Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Go Around procedure for One Engine Out

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

Go Around procedure for One Engine Out

Thread Tools
 
Search this Thread
 
Old 13th Aug 2019, 22:18
  #21 (permalink)  
 
Join Date: Jul 2006
Location: Somewhere over the rainbow
Posts: 946
Likes: 0
Received 0 Likes on 0 Posts
Hi Compressor Stall,

it’s 2.5% by default.
pineteam is offline  
Old 13th Aug 2019, 23:55
  #22 (permalink)  
Moderator
 
Join Date: Apr 2001
Location: various places .....
Posts: 7,187
Received 97 Likes on 65 Posts
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.
john_tullamarine is offline  
Old 14th Aug 2019, 00:48
  #23 (permalink)  
 
Join Date: Feb 2000
Location: 500 miles from Chaikhosi, Yogistan
Posts: 4,295
Received 139 Likes on 63 Posts
Originally Posted by pineteam
Hi Compressor Stall,

it’s 2.5% by default.

Just checking - as the STD setting is 2.1%....
compressor stall is offline  
Old 14th Aug 2019, 01:04
  #24 (permalink)  
 
Join Date: Apr 2006
Location: Asia
Age: 49
Posts: 524
Likes: 0
Received 0 Likes on 0 Posts
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.
MD83FO is offline  
Old 14th Aug 2019, 01:55
  #25 (permalink)  
 
Join Date: Apr 2009
Location: Canada
Posts: 611
Likes: 0
Received 0 Likes on 0 Posts
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.
Airmann is offline  
Old 14th Aug 2019, 02:58
  #26 (permalink)  

Only half a speed-brake
 
Join Date: Apr 2003
Location: Commuting not home
Age: 46
Posts: 4,321
Received 3 Likes on 3 Posts
Originally Posted by compressor stall
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.
FlightDetent is offline  
Old 14th Aug 2019, 07:17
  #27 (permalink)  
 
Join Date: Feb 2000
Location: 500 miles from Chaikhosi, Yogistan
Posts: 4,295
Received 139 Likes on 63 Posts
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.

There’s no way I can see to change this default in the back end either.
compressor stall is offline  
Old 14th Aug 2019, 07:31
  #28 (permalink)  
Moderator
 
Join Date: Apr 2001
Location: various places .....
Posts: 7,187
Received 97 Likes on 65 Posts
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.
john_tullamarine is offline  
Old 14th Aug 2019, 08:06
  #29 (permalink)  

Only half a speed-brake
 
Join Date: Apr 2003
Location: Commuting not home
Age: 46
Posts: 4,321
Received 3 Likes on 3 Posts
Originally Posted by compressor stall
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.
FlightDetent is offline  
Old 14th Aug 2019, 09:05
  #30 (permalink)  
 
Join Date: Sep 2007
Location: EU
Posts: 155
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by FlightDetent
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.
poldek77 is online now  
Old 14th Aug 2019, 09:30
  #31 (permalink)  

Only half a speed-brake
 
Join Date: Apr 2003
Location: Commuting not home
Age: 46
Posts: 4,321
Received 3 Likes on 3 Posts
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.
FlightDetent is offline  
Old 14th Aug 2019, 10:03
  #32 (permalink)  
 
Join Date: Feb 2000
Location: 500 miles from Chaikhosi, Yogistan
Posts: 4,295
Received 139 Likes on 63 Posts
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!!
compressor stall is offline  
Old 14th Aug 2019, 10:33
  #33 (permalink)  

Only half a speed-brake
 
Join Date: Apr 2003
Location: Commuting not home
Age: 46
Posts: 4,321
Received 3 Likes on 3 Posts
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.
FlightDetent is offline  
Old 14th Aug 2019, 11:05
  #34 (permalink)  
 
Join Date: Sep 2007
Location: EU
Posts: 155
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by FlightDetent
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!
poldek77 is online now  
Old 14th Aug 2019, 11:40
  #35 (permalink)  
 
Join Date: Feb 2000
Location: 500 miles from Chaikhosi, Yogistan
Posts: 4,295
Received 139 Likes on 63 Posts
Originally Posted by FlightDetent
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.
compressor stall is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.