Chieftain Turbocharger run down times
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Bushy
Creampuff can confirm, but it is my understanding that:
1. CASA "accept" - not "approve" - an Ops Manual; and
2. Where any contradiction exists between the POH and the Ops Manual, the POH takes precedence.
Woomera
Creampuff can confirm, but it is my understanding that:
1. CASA "accept" - not "approve" - an Ops Manual; and
2. Where any contradiction exists between the POH and the Ops Manual, the POH takes precedence.
Woomera
A Chieftain operator in Qld has brought in a requirement to check the magnetos at top of descent for dead cut at cruise power of 31MAP. While the mag switch is not switched off, the operator simply selects left then right magneto position to see if the engines runs OK. A dead mag will cause a big backfire and the theory is that delays on the ground can be anticipated and other arrangements made in plenty of time before the aircraft lands.
How completely and utterly dumb.
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Nomorecatering
Yes, do agree with your sentiments regarding cool down happening during the approach. Also agree with once you are on blocks, unless facing into wind on an ISA or colder day, the CHT's will often go up a touch.
I believe if you were able to jump out straight out after shut-down and take the cowls off to aid cooling, this could still cause problems with turbo's. The reason for the cool down is primarily to enable oil moving around the turbo to take the residual heat way. For even cooling of the turbo, the movement of oil at a low power setting does this best.
If the CHT rises a touch during this process - so be it.
Yes, do agree with your sentiments regarding cool down happening during the approach. Also agree with once you are on blocks, unless facing into wind on an ISA or colder day, the CHT's will often go up a touch.
I believe if you were able to jump out straight out after shut-down and take the cowls off to aid cooling, this could still cause problems with turbo's. The reason for the cool down is primarily to enable oil moving around the turbo to take the residual heat way. For even cooling of the turbo, the movement of oil at a low power setting does this best.
If the CHT rises a touch during this process - so be it.
Don't worry bushy, it will all become clear and simple under the new rules. They're just around the corner.
If you look at reg 215, you will see that operators are obliged to ensure that their ops manuals contain and deal with certain things, and to revise them as required. Subject to two exceptions, operators are obliged to do so unilaterally – that is, off their own bat without the approval, acceptance, endorsement, blessing or whatever, of CASA.
The exceptions are:
1. The "operational specifications" issued by CASA pursuant to subsection 4 of CAO 82.0, which must be included in a discrete section of the ops manual which cannot be changed without CASA approval; and
2. Directions issued by CASA under reg 215(3) requiring certain things to be included in, taken out of or changed in an ops manual.
However, only the important people in CASA have those powers, because their exercise is fraught with risk for CASA, as the circumstances you describe show.
CAO 82.1 subsection 2.5, CAO 82.3 subsection 2.6, CAO 82.5 subsection 3.4, and CAO 82.7 subsection 5.6 purport to be directions about the content and structure of ops manuals, but they do not have the effect of saying, for example, that "your ops manual must provide for rich of peak operations".
Despite what language might be used, CASA does not approve ops manuals. An ops manual is just one of the documents – albeit one of the most important documents – which CASA uses to reach the requisite satisfaction under section 28 of the Act. A refusal to "approve" an ops manual is actually a refusal to issue an AOC on the basis that CASA is not satisfied that operations in accordance with that ops manual would be in compliance with the rules.
If someone in CASA said they were not prepared to grant an AOC to me unless I included in my ops manual something I considered to be stupid or unsafe, I would nod and smile, change the ops manual to say what CASA wanted it to say, and then change it the second the AOC was issued. Indeed, I would consider myself to have a legal obligation to change it: reg 215(5).
If CASA then kicked up a stink, I would say: get someone important to issue me an "operational specification" under 82.0 subsection 4, or a direction under reg 215(3), and please note that if you do so, I will send a copy to my and your insurers.
As to the circumstances to which you referred, I think the FOI was very brave to do what you say he did. My prescription for him would be:
1. an AVGAS enema; and
2. intravenous Deakin articles.
If you look at reg 215, you will see that operators are obliged to ensure that their ops manuals contain and deal with certain things, and to revise them as required. Subject to two exceptions, operators are obliged to do so unilaterally – that is, off their own bat without the approval, acceptance, endorsement, blessing or whatever, of CASA.
The exceptions are:
1. The "operational specifications" issued by CASA pursuant to subsection 4 of CAO 82.0, which must be included in a discrete section of the ops manual which cannot be changed without CASA approval; and
2. Directions issued by CASA under reg 215(3) requiring certain things to be included in, taken out of or changed in an ops manual.
