CASA opinion: Aircraft must be grounded in temps over 40 degrees
I think people keep ignoring what a couple of posters have said, POH take-off charts typically provide pressure altitudes and temps however there is nothing to stop the pilot working out an equivalent density altitude and using that instead. It is just a convenience to help calculate, not a performance limitation.
If you had a density altitude that exceeded the values covered by the TO chart/table then maybe rethinking the take-off would actually be sensible. The only manual I have to hand at the moment has TO figures for a PA up to 8000' and temps up to 38C
This would mean you have a chart that covers density altitudes to over 12,000' (!)
eg
50C at Oodnadatta would have a DA I think a bit over 4000'
If you had 50C OATat Oodnadatta, although it isn't listed in the table, you pick the 4000' DA point (4000' and 7C) and you can calculate the TO distance just fine using that value. You are well within the calculated performance values even if 50C is not listed.
I seriously doubt there would be many times in Oz where a strip would ever exceed a 12,000' DA - and if there was - rethinking a takeoff in those conditions would make serious sense.
PPLs are required to understand and calculate density altitude as part of their theory course.
If you had a density altitude that exceeded the values covered by the TO chart/table then maybe rethinking the take-off would actually be sensible. The only manual I have to hand at the moment has TO figures for a PA up to 8000' and temps up to 38C
This would mean you have a chart that covers density altitudes to over 12,000' (!)
eg
50C at Oodnadatta would have a DA I think a bit over 4000'
If you had 50C OATat Oodnadatta, although it isn't listed in the table, you pick the 4000' DA point (4000' and 7C) and you can calculate the TO distance just fine using that value. You are well within the calculated performance values even if 50C is not listed.
I seriously doubt there would be many times in Oz where a strip would ever exceed a 12,000' DA - and if there was - rethinking a takeoff in those conditions would make serious sense.
PPLs are required to understand and calculate density altitude as part of their theory course.
Jonkster, there is no doubt, to me, or I suspect any trained pilot that the aircraft only cares about density altitude and that any (I've seen) p charts easily allow you calculate said density altitude.
But we are discussing the law, not aviation.
The law doesn't operate in the same way science (or mostly commonsense) does.
To a pilot, PA+OAT=DA (simplified) and therefore you and I could use the same p chart, at the same airport, in the same conditions, and come to same conclusion about rwy length/TOW. It's repeatable and falsifiable, ergo science.
To a barrister (and almost universally to a court) the p chart has temperature and pressure lines and you can't extrapolate.
If you were wealthy (hired a good team of an SC, a junior, and had good instructing solicitors) and you were lucky on the day; you might convince the court that what you say is actually correct.
But the wealth of evidence is against you. The relevant evidence acts are probably the most arcane part of our legal system, you think aviation law is turgid and dense, it's got nothing of the rules surrounding evidence and admissibility. I would suspect that you would require evidence from an expert witness (physicist, or atmospheric scientist) to testify to the formula, otherwise it is simply hearsay and would be struck. That expert is only going to have been appointed after a few directions hearing and challenges and then you better hope they impress on the day, don't say anything stupid, like it's not actually 1.98C per 1,000 feet as that's an estimate/average (bye, bye your argument).
Sounds ridiculous? Stick to flying and mooning CASA, that's what I do, it's far simpler and easier on the blood pressure.
But we are discussing the law, not aviation.
The law doesn't operate in the same way science (or mostly commonsense) does.
To a pilot, PA+OAT=DA (simplified) and therefore you and I could use the same p chart, at the same airport, in the same conditions, and come to same conclusion about rwy length/TOW. It's repeatable and falsifiable, ergo science.
To a barrister (and almost universally to a court) the p chart has temperature and pressure lines and you can't extrapolate.
If you were wealthy (hired a good team of an SC, a junior, and had good instructing solicitors) and you were lucky on the day; you might convince the court that what you say is actually correct.
But the wealth of evidence is against you. The relevant evidence acts are probably the most arcane part of our legal system, you think aviation law is turgid and dense, it's got nothing of the rules surrounding evidence and admissibility. I would suspect that you would require evidence from an expert witness (physicist, or atmospheric scientist) to testify to the formula, otherwise it is simply hearsay and would be struck. That expert is only going to have been appointed after a few directions hearing and challenges and then you better hope they impress on the day, don't say anything stupid, like it's not actually 1.98C per 1,000 feet as that's an estimate/average (bye, bye your argument).
