When to Activate Approach Phase

As the title suggests. When flying the stock A320, when is the exact point you should activate the approach phase on the MCDU? 20 miles out, 50 miles, out, when entering the STAR?

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It will enable automatically at the DECEL waypoint. But sometimes that is way too close to the destination and I will enable it when I want to start slowing earlier or when getting to a speed restriction.

Then I can continue to slow further with each extension of the flaps.

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As a general rule I follow, is when I see the lateral needle in the display start to move left or right. I then enable app mode, but caveat, this is in Boeing aircraft, never fly Airbus planes. I also did it this way when flying the TBM-930, and it worked excellent then too. However, another gotcha, I have not had more than 5 successful ILS approaches in MSFS, as the planes are very poor in correct performance with the FMS/AP system. I am providing my input based on FSX and X-Plane ILS approaches instructions and the way I was taught by a MD-11 Captain for Delta Air Lines. The plane system sees the ILS a long time before you get to GS final turn, but why tax it, just wait till the needle moves and then engage APP mode. The plane will align onto the GS and then follow it down. Most pilots take control between 4 miles out and 400 feet, which is about what I do. I have thousands successful flights all over USA and Middle/far east airports in FSX in C-17. I have thousands of successful landings in FSX in the 747/737 all over USA from Mississippi River west, i.e., SFO, PDX, PHX, LAX, SEA, Spokane, WA, Boise, ID, too many to mention. I did crash the C-17 on Midway, IS when B-52 was sitting on the taxiway, loading out bombs and ordnance, and I was not sure it was real, turned out it was.

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Approach phase is NOT the same as approach mode.

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You’re correct. It will switch on it’s own at DECEL during my last flight. Didn’t know that. I find I’m too rushed getting the plane configured if I leave it that late.

From an actual operations practice, approach MODE is usually activated when ATC clears the IFR flight for the approach. That’s when the controller would expect the aircraft to be slowing to final approach speed and configuration for landing.

Prior to this, ATC - would be providing vectors, speed, and or you’d be following the STAR so you’d most likely never get close to the magenta “D” - decelerate point where the aircraft would begin slowing, as the configuration allows, to vAPP.

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As an aside, in US, normally ATC does not give speed calls. Your approach plan would already have those in it I believe. In Europe, as I understand it, ATC will give you speed calls, although I have never flown in Europe. I am still trying to get this working in US. The (and correct me if I am wrong), IFR-HI/Low airways and your SIDS/Stars dictate speeds, and rule is not over 250 KIAS below 10,000. I usually (without any foreknowledge) slow down to 220 or below when under 10K feet, and 5-8 miles out I slow to 180, at about 500 feet before touchdown, mostly chop throttle to idle as angle and inertia will carry me to threshold of RW. Over end of RW, engage full spoilers, if speed is still above where it should be. This is in reference to 787/747/C-17 which is mostly all I fly except F-14, and its approach and landing is another whole profile, as that plane if configured correctly can land as slow as 137KIAS.

Not sure if you’re referring to MSFS or real-world flying but in the US ATC absolutely will assign speeds. It is a tool they have to manage traffic flow in the terminal areas and other areas as needed to ensure adequate separation.

Listen to any major US international airport approach frequency on Liveatc.net and you’ll here speed calls issued quite frequently. In the US we have a general speed restriction of 250k below 10,000’ as you mentioned. There are also a speed restriction around B, C, and D airspaces for certain conditions which limit speeds to 200 kts. You can look that up for more detail.

Whatever works for your speed management in the simulator as it’s all a game unless you’re trying to fly your aircraft “by the book” and following your own simulated ATC based on real world procedures in your head.

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Same in EU, some larger airports have a speed profile to follow, unless otherwise cleared by ATC:

  • 250 kts until IAF, then slow to 220 kts.
  • Reduce to 180 kts on base / intercept heading.
  • When established on localizer reduce to 160 kts.
  • Maintain 160 kts until 4 nm, then final approach speed.

Usually 220 kts until 8 nm, 180 kts at 6 nm, then 160 kts to 4 nm works fine.

So to answer the question of the OP, activate approach phase when starting declaration, whatever method or procedure you follow.

If there are no such restriction as above, this is another way to calculate when to start deceleration:

Deceleration segment:

  • 1 nm per 10 kts in level-flight without speed brakes.
  • 2 nm per 10 kts during descent without speed brakes.

When planning on using speed brakes, divide the above by 2.

Assuming you are flying 250 kts below 10.000 ft and you really don’t want to be flying any faster than 180 kts at the FAF/FAP → 250 - 180 = 70, which means you should start deceleration no later than 7 nm prior FAF/FAP when planning to decelerate in level flight or double that (14 nm) when performing a continuous descent.

Usually turboprops have no problem decelerating during descent, speed x 10 gives you the height above ground to start deceleration, you will reach final approach speed at 500 ft. On instrument approaches you need to be stable at 1000 ft so add 500 ft. So 250 kts x 10 + 500 ft = 3000 ft above ground. Works for most turboprops.

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All - I did not know ATC in states-controlled speed. My only experience is in sim, should have realized it was bogus. I have once had ATC assign me speed no faster than 220. However then never descend me soon enough to catch the ILS correctly. If I use X-Plane ATC is got some errors in it too. I am sure FSX did as well. I am getting to old to try Vatsim and the like. But listening might be fun, so thank you for the link. MS71

Problem in MSFS is that ATC talks you through all the altitude and speed restrictions on arrival which is wrong, in real life you are simply cleared for the arrival which includes any altitude / speed restrictions.

I doubt it very much. You absolutely should KNOW what they are, but you will be TOLD what speed to do.
This example for instance, from EGLL: heathrow approach radio

Not necessarily, at busy airports at busy times when there is lots of traffic, of course you get vectored and speed / altitude restrictions (example EGLL) to effectively manage the flow of traffic. But when flying an arrival procedure, ATC won’t talk you through all the speed and altitude restrictions which are part of that procedure. You will simply be cleared to follow the arrival which includes adhering to any speed and altitude restrictions which may exist unless cleared otherwise. Thats the point I’m trying to make. If you fly an arrival in MSFS ATC clears you down step by step in accordance with the altitude restrictions for that arrival procedure, same for speed restrictions. Thats not how it works in real life.

Yep. And here’s an example if you don’t. :slight_smile:

Exactly that!

Not doing 180 until established and 160 until 4 also tend to make them go cranky…

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Another reference video. I stumbled across this channel and there are a few short videos I found interesting.

Oh nooo, ditch that guy, he is a complete fraud…

Interesting! Can you elaborate?

Watch this video, he is a complete clown… Doesn’t even understand how wind works. Hope nobody actually takes this nonsense into the cockpit.

  • An aircraft weather vaning in the air when disconnecting the autopilot, really?
  • Differential thrust into the wind during flight.
  • Crosswind becoming a quartering headwind in flight.
  • Boeing 737 not certified for sideloads, not true, allowed to land without de-crabbing up to 40 kts crosswind, although not recommended on a dry runway.
  • Differential reverse thrust during landing roll.

A320 and B737 are not allowed to land with any side loads on the gear (not true by the way), how are you planning to land with 50 kts crosswind with no sideloads? Good luck fully de crabbing with 50 kts of wind and use bank to fully counter drift without planting the wingtip and engine nacelle into the ground.