However, only the important people in CASA have those powers, because their exercise is fraught with risk for CASA, as the circumstances you describe show.
CAO 82.1 subsection 2.5, CAO 82.3 subsection 2.6, CAO 82.5 subsection 3.4, and CAO 82.7 subsection 5.6 purport to be directions about the content and structure of ops manuals, but they do not have the effect of saying, for example, that "your ops manual must provide for rich of peak operations".
Despite what language might be used, CASA does not approve ops manuals. An ops manual is just one of the documents – albeit one of the most important documents – which CASA uses to reach the requisite satisfaction under section 28 of the Act. A refusal to "approve" an ops manual is actually a refusal to issue an AOC on the basis that CASA is not satisfied that operations in accordance with that ops manual would be in compliance with the rules.
If someone in CASA said they were not prepared to grant an AOC to me unless I included in my ops manual something I considered to be stupid or unsafe, I would nod and smile, change the ops manual to say what CASA wanted it to say, and then change it the second the AOC was issued. Indeed, I would consider myself to have a legal obligation to change it: reg 215(5).
If CASA then kicked up a stink, I would say: get someone important to issue me an "operational specification" under 82.0 subsection 4, or a direction under reg 215(3), and please note that if you do so, I will send a copy to my and your insurers.
As to the circumstances to which you referred, I think the FOI was very brave to do what you say he did. My prescription for him would be:
1. an AVGAS enema; and
2. intravenous Deakin articles.
Grandpa Aerotart
Someone above mentioned the paucity of meaningfull engineering knowledge passed during endorsement training these days...I would have to agree.
When I did my Islander and C402 endorsements at Talair I spent 4 days going through engineering stuff with the company C&T pilot (Don Fraser)...the same as the twotter and Bandit a few years later.
When you were finished the type rating you then spent a minimum 10 hrs ICUS, real ICUS not the BS tthat is called ICUS in Oz these days, with a training pilot for the pistons and upwards of 30 in the turbines. Lots of questions asked and much good information passed by individuals with a LOT of experience on type and ****loads more in general.
Back when your employer endorsed you on complex aircraft like 402s, Chieftains etc, certainly in PNG, you were made to spend the time learning the aircraft...not so these days where individuals pay for type ratings and won't/can't afford to pay an hourly rate to listen to a ground course over 2 days. It is also very uncommon these days to find someone with real experience on type, i.e. 1000s of hrs, let alone someone who was bought through a proper training system and therefore has been taught the right way himself...more likely a full time instuctor who has a bare endorsement or at most 50 odd hrs on type logged over many years.
The days of flying 'complex' piston twins within the auspices of an 'airline' check and training system...the Talair, Hazeltons, Eastern, etc...is long passed unfortunately.
To the question at hand...if you have done a proper low drag/power approach and taxied the aeroplane properly the turbos/engines will never be cooler than at the instant you touch down...every minute of taxiing around or parked with the engines running things are getting hotter.
When I did my Islander and C402 endorsements at Talair I spent 4 days going through engineering stuff with the company C&T pilot (Don Fraser)...the same as the twotter and Bandit a few years later.
When you were finished the type rating you then spent a minimum 10 hrs ICUS, real ICUS not the BS tthat is called ICUS in Oz these days, with a training pilot for the pistons and upwards of 30 in the turbines. Lots of questions asked and much good information passed by individuals with a LOT of experience on type and ****loads more in general.
Back when your employer endorsed you on complex aircraft like 402s, Chieftains etc, certainly in PNG, you were made to spend the time learning the aircraft...not so these days where individuals pay for type ratings and won't/can't afford to pay an hourly rate to listen to a ground course over 2 days. It is also very uncommon these days to find someone with real experience on type, i.e. 1000s of hrs, let alone someone who was bought through a proper training system and therefore has been taught the right way himself...more likely a full time instuctor who has a bare endorsement or at most 50 odd hrs on type logged over many years.
The days of flying 'complex' piston twins within the auspices of an 'airline' check and training system...the Talair, Hazeltons, Eastern, etc...is long passed unfortunately.
To the question at hand...if you have done a proper low drag/power approach and taxied the aeroplane properly the turbos/engines will never be cooler than at the instant you touch down...every minute of taxiing around or parked with the engines running things are getting hotter.
Moderator
... silly me ....
