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Final approach speeds

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Final approach speeds

Old 14th Nov 2006, 12:02
  #21 (permalink)  
 
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.4, just be glad you gave up gatwick. I'd say most aircraft are 145/150 IAS at 4dme there.
2 this morning (A330's) slowed to 160kts without being told to. First one I told him of his error then instructed him to maintain the 160 to 4 dme, next time I check his speed he's 140 at 5!

Heathrow had a loss of separation last week with 2 aircraft on base leg caused entirely by the distraction of taking corrective action with an aircraft that slowed early.

You can't even follow a pattern of aircraft types or airlines that are particularly bad, in my experience it comes down to individual crews not following their clearance. Filling in reports isn't the way forward, with our new electronic reporting system it takes me half an hour to file a report, that's my fatigue break. The best way is to reposition the offending aircraft or send it around but it's not always possible when you've traffic close behind.

If 160 to 4 cannot be achieved then we should be talking about bringing in a new standard and accept the inevitably lower movement rates but it's dangerous to be issued and readback a clearance of 160kts to 4 when you have no intention of following it.
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Old 14th Nov 2006, 12:13
  #22 (permalink)  
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DP:

Spot on. We have to resolve this professionally, adjusting the procedures if they are not leaving us sufficient scope.

Callo:

I'm not sure if the Tower have the Mode S readouts that we now get so perhaps they are not always able to tell who the offending party is. Radar derived Ground speed is very inaccurate.

Personally, I hate the idea of emabarrassing anybody on the r/t. I think the paper work route is probably the right way but that seems so official and heavy. As DP points out, these days it takes most of your break.

.4
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Old 14th Nov 2006, 12:15
  #23 (permalink)  
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Found one of the threads
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Old 14th Nov 2006, 12:49
  #24 (permalink)  
 
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We don't have Mode S speed readouts in the tower, only radar derived GS.

Unfortunately, there are one or two ATCOs here who believe that if an aircraft (especially BA short haul for T4) rolls to A10E on 27R then they must be taking the . The comments regarding "Do you have a tail wind?" or "Do you have a braking problem" are not helpful.
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Old 14th Nov 2006, 14:08
  #25 (permalink)  
 
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Originally Posted by Janspeed View Post
Speedbrakes it is!
That's what they're for!
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Old 14th Nov 2006, 14:25
  #26 (permalink)  
 
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Originally Posted by Janspeed View Post
Generally from 250-220 kts for the hold (eg Ock) that speed usually implies Flaps 1 setting as mnm clean can go up to +235 kts.......
235Kts is a typical clean speed for a B744 at high landing weights. I have frequently requested a higher speed before entering a hold, even up to 240 kts. Providing ATC know it is not a problem. There has never been occasion when such a request was refused. This may not be the case at other airports such as EGKK. The argument regarding an inability to advise ATC is without foundation. There are plenty of occasions before becoming established when you are able to advise of your operational requirements. Tag it onto the end of a readback. There is no excuse for accepting a clearence and then knowingly not comply with it. You wouldn't cross the NAT tracks at .84 when your clearence is .86. Is there no flexibility on SOP's? Our company SOP is to cruise at ECON speed. If ATC request a specific speed then I will do my best to comply. If your Company SOP is to put the gear down and flap XX and fly the required bug speed at a specific point then frankly there is no hope!!!
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Old 14th Nov 2006, 14:27
  #27 (permalink)  
 
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Originally Posted by IcePack View Post
Bit of tail waging the dog here.
Not all pilots are of the same caliber.
If a pilot feels safer slowing down as per company SOP's then so be it flight safety is paramount.
Only excuse to not telling ATC is because you can't get a word in edgways.
You are quite right Ice Pack - however
It is speed control and not speed advice - no pilot would dream of stopping climb or descent at a different level to the clearance issued without reference to ATC, or deviate from a heading without reference - so why do crews feel that they can fly whatever speed they wish to without advising ATC?
No controller would refuse you the speed you want - but you have to tell us
Otherwise the one aircraft you are flying is nicely adhering to company SOP's for YOUR flight safety - but what about the aircraft behind you that is no longer separated and potentially getting vortex wake off your aircraft - and no longer in the comfort zone of safe flight

We can only achieve minimum spacing if we have all the information available, otherwise - as one post said there will less folk who will be prepared to vector to minimum spacing.
At a place like Heathrow anyone who works there could imagine the knock on affect that will have - and the reason for the increase in spacing? - Flight Safety is paramount

louby
(off the soap box )
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Old 14th Nov 2006, 15:05
  #28 (permalink)  
 
