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B737 Speedbrake use question

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B737 Speedbrake use question

Old 30th Sep 2019, 16:46
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tae9141
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B737 Speedbrake use question

When you use speedbrake, do you make or is it recommended to make general call out such as 'speedbrake flight detent' ?
The company I fly for, making too many 'check' callouts and 'yes sirs' inside cockpit which really is ridiculous. Even emphasize things that are not mentioned in POM. When I watch videos on youtube and I do not see procedures too much complicated on foreign carriers. Dont know why.

Also, can we only use speedbrake when throttle is ARM or you are descending with level change?
Last time on my simulator session, FMC message popped up stating 'Drag Required' and noticed throttle was all the way down at IDLE.

Your comments and ideas will be greatly appreciated,

 
Old 30th Sep 2019, 17:33
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Why would you use the speedbrake with thrust levers in a position other than idle in a descent? Besides stopping the aircraft from exceeding Mmo/Vmo of course.
During a VNAV PTH//SPD or LVL CHG descend, it is normal to have the autothrottle channel FMA announce ARM (after RETARD). You use the speedbrake to increase deceleration rate in a level segment, increase rate of an idle descent or help the aircraft decelerate faster at a fixed V/S (generally not more than 800 fpm below 250 kts).

As for callouts, it depends on the company. You may like it or not, but as long as those are in the OMB or whatever it is called over there in the US, you should stick to them. If you have a case against it, raise it to whoever is of concern. Where I work we don't have such callouts, we don't have "speed check and flaps X set" for the PM either.
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Old 30th Sep 2019, 22:49
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de minimus non curat lex
 
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Speedbrake (SB)

What is important in multi-crew operations is keeping the other pilot in the loop.
Therefore it is necessary to announce what you are about to do. That might well have been prompted by “DRAG REQUIRED” alert message. Your SOPs will specify the wording.

Why would you want to deploy the SB when the TLs were not in idle?
You use SB during the descent ( LVL CHG) to increase the ROD.
You might use it in level flight to increase the rate of speed reduction.

When additional calls are called for by a company over and above “Boeing standard”, it probably due to a previous event and management is now trying to mitigate future threats.

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Old 1st Oct 2019, 01:49
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When additional calls are called for by a company over and above “Boeing standard”, it probably due to a previous event and management is now trying to mitigate future threats.
Unfortunately there are some "managements" that seem to think the more 'advisory' comments made by each pilot, the better is the CRM. So in the end it becomes a competition of subtle point scoring. This can be irritating.

"Mitigating future threats" is another motherhood statement that gets right up the nose of some pilots. Boeing use the term 'Verify' and that implies you don't have to articulate - you simply use your eyes.

I remember observing a Japanese check captain sitting at the back of a 737 simulator quietly observing a series of assessment circuits on candidates that had applied for a job in his airline. None of the pilots being tested knew each other and most came from different countries and different airlines with different procedures. It didn't help that the English language skill of the Japanese assessor was poor.

During one circuit the chap in the left seat as PF wasn't flying very well and his PM in the right seat thought he needed coaching. The PM was an Eastern European who could not resist "advising" the bewildered South American PF from the beginning of the downwind leg of the circuit until the end of the landing roll. Most of the time the PM was talking so fast in accented English that the poor bugger in the left seat hadn't a clue what he was saying yet wasn't game to tell him to shut up in front of the Japanese assessor.

As the simulator operator I had to button my lip although I was sorely tempted to say for goodness sake back-off and let the PF fly the aeroplane. Bit it wasn't my train set and it was up to the Japanese checkie to run the show. After the landing we went for a coffee break. On the side I commented to the check captain that I thought that PM was a bit too voluble and in fact may have distracted the PF who was having enough trouble flying the simulator. To my astonishment, the Japanese assessor whose English was very limited, and clearly didn't have a clue what the PM was gabbling about, smiled broadly and said he thought the PM was showing excellent CRM by the amount of advice he was offering to the PF.