I always thought that the necessaries would be in the AFM/POH and the FMS for the particular bit of kit.
Amplification I thought one might find in the OEM's operator guidance paperwork for the bit of kit ....
Guess I haven't learned much at all over the years ...
.. but I do know what I prefer to hold up in my little hand in court when the barristers are trying to hang my hide on the wall out back of the shed ....
Regulator approved certification documents and authoritative OEM words win out every time against OWTs.
A sound and thorough endorsement engineering workup is far better than two quick circuits .. and I have done both in the past .. having to catch up on the deficiencies myself in the case of the latter ..
I always thought that the necessaries would be in the AFM/POH and the FMS for the particular bit of kit.
Amplification I thought one might find in the OEM's operator guidance paperwork for the bit of kit ....
Guess I haven't learned much at all over the years ...
.. but I do know what I prefer to hold up in my little hand in court when the barristers are trying to hang my hide on the wall out back of the shed ....
Regulator approved certification documents and authoritative OEM words win out every time against OWTs.
A sound and thorough endorsement engineering workup is far better than two quick circuits .. and I have done both in the past .. having to catch up on the deficiencies myself in the case of the latter ..
Check Attitude
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Centaurus,
You have accidently hit the nail on the head with the term "run down time".
The turbocharger impellor/compressor (turbine) happily runs at around 30,000 rpm.
To do this obviously requires both lubrication, and the cooling that the bearings derive from the supply of lubrication.
The engine, while running, supplies the oil, cooled and pressurised, to do this.
If we were to shut down the engine prior to the turbine slowing down to a rate where it could survive without pressurised oil,
then the turbine could spin unlubricated at 30,000rpm, serious wear would result,
the bearings would bake any residual oil, and a seized turbine would be highly probable.
"Cooling down time" is normally accomplished by the 5 to 10 mins of approach and landing power.
However, that little turbine is stilling humming away at 30,000rpm.
So, after we reach engine idle of around 1,000rpm after touchdown, we need to wait for the little turbine to decelerate.
This normally takes about 3 minutes`to get down to about 3,000rpm turbine speed.
Then we can remove the oil supply by shutting down the engine.
The manufacturer speaks of "rundown" time, not the mythical "cool down" time.
So, what we do is start timing from when we get back to 1,000 rpm on the engine.
If we need to increase engine RPM to near or`above 1,500 rpm, we spin the little turbine up again, so we again need to start timing from when 1,000 engine rpm is stabilised.
Fortunately all of the "timed" and EGT methods produce the same result,
they ensure the turbine is spinning slow enough to handle the loss of lubrication oil that occurrs when the engine is stopped.
Large trucks often incorporate a pressurised oil accumulator to supply oil pressure for a period of time after shutdown.
So if we understand what we are really trying to accomplish,
i.e. avoiding removing the oil supply while the turbine is at high speed
and delaying removing oil pressure until the turbine has slowed to idle,
then we can understand it is smart to roll through to the end of the runway, then backtrack to the parking area.
The benefit of that is that you absorb the 3 minutes rundown time
and you can normally shut down on reaching your parking area,
and your passengers aren't sitting around wondering why you don't shut down and let them out.
You have accidently hit the nail on the head with the term "run down time".
The turbocharger impellor/compressor (turbine) happily runs at around 30,000 rpm.
To do this obviously requires both lubrication, and the cooling that the bearings derive from the supply of lubrication.
The engine, while running, supplies the oil, cooled and pressurised, to do this.
If we were to shut down the engine prior to the turbine slowing down to a rate where it could survive without pressurised oil,
then the turbine could spin unlubricated at 30,000rpm, serious wear would result,
the bearings would bake any residual oil, and a seized turbine would be highly probable.
"Cooling down time" is normally accomplished by the 5 to 10 mins of approach and landing power.
However, that little turbine is stilling humming away at 30,000rpm.
So, after we reach engine idle of around 1,000rpm after touchdown, we need to wait for the little turbine to decelerate.
This normally takes about 3 minutes`to get down to about 3,000rpm turbine speed.
Then we can remove the oil supply by shutting down the engine.
The manufacturer speaks of "rundown" time, not the mythical "cool down" time.
So, what we do is start timing from when we get back to 1,000 rpm on the engine.
If we need to increase engine RPM to near or`above 1,500 rpm, we spin the little turbine up again, so we again need to start timing from when 1,000 engine rpm is stabilised.
