172 Take off and Landing Charts

[Rochbain]

Hi guys,

Im currently a lowly GFPT student , and im chasing Takeoff and Landing Charts for the C172 N Model, However Google only links me the POH for the aircraft which has everything but.

Ive done a PPRuNe forum search and have come up to no avail.

If anyone knows of somewhere online to access one it would be greatly appreciated :confused:


Regards
Kev.

[Ozzie Mozzie]

If you have the full POH they'll be in there. The PDF I have which I used for training has them on page 42/73, in section 5.

They are more just tables then charts, but you can interpolate between the figures. Remember to add all your extras (15% for CASA).

[Rochbain]

Ahh apologies Ozzy, Not those charts, but now to be more specific they are called "Take off Weight Charts/Landing Weight Charts" and they were published by the Department of Civil Aviation and look quite ancient,

Consisting off T/O distances, AF Pressure Heights, Slopes, H/T Winds, etc

[Lasiorhinus]

Your instructor will be able to supply these for you.

[Aussie Bob]

Remember to add all your extras (15% for CASA).

Why would you do that?

[MakeItHappenCaptain]

6 TAKE-OFF DISTANCE REQUIRED

6.1 Subject to paragraph 6.3, the take-off distance required is the distance to accelerate from a standing start with all engines operating and to achieve take- off safety speed at a height of 50 feet above the take-off surface, multiplied by the following factors:
(a) 1.15 for aeroplanes with maximum take-off weights of 2 000 kg or less;
(b) 1.25 for aeroplanes with maximum take-off weights of 3 500 kg or
greater; or
(c) for aeroplanes with maximum take-off weights between 2 000 kg and
3 500 kg, a factor derived by linear interpolation between 1.15 and 1.25 according to the maximum take-off weight of the aeroplane.

6.2 For aeroplanes operated on land, take-off distances are to be determined for a level short dry grass surface. For aeroplanes operated on water, take-off distances are to be determined taking into account the maximum crosswind component and the most adverse water conditions for the aeroplane type.

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.

Note: The data contained in some manufacturers’ data manuals is unfactored and makes no allowance for degraded aircraft performance. Where there is a considerable difference between the data in a manufacturer’s data manual and the data in the flight manual for the aeroplane then the manufacturer’s data should be treated with caution.

The factors had to be used when the old A5, typewritten, didn't tell you jack CASA flight manuals were the approved flight manual.

[Aussie Bob]

Also 1:15 is not 15% according to my calculator
Thank goodness common sense prevailed and we got rid of that ****e ...

[john_tullamarine]

Folk need to be wary of foreign POH data. Generally we are operating from non-critical lengths and it is very easy to fall into the trap of convincing yourself that it is all fine and OK.

Reality is that, for a critically limiting takeoff .. it just might NOT be all OK.

The old style DCA flight manual P charts (a few of which I drew up) were a reasonable balance of being not too optimistic and not too conservative.

You use the foreign POH with uncritical consideration at your peril in the case of critical distance takeoff.

Also 1:15 is not 15% according to my calculator

Allowing for the typo, if 1.15 isn't a 15% pad, what is it ?

[LeadSled]

but now to be more specific they are called "Take off Weight Charts/Landing Weight Charts" and they were published by the Department of Civil Aviation and look quite ancient,

Rochbain,
These charts have had no legal standing since 1998, and cannot be (legally) used for current operations.

Somebody will correct me if I am wrong, but my memory says that you do not now have to (legally) apply factors for Private Operations, only operations that come under CAR 206.

That doesn't stop you being conservative ( a good way to stay alive) and adding a good pad to the un-factored figures.

Just why do you want the old DCA Charts --- except as hysterical (sorry, historical) interest. I do hope nobody is misleading you as to present requirements.

John T, I have often wondered about some of the DCA charts from the "little black books". back in the late '90's we did some sampling, and the DCA charts for some aircraft produced lower takeoff and landing distances than the un-factored manufacturer figures.

As a matter of interest, some of the more recently FAA certified small jets have performance figures presented as per FAR 25, even though the aircraft is only FAR 23.

Tootle pip!!

[tail wheel]

back in the late '90's we did some sampling, and the DCA charts for some aircraft produced lower takeoff and landing distances than the un-factored manufacturer figures.

And according to DCA, some aircraft - e.g. the Skrike 500 - could and still legally carry a pay load in Australia that would be criminal in any other country!

[john_tullamarine]

These charts have had no legal standing since 1998, and cannot be (legally) used for current operations.

not quite. Nothing to stop one getting approval to use them.


you do not now have to (legally) apply factors for Private Operations

as I recall, just as the rules changed back then a well-known light jet came to grief when the landing chose not to consider those same factors .. much to the amusement of many in the Regulator who saw the folly of indiscriminately throwing out the baby with the bathwater ..

