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Go Around procedure for One Engine Out

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Go Around procedure for One Engine Out

Old 13th Aug 2019, 22:18
  #21 (permalink)  
 
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Hi Compressor Stall,

itís 2.5% by default.
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Old 13th Aug 2019, 23:55
  #22 (permalink)  
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Keep in mind that the typical miss terrain clearance analysis isn't run just by looking at a simple comparison of gradients. Usually, the miss starts higher and the analysis looks at what gradients and profile will still clear the terrain profile - ie the aircraft's clearance will decrease during the miss but not to the extent that things get exciting. OEI, a simple gradient comparison analysis generally is not going to be terribly useful for commercial operations.

Whether takoff or miss, using a simple gradient analysis, rather than a discrete obstacle approach to the problem, usually is too weight limiting.
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Old 14th Aug 2019, 00:48
  #23 (permalink)  
 
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Originally Posted by pineteam View Post
Hi Compressor Stall,

itís 2.5% by default.

Just checking - as the STD setting is 2.1%....
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Old 14th Aug 2019, 01:04
  #24 (permalink)  
 
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Qatar airways uses maximum temperatures that allow a single engine published missed approach below max landing weight published on jepp 10-7

When that is not available, the procedure is to use the maximum level of altitude (fly smart takeoff performance) to determine weather the missed approach altitude or the applicable MSA(whichever is lower) can be achieved within 10 minutes, if it is lower then you apply 10-7.
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Old 14th Aug 2019, 01:55
  #25 (permalink)  
 
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This is my personal take, not authorized or anything.

An EOSID assumes the worst possible conditions at take off (i.e. high temperature, Max take off weight etc.). Therefore an EOSID can always be used as a missed approach with a single engine.

If you assume go around with a single engine at the time that results in the aircraft being at the lowest possible altitude i.e. in the flare with a bounce, then once you are airborne it is esentially as though you have rotated at the start of the runway. If the EOSID can cater for you taking off at the DER with single engine and the worst conditions it can cater for any condition similar or better than that. Just ensure acceleration is done at the same alt as you would do on single engine take off.
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Old 14th Aug 2019, 02:58
  #26 (permalink)  

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Originally Posted by compressor stall View Post
Without checking, what is the default climb gradient shown in the Flysmart landing module (in flight)?
2.1 normal and 2.5 LVP ops. IIRC.
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Old 14th Aug 2019, 07:17
  #27 (permalink)  
 
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As I understand it, the default setting is 2.1%. You have to manually enter 2.5% for the LVP, as the App has no idea if itís LVP or not.

Thereís no way I can see to change this default in the back end either.
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Old 14th Aug 2019, 07:31
  #28 (permalink)  
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An EOSID assumes the worst possible conditions at take off (i.e. high temperature, Max take off weight etc.). Therefore an EOSID can always be used as a missed approach with a single engine.

Not quite the case. Configuration and configuration change, speed delta and height loss (?) / distance to get to a suitable comparison configuration and speed. Can get to be an involved analysis and, generally, not addressed in AFM data so it's back to basics and some simple flight test number work.
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Old 14th Aug 2019, 08:06
  #29 (permalink)  

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Originally Posted by compressor stall View Post
As I understand it, the default setting is 2.1%. You have to manually enter 2.5% for the LVP, as the App has no idea if it’s LVP or not.
That the 2.1 changes automatically to 2.5 when CAT II approach type is selected in the other box was without checking , a memory from longer ago. The softair's explanation at the time was those were the regulatory (cs-25 or similar) figures for the aeroplane, unlike PANS-OPS values, hence it comes out of the factory that way. Pronto we changed both in the configuration file to 2.5 and set the calculation altitude at 1500 AAL with the help of PPM.

I only have access to fragments of the updated SW from a different source these days (back to RTOW charts, what a load of fun they are) and the one I have behaves differently - upon selecting CAT II the 2.1 remains and gets rejected as the entry filter is still set at 2.5. Whether or not these can still be pre-configured at the present version I have no clue.


