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Approach Climb Gradient vs EOSID

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Approach Climb Gradient vs EOSID

Old 31st Mar 2011, 17:36
  #41 (permalink)  
 
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One has to remember that the FAR and CFR, is for aircraft manufacturers for airworthiness certification.

Nothing in the CFR states, "a pilot shall" , a 'pilot' can/should/or would.

In the cert process, there are always exemptions and compliance mitigations.

It is far better to refer to PansOps or TERPS on the approach and missed parameters that are the foundation for what you use as a result, the charts.
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Old 31st Mar 2011, 19:30
  #42 (permalink)  
 
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FlightPathOBN:

One has to remember that the FAR and CFR, is for aircraft manufacturers for airworthiness certification.

Nothing in the CFR states, "a pilot shall" , a 'pilot' can/should/or would.
What about FAR 121.189?
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Old 31st Mar 2011, 20:12
  #43 (permalink)  
 
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Thanks for the laugh! I guess I deserved that, but still, nothing in the 121.189 states, "a pilot shall" , a 'pilot' can/should/or would.

These are great rules!

The 'person' can take-off as long as the aircraft can miss all the obstacles by at least 35 feet.

AND the landing and takeoff distances cannot be longer than the runway.

What else does one need?
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Old 31st Mar 2011, 20:30
  #44 (permalink)  
 
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Electronic Code of Federal Regulations:
it says "no person shall" innumerable times-in the relevant FARS on
WAT limits...


edit: really pay attention to what J_T is writing about!!!!!!!!!
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Old 31st Mar 2011, 22:11
  #45 (permalink)  
 
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it says "no person shall" innumerable times-in the relevant FARS on
WAT limits...
Of course it does -- in the operating regulations.

However FAR 25 is not an operating regulation -- rather it defines certification standards to Boeing, Embraer, Airbus, etc. Describes minimum flight paths for flight test engineers who are compiling data for AFM.

The operating rules such as 121.189 tell "persons" how the AFM data must be applied to determine maximum takeoff weight for that aircraft for the specified runway and obstacle environment. AC 120-91 provides guidance for compliance with 121.189 et al.

Isn't that what j_t and FpOBN were saying -- that there's a difference between Design standards and Operating Rules?
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Old 31st Mar 2011, 22:41
  #46 (permalink)  
 
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Good Form Zeffy!

If they had meant pilots, it would have stated 'pilots', instead, it specifically states 'persons'.

The title is 'airworthiness'...
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Old 1st Apr 2011, 00:16
  #47 (permalink)  
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Nothing in the CFR states, "a pilot shall" , a 'pilot' can/should/or would

I am having trouble believing what I have been reading if the protagonists are presumed to be competent.

Consider -

(a) compliance/certification with the Design Standards ends up in the Type Certificate and the Flight Manual. These are the documents at the top of the aeroplane food chain ..

(b) the Flight Manual gives you limitations and operating requirements which include things such as WAT limits

(c) can I ask you to explain the significance of FAR 121.173(d) which says something like

The performance data in the Airplane Flight Manual applies in determining compliance with §§121.175 through 121.197 ...

To my simple mind it follows that, if you are required to follow the operations documentation .. then you are required to follow the Flight Manual requirements ?

there's a difference between Design standards and Operating Rules?

I suggest that the philosophy is along the lines that the Design Standards start the ball rolling with a nice new shiny aeroplane. The Operational Standards then address both the implementation of the Design Standards within the operational environment and all those other things which pertain to operations but which have naught to do with Design Standards.
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Old 1st Apr 2011, 00:17
  #48 (permalink)  
 
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Hi,
I have always assumed that the approach climb gradient found from tables in the 737 manual or from LPC for A320 were single engine, as when going around at DA, we have to assume that one engine may fail and still be able to make the required gradient?
The common figures of around 3-5% would surely refer to single engine as with both engines and at normal landing weights, the climb gradient would be at least double this?
If I have completely misunderstood this and the figures refer to all engines, perhaps someone would be kind enough to explain the low figures?
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Old 1st Apr 2011, 01:04
  #49 (permalink)  
 
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fatflyer..

