TOD and wind
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Make it so simple a caveman can do it. 3 X altitude +/- 10% for winds 10% of TAS or multiples of and add 7 for the slowdown at 10,000. Sometimes you are taken off an arrival routing and cleared direct so if you expect it will happen like going into MEX or BOG most of the time you are ready and don't look like an amateur speedbraking all the way down.
33,000 X 3= 99 + 10 for 50 K tailwind + 7 to slow for 116 miles. Easy and on descent as the speed diminishes you can update progress to fudge the speed a bit to always be in the slot with no power or speedbrakes. Our airline considered it poor planning if you used speedbrakes or power before 1,000 ft unless you were given vectors or speed restrictions on the descent. It made it fun. At normal descent speeds of course you had to add a few miles if you were heavy and take a few off if you were light.
VNAV works most of the time but takes you out of the loop especially if you didn't notice that holding pattern on the arrival that you won't really be doing.
33,000 X 3= 99 + 10 for 50 K tailwind + 7 to slow for 116 miles. Easy and on descent as the speed diminishes you can update progress to fudge the speed a bit to always be in the slot with no power or speedbrakes. Our airline considered it poor planning if you used speedbrakes or power before 1,000 ft unless you were given vectors or speed restrictions on the descent. It made it fun. At normal descent speeds of course you had to add a few miles if you were heavy and take a few off if you were light.
VNAV works most of the time but takes you out of the loop especially if you didn't notice that holding pattern on the arrival that you won't really be doing.
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Whats been said about speed brakes in this thread... what a load of BS.
The speed brakes are a normal part of the aircrafts flight controls - use them as appropriate.
Perfect example is when ATC tells you to keep the rate and slow down. You can be an ass and say that you are unable (hopefully they will sequence you behind the other more reasonable and professional pilots). Or you can help to make the traffic flow work by complying as best as possible within the limitations of the aircraft (witch includes the use of speed brakes).
Another good example of airmanship use of speed brakes is if you don't know how long your distance to go would be (for the Microsoft pilots that appear to have been commenting here, that would be in the case of where ATC is giving you radar vectors). For the sake of economy it would be advisable to keep a descend path somewhat between what you think would be the shortest distance and the longest that ATC would vector you). Thereby keeping the path just high enough that you can take the shorter distance with the speed brakes and the longer distance with a minimum use of thrust (=fuel).
Posters commenting in this thread, who are retired dinosaurs used to fly in an airspace as the only aircraft, are excused...
The speed brakes are a normal part of the aircrafts flight controls - use them as appropriate.
Perfect example is when ATC tells you to keep the rate and slow down. You can be an ass and say that you are unable (hopefully they will sequence you behind the other more reasonable and professional pilots). Or you can help to make the traffic flow work by complying as best as possible within the limitations of the aircraft (witch includes the use of speed brakes).
Another good example of airmanship use of speed brakes is if you don't know how long your distance to go would be (for the Microsoft pilots that appear to have been commenting here, that would be in the case of where ATC is giving you radar vectors). For the sake of economy it would be advisable to keep a descend path somewhat between what you think would be the shortest distance and the longest that ATC would vector you). Thereby keeping the path just high enough that you can take the shorter distance with the speed brakes and the longer distance with a minimum use of thrust (=fuel).
Posters commenting in this thread, who are retired dinosaurs used to fly in an airspace as the only aircraft, are excused...
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I guess you would consider me as one of your dino over the hill guys because I retired at 60 a few years ago but my currently flying friend is having a cocktail as we speak across the table from me and says everything is the same today as a few years ago so I disregard your last post as BS. A good pilot will use energy management to efficiently fly his aircraft as he is paid to do. It takes a little planning but that is what he is paid for. If you want to make every descent with speedbrakes, knock yourself out but you are wasting fuel and your fellow pilot will wonder why you don't plan better no matter which seat he is in. It is uncomfortable because the passengers feel the buffeting and guys like me know you weren't on your game for that descent. We usually know when the speedbrakes were an operational necessity or to fix a screw up. Have a nice day. Think I will top off my wine glass.
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VNAV takes into account many variables you dont want to think about calculating...current weight, temperatures, GPA, and speed control.
Speed brakes are over used, most of the time due to lack of experience, and not in anyones best interest....de-stabilize flight, give the passengers a rough ride, and waste fuel, not to mention the FOQUA bust.
Speed brakes are over used, most of the time due to lack of experience, and not in anyones best interest....de-stabilize flight, give the passengers a rough ride, and waste fuel, not to mention the FOQUA bust.
Whats been said about speed brakes in this thread... what a load of BS.