Sounds ridiculous? Stick to flying and mooning CASA, that's what I do, it's far simpler and easier on the blood pressure.
CAO 20.7.4 is very specific that short dry grass must be used to determine takeoff distance
6.2 For aeroplanes operated on land, take-off distances are to be determined for a level short dry grass surface.
6.3 Where there is an approved foreign flight manual or a manufacturer’s data manual for an aeroplane that sets out the take-off distance required for that aeroplane, then that aeroplane must be operated so as to comply with either the requirements set out in paragraphs 6.1 and 6.2 or the requirements relating to take-off distance set out in either of those manuals.
Operate off anything else and run into the trees at the end the Feds are going to ask "how did you substantiate the take off performance? Please tender to the court the CASA approved chart".
So how does Farmer Fred go about operating his 182 to land and check his dams, bore pumps, troughs etc that CASA will accept as "legal", whatever that means? Paved, level, dry runways?
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Operate off anything else and run into the trees at the end the Feds are going to ask "how did you substantiate the take off performance?
Here it is again:
Run off the end of the runway due lack of performance and CASA will come after you. The proof is self evident. Outside the charts or not, you have demonstrably taken off overweight.
or
Get safely airborne and CASA will not come after you. Sure, somebody may dob you in because he knows you were outside the performance envelope, but even in this case, CASA would think twice about whether it would be worth pursuing you.
Well, I found that article about how to correct for the effect of short dry grass in the Sept-Oct 2002 issue of Flight Safety magazine and I was correct that the data came from the UK CAA.
The article was an analysis by “staff writers” about a takeoff accident to a Piper Lance PA-28R-300. My copy of the relevant POH has a chart to convert pressure altitude and temperature to density altitude then a takeoff distance chart presented vs density altitude only for a paved level runway. The authors focused on the importance of the correct technique per the POH and only at the end of the article did they note: “Additional factors should also be applied in the event that the performance chart does not make an allowance for variables like runway slope, runway surface, headwind component and so on (see table).” The table states a 20% increase in take-off distance for short dry grass.
Some other interesting statements in that article:
“….. It is tempting to simply say the whole episode could have been avoided if the pilot had consulted his aircraft’s take-off performance charts … However, it is unrealistic to assume that all light-aircraft pilots will calculate the exact take-off and landing distance required before every flight. ….… or the gap between the runway required and the runway available becomes marginal, the pilot refers to the performance charts and … How can we improve our decision-making skills? …….. A word of warning about aircraft performance charts. Depending on the year your aircraft was certified, its charts may or may not include built-in safety factors. ….. the production of uniquely Australian charts ceased and pilots …... calculate performance using information supplied by manufacturers. Aircraft manufacturers’ performance charts do not include built-in safety factors and in most cases reflect best-possible performance achieved with: Highly experienced test pilots …”
There was a time (two years ago) when we should’ve stopped worrying about CAO 20.7.4 – a note in the Exposure Draft of Part 91 (MOS for 91.1035 Aircraft Performance): “It is the intention that CAOs 20.7.4. …. will be subject of a project to review them and provide guidance material in the form of an AC in the future. Much of the content of the CAOs contain either certification standards or outdated information. CASA expects pilots to operate in accordance with the aircraft flight manual (AFM). All performance information in the AFM is produced and complies with the aeroplane certification standards.”
If CASA cannot prosecute a Qantas crew for taking off with no runway lighting in Hobart
Perhaps because the analysis of the FDR, and the actual activation time base showed that the lights were on at the start of the takeoff roll, and the demonstrated probability was that they went off shortly after airborne. Remember the criminal standard of proof is "beyond a reasonable doubt".
Under cross examination, "eyewitnesses" are notoriously unreliable sources of evidence, as any criminal prosecutor knows.
Back to the thread, I haven't read the whole thread, has CAR 138 rated a mention? Then you have to understand the certification base for the particular aircraft AFM/POH, to understand what is an enforceable limitation and what is advisory in an AFM/POH (if the aircraft has one).
Tootle pip!!
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Funny you should mention CAR 138, since that is what CASA cite in their letter.
Their position is that the range of the parameters in the performance charts forms part of the limitations for the aircraft.
Their position is that the range of the parameters in the performance charts forms part of the limitations for the aircraft.
andrewr,
As I said, compliance with the AFM/POH/whatever presupposes you understand which parts of the AFM/POH are mandatory, and which are advisory, in the original certification. That can only be determined by understanding the original certification basis of the aircraft. For a US certified aircraft that is reasonably easy, not so elsewhere.
