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B7378 tips?

Old 3rd Aug 2020, 17:27
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B7378 tips?

Hi,

Iím going to be transitioning onto this type. Wondering if anybody has any valuable tips and tricks please especially with the FMS. Iíve read a few popular books on the type.

Something I donít understand is why do you enter a FL restriction in the FMS and end it often with a Ďbí even though it might be Ďatí?

Thanks

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Old 3rd Aug 2020, 18:30
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You might want to clarify whether by "B7378" you mean the 737-8 (i.e. Max 8, assuming you're an optimist) or 737-800.
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Old 3rd Aug 2020, 18:35
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The "B" actually means "at or below". And the aircraft will never descend below the altitude set in the altitude window on the MCP. It will enter ALT HOLD or VNAV ALT (as installed) if the selected altitude is above the restriction in the LEGS page.
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Old 3rd Aug 2020, 18:50
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FL210B means you want the aircraft to be at or below that altitude. You're basically telling VNAV you want s continuous descent as long as you're using VNAV. VNAV will calculate the profile for you to follow down and tell you if you're high or low on it.

Same goes for speed like usually we put 180B for speed inside the 10NM range of the airport and VNAV will calculate your slow down points and show you in the navigation display your decel points.

If you programme VNAV correctly it works really well for descent management and planning and doesn't require any mental math to be on profile like your 3 times altitude.

Usually I set 220 knots below for a downwind leg and 180 knots below for base and follow the VNAV profile down.

A magenta.bug will appear much like an ILS glideslope sort of to tell you how high or low you are on profile in descent.

Even if you're not using VNAV for descent you can still follow the pathing information if gives you, you don't need to be in VNAV for the path to be accurate.

It's always a good reference to use as long as you programmed the FMC correctly. You need to keep updating it if you're not in VNAV and updating your speed in the FMC if you're not following the speed you selected because if you have a path of 260 knots set and you're actually doing 300 knots in descent it's not accurate for you and can catch you out.

Always update your speed in the FMC if you're not following it for extended periods.
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Old 3rd Aug 2020, 18:56
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Thanks for the replies. If I was cleared lower would I have to delete the FL21B in the fms or would it do it itself, presuming I put lower in the Mcp.

Say if there was an Ďatí FL but on a arrival which included a descent would I leave it as a FL or still enter a B after it ?

Any tips would be good too. Yes the 800. I thought the max was the 8200!

Thanks
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Old 3rd Aug 2020, 19:09
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You could bug a lower altitude and press the ALT INTV on the MCP to delete the restriction, or just continue in LVL CH.

Wait to get your FCOM.
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Old 3rd Aug 2020, 22:33
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and doesn't require any mental math to be on profile like your 3 times altitude.
Even if you're not using VNAV for descent you can still follow the pathing information if gives you, you don't need to be in VNAV for the path to be accurate.
I would be careful how you interpret that advice. Always cross check your vertical profile with basic maths. The VNAV profile can be incorrect through finger trouble 20 minutes ago,or through a computer fault.
Also, when it is not appropriate to be using vnav ( 4 miles from an 8 nm final on a base leg, on vectors and the controller cuts you in) then you will be used to doing the calcs and wonít be tempted to go digging in the CDU.
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Old 3rd Aug 2020, 23:12
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I agree, always crosscheck with DTGx3. Often you can encounter a tailwind in the descent that is not accounted for in your OFP's descent winds. Personally I like to visualise things and I put a 10nm ring and 30nm ring around the intended landing runway. Depending on the direction I come from, I either select the RW or the FAF/FAP with crossing altitude in the descent page to get Vertical Bearing information. It's a great tool but not many use it.
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Old 4th Aug 2020, 09:05
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Originally Posted by Negan View Post
FL210B means you want the aircraft to be at or below that altitude. You're basically telling VNAV you want s continuous descent as long as you're using VNAV. VNAV will calculate the profile for you to follow down and tell you if you're high or low on it.

Same goes for speed like usually we put 180B for speed inside the 10NM range of the airport and VNAV will calculate your slow down points and show you in the navigation display your decel points.

If you programme VNAV correctly it works really well for descent management and planning and doesn't require any mental math to be on profile like your 3 times altitude.

Usually I set 220 knots below for a downwind leg and 180 knots below for base and follow the VNAV profile down.

A magenta.bug will appear much like an ILS glideslope sort of to tell you how high or low you are on profile in descent.

Even if you're not using VNAV for descent you can still follow the pathing information if gives you, you don't need to be in VNAV for the path to be accurate.

It's always a good reference to use as long as you programmed the FMC correctly. You need to keep updating it if you're not in VNAV and updating your speed in the FMC if you're not following the speed you selected because if you have a path of 260 knots set and you're actually doing 300 knots in descent it's not accurate for you and can catch you out.

Always update your speed in the FMC if you're not following it for extended periods.
rubbish.
Refrain from reprogramming the fmc unless you get a new runway, star or waypoints below 10.000ft. or in congested airspace. Even as PM. Keep things simple. Type type type is poor airmanship In the Terminal area, and when I see this on linechecks, you will get a comment on it.
if you get a different speed, deal with it, do your mental maths, the vertical profile indicator will still give you your position compared to the original programmed path, and will continue to do so. Otherwise, learn to interpret the 3x rule, learn how to interpret the speed/altitude/distance for your type and get to know how your aircraft behaves using your instruments and maps, instead of overrelying on a computer.

