turn the ABS off next time and see what sort of response I get from my company and my passengers.
I promise you if I'm stopping in a real hurry, with all the ABS, WIPS, TRACS blah blah stuff on my motor car I am not looking forward I'm looking in the rear vision mirror coz unless the car behind has the same gear installed he is coming through the rear window. So by your lights we shouldn't have it at all.

Anyway I don't see anywhere that I have said that blind faith in it will keep you alive either.

I'm put off by the sheer bulk of the POH

hmmmm were the POH for the older types we have been talking about to have been produced in todays legal atmosphere I suspect they would be as big if not bigger, because they would have to contain all manner of arcane knowledge, previously taught as "airmanship" or part of the ground school and CASA exams perhaps.

So don't be too sure that things are safer now than they were back then, because the technology

I know they are. if only because it is just that much harder for the said block/fat head pilot to work out how to defeat it.

[Chimbu chuckles]

Gaunty while I agree that Cirrus cockpit technology is pretty impressive and have no doubt it is increasing the 'participation rate' I have some reservations that it is increasing safety levels yet...it will in time ,possibly, but I am not sure it has yet.

In my view the reason for this is the technology can lead to pilots flying in conditions they may not have attempted in in earlier technology aircraft. There has never been, and probably never will be, a technology that has no downside.

Just like the technology improvements in the 1960s coupled with the marketing hype that suggested flying was no more difficult that driving a car attracted many unsuitable people to the cockpits of Cessnas and Pipers...making something which has inherant risk easier is not always a good thing from a safety point of view just a marketing/sales one...the scuba diving industry is a classic example.

The upside of these new aircraft is that they do have imbedded in them the Gami/engine monitor technology that I firmly believe should be mandated in all piston aircraft...but are the new owners being taught how to use it? A conversation recently with a brand spanking new Cirrus owner suggests not...and he is a BA pilot not a low time PPL....he most assuredly has the capacity to take in and assimilate the information. I found myself drawing diagrams on napkins and explaining it to him...and very receptive he was too...why the information was not forthcoming from the sales people I will leave alone. He has invited me flying in his Cirrus next time we are both in UK which I am really looking forward to.

One of the aspects of increasing technology in modern airliners has been the realisation that ever cleverer aircraft don't necesarily allow dumber pilots a safe haven. The vast amounts of information available can impinge on the pilot's ability to garner what is really important at any one point in time without extensive training and experience with the technology...extensive training and experience in the new technology is what is lacking in the current "ohh ahh" reaction to this latest technology leap from Garmin.

[FullyFlapped]

Muffinman :

By the way has FullyFlapped put away his comics and started reading the textbook?

Not even had time to do any colouring in, old boy, because I've been out like a good boy practicing some of the more sensible configuration advice I've received herein (on a huge, long runway just in case ).

And the results ? Well, pretty much as advertised, really. Take off with flaps matching max aeleron deflection and 20 degrees both seem to produce the goods. Starting the take off with zero flap then dropping 20 at the appropriate point does indeed "make her shoot up like a homesick angel" - very impressive but I can imagine the effects of asymetric extension. Take off with full flaps is something I haven't tried, not really wanting to die just yet if there's no need!

Now to recreate those configs (a) at MAUW and then (b) on short grass.

Thanks for your help, gentlemen. I'm taking this 210 solo around the world next year, so if any of you fine Australian barn-storming bush-whacking beer monsters would care to meet up for a beer down Melbourne way, it'll be my pleasure to demonstrate that not all Poms drink like "Sheilas" ... even Muffinman can come out to play if we can get him a day-pass from the care home. But don't forget, if you're flying in , I'll expect to see you beating up the tower and then landing sideways across the runway before disgorging 5 20-stone miners from your 172s !

FF

[roger doger]

"barn-storming bush-whacking beer monsters"

i object......
its a shed