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Approach Climb Gradient vs EOSID
at our company we are required to fly the EOSID in case SE missed approach at certain airports and OAT.
in the regulatory sense, can we plan to fly an approach above max approach climb limiting weight if instead of the published GA we plan for EOSID ? thank you! |
Yes you can. Just check you are not over MTOW for that runway for given conditions.
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I don't think so.
Approach climb gradients are mandatory, I think. The airplane should be able to carry out the missed approach procedure and clear all obstacles with one engine out, if it is initiated at or above DA or MDA. |
Microburst 2002
I think that answer is rather too simplistic. Take an example where you have just departed an airport at maximum TOM and suffer and engine failure/fire, say one that won't extinguish. You decide that you want to return immediately to the same runway at the current weight/mass.
A quick check (or even better a slow one before departure) shows that yes, you can stop on that runway but in the event of a missed approach you cannot meet the E/O gradient. Its now up to you. You may be able to come up with an alternative missed approach procedure which MAY or may not be the same as the EOSID you had just used 10 minutes ago. The primary goal being to conduct a MAP safely avoiding all terrain and of course you must get ATC approval before commencing the approach (maybe too late if you call for it during the miss). A word of caution though: MD83FO I really hope your company has checked that such EOSIDs are appropriate for the airfileds at which they wish you to use this procedure. An EOSID has nothing to do with a missed approach whatsoever as they are both flown from geographically different locations e.g. 2 nm or more difference. However it may be the case at certain airfileds it will be perfectly possible to safely follow the EOSID during a miss, whilst at others it may well not. |
app climb gradient
Actually, i have the same question.
An approach with 2 different DA depending on your approch climb gradient. So you punch in the figures in the computer and it tells you cannot make the climb gradient for the lower DA. By using the higher DA, what happens if the engine fail after you passed that (higher) DA?:confused: I can't remeber which airfield it is now...i know i've seen the charts before....:O |
what happens if the engine fail after you passed that (higher) DA?
It's called risk assessment and management and, to the maximum extent practicable, should be done by the operator's flight standards and ops eng people in the comfort of their offices and well ahead of the event ... (a) identify and assess the risk. This may be able to be done quantitatively or, in many cases, only qualitatively (b) determine what options may be available to mitigate the risk (c) what mitigation is practical, put in place (d) if the risk cannot be mitigated to the level desired, either don't do the operation or escalate the decision to accept/reject the risk to an appropriate level Depending on the operation, there may/may not be regulatory requirements in respect of acceptable risk. Main thing is not to blunder blindly into the situation of risk and then wonder what might be a good way of surviving ... that's just a good way of killing yourself. |
Originally Posted by MD83FO
in the regulatory sense, can we plan to fly an approach above max approach climb limiting weight if instead of the published GA we plan for EOSID ?
Originally Posted by Starbear
Take an example where you have just departed an airport at maximum TOM and suffer and engine failure/fire, say one that won't extinguish. You decide that you want to return immediately to the same runway at the current weight/mass.
If I was on fire there is absolutely no way I'd be not conducting an immediate return to land simply because I was over the normal Landing Climb or Approach Climb limit weight. The other option, going somewhere else/burning off fuel, is obviously not going to work. To keep the G/A option up your sleeve, you could keep the speed up (until committed to land) to aid climbing, as well as land at a lower flap setting. |
An approach with 2 different DA depending on your approch climb gradient. So you punch in the figures in the computer and it tells you cannot make the climb gradient for the lower DA. By using the higher DA, what happens if the engine fail after you passed that (higher) DA? Best RGDS |
IMHO I don't feel that your company needs follow their current procedure unless you are flying a Cessna 402. An MD80 will easily comply with the gradient from DH on SE.
Cheers, D.L. |
An MD80 will easily comply with the gradient from DH on SE. |
The airplane should be able to carry out the missed approach procedure and clear all obstacles with one engine out, if it is initiated at or above DA or MDA. 2.5% is all engine...make no mistake about that. One has to remember that the Missed and EO consider the hottest day of the year for that aerodrome. Many EO procedures in AUS use 60'/nm as climb gradients. http://fsims.faa.gov/wdocs/Orders/82...s/image254.jpg If you call up the different procedures in the box, you will likely see completely different routes for EO procedures.(RNP) EOSID can help you decide if you want to land at that aerodrome if you are on EO approach, or go to an alternate. Engine out procedures are not in any design criteria. You must submit them to show what would be your route, but you will never get anything but a thank you. One reason you may see different DA's can be because of extreme cold temps. There will be a DA for temps down to -20C, then another DA for temp below -20C on baro... |
Some operators do this:
go around above DA: follow missed approach procedure go around below in IMC: follow EOSID but I never saw anyone briefing for the latter possibility |
For a go around below the MDA/DA there are 'balked' landing procedure designs as well.