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Old 4th Aug 2020, 09:51
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Asking the PM to reprogram the speed in the descent page is the equivalent of getting a direct to a waypoint and sequence said waypoint on top of the legs page in the terminal area. Unless you'd rather proceed in HDG SEL to the cleared waypoint.
​​​​​​

Last edited by Banana Joe; 4th Aug 2020 at 10:05.
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Old 4th Aug 2020, 10:32
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Originally Posted by Icelanta View Post
rubbish.
Refrain from reprogramming the fmc unless you get a new runway, star or waypoints below 10.000ft. or in congested airspace. Even as PM. Keep things simple. Type type type is poor airmanship In the Terminal area, and when I see this on linechecks, you will get a comment on it.
if you get a different speed, deal with it, do your mental maths, the vertical profile indicator will still give you your position compared to the original programmed path, and will continue to do so. Otherwise, learn to interpret the 3x rule, learn how to interpret the speed/altitude/distance for your type and get to know how your aircraft behaves using your instruments and maps, instead of overrelying on a computer.
One could say keeping FMC up-to-date with the situation (route, speed, vertical profile), which allows for high level of automation (LNAV/VNAV) where appropriate, would contribute to a higher situational awareness.

It takes as many actions to change FMC speed on the 737 as it does to switch engine anti-ice on/off - four. Three digits for the speed and execute. Is that too much for a competent pilot to type in?
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Old 4th Aug 2020, 11:59
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Originally Posted by Paulm1949 View Post
Yes the 800. I thought the max was the 8200!
The Max is officially the 737-8 (or -7/-9/-10).

"8200" is Ryanair's marketing designation for their variant of the 737-8 with the extra door and accommodation for 200 or so passengers, in order to avoid the use of the term "Max".
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Old 4th Aug 2020, 12:40
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Originally Posted by FlyingStone View Post
One could say keeping FMC up-to-date with the situation (route, speed, vertical profile), which allows for high level of automation (LNAV/VNAV) where appropriate, would contribute to a higher situational awareness.

It takes as many actions to change FMC speed on the 737 as it does to switch engine anti-ice on/off - four. Three digits for the speed and execute. Is that too much for a competent pilot to type in?
is it too much for a competent pilot not to have to constantly change the fmc for any change that atc is giving you, and keep both heads up? Stop the bloody typing below fl100.
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Old 4th Aug 2020, 14:48
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Originally Posted by Paulm1949 View Post
Hi,

Iím going to be transitioning onto this type. Wondering if anybody has any valuable tips and tricks please especially with the FMS. Iíve read a few popular books on the type.

(...)
Out of curiosity - can you please provide list of these books? I'd love to check them out

&
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Old 4th Aug 2020, 15:05
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I’m going to be transitioning onto this type. Wondering if anybody has any valuable tips and tricks please especially with the FMS.


Presumably you will do the type rating in the simulator. That being so, ask the instructor to teach you how to hand fly on raw data using manual throttles. That means lots of touch and go circuits. Forget using the flight director at this stage. In other words learn to fly the aircraft first before getting overwhelmed with computer programming which you can learn during line training.

Much depends on the attitude of your simulator instructors. Most tend to start off with full use of the automatics and precious little basic hand flying. That is usually because they lack the ability to fly manually themselves. If you are having touble with landings in the simulator then ask the instructor to demonstrate how to land. A picture is worth a thousand words. Unfortunately few simulator instructors will chance their arm at a physical demonstration in case they stuff it up.

Unless you learn to fly the machine first you will quickly lose confidence in your ability to fly the aeroplane without all the automatics goodies. The worst addiction you will have is blind reliance on the flight director. It is vital you have equal competency at both hand flying raw data and monitoring the automatics. You should aim to have the skill to seamlessly switch from automatics to hand flying without having a panicky moment. Unless you can do that your confidence will be shot and automatics will become your crutch.
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Old 4th Aug 2020, 15:37
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Originally Posted by Icelanta View Post
is it too much for a competent pilot not to have to constantly change the fmc for any change that atc is giving you, and keep both heads up? Stop the bloody typing below fl100.
There's more than one way to fly
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Old 4th Aug 2020, 15:46
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With Icelanta on this.
Its all well and good being a whiz with the FMC, what happens that fateful day you lose it.
Below FL100, the last thing you want is the airplane happily flying downhill at 250 kts and your head is in the box.
The is a lot more to flying than constantly playing with the bloody computer.
Situational Awareness, is knowing where you are in space and time, not following a bloody magenta line without question.
Paulm1949, you will find the green banana will help a lot more than finger tapping the FMC, the VNAV can catch you out if you over rely on it.
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Old 4th Aug 2020, 15:52
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I see this in the sim, time and time again, over relianace on FMC especially in the terminal area. Sadly it seems to be the norm for one of the major 738 operators in Europe to teach this method.
An aviator does not need a computer to know how to fly
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Old 5th Aug 2020, 05:25
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Originally Posted by 73qanda View Post
Also, when it is not appropriate to be using vnav ( 4 miles from an 8 nm final on a base leg, on vectors and the controller cuts you in)
I still would! (in a 75 that is)
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Old 5th Aug 2020, 09:40
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I still would! (in a 75 that is)
75 73 ....it makes no difference.
I can’t think of one scenario where one pilot going heads down, and then requiring the second pilot to also go heads down to execute, is better/ safer/ lower workload than using the MCP to fly to final from a base leg. I’m sure there are some but they escape me. As a general rule, fly the plane simply using the most appropriate level of automation to the runway. So what’s the most appropriate level on a base leg with a change to tracking? The MCP in my book.
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