That is to say, legal may not equal sensible in all cases ...


That doesn't stop you being conservative

we rest our collective case


Just why do you want the old DCA Charts

not suggesting that the old P charts were the be all and end all. But they were rational, sensible and, in the main, useful


the DCA charts for some aircraft produced lower takeoff and landing distances than the un-factored manufacturer figures.

that might well be the case although I can't bring any specific examples to mind. There was a bit of variation in technique depending on who did the work. Beyond that, it would need a looksee at the specific charts you have in mind. Another strange one was that subset of the landing charts where el-cheapo flight test work was done to determine a starting point for gross weight only and then the data was expanded for a constant landing speed ie independent of weight.


some aircraft - e.g. the Skrike 500 - could and still legally carry a pay load in Australia that would be criminal in any other country

simple story with this one.

the US requirements for OEI climb were tied up with the stall speed. The Oz requirement was a simple gradient.

By comparison to heavier models, the Shrike was able to take advantage of a bit of structural over design. The local gross weight limit then became demonstrated OEI-climb-limited and the aircraft picked up a significant increase in MTOW and, hence, payload.

The Shrike has to be my favourite light twin ..

We did something similar for the 500A, using a parts list comparison to the Shrike if my memory serves me correctly.

[aussie027]

So, what is the requirement today then re Tkof and landing distances????
According to what makeithappencapt posted it says u have to factor the figures in 6.1 but in 6.3 it says follow the above paras,6.1 and 6.2 OR not if you have approved foreign manuals, you can use the figures in those manuals.

So legally if you have manufacturer's manuals you can use those unfactored???

[Aussie Bob]

If 1.15isn't a 15% pad what is it

Good point John and I apologise, must of been having a blonde moment ...:oh:

[LeadSled]

Aussie027,

Depends on what kind of operation you are conducting, and what type of aircraft.

John T,
I have to disagree with you, CASA has no legal power to approve a set of performance charts that vary from the AFM. See Part 21, CAR 138, amongst others -- our regulations are so simple and straight forward.

What they can do is impose a factor on the AFM figures, by way of a direction or by not "accepting" an operations manual for an AOC operation, unless the factors are imposed as part of the manual.
To a degree, this will be "clarified" in Part 135, which is a very restrictive document for any "passenger transport" (nee Charter) operation, compared to what we have been used to
.
Of very serious concern in Part 135 is the aerodrome standard, carrying a bunch of cattle buyers into the farm strip will be history, likewise use of about half the strips on ERSA, or a much higher proportion of strips in the AOPA Aerodrome Guide, which has about double the number of ERSA.

Tootle pip!!

[john_tullamarine]

So legally if you have manufacturer's manuals you can use those unfactored???

Legally relates to what the judge says.

Pragmatically, one needs to be aware that the US rules, in particular, have two parts - the airworthiness design standard and the operating side, the two to be read in conjunction.

I suggest that it is a little risky to read the one (via the POH) without being cognisant of the other ...

Once CASA eventually gets around to finishing the forever project to rewrite the Regs it might all get tidied up, I guess ?


must of been having a blonde moment

Not sure what I'm having when I have those myself .. certainly not enough hair for it to be a blonde moment ... pass, bro


CASA has no legal power to approve a set of performance charts that vary from the AFM

That may be the case these days .. I've been out of the light civil scene in Oz for some years. However, djpil should be able to offer a current engineering comment so I've flicked him the question for interest.

[jas24zzk]

Once CASA eventually gets around to finishing the forever project to rewrite the Regs it might all get tidied up, I guess ?

I don't see it, as it is more and more questions that had easy and qualifiable answers (in re the regs) just seem to be getting muddier and muddier.


In court you will be grilled about some obscure reg you broke whilst simply trying to fly the plane, but the regulator is permitted to give you hidden/obscure/undecipheral rules on IMPORTANT information that you require for the simplest of operations. I call a CROCK!!!!!

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Leadsled said..
Somebody will correct me if I am wrong, but my memory says that you do not now have to (legally) apply factors for Private Operations, only operations that come under CAR 206.

Whilst I can understand some operations having regs that require them to carry some extra fuel/equip etc, I cannot fathom why Private Ops would need lower TDR/LDR requirements than any other operation. After-all the aeroplane doesn't know what operation you are conducting, it only cares about its environment.

Use of 'rules' of thumb requires you to remember something operationally important, that is better presented in a written format, just like checklists.

Yes I prefer the older charts.

[LeadSled]

I cannot fathom why Private Ops would need lower TDR/LDR requirements than any other operation.jas24zzk,
Because the law allows it. Ultimately, it is up to the PIC to ensure the aircraft performance is adequate for whatever operations you are conducting.

The factored figures will not provide adequate protection in many circumstances, just as operating on the limits of "Limitations" in the AFM might not provide adequate. protection.

