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Approach Climb Gradient vs EOSID

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Approach Climb Gradient vs EOSID

Old 27th Mar 2011, 07:50
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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!
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Old 27th Mar 2011, 14:45
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Yes you can. Just check you are not over MTOW for that runway for given conditions.
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Old 27th Mar 2011, 17:03
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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.
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Old 27th Mar 2011, 17:25
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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.
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Old 27th Mar 2011, 18:08
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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?

I can't remeber which airfield it is now...i know i've seen the charts before....
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Old 27th Mar 2011, 21:54
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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.
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Old 27th Mar 2011, 23:35
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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 ?
I would say No. You must comply with the certification weight requirements ie be at or below Approach Climb or Landing climb limited weights, regardless of terrain. I don't believe there is any relief from the landing certification requirements based on takeoff performance ie EOSIDs. On top of that comes the potentially more-limiting Missed Approach gradient requirements that ggofpac mentions.

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.
A fire that will not go out would be considered an emergency, and there is no requirement to comply with any certification rules in that case.

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.
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Old 28th Mar 2011, 12:54
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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?
Very simple answer to that one: as you are visual after passing the higher DA/MDA you complete the landing!!!
Best RGDS
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Old 28th Mar 2011, 13:30
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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.
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Old 28th Mar 2011, 14:05
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An MD80 will easily comply with the gradient from DH on SE.
I wouldn't be so sure about that. The 717 (not the most underpowered thing in the sky) is a real dog hot n high on one engine and the 2.5% MA gradient is quite limiting sometimes.

Last edited by Capn Bloggs; 28th Mar 2011 at 23:23. Reason: added "on one engine"
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Old 28th Mar 2011, 17:41
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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.
No, this is not correct. Missed Approach is based on all-engine. MDA and DA are based on all-engine missed.

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.



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...

Last edited by FlightPathOBN; 28th Mar 2011 at 18:01. Reason: add profile
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Old 28th Mar 2011, 18:03
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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
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Old 28th Mar 2011, 18:07
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For a go around below the MDA/DA there are 'balked' landing procedure designs as well.
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Old 28th Mar 2011, 23:21
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Originally Posted by OBN
2.5% is all engine...make no mistake about that.
No it's not. The 2.5% is merely what your aircraft needs to achieve to miss the obstacles on the Missed Approach path. Nothing more, nothing less. If your aeroplane will not do that (eg with an engine out) then you have to either increase your minimum, lighten the weight so that you can make the 2.5% or, in some other way (eg company EOSID/MA procedure), get to the MSA without running into terra firma.

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).
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Old 29th Mar 2011, 00:41
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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).
The criteria assumes all engines, and a worst case scenario with aircraft class, performance loading, and temperatures.

This criteria is used to evaluate obstacles to set the DA/MDA...obstacle determine the DA/MDA.

Last edited by FlightPathOBN; 29th Mar 2011 at 00:43. Reason: illuminate
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Old 29th Mar 2011, 06:34
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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?

Last edited by de facto; 29th Mar 2011 at 14:27.
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Old 29th Mar 2011, 14:21
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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.
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Old 29th Mar 2011, 14:33
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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.
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Old 29th Mar 2011, 14:39
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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.
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Old 29th Mar 2011, 15:17
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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.
That's different. In your first post you only mentioned "EOSID" which implied you were using the takeoff EOSID and RTOW for the Missed Approach.

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.
Are you talking about Australia? Can you give an example?
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