Make no mistake, the AFM/POH forms an essential part of the certification documentation of an aircraft, just as much as Continuing Airworthiness requirements, Weight and Balance etc., and is listed in the Type Certificate Data Sheet or equivalent.
That is not determined by CASA, or even properly understood by many on the CASA payroll, as evidenced by the continual demands for modifications to AFM/POH mandated procedures, without having the legal power, so to do. In my opinion, invariably increasing the risk (or “less safe”, if you insist on using that particularly useless term) to the operation, usually by intolerably increasing the flightdeck workload at critical phases of flight.
Not having the power doesn’t fazed the average enforcement minded CASA employee one little bit --- “they” well understand that “you” can’t afford a High Court case to prove them wrong.**
However, major airlines can afford said HCA case, and they do understand the limitation of CASA power to “order” AFM changes. ie: nil. All airlines of my experience are very careful to go through a comprehensive and legal process, if they want to modify, in ANY way, an AFM mandated procedure. They end up with a quite legal AFM that meets their needs.
The legal and reputational consequences to airlines, of not going through that procedure are to expensive to risk.
What is done is to negotiate any desired change with the Type Certificate holder and the state that issued the Type Certificate, only with the express approval of both is any operator’s change to an AFM “legal”. What said airline has, is an amended Type Certificate.
I suppose CASA could always raise a Legislative Instrument to mandate advisory sections of an AFM, but that would be very legally dodgy, if it was to be challenged.
All the above remarks specifically relates to the Australian legislative framework, not any other country.
Tootle pip!!
** CASA will "get" you some other way, if you do not obediently fall into line ---- like refusing to issue/reissue your AOC.
As I said, compliance with the AFM/POH/whatever presupposes you understand which parts of the AFM/POH are mandatory, and which are advisory, in the original certification. That can only be determined by understanding the original certification basis of the aircraft. For a US certified aircraft that is reasonably easy, not so elsewhere.
Make no mistake, the AFM/POH forms an essential part of the certification documentation of an aircraft, just as much as Continuing Airworthiness requirements, Weight and Balance etc., and is listed in the Type Certificate Data Sheet or equivalent.
That is not determined by CASA, or even properly understood by many on the CASA payroll, as evidenced by the continual demands for modifications to AFM/POH mandated procedures, without having the legal power, so to do. In my opinion, invariably increasing the risk (or “less safe”, if you insist on using that particularly useless term) to the operation, usually by intolerably increasing the flightdeck workload at critical phases of flight.
Not having the power doesn’t fazed the average enforcement minded CASA employee one little bit --- “they” well understand that “you” can’t afford a High Court case to prove them wrong.**
However, major airlines can afford said HCA case, and they do understand the limitation of CASA power to “order” AFM changes. ie: nil. All airlines of my experience are very careful to go through a comprehensive and legal process, if they want to modify, in ANY way, an AFM mandated procedure. They end up with a quite legal AFM that meets their needs.
The legal and reputational consequences to airlines, of not going through that procedure are to expensive to risk.
What is done is to negotiate any desired change with the Type Certificate holder and the state that issued the Type Certificate, only with the express approval of both is any operator’s change to an AFM “legal”. What said airline has, is an amended Type Certificate.
I suppose CASA could always raise a Legislative Instrument to mandate advisory sections of an AFM, but that would be very legally dodgy, if it was to be challenged.
All the above remarks specifically relates to the Australian legislative framework, not any other country.
Tootle pip!!
** CASA will "get" you some other way, if you do not obediently fall into line ---- like refusing to issue/reissue your AOC.
Last edited by LeadSled; 21st Apr 2017 at 01:52.
POH take-off charts typically provide pressure altitudes and temps however there is nothing to stop the pilot working out an equivalent density altitude and using that instead. It is just a convenience to help calculate, not a performance limitation.
https://www.faa.gov/regulations_poli...t_handbook.pdf
Extract from a Cessna 207 manual - at gross, short field on a paved, dry, level runway, distance to clear 50 feet, where I've calculated the DA from the formula DA = 1.24 PA + 118.8 OAT − 1782 and extended it to 50°C.