Know your aeroplane thoroughly, for many (most??) a pilot, it will be impossible to even achieve the factored filed lengths in day to day operations, let alone the unfactored numbers, or the numbers on the old and no no longer legal DCA Flight Manuals.

This is particularly so with landing field lengths. Think about it, do you know how the base figures were established? Can you fly that well?? For most light GA operations I witness, the demonstrated day to day landing field length is probably double the "book" figure, starting with approach speeds that are far too fast. Can you still achieve the "book" figures with the limiting or maximum demonstrated crosswind.

Largely, ½ MV2 does the rest.

Tootle pip!!

[john_tullamarine]

Discussed the old charts with djpil. Like me, he is a bit removed from the cut and thrust these days .. but thought that LeadSled's view was correct. For my own interest I'll touch base with some CASA buddies when convenient and check out the current story from the horse's mouth.

it will be impossible to even achieve the factored filed lengths in day to day operations

takeoff shouldn't be too much of a problem but landing is a whole different ball game.

Think about it, do you know how the base figures were established?

Generally, you won't have any way of knowing the detailed history. However, the AFM should give you a story, especially for the heavies.

As an overview, though ..

(a) the base data will be determined from the standard mathematical modelling for takeoff and landing with flight test confirmation of particular test card points to derive fudge factors to make the theory better fit the reality.

(b) OEM flight test will be flown as critically as the OEM can get away with .. you only really have the Regulator's oversight to safeguard against things getting a bit too optimistic.

Having said that, TPs of integrity will be doing a pretty good job. However, it would be foolish to think that the TP has much interest in addressing the typical sort of flying one might see at the aero club or on the line. Performance take off and landing trials set out to get "good" data for the OEM's marketing effort.

The military TP programs probably are a bit more interested both in the optimum data as well as addressing line problems and concerns.

In the case of, say, the old DCA charts, several techniques were represented ..

(i) the more serious work would involve an experienced experimental TP with cinetheodolite recording for read out of test data.

(ii) as we moved down the dollar scale, one used simple still camera records to figure the 50ft point and liftoff/touch down points. Very crude but, nonetheless pretty effective. The pilot could be a TP or even a moderately experienced CPL type of chap/chapess.

(iii) sometimes, Industry would talk DCA into permitting the use of test points from FAA approved POH data and then the expansion would follow the usual DCA techniques.

In the good old days, expansion of test points would have been via slide rule, later machines such as the HP calculators ... and finally microprocessor devices/PCs. The equations used were fairly basic derivations from kinematics although as we moved into the larger OEMs, the resources permitted very elegant modelling to get the data to agree with FT as close as could reasonably be achieved. The number crunching devices became much bigger and faster as well.

One of the problems between the FT/aerodynamicist work and the aero club real world is that the former were out to get the best data they could. In addition, the TP would discard runs he/she didn't like. Then, during analysis, the aerodynamicists would discard a few more of the poorer quality runs. End result was that the data presented to the certificating Regulator was skewed to the good side.

I suggest that, in general, any pilot without an FT background who talks him/herself into believing he/she can replicate unfactored AFM data .. especially for landing .. is just having him/herself on. A fool's errand. The TP is going to be doing well to replicate the published unfactored data !!

Landing technique generally is along the lines of

(a) steady approach angle

(b) weather conditions perfect and nil wind

(c) approach speed as scheduled plus/minus nil

(d) 50ft is not critical as the data capture and analysis shifts the exercise to suit .. ie the test work is done on long runways where it doesn't matter an iota where the actual touch down point is. The only real constraint is that it be within a reasonable range for the data capture setup

(e) throttle closure generally will be at 50ft

(f) the flare generally will be somewhat more aggressive than that used by Joe Bloggs, aero club pilot

(g) maximum braking means just that .. until the aircraft has really stopped.

[jas24zzk]

I cannot fathom why Private Ops would need lower TDR/LDR requirements than any other operation.
jas24zzk,
Because the law allows it. Ultimately, it is up to the PIC to ensure the aircraft performance is adequate for whatever operations you are conducting.

I already got it in the framework you responded with. I still cannot understand why (and I know it does) the law permits the use of different parameters for TDR/LDR requirements between operation types.

EG, does it allow different MTOW requirements between pvt/chtr/rpt for the same type? (forgetting exemptions/stc's etc) I haven't read anything that suggests this, but have certainly read some of the waffle that affects performance charts.

It strikes me, that CASA in allowing/permitting use of the old DCA charts found itself legally liable if the data was incorrect. They re-wrote the regs for us to use the rules of thumb etc.
They put the onus on us to decipher the OEM's charts, apply almost unsubstantiated rules of thumb, and re-wrote the regs to ensure that if we get it wrong, we cop it, not them.

I just don't see the removal of the DCA charts as being productive. Reading John's post, I see faults in the DCA system, however I do not see any reason why the DCA system charts could not be continually developed and amended. Afterall it would be in the interest of SAFETY.