Within the criteria, the missed is defined using the hottest day on record for the aerodrome, at max landing weight, and lowest engine performance. That is why the low numbers. If you apply that same standard to EO, performance is significantly less.

Does the chart you are using show an EO missed track?

The criteria uses all engine for the missed approach.

from an earlier post in this thread...

"EOPs are NOT TERPS Or PANS-OPS Criteria
EOPs Do Not Provide Takeoff Data
EOPs Do Not Provide Standard ATC Departure
EOPs Are Not Developed or “Flight Checked”
EOPs Are Not Promulgated Under CFR Part 97
EOPs Are Not “Approved” By The FAA they Are “Accepted”
And… if the EOP is Associated With a “Special” IAP That Involves Unique Terrain or Pilot Flight Skills the Following Applies:"

AC120_91overview
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Old 1st Apr 2011, 01:12
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The performance data in the Airplane Flight Manual applies in determining compliance with §§121.175 through 121.197 ...

To my simple mind it follows that, if you are required to follow the operations documentation .. then you are required to follow the Flight Manual requirements ?
This means that the performance data was used to determine compliance. Its doesnt say how it was used, or other mitigations on the compliance, it just states that this particular dataset was 'applied in the determination'

The specific FM will be the compilation of all of the negotiations, mitigations, and determinations for compliance of that specific variant.
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Old 1st Apr 2011, 01:22
  #51 (permalink)  
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it just states that this particular dataset was 'applied in the determination'

I wish you well if you ever try to present that sort of nonsense to a judicial enquiry.

The specific FM will be the compilation of all of the negotiations, mitigations, and determinations for compliance of that specific variant

Indeed ... and the resulting document then constitutes the minimum Standards for the operation of that aircraft. Are you really suggesting that it is acceptable to plan and conduct operations in a manner unconservative with respect to the Approved Flight Manual ?

I take it that you have no legal competence ?
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Old 1st Apr 2011, 01:32
  #52 (permalink)  
 
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Originally Posted by FatFlyer
I have always assumed that the approach climb gradient found from tables in the 737 manual or from LPC for A320 were single engine, as when going around at DA, we have to assume that one engine may fail and still be able to make the required gradient?
The common figures of around 3-5% would surely refer to single engine as with both engines and at normal landing weights, the climb gradient would be at least double this?
Correct. Approach Climb is single-engine.

Originally Posted by JT
I wish you well if you ever try to present that sort of nonsense to a judicial enquiry.
I must admit I have had trouble following this...
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Old 1st Apr 2011, 01:51
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Indeed ... and the resulting document then constitutes the minimum Standards for the operation of that aircraft. Are you really suggesting that it is acceptable to plan and conduct operations in a manner unconservative with respect to the Approved Flight Manual ?
No...I was saying that the AFM is your guidance and nothing else.

Other:

Correct. Approach Climb is single-engine.
WRONG. Did you look at the powerpoint from the FAA?

I take it that you have no legal competence ?
Again, wrong.
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Old 1st Apr 2011, 02:07
  #54 (permalink)  
 
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OBN, if I'm "wrong", how do you explain this:

From CAO 20.7.1b:

APPROACH CLIMB PERFORMANCE
9.1 For paragraph 5.1 (b), the approach climb requirements are met if, in the
approach configuration with the critical engine inoperative at a speed not more than 1.5 VS, an aeroplane has a gross gradient of climb of at least:
(a) for a twin-engined aeroplane — 2.1%; or
(b) for a 3 engined aeroplane — 2.3% or
(c) for a 4 engined aeroplane — 2.4%.

10 LANDING CLIMB PERFORMANCE
10.1 For the purposes of subparagraph 5.1 (c), the landing climb requirements are met if, in the landing configuration an aeroplane has a gross gradient of climb of not less than 3.2% at a climbing speed not in excess of 1.3 VS with all engines operating.

Last edited by Capn Bloggs; 1st Apr 2011 at 13:19. Reason: Tone down post.
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Old 1st Apr 2011, 02:30
  #55 (permalink)  
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No...I was saying that the AFM is your guidance and nothing else

I have a reasonable background in certification and AOC stuff and I would describe that statement as "innovative". I guess that we shall just have to agree to disagree at this stage.

Takeoff ..