PA/OATXXx0°CXXX10°CXXX20°CXXX30°CXXX40°CXXX50°C
0XXXXXX-1782XXX-594XXXx594XXX1782XXX2970XXX4158 DA
XXXXXXXx1770XXx1900XXx2040XXX2195XXX2355XXXXXXXfDistance
1000XXXX-542XXXX646XXx1834XXX3022XXX4210XXX5398 DA
XXXxXXXX1940XXx2085XXx2240XXX2410XXx2600XXXXXXXfDistance
2000XXXXX698XXx1886 XXx3074XXX4262XXx5450XXX6638 DA
XXXXXXXx2130XXf2295XXX2470XXX2665XXx2875XXXXXXXfDistance
3000XXXX1938XXx3126XXX4314XXX5502XXx6690XXX7878 DA
XXXXXXxX2345XXf2530XXX2730XXX2955XXx3195XXXXXXXfDistance
4000XXXx3178XXx4366XXX5554XXX6742XXx7930XXX9118 DA
XXXXxxXX2595XXx2805XXx3035XXX3290XXx3570XXXXXXXXDistance
5000XxXX4418XXX5606XXx6794XXX7982XXx9170XX10358 DA
XXXXXxxx2880XXX3125XXx3390XXX3685XXx4020XXXXXxXXDistance
6000xxXX5658XXX6846XXx8034XXX9222XX10410XX11598 DA
XXXXxxXx3215XXx3495XXx3810XXX4165XXX4575XXXXXXXDistance
7000XXxX6898XXx8086XXx9274XX10462XX11650XX12838 DA
XXXXXxXx3615XXx3945XXf4325XXx4760XXXXXXXXXXXXXfDistance
8000XxXX8138XXx9326XX10514Xx11702XX12890XX14078 DA
XXXXxxXx4095XXx4500XXx4970XXXXXXXXXXXXXXXXXXXfDistance
A Koch Chart will similarly predict adjustments, based on OAT and PA, to be made for both take off and climb data.
Their position is that the range of the parameters in the performance charts forms part of the limitations for the aircraft.
Last edited by megan; 22nd Apr 2017 at 08:21.
Folks,
Perhaps because the analysis of the FDR, and the actual activation time base showed that the lights were on at the start of the takeoff roll, and the demonstrated probability was that they went off shortly after airborne.
Perhaps because the analysis of the FDR, and the actual activation time base showed that the lights were on at the start of the takeoff roll, and the demonstrated probability was that they went off shortly after airborne.
What about this one?
https://www.atsb.gov.au/media/412877...-171_final.pdf
Here is some of the case info, I should have said Launceston but as there have been so many I confused them.
http://www.summarycrime.com/2009/05/losing-evidence-might-mean-losing-case.html
By this logic, if the performance chart for a PA28 only includes headwinds up to 15 knots then if it goes above that I can't take off or land....of course there is nothing in the "limitations" section of the POH about this
Are people really still using the little black AFMs? I thought they were legally discredited a long time ago. Though I see the text books and exams still have the "Cessna" graphs even though "real" Cessna manuals use tables.
Are people really still using the little black AFMs? I thought they were legally discredited a long time ago. Though I see the text books and exams still have the "Cessna" graphs even though "real" Cessna manuals use tables.
Moderator
headwinds up to 15 knots
Excursions which, clearly, are conservative probably aren't in question
the little black AFMs? I thought they were legally discredited
All out of vogue unless specifically approved, I suggest.
However, in general, the DCA approved P-charts were a reasonable compromise between simplicity, accuracy, and conservatism. As you would be well aware, some were a tad average ..
Excursions which, clearly, are conservative probably aren't in question
the little black AFMs? I thought they were legally discredited
All out of vogue unless specifically approved, I suggest.
However, in general, the DCA approved P-charts were a reasonable compromise between simplicity, accuracy, and conservatism. As you would be well aware, some were a tad average ..
Clare, you've got the logic arse-about. The performance chart would have to only include headwinds above 15kts for your analogy to work. More headwind is safer. More temperature is not.
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Excursions which, clearly, are conservative probably aren't in question
Or a "Normal Procedures" landing at 60-70 KIAS when the performance charts specify 61 KIAS?
Neither are on the conservative side, and there are no performance charts or tables for Normal Procedures, only Short Field. If you're not using the charts anyway, why does it matter if the temperature is outside their range?
(And if you ARE using the charts for Normal Procedures, that's worse, because you can pretty much guarantee that you won't achieve anywhere near the chart figures.)