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Originally Posted by OBN
2.5% is all engine...make no mistake about that.
Let's face it, if all the engines are running, this discussion is purely hypothetical. Any modern aircraft will kill any of the requirements (even a 402). |
Sorry, but you are incorrect. This is a common misconception...but still wrong.
The climb gradient is based on normal operations, not EO operations. Just because you may be able to achieve that gradient EO is irrelevant to the regulatory environment. The NET climb profile EO is much different that the NET climb profile all engine. You are a declared emergency on EO. There is NO criteria that addresses EO parameters, therefor NEVER expect that the DA/MDA includes this emergency operation. There are 'specials' that address EO operations, but unless you have one of those specific designs, you are NOT covered for EO. Let's face it, if all the engines are running, this discussion is purely hypothetical. Any modern aircraft will kill any of the requirements (even a 402). This criteria is used to evaluate obstacles to set the DA/MDA...obstacle determine the DA/MDA. |
JAA:aircraft performance(weight/thrust)must comply with approach climb gradient(one engine at TOGA thrust and flaps 15).
For example missed approach is 3%,aircraft engine fails on final,continue on landing flaps to minima,no visual,go around to a flaps 15. Dispatch must ensure 'scheduled' weight allos the gradient for conditions at destination eta. If conditions change(weather,runway in use),crew must assure themselves of such perforlance by calculating actual single engine flaps 15 gradient using boeing onboard FCOM 'dispatch performance' tables. ICAO/FAA: no such requirement.pilot decision.i guess its all about statistics/risk assessment in their case. Flight pathobn: [QUOTE][One reason you may see different DA's can be because of extreme cold temps. There will be a DA for temps down to -20C, then another DA for temp below -20C on baro.../QUOTE] are you on drugs?:E |
there doesn't seem to be a consensus.
we use the customized 10-7 (EOSID) plates which include a temperature chart indicating weather the airplane will comply with the published missed approach OEI, but my query is regarding regulated approach weight if you may. since we are supposed to fly the eosid, the missed approach gradient shouldn't be limiting if i use common sense. i'll take it up to the company thanks for the input. |
JAA:YES REGULATED landing weight to comply with missed app climb gradient!
For 737,it is based on one engine at TOGA,flaps 15. FACT! Check the regulations!CS25 i think under destination airport. |
defacto: ???
Note on the plates the low temp limit. The criteria temperature is based on the criteria 3 GPA, effective GPA going down to 2.71. Some regulatory agencies allow the effective GPA down to 2.5, based on the same 3 GPA. Hence there can be a DA for 2.71, to meet criteria, and another for 2.5, based on temperature. |
Originally Posted by MD80FO
we use the customized 10-7 (EOSID) plates which include a temperature chart indicating weather the airplane will comply with the published missed approach OEI, but my query is regarding regulated approach weight if you may.
since we are supposed to fly the eosid, the missed approach gradient shouldn't be limiting if i use common sense. If your EOSID charts specifically mention limit weights for the missed approach (on the EOSID track), I'd say that you wouldn't have to worry about the certification missed approach gradient requirements/weights. But, you'd better ask your performance engineers if that really is the case. The other issue, as Starbear said earlier, is tracking. To use an EOSID for a Missed approach, you'd have to make sure the tracks matched. FlightPathOBN, I still reckon you've got the wrong end of the stick. That diagram you posted is totally irrelevant with all engines running (even on a 4-holer). The gradients achieved would be far in excess of what you show there. And doesn't matter how many engines are going, if I can make 2.5% I will clear the obstacles. It's up to me to organise my weight to achieve that. Obviously, the OEI is the only case I need to consider.
Originally Posted by OBN
One has to remember that the Missed and EO consider the hottest day of the year for that aerodrome. Many EO procedures in AUS use 60'/nm as climb gradients.