Fortunately all of the "timed" and EGT methods produce the same result,
they ensure the turbine is spinning slow enough to handle the loss of lubrication oil that occurrs when the engine is stopped.
Large trucks often incorporate a pressurised oil accumulator to supply oil pressure for a period of time after shutdown.
So if we understand what we are really trying to accomplish,
i.e. avoiding removing the oil supply while the turbine is at high speed
and delaying removing oil pressure until the turbine has slowed to idle,
then we can understand it is smart to roll through to the end of the runway, then backtrack to the parking area.
The benefit of that is that you absorb the 3 minutes rundown time
and you can normally shut down on reaching your parking area,
and your passengers aren't sitting around wondering why you don't shut down and let them out.
Grandpa Aerotart
John due to the unfortunate limitations of human nature, combined with the lack of technology that blighted piston engined aeroplanes until recent times, what is in the POH is NOT always the best way of doing things.
POHs are written by airframe manufacturers not engine manufacturers.
The POH for my 1970 A36 Bonanza was written over 35 years ago and recommends techniques that are gauranteed to do damage...i.e operating 25-50 degrees rich of peak egt for best economy. It suggests operating lean of peak egt is very bad for the engine, and therefore not 'approved' when there is a graph in the TCM IO 550 manual that shows data that proves exactly the opposite. Conversely TCM standard injectors make operation LOP nearly impossible and the standard fit CHT/EGT gauges are bordering on useless. One would have to assume that TCM used 'special' injectors not available as standard to get the data that their graph displays.
In the last 10 years technology, in the form of balanced injectors and all cylinder CHT/EGT monitors, has provided the information and ability to operate piston engines in a far safer and better way but human nature is such that many people are extremely resistant to accepting change. I operate my IO550 LOP most of the time and have done so now for several years since it was overhaulled and new balanced injectors/all cylinder monitor was installed...nothing indicates that the engine is not loving it and that is shown at every annual/100 hrly when the engineers peer inside with their boroscopes and check the plugs.
The approved and widely accepted techiques are very likely the primary reason cylinders rarely ever make it to engine TBO...more typically being changed around the 500-700 hr mark because compression is down or they are cracked. The reasons for this are most likley to be because they were operated at temperatures that while 'approved' were too hot and weakened the metal. I have had veteran LAMEs tell me that LOP operation causes this because the engine runs 'hotter' lean of peak egt. This is a load of ****e.
The EDM 700 engine monitor in my aircraft gives me real time EGT/CHT temperature for every cylinder accurate to 1 degree. I can see that the CHT probe on the mandated 'must be installed' triplex oil/egt/cht gauge is not attached to the hottest cylinder and that it shows fully 50 degrees F cooler than my hottest cylinder. If I didn't have the all cylinder monitor I could be happily flying along with 4 of my 6 cylinders at temperatures well over 400F and not know it. The red line is 460F. I could look down and see 440F and blissfully believe all was well when in actual fact 4 of my cylinders were well in excess of 460F. Graphs exist, and are displayed in John Deakin's writings that show temperatures much over 400F permanently weaken the metal cylinders are made of....it doesn't take much of an intellect to accept that weakened metal leads to early failure from metal fatigue..and yet Beechcraft/CASA mandated practices will lead me to that exact point.
To the crux of this thread.
When you start thinking about it logically 'cool down' periods, typically 3 minutes, make no intellectual sense. An engine is a big lump of metal that is heated up from the internal combustion process. that big lump of metal then radiates that heat into the engine cowl heating up everything that is in the cowl. That heat is removed by airflow through the cowl. Cowl flaps increase/decrease flow depending on their position open or closed. In flight at high speed ram air flow increases cooling airflow dramatically so we close the cowl flaps, opening them when speed is low to maximise flow.
Descending from cruising altitude with relatively high airpseeds and progressively reducing power settings cools the engine down gently to the point that the last 3-5 minutes of flight the power settings are very low but with still significant ram airflow through the cowl.
Having landed we slowly taxi in with the cowl flaps hopefully open...the only airflow through the cowl will be 5-7 knots from taxi speed plus a little help from prop driven airflow around the cowl and passed the cowl flaps. The prop forces no air through the cowl...take a look at the first 20-30 cm of a prop blade...it is round. We then park and sit there for 3 minutes and the ONLY airflow through the cowl, unless parked facing a significant wind, is that caused by the prop blowing around the cowl and passed the cowl flaps producing low pressure over the cowl flap and a pressure differential between the upper cowl and lower cowl...sucking air out of the cowl. The engine, even idling at 700-800 rpm is still producing significant heat from the process of combustion and there is still heat radiating from the higher power settings involved in approach....that big lump of metal takes a while to heat up and cool down....but now there is little airflow to carry that heat away...so everything starts to get hotter...and the longer you sit there blindly following a procedure that makes little sense the hotter it will get....you'd never know it looking at a standard CHT because they are not accurate enough but you can see it on my EDM 700 as the CHTs begin to march upward.