The big boys don't fly when it's over the limits
If the runway is short and you find yourself consulting the charts, I would certainly be cautious about exceeding the temperature range. In those circumstances I might be reconsidering even if it is within the range of the charts. But a blanket statement that aircraft must be grounded seems extreme.
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Incident: Cathay Pacific B744 at Hong Kong on Jun 19th 2017, gear problem after departure
A Cathay Pacific Boeing 747-400 freighter, registration B-LIA performing freight flight CX-3290 from Hong Kong (China) to Anchorage,AK (USA), was climbing out of Hong Kong's runway 07L when the crew requested to stop the climb at 7000 feet reporting a gear problem and advised they would need to dump fuel and return to Hong Kong. The crew further advised they wanted to check whether there is any smoke from the right hand side, if not, they would start their fuel dump. The crew reported about 5 minutes later that they were now ready for a fuel dump, commenced fuel dump and returned to Hong Kong for a safe landing on runway 07L about 85 minutes after departure.
The occurrence aircraft remained on the ground for about 18 hours, then departed again and is estimated to reach Anchorage with a delay of about 19 hours.
http://avherald.com/h?article=4aa8ceee&opt=0
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Incident: British Airways B772 at Kuwait on Jun 16th 2017, engine shut down in flight
A British Airways Boeing 777-200, registration G-VIIH performing flight BA156 from Kuwait (Kuwait) to London Heathrow,EN (UK), was climbing out of Kuwait when the crew stopped the climb at FL160 reporting an engine (GE90) failure. The crew shut the engine down and returned to Kuwait for a safe landing on runway 33R about 45 minutes after departure.
Passengers reported the captain announced they had needed to shut one engine down.
The occurrence aircraft is still on the ground in Kuwait about 87 hours after landing back.
http://avherald.com/h?article=4aa8ccc1&opt=0
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Incident: Atlasjet B738 at Istanbul on Jun 18th 2017, lightning strike
An Atlasjet Boeing 737-800, registration TC-SNT performing flight KK-9764 from Istanbul (Turkey) to Tbilisi (Georgia), was climbing out of Istanbul when the crew stopped the climb at FL180 following a lightning strike and decided to return to Istanbul for a safe landing on runway 35L about 50 minutes after departure.
The occurrence aircraft received damage and remained on the ground for 10.5 hours before returning to service.
http://avherald.com/h?article=4aa8cabf&opt=0
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Phoenix flights cancelled because it's too hot for planes
A plane is silhouetted against the sky as it takes off from Heathrow Airport 19 December 2002 in London, England.
Even for Arizona, the temperatures are high - hot enough to stop flights
As temperatures climb in Phoenix, Arizona, more than 40 flights have been cancelled - because it is too hot for the planes to fly.
The weather forecast for the US city suggests temperatures could reach 120F (49C) on Tuesday.
That is higher than the operating temperature of some planes.
American Airlines announced it was cancelling dozens of flights scheduled to take off from Sky Harbor airport during the hottest part of the day.
The local Fox News affiliate in Phoenix said the cancellations mostly affected regional flights on the smaller Bombardier CRJ airliners, which have a maximum operating temperature of about 118F (48C).
The all-time record for temperatures in Phoenix is just slightly higher, at 122F, which hit on 26 June 1990.
The cancelled flights were scheduled to take off between 15:00 and 18:00 local time.
Why can't planes fly?
At higher temperatures, air has a lower density - it is thinner. That lower air density reduces how much lift is generated on an aircraft's wings - a core principle in aeronautics.
That, in turn, means the aircraft's engines need to generate more thrust to get airborne.
It's a well-known problem - a 2016 report from the International Civil Aviation Organization (ICAO) even warned that higher temperatures caused by climate change could "have severe consequences for aircraft take-off performance, where high altitudes or short runways limit the payload or even the fuel-carrying capacity".
Those problems are why many countries in the Middle East, and some high-altitude airports in South America, tend to schedule long flights for the evening or night, when it is cooler.
Bigger aircraft like Boeing 747s and Airbus models have a slightly higher operating temperature, and have not been affected by the heat in Phoenix.
An American Airlines statement provided to The Arizona Republic newspaper said those jets should be fine up to 126-127F (53C) - just a little higher than what is expected.
Those temperatures, however, are forecast for the aptly named Furnace Creek in Death Valley, in California, with some areas expecting new temperature records on Tuesday.
