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BA's 80 Knot Call

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BA's 80 Knot Call

Old 5th Feb 2007, 08:53
  #21 (permalink)  
 
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On the bus half deflection forward stick is taken prior to setting the T/O thrust (full deflection for >20 kt X-wind or and tail wind). This is to keep the N/W firmly on the ground for steering during the time the pitch power couple would try to lift the nose. At 80 knots the NHP calls and checks the HP releases, slowly, the forward pressure. This tells the NHP the HP is 'alive' and gets rid of the nose wheel loading as, above 80kts, the aerodynamic effects of the rudder outweigh the effects of the nose wheel steering.
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Old 6th Feb 2007, 00:51
  #22 (permalink)  
 
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TAC INOP,

We do not call FMA changes when they should happen on the B777 sir.
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Old 6th Feb 2007, 02:46
  #23 (permalink)  
 
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Sir (nice one)...we call FMA every time it changes, as part of crew awhereness

and I still cant believe the bit about warning inhibs at 80 kts...cautions ok, but warnings.....
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Old 6th Feb 2007, 14:28
  #24 (permalink)  
 
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TAC inop,

On the BA 777 the PM calls 80 kts and both PM and PF would expect to see the 'HOLD' FMA, they just don't verbalise it, thats all. For your interest, we call them NHP (non-handling pilot) and HP (handling pilot) respectively.

I cant see the post about "the bit about warning inhibs at 80 ts...cautions ok, but warnings" (deleted maybe?) but that is wrong. On the BA 777 the Master Caution lights and beeper are inhibited at 80 kts. The Master Warning Lights and Fire Bell and Siren are inhibited at V1.
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Old 6th Feb 2007, 14:41
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teamilkand sugar wrote

'A whole bunch of things happen at 80kts...(Boeings anyway)
1. Incapacitation check
2. Instrument x-check
3. Stopping for "any abnormality" has ended, and we now only stop for more serious things...
4. Master caution and master warning "attention getters" (lights and aurals) now inhibited
5. The autothrottle system disengages from the throttle servo gears and so cannot move a thrust lever until new selction on Thrust management coputer (earlier versions, or MCP on later models)'


ok...now I am talking about item 4...now, that aint right, not at 80 for warnings

further, to reflect on the thread itself, I sugested early that maybe BA had a call of 'hold' to respond to the 80kt call ... but I guess you just dont respond at all...does seem strange, but hey, whatever rings BA's bells
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Old 6th Feb 2007, 22:07
  #26 (permalink)  
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you are right no reply to the 100 above call but at DECIDE call if the PF does not responed then the PNF will exicute a goround.
Further to the above (BA use "50 above"), if no reply is received to "Decide" on a Cat 3 approach, in BA the co-pilot will land as it is considered safer than a solo go-around.

The calls within BA (from the Non-Handling Pilot) are "Power Set", "80 knots", "V1" (if applicable), "Rotate", "Positive Climb" ... and of course "Stop".

The "Stop" call is perhaps the most contentious. Obviously, it can be called by the Captain for any reason, although above 80 knots it would most likely be for "multiple failures". However, unlike in some companies, it can be called by the co-pilot for any of the following:

i) Any fire
ii) Engine failure (two parameters, one on the panel)
iii) Configuration warning
iv) Blocked runway *
v) Control difficulties *
vi) "Monitor Radar Display" auto-callout **
vii) "Windshear Ahead" auto-callout **

* If handling
** Where fitted
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Old 7th Feb 2007, 01:11
  #27 (permalink)  
 
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Also, on a CAT3 No DH approach there will be no "50 above" call/autocall (or 100 above for that matter). So by the time the F/O notices the Capt is incapacitated the aircraft has landed itself! Just select reverse, disconnect the A/P, override autobrake as appropriate and ask ATC for assistance and medical as required. A G/A would really screw up the Captains chance of survival and increase the F/Os workload tenfold.
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Old 7th Feb 2007, 07:58
  #28 (permalink)  
 
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All these are indeed quite correct, but to answer the initial question: Why 80 KTS, as it might have been chosen 70, or 90, 100, 85....
If I remember well my early aviation days, on a 707, there was no link between the rudder pedals and the nosewheel, as on later aircraft, and no tiller on the right side; during initial take off roll, and especially with cross wind, the captain had to keep his right hand on the thrust levers and his left hand on the tiller to keep the plane on the centerline using the tiller, while the FO would hold a forward pressure on the column, and this until the rudder became aerodynamically effective to be used for directioanal control on the runway. That speed was 80 Kts, which the FO would call so the captain could move his left hand from the tiller to the column. From there on "80Kts" became a "traditional" speed to call and to use for all the other purposes you all guys have mentioned.
Et voila, madame, pourquoi votre fille est muette.
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Old 7th Feb 2007, 09:04
  #29 (permalink)  
 
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refer to my post above
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Old 7th Feb 2007, 10:42
  #30 (permalink)  
 
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Also for most types RTO or autobrakes max is armed prior to this speed, also for certification, takeoff power must be set by that speed.