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For 737,it is based on one engine at TOGA,flaps 15. FACT! Ref 8260.52 and PansOps 8168. Describes terminal procedure designs and the parameters. Currently, EO operations are not included in terminal design criteria. EO are referenced in airport operations as an operator requirement, but this design must be done by others, on a specific basis. FAR Part 25 Airworthiness, describes how V 1.3 is determined. "Aircraft approach category means a grouping of aircraft based on a speed of VREF, if specified, or if VREF is not specified, 1.3 Vsoat the maximum certificated landing weight. VREF, Vso, and the maximum certificated landing weight are those values as established for the aircraft by the certification authority of the country of registry." |
The diagram was from 8260.52 in an attempt to show how the missed surface is determined, and to lead one to the criteria. The criteria is based on all engine for approach procedures. The design criteria allows for turns at 400' for which there is no design criteria to determine the turn capabilities when EO.
There is nothing in the criteria to support EO design parameters, which is why EO are custom designs. In AUS, I am very familiar with the YMML, YBBN, and YPAD. Some of the Airbus variants have 60' to 67'/nm climb gradients at EO at the high temperatures with the posted MLW. |
Some of the Airbus variants have 60' to 67'/nm climb gradients at EO at the high temperatures with the posted MLW. |
Yes, these are RNP procedures.
Normal operations easily meet the criteria at 2.5%. As I have stated, EO procedures, which are emergency based, do not have a criteria. There are no public charts to my knowledge that show an EO track. Here is a powerpoint from the FAA that describes the differences. http://www.faa.gov/other_visit/aviat...91overview.ppt Note page 20... 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: |
As far as I can tell, this thread has nothing to do with RNP procedures.
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Concur, and neither is the response...the procedures in AUS are RNP...
otherwise, the information is relevant... Did you look at the FAA powerpoint? AC120_91overview This powerpoint distinctly describes the issues... That landing wouldn't be legal because those gradients are way below the Approach Climb certification requirement of 2.1% (127ft/nm) "EOPS do NOT need to meet TERPS requirements" Look at it another way...on Final, for example a 737... Approach: Vref is flaps 30, no thrust. EO Missed climb: Stall is flaps 10... How did one get from flaps 30 to flaps 10? What happened during those 35 seconds? |
Nothing in that PP that is particularly relevant to this discussion that I can see. The thread is about following a takeoff EOSID procedure when conducting a Missed Approach.
Quote: That landing wouldn't be legal because those gradients are way below the Approach Climb certification requirement of 2.1% (127ft/nm) "EOPS do NOT need to meet TERPS requirements" |
CAAP 235-4(0)
1.1 Engine out SIDs (EOSIDs) Standard Instrument Departures (SIDs) or departure procedures (DPs) are designed in accordance with U.S. Standards for Terminal Instrument Procedures (TERPS) or ICAO Pans-Ops. These are based on normal all-engine operations and assume that the aircraft are capable of maintaining a climb profile. These departure procedures are normally published as specific routes to be followed or as omni-directional departures, together with procedure design gradients and details of significant obstacles. They are normally established for each runway where instrument departures are expected to be used and they define a departure procedure for the various categories of aircraft used. In the event of an engine failure, continued adherence to departure procedures may not be possible as SIDs or DPs do not necessarily assure that engine-out obstacle clearance requirements are met. An engine failure during takeoff is a non-normal condition, and therefore, takes precedence over noise abatement, air traffic, SID’s, DPs, and other normal operating considerations. The fundamental difference between SIDs and EOSIDs is that SIDs provides the minimum performance considerations to meet the departure requirements assuming an all engine operation whereas EOSIDs are based upon engine out performance in relation to obstacle clearance. EOSIDs can be in the form of a straight departure and or a series of turns. 7. TERPS CRITERIA VERSUS ONE-ENGINE-INOPERATIVE REQUIREMENTS. a. Standard Instrument Departures (SID) or Departure Procedures (DP) based on TERPS or ICAO Procedures for Air Navigation Services—Aircraft Operations (PANS-OPS) are based on normal (all engines operating) operations. Thus, one-engine-inoperative obstacle clearance requirements and the all-engines-operating TERPS requirements are independent, and one- engine-inoperative procedures do not need to meet TERPS requirements. Further, compliance with TERPS all-engines-operating climb gradient requirements does not necessarily assure that one-engine-inoperative obstacle clearance requirements are met. |
CAO 20.7.1b section 9 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% What is the NET? and also.. (b) a weight that will permit compliance with the take-off climb requirements mentioned in subsection 7 taking into account either ambient temperature and aerodrome elevation, or approved declared conditions; and also... (b) the height necessary to achieve obstacle clearance in accordance with paragraphs 12.1 and 12.2. and also... For the purposes of subparagraph 4.1 (ba), the take-off obstacle clearance requirements are met if the net flight path of the aeroplane, following failure of the critical engine so that it is recognised at V1 appropriate to a dry runway, would clear by at least 35 feet vertically all obstacles in the take-off area. |
I understand all that. The fact is that, at least in the vertical sense, the terrain clearance of 2.5% provided by a SID and most Missed Approach procedures is in excess of the OEI performance required for both takeoff and landing, so regardless of what is written on paper about what is designed for what, if one is able to achieve 2.5% (all-engine or OEI), one can follow the SID or published Missed Approach procedure and be "covered" (lateral tracking rules not-withstanding).