The speed brakes are a normal part of the aircrafts flight controls - use them as appropriate.
The speed brakes are a normal part of the aircrafts flight controls - use them as appropriate.
fair enough, I suppose you are not paying for it
I suppose Microsoft pilots never have to worry about wasting fuel and making someone else pay for it.
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John Citizen
So its ok to waste fuel then ?
fair enough, I suppose you are not paying for it
I suppose Microsoft pilots never have to worry about wasting fuel and making someone else pay for it.
So its ok to waste fuel then ?
fair enough, I suppose you are not paying for it
I suppose Microsoft pilots never have to worry about wasting fuel and making someone else pay for it.
To be able to avoid using the speed brakes you have to calculate your descend according to the shortest possible route. But when ATC then gives you another 20-30 nm vectoring you are down low and will use more fuel.
I say, it's more efficient to stay a little higher and if indeed you get the shortcut, pull the brakes. Of course you shouldn't plan for the longest imaginable route either, as the speed brakes will then not make it up if you get the shortest of the short cuts. So it's a compromise, and knowing you destination and how the traffic usually flows.
Now looking over a number of flights, there are 3 outcomes:
1) Sometimes you get the longer way and don't have to use the speed brakes, hence you saved some fuel by not having to fly level at a lower altitude.
2) Sometimes you were bang on.
3) Sometimes you got a shorter route and pulled the speed brakes.
Statistically, it's more likely that you didn't get the shortcut every time and hence in the other circumstances you saved fuel. And hence (Bubbers44), I will not use the speed brakes in every descend. However sometimes I will use the speed brakes as part of a planned, deliberate and calculated action.
If you always plan for the shortest route and doesn't get the shortcut you are wasting fuel.
Clear now?
Of course, if the situation allows I also prefer to increase speed before pulling the speed brakes. However, in the scenario outlined above with high traffic density it's rarely an option. I don't know about the traffic levels in Florida or where ever you flew, but in the major European airports there is a reason if ATC tells you to keep 1500 or more and reduce to 250 or less. You don't want to bump into the guy crossing your path 20 miles in front of you and you don't want to catch up on the guy ahead of you. ATC didn't screw up, these are the circumstances - deal with it!
If I fly to low traffic density airports I will of course plan for the shortest route, and if kept high due to crossing traffic use speed to negate that.
What irritated me enough to write the previous post was Bagot's and Hawker's extremely simplified and ignorant comments about the use of speed brakes.
I believe I argued my point why it's ok to use the speed brakes, and will agree to that much that they are not there to make up for lack of planning. However, they can be part of the plan too.
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I edit my original post
Speed Brake = "pilot error correction lever"
OR
"ATC f#%k you around lever" (ATC unexpectantly slow you down /reduce your track miles to run)
Speed Brake = "pilot error correction lever"
OR
"ATC f#%k you around lever" (ATC unexpectantly slow you down /reduce your track miles to run)
Like a few on here I spent most of my working life in civil aviation and, it should go without saying, am familiar with the principles of descent energy management (or should that be 'decent'?).
Yes, of course, under appropriate circumstances, one can, e.g. having failed to obtain further descent clearance, reduce ROD and speed and then, when cleared, accellerate with a transient increase in ROD.
What if you have been allocated a speed by ATC or are approaching min speed? Well, then you have to apply power and put unwanted energy into the system which will, at some stage, require removal.
Suppose you have the choice of speedbrake or extended routing to lose altitude; remember this: during the increased time of extended routing your engines are still using idle thrust fuel.
I now fly only as a passenger and it worries me that my PiC may think that speed brake = loss of face. I'd rather it was used when NECESSARY - you'll know when that is. Don't let misplaced pride get you into a rushed approach.
Finally, when landing easterly at LHR could you all please arrange to be at idle thrust and on or a little above the path when turning base from the north?
Bas, Marlow.
Yes, of course, under appropriate circumstances, one can, e.g. having failed to obtain further descent clearance, reduce ROD and speed and then, when cleared, accellerate with a transient increase in ROD.
What if you have been allocated a speed by ATC or are approaching min speed? Well, then you have to apply power and put unwanted energy into the system which will, at some stage, require removal.
Suppose you have the choice of speedbrake or extended routing to lose altitude; remember this: during the increased time of extended routing your engines are still using idle thrust fuel.
I now fly only as a passenger and it worries me that my PiC may think that speed brake = loss of face. I'd rather it was used when NECESSARY - you'll know when that is. Don't let misplaced pride get you into a rushed approach.
Finally, when landing easterly at LHR could you all please arrange to be at idle thrust and on or a little above the path when turning base from the north?
Bas, Marlow.