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30W
- just because you put the 'Gear Down' doesn't mean you MUST slow below 160kt! Configure as required before 4d except for final landing flap, but MAINTAIN 160kt to 4d. At 4d reduce and complete landing config. With the gear already down, speed will reduce perfectly well to complete a stabilised approach.
You have obvously never flown a A319 and have to comply with BA's "stable by 1000'" criteria

I have flown in and out of LHR for nearly 12 years. I can confidently state I have never flown 160 to 4D, nor have ever seen anyone do so. It maybe BA only, but we ALL slow up early - we have to (usually slow from 160K ~4.5d - 5d). 120.4 is raising a valid point that what ATC expect, and our SOPs are not compatible... and Mode S and whatever changes are inbound to LHR will highlight these differences, and something will have to change...

You should not be in a position where every approach requires speedbrake to comply with a profile... apart from it destabilising the approach, the tree huggers would rightly jump up and down
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Old 14th Nov 2006, 15:23
  #29 (permalink)  
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It is beginning to sound like the requirements of modern aircraft and the ATC system have got out of sync. ATC precedures that require air crew to fly outside SOPs are not acceptable. If that is the current position, as NOD seems to suggest, then we need to look again at the whole issue of speed on final but the cost could likely be a drop in capacity.

.4
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Old 14th Nov 2006, 15:25
  #30 (permalink)  
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120.4 is raising a valid point that what ATC expect, and our SOPs are not compatible
- 3 solutions, then?

1) ASR (MOR?) saying that you cannot comply with ATC requirements due to company SOPs
2) Notify ATC on every check-in with director of same
3) ATC change to 170 to 5 or something BA can hack.

In 'days of old', 1000' was a 'review point', and 500' was the 'decider'. Has that changed?
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Old 14th Nov 2006, 15:42
  #31 (permalink)  
 
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In 'days of old', 1000' was a 'review point', and 500' was the 'decider'. Has that changed?
Still essentially the same, except the 1000' is being leaned on more. At one stage we had to ASR each time we were not stable at 1000' ! Use of speedbrake <1000' gets you a b*llocking, and if anything else happens, and they find you not stable by 1000'... then the words "poor" seem to crop up in the Fleet Mag writeup, and an invitation to contribute to the next edition
Don't get me wrong, I am often not quite sorted by 1000', and take your attitude above. However, as I said above, we should not have an SOP and ATC requirement that are not compatible... and where a Training System specifcally tells you what "160 to 4D" is to be interpreted as
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Old 14th Nov 2006, 15:51
  #32 (permalink)  
 
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Originally Posted by NigelOnDraft View Post
I have flown in and out of LHR for nearly 12 years. I can confidently state I have never flown 160 to 4D, nor have ever seen anyone do so.
Are you sure about that NoD? I flew the 319 for 5 years (perhaps including a tour with you) and 160 to 4 is achievable unless you are very light (in which case I always mentioned the Vapp to Director). It requires flap 3 and the gear down with the power up then a judicious timing of the managed speed selection at somewhere between 4.5 - 4d so that the engines go to idle and you cross 4d with the speed at 160kts but the green arrow pointing down. Granted this was tricky when the engines had to be at power at 1000ft but once that requirement was removed and idle power at 1000ft was permissible it became a doddle.

Originally Posted by Bearcat
which is more important?....using speed brake to slow for 180 to 160 with insignif noise consequences....or do nothing and grimice and watch the speed painstakingly slow to 160....by that time your at 4 miles......
Have you flown an A319? Using the speedbrake at 180kts produces a lot of noise, an uncomforable nose down pitching moment and does absolutely nothing to your speed. The only thing that slows an A319 effectively below 200kts is the gear.
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Old 14th Nov 2006, 15:53
  #33 (permalink)  
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Originally Posted by Porco Rosso View Post
I think the AIP says someing like "must be flown as accurately as possible", there's certainly no 10 knot tolerance as far as we're concerned.
All the books over here state the +/- 10 knot tolerance, so I'm guessing it's probably a splash over from that.
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Old 14th Nov 2006, 16:02
  #34 (permalink)  
 
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IcePack is correct...tail wagging the dog, and whinging from ATC.
The aircraft Commander decides what speed to fly on final (within reason) and he should absolutely NOT be put in a position of ignoring or violating his companies laid down procedures, just because an air traffic controller can't do his job properly.