Also in low vis, takeoff should be continued after this speed if vis reduces below takeoff minima, because it is safer than the RTO in this case.
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Old 7th Feb 2007, 13:12
  #31 (permalink)  
 
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) Any fire
ii) Engine failure (two parameters, one on the panel)
iii) Configuration warning
iv) Blocked runway *
v) Control difficulties *
vi) "Monitor Radar Display" auto-callout **
vii) "Windshear Ahead" auto-callout **
I would have thought the captain, under the conditions above, would make his own decision to reject the take off without having a startled squawk of "Stop" from the copilot to tell him what to do - or should not do - as may be the case at the time..
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Old 7th Feb 2007, 13:15
  #32 (permalink)  
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Rather depends who notices first.

Also, if the captain isn't handling and is looking in at the engine instruments I would have thought the FO calling stop for a blocked runway or control difficulties makes a lot of sense.
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Old 7th Feb 2007, 18:19
  #33 (permalink)  
 
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Here we go again, just because "our" (i.e.BA's) SOP is different to your's then it is "out of this world". Why the emotive language? The instances an F/O can call stop are well defined and seem to work fine.
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Old 7th Feb 2007, 20:34
  #34 (permalink)  
 
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RTO, I'll give you that BA SOP's might not seem sensible for someone who doesn't work with em on a daily basis, but they are bloody good once you get the hang of em.
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Old 7th Feb 2007, 23:46
  #35 (permalink)  
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"I fly and you play with the thrust levers" thing?
I think that went with the Flight Engineers (and probably the VC10 - ask the RAF).
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Old 8th Feb 2007, 00:04
  #36 (permalink)  
 
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just back to the core for a moment.... FCTM 3.5 states '...PM should anounce passing 80 kts, and the PF should verify....etc'
So, that is what Mr Boeing has to say about it
ibid
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Old 8th Feb 2007, 01:02
  #37 (permalink)  
 
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TAC inop,
...PM should anounce passing 80 kts, and the PF should verify....
Why should he/she announce something that which you both normally expect to see?

British Airways don't invent their own SOPs. BA consults with the manufacturer (Boeing or Airbus) and then decides on the SOP providing this is in agreement with the manufacturer.

At the end of the day, how many times has a B777 aborted take-off because the FMA didn't annunciate 'HOLD' at 80kts eventhough take-off power was correctly set?
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Old 8th Feb 2007, 10:36
  #38 (permalink)  
 
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On 737 the call should be made at 80 kts ,and the other pilot should check his speed and answer 'checked' . If the speed is not right,he should abort the take off.We had a safety presentation done by a Boeing safety pilot,and it was obvious that it's much safer to abort instead of continuing with unreliable speed (observed by high speed difference at 80 kt call)
The 'hold ' call is not required by Boeing , it must be monitored. The absence of 'hold' is not a reason for RTO , but the pilots must closely monitor the a/t operation during take-off (so it doesn't reduce power due to any fault )
I had some fo's who were doing the 80 kt call :" 80..thrust hold "...so I asked them what if you don't see 'hold' ? you reject? And I've surprised some of them, cause they were doing the check without really thinking of it.
Elroy,on the 737 the autobrake arms at 90 kt.
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Old 8th Feb 2007, 12:00
  #39 (permalink)  
 
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More importantly, autobrake RTO functions above 85 kts on B777.

The BA SOP is to apply full reverse above 80 Kts in an RTO, and reverse idle below 80. Therefore the 80 kts call by PNF serves as a good "reminder to self" as to how much to apply if stop is called.
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Old 10th Feb 2007, 11:43
  #40 (permalink)  
 
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TAC Inop

Sorry for the delay...been on a trip.

You are indeed correct. Too much ale pre-post!
Cautions inhibited from 80kts, WARNINGS from rotation (B757-767) or V1 depending on systems fit.

Thanks for the spot & clarification - I'll edit my post.

Last edited by teamilk&sugar; 10th Feb 2007 at 12:03.
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