The thread issue, however, is about whether a operator can ignore the basic performance requirements for Approach Climb (2.1%) by following an EOSID (at or below the EOSID weight), during a Missed Approach. |
No....
at our company we are required to fly the EOSID in case SE missed approach at certain airports and OAT The thread is relevant. |
whether a operator can ignore the basic performance requirements for Approach Climb (2.1%) by following an EOSID (at or below the EOSID weight), during a Missed Approach.
Just to refocus - the approach and landing climb requirements are WAT limits and, as such, are built into the basic AFM calculations - you CANNOT plan to exceed WAT limits. So while the thread discussion has been quite interesting, it is essential to keep in mind that the above question is not an option - the gross weight MAY NOT exceed any of the WAT limited weights - period. |
Well, yes, and no....
There is a balance in the criteria base on worst case options. The published procedure designs are based on the coldest day recorded for the aerodrome, while the missed and departure are based on the hottest day recorded. That is why they plates show NA below and NA above. |
in the regulatory sense, can we plan to fly an approach above max approach climb limiting weight if instead of the published GA we plan for EOSID ? Wouldn't that make it something like taking off from an airport with a higher than standard (normal) SID climb gradient and planning to depart using the EOSID just to increase the payload? :confused: |
can we plan to fly an approach above max approach climb limiting weight
No - the rules require you not to exceed WAT limits. The suggested option is not an option. |
thanks for grounding this..
That is not an option, because you may have to go missed on the approach. This was a good discussion on several topics! |
because you may have to go missed on the approach.
From a regulatory point of view - irrelevant. The Design Standards mandate the WAT limits regardless of whether or not the aircraft experiences an engine failure on the day. Equally, the WAT limits are not interested in terrain - the operator/pilot have to make sure that gross weights are constrained to an extent sufficient to provide adequate climb capability on the day. |
WATS
...the limiting conditions that will satisfy the minimum second-segment climb gradient requirement at a given flap setting.... Departure Climb Gradients; 1st segment - positive 2nd segment - 2.4% one engine inop or 5.2% all engines 3rd segment - 1.2% one engine inop 4th segment - 1.2% one engine inop or 4.0% all engines Landing Climb Gradients; 1500ft above the aerodrome, a positive gradient Balked Climb - 3.2% in the landing config with all engines operating Approach Climb - one engine inop, gear up - 2.1% ASSUMING there are no obstacles...(such as terrain) |
WAT limits are a bit more general than that and, in particular, second segment WAT is only one of a number of separate WAT limits.
For instance, the current FAR 25 words are along the following lines - (a) FAR 25.119 (b) FAR 25.121 (c) FAR 25.123 As generally applies, the present rules don't apply retrospectively so, for any given Type, one needs to look up the relevant frozen Design Standards for the particular Certification. However, while the specific detail may vary historically the current rules give you a picture of something approximating what the story is for any recent Types. Obstacles are quite irrelevant to Design Standards (eg FAR 25) and don't come into play until one looks at Operational Standards (eg FAR 121). |
Concur,
From a designers perspective, many of the regs conflict...which is why it is difficult to distinctly describe a situation... Part 25 includes 25.111, and 25.125... |
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