Heavy aircraft takeoff escape planning is based on OEI

Approach climb ..

Any time we are talking about Design Standards, approach climb means OEI, landing climb means AEO. The operations engineering folk will consider this when looking at developing landing escape procedures for nasty runways.

In the operations world, however, OEI is the operator's (pilot's) problem and one should presume that the routine runway paperwork is predicated on AEO.
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Old 1st Apr 2011, 12:42
  #56 (permalink)  
 
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FlightPathOBN:

Thanks for the laugh! I guess I deserved that, but still, nothing in the 121.189 states, "a pilot shall" , a 'pilot' can/should/or would.
121.189 a, b, c, and d all state:

No person operating a turbine engine powered airplane... (may takeoff without doing something then specified)

What are pilots, turnips?
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Old 1st Apr 2011, 15:28
  #57 (permalink)  
 
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Take the time and review the AC120 overview provided by the FAA to help clear up these types of issues.

Note page 12 EOP Criteria
Part 25 Min NET: 1.6%
AND
CFRPart 121.189.D(2):NET must clear all obstacle by 35 feet.

Note page 18, 19, 20
specifically what EOP's are NOT.

Note page 32.
KCOS Special procedures for Engine failure during takeoff or missed approach.
Note page 38
KRNO special missed approach engine out..note that on charts the EO path will be dashed. note that the EO missed track is NOT the same as the standard missed approach shown on page 37.

Note page 46
A one engine missed approach can FREQUENTLY be flown following the PUBLISHED missed approach procedure.
Doesnt this state that there is a difference? If the standard missed approach was EO, why state this?
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Old 1st Apr 2011, 22:48
  #58 (permalink)  
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Take the time and review the AC120

Keeping in mind that ACs hold no particular status other than that compliance with the recommendations should be acceptable to the FAA as constituting compliance with the related regulation.

However, one still needs to read things with an eye to linguistic logic ...
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Old 2nd Apr 2011, 14:01
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Airworthiness requirements and operating rules

From FAR Part 91:
§ 91.9 Civil aircraft flight manual, marking, and placard requirements.

(a) Except as provided in paragraph (d) of this section, no person may operate a civil aircraft without complying with the operating limitations specified in the approved Airplane or Rotorcraft Flight Manual, markings, and placards, or as otherwise prescribed by the certificating authority of the country of registry.
The approved Airplane Flight Manual, Chapter Limitations, contains the airworthiness limitations, which are the legal limits of validity of the Certificate of Airworthiness. Violation is against the law, except as provided in Part 91.

As stated in Part 91, the airworthiness limitations apply irrespective of the type of operation conducted. In addition to Part 91, there are operating regulations which apply for particular types of operations, e.g. Part 121 and Part 135.

For Large Transport Airplanes, the airworthiness limitations for performance include the takeoff and landing WAT limits, and the minimum distances required for takeoff: TOD, TOR and ASD. In addition to those, the AFM contains the performance data required for complying with the operating rules specified in Part 121 and Part 135, e.g. landing distances and engine-out flight path data for takeoff, en-route, and landing.

Regards,
HN39

Last edited by HazelNuts39; 2nd Apr 2011 at 15:48. Reason: italics
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Old 2nd Apr 2011, 14:20
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Yes -- and for Large/Transport airplanes, Part 91 goes on to state:
§ 91.605 Transport category civil airplane weight limitations.
[...]
(b) No person may operate a turbine-engine-powered transport category airplane certificated after September 30, 1958, contrary to the Airplane Flight Manual, or take off that airplane unless—

(1) The takeoff weight does not exceed the takeoff weight specified in the Airplane Flight Manual for the elevation of the airport and for the ambient temperature existing at the time of takeoff;

(2) Normal consumption of fuel and oil in flight to the airport of intended landing and to the alternate airports will leave a weight on arrival not in excess of the landing weight specified in the Airplane Flight Manual for the elevation of each of the airports involved and for the ambient temperatures expected at the time of landing;
However, compliance with the above is no guarantee that an airplane will be able to extract from an IFR approach simply by flying the (all engines) published missed approach procedure after losing an engine. That calculation is left to the operator and its provider of performance engineering/analysis.
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