Now, I have flown into LHR for many years in the past, and indeed have had the pleasure of doing so in a very versatile aeroplane...TriStar.
160 to 4, no problem, nor is 180 to 4.
Tell me the speed, I fly the speed.
However, some other designs clearly are not so versatile, SO it is up to ATC to make accomodations.
IF they cannot, they should find another job.

If, on the other hand, ATC cannot for some reason accomodate, then airline companies should be told they must shift their scheduled service somewhere else.
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Old 14th Nov 2006, 16:02
  #35 (permalink)  
 
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Hello Chaps,
Very interesting! Am I understanding this. A lot of pilots are saying that they are knowingly not complying with mandatory ATC instructions and are knowingly endangering aircraft that are following them AND they are not advising ATC that they cannot/will not comply with an ATC instruction, contrary to the ANO/UKAIP.
How would you feel in an A319 if the B747 in front of you did that and we did not notice as you hit its vortex wake at 1,000ft?
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Old 14th Nov 2006, 16:17
  #36 (permalink)  
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Wow 411A, talk about missing the point in a huge way

A Heathrow bod remind me.........was it BA or BMI when they got those shiny new 737s that were requesting 170kts to 4 DME (something to do with extending the gear on final)? Thing is, they would ask on first contact and you could plan for it (they didn't ask for it all the time)

The issue being discussed is fluctuations in speed without informing ATC. If it can't be done or something different is required, say someting and it can be planned (there's that word again) for. Nobody is looking to push anyoone outside of SOPs or performance envelopes, just trying to play the game together. I think you'll find those controllers "who can't do their jobs properly" may surprise you.......or pull your ass out of the sequence to be repositioned for dropping the controller and the guy following in the s***.
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Old 14th Nov 2006, 16:33
  #37 (permalink)  
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Jerricho - the 170 to 5 request was due to the change by Boeing to 737 'Classic and Jurassic' min flap speeds which meant that whereas 'before', 160kts could be flown 'gear up', now it needs gear down. The 'NG' can manage without. Its all on the other thread.

NOD - we used to manage in the 'Jurassic' 737 with Vref as low as 118kts!

In the case I mentioned at BRU I ASR'd it and asked for 'advice' on how the company wanted me to fly the approach. Pure coincidence, I know, but shortly after that BRU dropped the requirement.

A colleague of yours on another thread mentions the managers
trousering
large bonuses. Why not get them to earn a bit of them? If they 'chide' you for your 1000' performance ask them how you SHOULD fly it.

In any case, slowing to 150 at 5D makes very little difference to spacing - work it out guys. The original post here was about apparent blatant disregard for ATC speed control.
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Old 14th Nov 2006, 16:33
  #38 (permalink)  
 
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The 319 is most unlikely to catch the 747 given their different handling characteristics. I've flown both so I know. I've also experienced reduced seperation and the answer is to proceed with caution. Just because you're a bit close doesn't mean you are going to fall out of the sky.
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Old 14th Nov 2006, 16:38
  #39 (permalink)  
 
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Some assumptions on this thread are worrying.

Porco Rosso,

Just as an aside they've changed the rules for 2.5nm spacing and we're now going to be able to do it much more often than we have in the past.
Not sure what you guys have been told, but this is certainly not the case. The rules have been changed so as to, in effect, 'legalise' the situations where FIN has aimed for 3 and got anywhere between 2.5 and 3. The inbound spacing to LL will still be 3 miles, whereas separation can now legally be anything down to 2.5 miles. The rules on when we adopt 2.5 miles spacing have not changed.

120.4, anytime you want to refuse doing 2.5 is fine by me!!!

411A, you're coming down the ILS at 160 to 4 in your lovely old L1011, as instructed, with a medium 5 miles behind you, and an A320 now about 2.5 miles in front of you which has just reduced back to 120kts at 6 miles rather than 4 without telling us. Please tell us all how we can 'accomodate' that to your satisfaction

Last edited by Gonzo; 14th Nov 2006 at 18:33.
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Old 14th Nov 2006, 16:42
  #40 (permalink)  
 
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120.4
"...As a general rule we know that B757s are slow inside 4 and that B773s & MD11s are quick; we know that the A319 is slippery and difficult to slow down..."
...OK, but keep in mind that Vref [approach speed] for any airplane can vary, depending upon landing weight; in the case of a 74, Vref can vary in excess of 35Kts.
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