The same applies to the engine oil...virtually no airflow passing through the oil cooler so the oil temp starts rising again.
Thinking about how the turbocharger actually works will lead to some logic being applied to that system as well. At descent/approach power settings the wastegate has been wide open bypassing the turbine for an extended period of time. By the time you land the turbine will have slowed about as much as it is likely to...sitting for 3-5 minutes is just heat soaking the turbine housing.
POHs are written by airframe manufacturers not engine manufacturers.
The POH for my 1970 A36 Bonanza was written over 35 years ago and recommends techniques that are gauranteed to do damage...i.e operating 25-50 degrees rich of peak egt for best economy. It suggests operating lean of peak egt is very bad for the engine, and therefore not 'approved' when there is a graph in the TCM IO 550 manual that shows data that proves exactly the opposite. Conversely TCM standard injectors make operation LOP nearly impossible and the standard fit CHT/EGT gauges are bordering on useless. One would have to assume that TCM used 'special' injectors not available as standard to get the data that their graph displays.
In the last 10 years technology, in the form of balanced injectors and all cylinder CHT/EGT monitors, has provided the information and ability to operate piston engines in a far safer and better way but human nature is such that many people are extremely resistant to accepting change. I operate my IO550 LOP most of the time and have done so now for several years since it was overhaulled and new balanced injectors/all cylinder monitor was installed...nothing indicates that the engine is not loving it and that is shown at every annual/100 hrly when the engineers peer inside with their boroscopes and check the plugs.
The approved and widely accepted techiques are very likely the primary reason cylinders rarely ever make it to engine TBO...more typically being changed around the 500-700 hr mark because compression is down or they are cracked. The reasons for this are most likley to be because they were operated at temperatures that while 'approved' were too hot and weakened the metal. I have had veteran LAMEs tell me that LOP operation causes this because the engine runs 'hotter' lean of peak egt. This is a load of ****e.
The EDM 700 engine monitor in my aircraft gives me real time EGT/CHT temperature for every cylinder accurate to 1 degree. I can see that the CHT probe on the mandated 'must be installed' triplex oil/egt/cht gauge is not attached to the hottest cylinder and that it shows fully 50 degrees F cooler than my hottest cylinder. If I didn't have the all cylinder monitor I could be happily flying along with 4 of my 6 cylinders at temperatures well over 400F and not know it. The red line is 460F. I could look down and see 440F and blissfully believe all was well when in actual fact 4 of my cylinders were well in excess of 460F. Graphs exist, and are displayed in John Deakin's writings that show temperatures much over 400F permanently weaken the metal cylinders are made of....it doesn't take much of an intellect to accept that weakened metal leads to early failure from metal fatigue..and yet Beechcraft/CASA mandated practices will lead me to that exact point.
To the crux of this thread.
When you start thinking about it logically 'cool down' periods, typically 3 minutes, make no intellectual sense. An engine is a big lump of metal that is heated up from the internal combustion process. that big lump of metal then radiates that heat into the engine cowl heating up everything that is in the cowl. That heat is removed by airflow through the cowl. Cowl flaps increase/decrease flow depending on their position open or closed. In flight at high speed ram air flow increases cooling airflow dramatically so we close the cowl flaps, opening them when speed is low to maximise flow.
Descending from cruising altitude with relatively high airpseeds and progressively reducing power settings cools the engine down gently to the point that the last 3-5 minutes of flight the power settings are very low but with still significant ram airflow through the cowl.