After doing some reading, chatting to a few jet jockey friends and due consideration, it is very clear the difference between our lil 172 that started this thread and the big boys is the quality of the OEM data.

For every 172 that crashes due crap(hard to implement data) they will sell 50. If say an A320 crashes due bad TDR/LDR data the company will be pumelled by 500 end users, and lord knows how many regulatory bodies.

The regulatory situation at the lighter end of our industry as I read is farcical, and an accident awaiting to happen...is that what it will take? :{

CASA have muddied the waters, certainly at the lower end of the scale, for those least able to afford to defend themselves. This and other threads just align with regulation rather than dissemination of practical information.

Cheers
Jas

[john_tullamarine]

For whatever my view may be worth, I see no problem using an old P chart (generally with which I am comfortable) provided that I also check that I am not unconservative with whatever prescribed data is the flavour of the month.

That is to say, I see no problem using the old P charts to add a sensible level of conservatism to the light aircraft POH data.

CASA and the judge will only be interested if you were to operate non-conservatively with respect to whatever the requirement may be .. it is up to you as to how much, and by whatever technique you might use, conservative fat you add for mum and the kids.

I suggest that the regulatory harmonisation process was not about CASA's liability at all but a consequence of studies which concluded that the benefits to be had by removing local differences were a valuable goal.

Whether one might agree or not is the province of one's own assessment.

[jas24zzk]

I suggest that the regulatory harmonisation process was not about CASA's liability at all but a consequence of studies which concluded that the benefits to be had by removing local differences were a valuable goal.

I have no problem with that. Until I start looking at the local differences and valuable goal.

1. Local differences.
Who is affected? Theoretically us. If you train under that system, then it makes not one iota of difference to you, as it is what you have always known. For a foreign pilot, if they want to convert their licences, then they would have to learn it, same as we would have to learn stuff if we moved to their country.

2. Valuable Goal.
You probably hit the nail on the head there. CASA just wiped out half a dozen jobs and a whole department. probably saved em 400-600k per year.

--------------------------------------------------------------------

Of interest, the old DCA charts are still the ones you teach for PPL and CPL (A)

I seriously think CASA have lost the plot on this item of imperative operational info.

[john_tullamarine]

It's going back a while now but my recollection is that Ron Yates' report in the 80s was the catalyst for the whole exercise.

Piloting was only a small part of the exercise, I suggest.

As to savings, that may well have been a consideration ...

[LeadSled]

jaz24zzk,
I am amazed at the statement in one post by somebody, that CASA still uses the old DCA charts in the training syllabus.
As to "safety" matters, the US has a darned sight better safety record than we have, why are using out of date and no longer legal charts going to improve "safety".

If there is an incident or accident, CASA takes a very dim view of using unapproved data --- even having it in the aircraft is taken as proof enough, as several pilots/owners have found out the hard way since 1998.

Several reasons why you can't use them operationally:

1) The legislation which authorized them has long since been repealed. They are legally uncertified data.
2) The AFM, part of the basic type certification of the aircraft (and not an "Australian" manual produced as part of an Australia certification to unique Australian rules) is the document you are obliged by law to use, see Part 21 and CAR 138.

Under CASA's power to issue a direction, they can enforce the "factors".

Why does CASA "allow" differences for PVT versus the others? Simply because, clear across the regulatory structure, we apply more stringent standards, the greater the consequences of something coming unstuck.

If it were to be one size fits all, why not the same pilot license for all, after all, one way and another, pilots are at the heart of a very large proportion of accidents ---- A minimum of an ATPL for all would be the way to go for PVT operations, wouldn't it.

As a general rule of thumb, if I haven't got at least double the figure I get out of the AFM available, I give the intended operation very careful consideration. And I did have UK ARB flight test (not experimental test) approval for aircraft <12,500lb, back in the good old days.

John T,
Have you ever had a close look at the old UK ARB/BCAR test standards, versus the various iterations of the FAA Flight Test Guides and various amendment levels of , say, FAR 25.

In short, the poms allowed for a considerable spread of pilot ability, but then only applies small factors. The FAA approach, staring of with TP standards of flying, then applied big factors (eg: landing 60/40) ----- in the end the actual performance figures were much the same, except for the poms approach to Vmcg limited V1's in a cross wind, and it effect on balanced field lengths. As a result, a BA 747 essentially can't use 27 at YMML at light weights with any crosswind, even with a howling south/westerly, they have to accept the x-wind on 16.

Tootle pip!!

PS: I am reminded of the number of aircraft DCA seriously damaged or wrote of conducting "certification flight tests" to the old rules. Remember the Riviera still on the bottom of Pittwater , the Merlin at Mangalore, several Aero Commanders, etc.

[Ozzie Mozzie]

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