Descent degrees query

I seen previously before online that you can change your v/s metrics to degrees.

How do you change this?

Doubt it. Wouldn’t make sense. Three degrees tells you nothing you really need to know. It’s about airspeed and descent rate. To expand on that, if you keep a 3-degree descent and your airspeed is all over the place, not consistent, knowing that you are descending at a particular angle ain’t gonna help you much.

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By pressing the small button inbetween heading and v/s. Here’s a lot of information: https://www.quora.com/What-are-the-functions-of-FPA-flight-path-angle-knob-in-the-MCP-of-an-Airbus-A320-and-when-it-used

@StatesideSiren4 this is actually a pretty nifty feature from the airbus really showing its worth during non-precision approaches. You don’t have to keep fighting with airspeed and required vs that never really work out good, and instead just say you want a 3° flight angle to the runway

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Well… not really. First of all it’s illegal (granted, we’re flying simulators, and it doesn’t matter). Second, non-precision approaches by definition do not have a glide slope. The angle is for reference only, when it’s even given (and remember, it’s not always 3 degrees). Plus, in an Airbus you’re just twisting a knob to set the airspeed and descent rate, so it shouldn’t be an issue to begin with.

Thank you very much!

MAYBE it’s illegal worldwide today, no source and not taking anyone’s word. But a FPA mode approach has been the cause of an accident that led to the addition of the 00’s to VS mode

The BEA found that Flight 148 crashed because the pilots left the autopilot set in Vertical Speed Mode instead of Flight Path Angle Mode and then set “33” for “3.3° descent angle”, resulting in a high descent rate of 3,300 feet (1,000 m) per minute into terrain.
(https://en.m.wikipedia.org/wiki/Air_Inter_Flight_148)

And even if it’s only for reference, it’s still easier to use fpa on a non-pris because that is given on 99% of the approach charts. Same ammount of focus is necessary as you would on VS/IAS mode

Disregard those that claim this is somehow illegal. The FPA mode is available on all B777s and when used properly is just as safe as SPD/V/S. The FCTM provides considerable information for the crew as to when FPA is or is not recommended. When FPA is selected, there appears a bracket on the PFD as an aid to monitoring the selected FPA. The FMS provides a FPV (flight path vector) for use as a reference or as a cross check. VNAV is the preferred mode and if not available FLCH is preferred for altitude changes except during approaches. FPA can be used instead of V/S mode for non precision approaches.

Wrong

What? You have fixed distances and fixed altitudes = fixed angle (or glidepath)
If you are using FPA or V/S is up to you.

Doesn’t this apply to all aircraft?

In an Airbus you do not need to use VS…NOTICE I SAID VS not FPA… You should control your descent with Speed. Pull the Alt Knob so you are in OPEN DESCENT and then adjust the speed.

High Speed = Higher Descent : Lower Speed = slower (lees fpm) descent. Taking away managed modes, VS is not generally used as the main manual way to descend.

Sadly until we have a study level Bus, bad habits are being learnt. But understandable as we have to work with what we have, but the OP Des works well in the sim.

Full Document here
https://safetyfirst.airbus.com/control-your-speed-during-descent-approach-and-landing/

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This is very helpful thanks!

I don’t agree. IRL you are usually descending at a fixed speed and hence you have to adjust V/S.
If you are not using the managed descent, V/S is usually standard, especially since open descent can result significant pitch and V/S changes.

Not sure what you mean, but descending in V/S is definitely not a bad habit!

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Real Airbus Pilots say so. I dont know. VS is not a constant speed… VS means the plane targets the FPM not speed which is more important. Hence VS is referred to at times as Very Stupid!

Do as you wish, I will post you a video of a real airbus pilot explaining it, It maybe a Bus thing?

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I never wrote that. I wrote constant speed = IAS

Never ever heard that in many decades of flying.

No, not an Airbus thing.

IF you are real pilot then you do what you do. It maybe a company SOP. But I can assure you, VS is not the go too over OP DESCENT.

If you are at FL370 and told descent to FL240, it will be managed or OP not VS. maybe for small changes I dont know,

That’s plain and simple wrong, especially at lower altitudes and close to the airport.

In this restricted scenario this is correct.

Are you an Airbus Pilot?

Until a few years ago, yes.

Well then you know better than me. I am passing on the info from a Current and real Airbus pilot., So perhaps once I find the video and post it you should you take that up with him.

Why on earth should I??? Different personal preferences, different SOPs etc.

Because he states it is not used and gives the reasons why? I assume there is very good reason for it
In any case the Airbus stuff posted backs up his reasons. I just need to find the video.