Last edited by FlightDetent; 14th Aug 2019 at 09:42.
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Old 14th Aug 2019, 09:05
  #30 (permalink)  
 
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Originally Posted by FlightDetent View Post
2.1 normal and 2.5 LVP ops. IIRC.
According to Doc 8168 Vol. 1 the number is 2.5 regardless of the type of approach.
Could you give any reference for this 2.1% (other than the App)?

6.1.7 Missed approach gradient
6.1.7.1 Normally procedures are based on a minimum missed approach climb gradient of 2.5 per cent. A gradient of 2 per cent may be used in the procedure construction if the necessary survey and safeguarding have been provided. With the approval of the appropriate authority, gradients of 3, 4 or 5 per cent may be used for aircraft whose climb performance permits an operational advantage to be thus obtained.
6.1.7.2 When a gradient other than 2.5 per cent is used, this is indicated on the instrument approach chart. In addition to the OCA/H for this gradient, the OCA/H applicable to the nominal gradient will also be shown.
6.1.7.3 Special conditions. It is emphasized that a missed approach procedure which is based on the nominal climb gradient of 2.5 per cent cannot be used by all aeroplanes when operating at or near maximum certificated gross mass and engine-out conditions. The operation of aeroplanes under these conditions needs special consideration at aerodromes which are critical due to obstacles on the missed approach area. This may result in a special procedure being established with a possible increase in the DA/H or MDA/H.
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Old 14th Aug 2019, 09:30
  #31 (permalink)  

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poldek77 agreed, see my post #7. It's airworthiness not flight operations for the 2.1%.

EASA CS 25.121 Climb: one-engine inoperative
(d) Approach. In a configuration corresponding to the normal all-engines operating procedure [...]
(1) The steady gradient of climb may not be less than 2∑1 % for two-engined aeroplanes [...], with
- (i) The critical engine inoperative, the remaining engines at the go-around power or thrust setting;
- (ii) The maximum landing weight;
- (iii) A climb speed established in connection with normal landing procedures, [...] and
- (iv) Landing gear retracted.

You make me go research things! Oh well then, another file on the drive.
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Old 14th Aug 2019, 10:03
  #32 (permalink)  
 
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Flight Detent - my apologies - I forgot the CAT II button was there... we don't do them so it's a section I glaze over!!
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Old 14th Aug 2019, 10:33
  #33 (permalink)  

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On second thought, we may had hacked the LPC.NG configuration files directly, as opposed to changing the setup via the admin module. Hope you find what you need, the value of 2.1 is of absolutely no use to operator staff and their crew.
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Old 14th Aug 2019, 11:05
  #34 (permalink)  
 
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Originally Posted by FlightDetent View Post
poldek77 agreed, see my post #7. It's airworthiness not flight operations for the 2.1%.

EASA CS 25.121 Climb: one-engine inoperative
(d) Approach. In a configuration corresponding to the normal all-engines operating procedure [...]
(1) The steady gradient of climb may not be less than 2∑1 % for two-engined aeroplanes [...], with
- (i) The critical engine inoperative, the remaining engines at the go-around power or thrust setting;
- (ii) The maximum landing weight;
- (iii) A climb speed established in connection with normal landing procedures, [...] and
- (iv) Landing gear retracted.

You make me go research things! Oh well then, another file on the drive.
Now it's clear for me - many thanks!
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Old 14th Aug 2019, 11:40
  #35 (permalink)  
 
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Originally Posted by FlightDetent View Post
On second thought, we may had hacked the LPC.NG configuration files directly, as opposed to changing the setup via the admin module. Hope you find what you need, the value of 2.1 is of absolutely no use to operator staff and their crew.
Yes - I'll do some more digging, but when I set up Flysmart ca. 5 years ago changing the min 2.1% wasn't an admin option. It's not my area any more, but I'll have a nosey into the files and see if its changed.
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