The Death Valley National Parks Service has issued a warning to visitors to avoid hiking after 10am, and to "travel prepared to survive".
http://www.bbc.com/news/world-us-canada-40339730
Where do CASA's declared density altitude charts fit into all this, they don't mention temperature
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A very good question!
Declared density is a substitute for knowing the temperature. You can use a standard temperature and higher altitude in your charts - exactly what this opinion says you are not allowed to do.
So maybe you are not allowed to use declared density any more, or maybe CASA didn't think things through when they wrote the opinion.
Declared density is a substitute for knowing the temperature. You can use a standard temperature and higher altitude in your charts - exactly what this opinion says you are not allowed to do.
So maybe you are not allowed to use declared density any more, or maybe CASA didn't think things through when they wrote the opinion.
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7.4 AFM – High ambient temperature operations
Background: The Convenor received the following information of interest. The attached CASA response confirms this is not a CASA/RAPAC responsibility – rather manufacturers – but RAPAC members should take note:
“Many areas of Australia have encountered above 40 degree C temperatures in recent times, and will likely encounter them again in subsequent years. The attached map from the BoM website chronicles the period 1 November to 31 January.
CASA was asked: if an aircraft's AFM caps performance data at 40C, can the aircraft still legally fly when the ambient is above 40C? Of note: "unless a declared emergency situation exists, if ambient conditions exceed the limitations set out in the AFM, including the range for which performance data is provided, the aircraft must be grounded". This is a significant announcement and has widespread implications. Insurance companies rely on a pilot's compliance with CASA's rules and regulations when considering if a claim is to be processed.”
Discussion: The Convenor indicated that the item had been included for the information of members and to raise awareness of the issue.
Mr Walker confirmed CASA’s position that aircraft needed to be operated within the parameters published in an aircraft flight manual and there was no provision to extrapolate performance data beyond that provided.
Background: The Convenor received the following information of interest. The attached CASA response confirms this is not a CASA/RAPAC responsibility – rather manufacturers – but RAPAC members should take note:
“Many areas of Australia have encountered above 40 degree C temperatures in recent times, and will likely encounter them again in subsequent years. The attached map from the BoM website chronicles the period 1 November to 31 January.
CASA was asked: if an aircraft's AFM caps performance data at 40C, can the aircraft still legally fly when the ambient is above 40C? Of note: "unless a declared emergency situation exists, if ambient conditions exceed the limitations set out in the AFM, including the range for which performance data is provided, the aircraft must be grounded". This is a significant announcement and has widespread implications. Insurance companies rely on a pilot's compliance with CASA's rules and regulations when considering if a claim is to be processed.”
Discussion: The Convenor indicated that the item had been included for the information of members and to raise awareness of the issue.
Mr Walker confirmed CASA’s position that aircraft needed to be operated within the parameters published in an aircraft flight manual and there was no provision to extrapolate performance data beyond that provided.
if an aircraft's AFM caps performance data at 40C, can the aircraft still legally fly when the ambient is above 40C?
Of note: "unless a declared emergency situation exists, if ambient conditions exceed the limitations set out in the AFM, including the range for which performance data is provided, the aircraft must be grounded".
Of note: "unless a declared emergency situation exists, if ambient conditions exceed the limitations set out in the AFM, including the range for which performance data is provided, the aircraft must be grounded".
Where do CASA's declared density altitude charts fit into all this, they don't mention temperature
What if you cannot determine your weight !?!?! (okay I added the !?!?!)
In reality, if you are a driver and cannot figure out your MTOW, then it does not matter what the temperature is, you should be restricted from taking off.
if an aircraft's AFM caps performance data at 40C
including the range for which performance data is provided,
The MTOW and associated parameters with ISA with airport altitude and temperature are well defined.
ISA and ISA d....is there an understanding of the ISA temp/altitude, (and MTOW) and what one must do when NOT within those parameters???
With the ISA D, you can determine what MTOW is based on per the temperature D. If the temp is higher than listed, you need to weight limit, and calc the new MTOW.
When ac look at restricting ops with temp, it means that IT cannot meet DEP obstacle clearance EO, and UNLESS you have an EO approved procedure, thus must follow the SID procedure.
In reality, I have significant concerns with drivers who have no understanding of MTOW, associated temperature limitations with the associated effects, nor the comprehension of the necessity to calculate take off weights for their aircraft..
Last edited by underfire; 21st Jun 2017 at 09:14.