Having landed we slowly taxi in with the cowl flaps hopefully open...the only airflow through the cowl will be 5-7 knots from taxi speed plus a little help from prop driven airflow around the cowl and passed the cowl flaps. The prop forces no air through the cowl...take a look at the first 20-30 cm of a prop blade...it is round. We then park and sit there for 3 minutes and the ONLY airflow through the cowl, unless parked facing a significant wind, is that caused by the prop blowing around the cowl and passed the cowl flaps producing low pressure over the cowl flap and a pressure differential between the upper cowl and lower cowl...sucking air out of the cowl. The engine, even idling at 700-800 rpm is still producing significant heat from the process of combustion and there is still heat radiating from the higher power settings involved in approach....that big lump of metal takes a while to heat up and cool down....but now there is little airflow to carry that heat away...so everything starts to get hotter...and the longer you sit there blindly following a procedure that makes little sense the hotter it will get....you'd never know it looking at a standard CHT because they are not accurate enough but you can see it on my EDM 700 as the CHTs begin to march upward.
The same applies to the engine oil...virtually no airflow passing through the oil cooler so the oil temp starts rising again.
Thinking about how the turbocharger actually works will lead to some logic being applied to that system as well. At descent/approach power settings the wastegate has been wide open bypassing the turbine for an extended period of time. By the time you land the turbine will have slowed about as much as it is likely to...sitting for 3-5 minutes is just heat soaking the turbine housing.
Last edited by Chimbu chuckles; 24th Sep 2005 at 04:33.
Moderator
Chuck,
Not suggesting that the original POH is the be-all and end-all.
However, if the owner incorporates an STC bit of kit then that STC would normally have an FMS and some OEM words to provide guidance for operating that bit of kit. The FMS then becomes the wisdom words and supersedes whatever related stuff is in the POH.
Perhaps I may have missed the point, but I was reading the earlier posts to indicate that folk were operating on the basis of Industry good guts stories rather than approved FMS data ?
If I misread it, then I shall retire gracefully from the discussion .. if not, then the consideration remains ... and one ought to consider the implications for insurance claims and so forth ...
If there is no FMS, then what is the basis for the approval of the installation of the new, whizzbang bit of kit ? .. given that the kit purports to permit the pilot to operate at variance to the information in the POH ?
Not suggesting that the original POH is the be-all and end-all.
However, if the owner incorporates an STC bit of kit then that STC would normally have an FMS and some OEM words to provide guidance for operating that bit of kit. The FMS then becomes the wisdom words and supersedes whatever related stuff is in the POH.
Perhaps I may have missed the point, but I was reading the earlier posts to indicate that folk were operating on the basis of Industry good guts stories rather than approved FMS data ?
If I misread it, then I shall retire gracefully from the discussion .. if not, then the consideration remains ... and one ought to consider the implications for insurance claims and so forth ...
If there is no FMS, then what is the basis for the approval of the installation of the new, whizzbang bit of kit ? .. given that the kit purports to permit the pilot to operate at variance to the information in the POH ?
Grandpa Aerotart
I am sure you haven't missread....this industry is awash with the 'good oil' and some of it is great...a lot is crap.
As far as STCd new stuff is concerned the case of the EDM 700, or similar, and the balanced injectors from Gami is interesting.
TCM has been absolutely against LOP operations with their engines for a very long time....but now we see the IO550 powered Cirrus operating LOP via FADEC....or some type of FADEC like technology. I guess its not the LOP that bothered them, more that someone else made it possible and they had a little ****ty about it....or perhaps pilots are not considered intelligent enough to do it without the help of a FADEC. CASA has been even slower although I have had (about 2 yrs ago) discussions with the (then?) boss of airworthiness and he reckons it's the only sensible way to run these engines...after he'd been to Ada in Oklahoma and seen Gamis Chieftain engine (TSIO 540?) running on the test stand as part of the investigation into the Spencer Gulf ATSB report
As far as STCd new stuff is concerned the case of the EDM 700, or similar, and the balanced injectors from Gami is interesting.
TCM has been absolutely against LOP operations with their engines for a very long time....but now we see the IO550 powered Cirrus operating LOP via FADEC....or some type of FADEC like technology. I guess its not the LOP that bothered them, more that someone else made it possible and they had a little ****ty about it....or perhaps pilots are not considered intelligent enough to do it without the help of a FADEC. CASA has been even slower although I have had (about 2 yrs ago) discussions with the (then?) boss of airworthiness and he reckons it's the only sensible way to run these engines...after he'd been to Ada in Oklahoma and seen Gamis Chieftain engine (TSIO 540?) running on the test stand as part of the investigation into the Spencer Gulf ATSB report
Moderator
.. and is the thrust of this thread in accord with the FMS or not ? .. not trying to stir the pot ... just unfamiliar with what might be in the FMS. I can only imagine that the answer is yes ... otherwise, one would wonder what the selling point for the kit might be ...