The PM was hired by the Japanese operator and I pitied the pilots he would be flying with. The inevitable happened and three months later the PM was sacked after numerous complaints from the Japanese captains he flew with that they were distracted by his non-stop "advice" on how to fly the 737.

There are times when silence is golden. Unfortunately it seems to be a rare commodity on today's flight decks..
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Old 1st Oct 2019, 03:44
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Originally Posted by Parkfell
What is important in multi-crew operations is keeping the other pilot in the loop.
Therefore it is necessary to announce what you are about to do.
No. If you're the PF, you do it and then announce from the FMA (if that's your SOP). Speedbrakes do not need to be called; that's what the other pilot has eyeballs for, if he/she hasn't already noted that some energy destruction is now required.

If you're the PNF/PM, you don't do anything unless told to by the PF eg flaps, gear (or unless covered by SOPs such as switchery after reaching some trigger/flow action point).

Originally Posted by Centaurus
There are times when silence is golden.
Silent dark cockpits = good.
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Old 1st Oct 2019, 16:30
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Not sure about the rights or wrongs of announcing "Speed Brake", but please keep your hand on the lever all the time when using them.
Also, why isn't there an interlock between power levers and speed brake levers so that if power is applied the speed brakes are stowed?
(I am thinking of the 1995 Cali B757 accident.)
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Old 2nd Oct 2019, 03:36
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Originally Posted by dixi188 View Post
Also, why isn't there an interlock between power levers and speed brake levers so that if power is applied the speed brakes are stowed?
Because at high altitude when you hit a wind shear or mountain wave and the speed starts moving rapidly toward Mmo, you need to use the speed brakes to slow instead of ripping the throttles toward idle. I've seen it done the other way, and it isn't pretty.
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Old 2nd Oct 2019, 07:49
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Originally Posted by Capn Bloggs View Post
No. If you're the PF, you do it and then announce from the FMA (if that's your SOP). Speedbrakes do not need to be called; that's what the other pilot has eyeballs for, if he/she hasn't already noted that some energy destruction is now required.
This is be governed by your company SOP. Whilst I appreciate your logic for experienced crews, and that may well be your company’s SOP; there are many ways to skin the cat.

So the SB answer can be (a) YES (b) NO (c) another opinion

Announce from the FMA??


Junior Birdmen might find it helpful to keep a “sticky mit” on top of the SB whilst deployed.
More seasoned campaigners perhaps do not. Just as long as they remember to close it as thrust is applied levelling off.
Whatever works for you.....
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Old 2nd Oct 2019, 08:24
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Originally Posted by Parkfell
Announce from the FMA??
Sorry, I was not implying any speedbrake call from the FMA. That was directed at things that the PM might not see/realise has happened eg button pushes into different autoflight modes. A speedbrake call on the other hand is ridiculous.

Originally Posted by Parkfell
Junior Birdmen might find it helpful to keep a “sticky mit” on top of the SB whilst deployed.
Been in the game for 30+ years and I still do this. Too easy to forget they're out, especially when one is slow. Always remember a incident writeup in Flight International years ago where a 757 landed heavily with the boards out. Boeing said "it's annunciated on the XXX panel, why would we need to have any other warning?". "Hands On speedbrake lever until stowed" was then mentioned.
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Old 2nd Oct 2019, 08:33
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And AIRMANSHIP passing 1000’RA might have reminded the chaps to close the SB, and confirm ALT WINDOW set to G/A platform.

May, or may not be a SOP............but it does no harm.

Many ways to skin the cat.
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Old 2nd Oct 2019, 13:37
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I always announce "Speed brake flight detent" anytime I use it. For me it is just a crm matter and also to involve the PM in the action. Here is the reason: usually we use the speedbrake to catch up a descent path for being too high (i.e we have an extra total energy) or instructed by atc to expedite descent. In both cases our workload can increase rapidly especially during arrival/approach (starting to configure the aircraft, complying with speed or altitude restriction, ...) so when we remove our hand from the speedbrake lever to the mcp to set a new speed or altitude then setting the altimeter when passing the transition level we may forget to bring our hand back to the speedbrake lever. And since the PM is "actively" involved he/she will be more aware about the speedbrake position.

