EGLL Director Answer...
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Maneuvering speeds...
Good Question, in fact, I had been mulling that one over before writing in the forum. The -300ER is a heavier aircraft, thus the flaps up maneuvering speeds are higher. I can remember my situation from last week. We were about 15,000 Kgs under max weight, I believe. The Flaps UP maneuvering speed is always based on Flaps 30 + 80 (Vref30+80), each subsequent flap maneuvering reduction comes down in 20K increments, so Flap 1 maneuvering would be Vref30+60.
In last weeks case, I believe we were given 220Knots at LAM, our Vref 30 speed was 143 Knots...Thus...Vref 30 + 80 = 223..which meant (and I did), I had to use Flap 1, so I had the proper speed. I believe I was given 200 next, which had me back at Flap 5. I don't 'cheat' with the speeds, but I thought if ATC could only bump up the maneuvering speeds by 3-5 knots, it would save some fuel because of the extra drag created with the LEDs hanging out.
I've always felt it important that the guys/gals who fly and the guys/gals who do the controlling, be able to sit down and talk these little issues out, so that it works best for both parties. Years ago, I was on just such a committee...I found out that you people really can stow the 'suds'! LOL
In last weeks case, I believe we were given 220Knots at LAM, our Vref 30 speed was 143 Knots...Thus...Vref 30 + 80 = 223..which meant (and I did), I had to use Flap 1, so I had the proper speed. I believe I was given 200 next, which had me back at Flap 5. I don't 'cheat' with the speeds, but I thought if ATC could only bump up the maneuvering speeds by 3-5 knots, it would save some fuel because of the extra drag created with the LEDs hanging out.
I've always felt it important that the guys/gals who fly and the guys/gals who do the controlling, be able to sit down and talk these little issues out, so that it works best for both parties. Years ago, I was on just such a committee...I found out that you people really can stow the 'suds'! LOL
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If you want to keep minimum clean, and that speed is slightly above 220kts, then just tell us and we will 99% of the time have no problems with you flying slightly faster. As a standard, we are now told to instruct 744's to fly at minimum clean as opposed to 220kts, as they generally have a min clean speed of between 220 and 230kts.
I was always taught that 777-300s also had a slightly higher min clean speed, so as long as I remember, I generally always give them 230kts instead of 220.
I was always taught that 777-300s also had a slightly higher min clean speed, so as long as I remember, I generally always give them 230kts instead of 220.
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It's nice to see a useful tread on pprune!
The VNAV path indicator is quite nice sometimes, but still very much a garbage in, garbage out device! I keep telling myself I'm going to put a post-it over it sometime to force myself not to be so lazy! I really like the half of the CAS equation - will try that one tomorrow..
As quite a newbie to this, I'm still trying to perfect my "holy grail" descents into the less busy airports with idle thrust from TOD to gear down - needless to say some days are better than others, e.g. Rwy05 today in STN, they generally need us to get down quickly to 3000ft on the downwind leg, but then you are cleared to 2500 which is platform altitude and quite a few track miles away. I know using vertical speed and say 200fpm is still technically a CDA, its still using quite alot of thrust and therefore fuel than idle.
I've been told to go min clean, which is fine, but what about these exact 180kts and 170kts to 5 miles etc, e.g. Today Flap 1 was 185, does it make a big difference? I've heard the +/- 10kts being mentioned but also heard that isn't the case, and with the enhanced Mode S, can some of the radar controllers see what speed we've selected on there?
Sorry for a million questions!
The VNAV path indicator is quite nice sometimes, but still very much a garbage in, garbage out device! I keep telling myself I'm going to put a post-it over it sometime to force myself not to be so lazy! I really like the half of the CAS equation - will try that one tomorrow..
As quite a newbie to this, I'm still trying to perfect my "holy grail" descents into the less busy airports with idle thrust from TOD to gear down - needless to say some days are better than others, e.g. Rwy05 today in STN, they generally need us to get down quickly to 3000ft on the downwind leg, but then you are cleared to 2500 which is platform altitude and quite a few track miles away. I know using vertical speed and say 200fpm is still technically a CDA, its still using quite alot of thrust and therefore fuel than idle.
I've been told to go min clean, which is fine, but what about these exact 180kts and 170kts to 5 miles etc, e.g. Today Flap 1 was 185, does it make a big difference? I've heard the +/- 10kts being mentioned but also heard that isn't the case, and with the enhanced Mode S, can some of the radar controllers see what speed we've selected on there?
Sorry for a million questions!
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I've been told to go min clean, which is fine, but what about these exact 180kts and 170kts to 5 miles etc, e.g. Today Flap 1 was 185, does it make a big difference? I've heard the +/- 10kts being mentioned but also heard that isn't the case, and with the enhanced Mode S, can some of the radar controllers see what speed we've selected on there?
If you wish/need to fly a slightly different speed just advise when asked to maintain a particular speed. The exception would be on final app where we could do with knowing before vectoring you .1nm over the vortex gap behind something else that you can't do e.g. 160 to 4.
The mode s shows us the aircraft's IAS as of the last radar interrogation, not the selected speed - so there's no cheating!! We do see MCP selected level. We can also see aircraft-derived ground speed, and mag heading. If we 'hook' the aircraft we can also see aircraft ID, ROC/ROD amongst others - see here:-
Mode S
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Ballyboley,
"I really like the half of the CAS equation"
It should be half the groundspeed (not CAS) and multiply by 10 to get a 3deg ROD. (same as 5* GS). It's easy to do quickly and great for descent, non-prec app etc.
I don't think CDA's are possible to SS 05 at all times and I don't think the approach you did was expected to be a CDA either. I was told it was due to airspace restrictions to the south. We need a SS director guru to correct me on this.
Could the same or similarly informed Guru tell us who is are the worst at sticking to speeds especially 170 to 5 or 160 to 4? It is amazing how close some a/c get even when you have been sticking well to the speeds. Now and then we keep 160 to 2 (or 170 to 3) to compensate for the small gap.
"I really like the half of the CAS equation"
It should be half the groundspeed (not CAS) and multiply by 10 to get a 3deg ROD. (same as 5* GS). It's easy to do quickly and great for descent, non-prec app etc.
I don't think CDA's are possible to SS 05 at all times and I don't think the approach you did was expected to be a CDA either. I was told it was due to airspace restrictions to the south. We need a SS director guru to correct me on this.
Could the same or similarly informed Guru tell us who is are the worst at sticking to speeds especially 170 to 5 or 160 to 4? It is amazing how close some a/c get even when you have been sticking well to the speeds. Now and then we keep 160 to 2 (or 170 to 3) to compensate for the small gap.
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I can do the simple maths, not all this half GS stuff, but both are useful as a quick check.
As regards the STN airspace I am aware of that on 05 and often use speedbrakes to get down to where they want us, it was just the last little bit I was referring to.
Never thought of how big a difference the speeds make, maybe will have to go for Flap 2 to keep the exact speed (not that I ever didn't...)
As regards the STN airspace I am aware of that on 05 and often use speedbrakes to get down to where they want us, it was just the last little bit I was referring to.
Never thought of how big a difference the speeds make, maybe will have to go for Flap 2 to keep the exact speed (not that I ever didn't...)
I say there boy
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SS director needs traffic downwind for RW 05 to get down to alt 3,000ft quickly as the TMA controllers own 4,000ft to the south-west of the field for London City traffic. That's at least one of the reasons why there are no CDAs for 05 at SS.
