Usage of speed brakes, v/s, etc.
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""I avoid using speedbrake to the maximum. The buffet is uncomfortable and they usually reveal poor descent planning.
On the 320 the managed descent usually leaves me below profile
I like to use VS mode, It is more comfortable, if im confronted with having to reduce speed i activate the approach phase getting rid of the speed bug or simply select a lower speed so i dont have to worry about the thrust increasing,
I control the speed with a combination of VS and speedbrake if required.
If above profile i press EXP DES down to 5000 if required ATC permiting. The extra drag from high speed descent really helps to capture the profile. "
Like the pilot said when ATC asked the pilots to expedite descent the pilot said these speed brakes are for my mistakes, not yours. I hate using speed brakes too, it means I wasn't minding the store or ATC kept me high and fast.
On the 320 the managed descent usually leaves me below profile
I like to use VS mode, It is more comfortable, if im confronted with having to reduce speed i activate the approach phase getting rid of the speed bug or simply select a lower speed so i dont have to worry about the thrust increasing,
I control the speed with a combination of VS and speedbrake if required.
If above profile i press EXP DES down to 5000 if required ATC permiting. The extra drag from high speed descent really helps to capture the profile. "
Like the pilot said when ATC asked the pilots to expedite descent the pilot said these speed brakes are for my mistakes, not yours. I hate using speed brakes too, it means I wasn't minding the store or ATC kept me high and fast.
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this is a very amusing topic to read the replies.
at school they taught me to plan always such a way that you preserve enough energy to go all the way from TOD to Final, without using any thrust other then (full)idle.
now with the company i work for we usually do this, and as taught, speedbrakes is a way of correcting for bad planning of descend and getting back on profile, or when ATC requires a quicker descend.
using the speedbrakes mean you're literally throwing away energy, and that's bad airmanship.
you should get to know you aircraft and plan accordingly when to start your descend so to not use it.
and where you're flying a star which requires some step downs, you can also apply this theory.
as long as you're not throwing out the energy.
i fly the md80, here we have vnav but usually i use the v/s and plan it myself. this because the vnav requires input data of the current winds for it to predict your TOD.
using the V/S you can anticipate going above profile, increase your RoD (while still above 10,000ft) and go under profile, keep going under profile which the increased speed, then start earlier to reduce your RoD when you're approaching 10,000 so as to reduce your speed to 250kts.
and then depending on your weight, you maintain the required RoD(v/s) so to maintain the 250kts all the way down to your given altitude.
with a good planning taking into account head and tail winds / freezing level and actual weights/mass, you'll do this time after time without going out of idle thrust, and certainly not using speedbrakes.
practice makes prefect.
at school they taught me to plan always such a way that you preserve enough energy to go all the way from TOD to Final, without using any thrust other then (full)idle.
now with the company i work for we usually do this, and as taught, speedbrakes is a way of correcting for bad planning of descend and getting back on profile, or when ATC requires a quicker descend.
using the speedbrakes mean you're literally throwing away energy, and that's bad airmanship.
you should get to know you aircraft and plan accordingly when to start your descend so to not use it.
and where you're flying a star which requires some step downs, you can also apply this theory.
as long as you're not throwing out the energy.
i fly the md80, here we have vnav but usually i use the v/s and plan it myself. this because the vnav requires input data of the current winds for it to predict your TOD.
using the V/S you can anticipate going above profile, increase your RoD (while still above 10,000ft) and go under profile, keep going under profile which the increased speed, then start earlier to reduce your RoD when you're approaching 10,000 so as to reduce your speed to 250kts.
and then depending on your weight, you maintain the required RoD(v/s) so to maintain the 250kts all the way down to your given altitude.
with a good planning taking into account head and tail winds / freezing level and actual weights/mass, you'll do this time after time without going out of idle thrust, and certainly not using speedbrakes.
practice makes prefect.
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using the speedbrakes mean you're literally throwing away energy, and that's bad airmanship.
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We played a game at our airline where you had to plan your weight and wind in a 737 so when you went to idle power at FL350 you couldn't touch power until 1,000 ft to stabilize or use speed brakes or you lost, all you could do was vary the speed a bit to stay on profile. It wasn't that hard and saved fuel plus made you a better pilot by keeping you in tune with how to efficiently use your piloting skills to get the most out of your aircraft. I even did it with the 757 because knowing how we would be maneuvering for landing I could do it better than the VNAV.
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That is what I claim. I can do better than the FMGC... Frequently.
I don't mind using speedbrakes if my calculations were not accurate or circumstances change, which happens frequently too. But I try not to use them until it is clear that I have too much energy and it is not advisable to convert that excess energy in reduced flight time.
I don't mind using speedbrakes if my calculations were not accurate or circumstances change, which happens frequently too. But I try not to use them until it is clear that I have too much energy and it is not advisable to convert that excess energy in reduced flight time.
Originally Posted by KingChango
using the speedbrakes mean you're literally throwing away energy, and that's bad airmanship.
Anybody who won't use the speedbrakes (or configure early...it's the same thing) to correct a high-energy state because of some misguided feeling of incompetence or saving fuel is a mug. Obviously you don't plan to get into a position where you need to use them, but once there, not to use them is plain silly.
I'de send myself to an early grave if I always tried to do better than the 717's VNAV.
Last edited by Capn Bloggs; 15th Jun 2012 at 06:59.
Bottums Up
and they usually reveal poor descent planning.
It's not my poor descent planning but without speed brake, it's extra track miles.
Intruder
Absolutely agree, but for many the "stick of shame" mentality is still deeply ingrained....
Bad airmanship is not being able to put the airplane where you want it, because you refuse to use provided controls.