As for using speedbrake and opening thrust at the same time I can't see the reason unless during an emergency descent + need of using engine anti-ice at the same time. In normal operation, it is like braking and accelerating at the same time. You will waste fuel, energy and put an unnecessary load on the aircraft structure.
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Old 2nd Oct 2019, 17:34
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Originally Posted by Tomaski View Post
Because at high altitude when you hit a wind shear or mountain wave and the speed starts moving rapidly toward Mmo, you need to use the speed brakes to slow instead of ripping the throttles toward idle. I've seen it done the other way, and it isn't pretty.
Unless you enjoy unplanned descents...
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Old 2nd Oct 2019, 22:22
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Originally Posted by Tomaski View Post
Because at high altitude when you hit a wind shear or mountain wave and the speed starts moving rapidly toward Mmo, you need to use the speed brakes to slow instead of ripping the throttles toward idle. I've seen it done the other way, and it isn't pretty.
There could always be an auto-stowed at certain TLA or N1. If the jet was overspeeding, the TLA would be likely below or moving to a lower power setting with the A/T on.
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Old 3rd Oct 2019, 06:28
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Originally Posted by dixi188 View Post
Not sure about the rights or wrongs of announcing "Speed Brake", but please keep your hand on the lever all the time when using them.
Also, why isn't there an interlock between power levers and speed brake levers so that if power is applied the speed brakes are stowed?
(I am thinking of the 1995 Cali B757 accident.)

That is what happens on the 757 / 67 but only on the ground with weight on wheels, takes care of retracting spoilers with a late go around after touchdown
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Old 3rd Oct 2019, 09:17
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Originally Posted by stilton View Post



That is what happens on the 757 / 67 but only on the ground with weight on wheels, takes care of retracting spoilers with a late go around after touchdown
Also on the A300 and I think all modern airliners for the Go Around situation.

Dixi
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Old 3rd Oct 2019, 09:54
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And also the B737.
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Old 3rd Oct 2019, 10:22
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If I have deployed the speed brakes, I keep my hand on the lever, and use my ‘outboard’ hand to adjust the FCU if required, or ask the other pilot to change settings for me

Airbus FBW annunciates when the speed brakes are deployed, and auto-stows the speed brakes any time TOGA is selected, (actually if thrust levers are above MCT).
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Old 4th Oct 2019, 08:40
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Having flown Airbus for many years, I do scan the memo, and as you know, the FBW and cockpit layout is a very well thought out system, and also reminds you if you apply power with speed brakes still out.

I have flown other types though, including Boeing 737 classic, which does not have very good annunciations, so keeping a hand on the lever is a good insurance policy against distractions.

I deploy the speed brake with my inboard hand, which is the same hand I use for adjusting the FCU. It’s not the end of the world if I have to take my hand off the speed brake lever, but I don’t unless I have to.
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Old 4th Oct 2019, 12:56
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Originally Posted by Uplinker View Post
Having flown Airbus for many years, I do scan the memo, and as you know, the FBW and cockpit layout is a very well thought out system, and also reminds you if you apply power with speed brakes still out.

I have flown other types though, including Boeing 737 classic, which does not have very good annunciations, so keeping a hand on the lever is a good insurance policy against distractions.

I deploy the speed brake with my inboard hand, which is the same hand I use for adjusting the FCU. It’s not the end of the world if I have to take my hand off the speed brake lever, but I don’t unless I have to.
My apologies about misunderstanding inboard and outboard. Obviously it's the inboard hand that does everything from speed brake to FCU. The advice to include Memo was in general not specifically you. Surely you must be doing it already.
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Old 4th Oct 2019, 13:54
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.
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